/**
 * Combined redistributable ease.js file
 *
 * For the original, uncombined and unminifed source, please visit
 * http://easejs.org.
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/**
 * ease.js namespace
 *
 * All modules will be available via this namespace. In CommonJS format, they
 * were accessed via the require() function. For example:
 *
 *   var util = require( 'easejs' ).Class;
 *
 * In this file, the above would be written as:
 *
 *   var util = easejs.Class;
 *
 * @type  {Object}
 */
var easejs = {};

( function( ns_exports )
{
    /**
     * CommonJS module exports
     *
     * Since this file contains all of the modules, this will be populated with
     * every module right off the bat.
     *
     * @type  {Object.<string,Object>}
     */
    var module = {};

    /**
     * Returns the requested module
     *
     * The require() function is likely unavailable client-side (within a web
     * browser). Therefore, we mock one. If it is available, this overwrites it.
     * Our modules are all preloaded in the exports object.
     *
     * @param  {string}  module_id  id of the module to load
     *
     * return tag intentionally omitted; too many potential return types and
     * setting return type of {*} will throw warnings for those attempting to
     * treat the return value as a function
     */
    var require = function( module_id )
    {
        // remove the './' directory prefix (every module is currently included
        // via a relative path), stupidly remove ../'s and remove .js extensions
        var id_clean = module_id.replace( /^\.?\/|[^/]*?\/\.\.\/|\.js$/, '' );

        // attempt to retrieve the module
        var mod = module[ id_clean ];
        if ( mod === undefined )
        {
            throw "[ease.js] Undefined module: " + module_id;
        }

        return mod.exports;
    };

/** prop_parser **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * Property keyword parser module
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 */

/**
 * Known (permitted) keywords
 * @type {Object.<string,boolean>}
 */
var _keywords = {
    'public':    true,
    'protected': true,
    'private':   true,
    'static':    true,
    'abstract':  true,
    'const':     true,
    'virtual':   true,
    'override':  true,
    'proxy':     true
};


/**
 * Parses property keywords
 *
 * @param  {string}  prop  property string, which may contain keywords
 *
 * @return  {{name: string, keywords: Object.<string, boolean>}}
 */
exports.parseKeywords = function ( prop )
{
    var name        = prop,
        keywords    = [],
        keyword_obj = {};

    prop = ''+( prop );

    // only perform parsing if the string contains a space
    if ( / /.test( prop ) )
    {
        // the keywords are all words, except for the last, which is the
        // property name
        keywords = prop.split( /\s+/ );
        name     = keywords.pop();

        var i       = keywords.length,
            keyword = '';

        while ( i-- )
        {
            keyword = keywords[ i ];

            // ensure the keyword is recognized
            if ( !_keywords[ keyword ] )
            {
                throw Error(
                    "Unexpected keyword for '" + name + "': " + keyword
                );
            }

            keyword_obj[ keyword ] = true;
        }
    }

    return {
        name:     name,
        keywords: keyword_obj
    };
}
} )( module['prop_parser'] = {}, '.' );
/** util **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * Contains utilities functions shared by modules
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 */

var propParseKeywords = require( __dirname + '/prop_parser' ).parseKeywords;


/**
 * Whether we can actually define properties, or we need to fall back
 *
 * This check actually attempts to set a property and fails if there's an error.
 * This is needed because IE8 has a broken implementation, yet still defines
 * Object.defineProperty for use with DOM elements. Just another day in the life
 * of a web developer.
 *
 * This test is only performed once, when the module is first loaded. Don't
 * expect a performance hit from it.
 *
 * @type  {boolean}
 */
var can_define_prop = ( function()
{
    if ( typeof Object.defineProperty === 'function' )
    {
        try
        {
            // perform test, primarily for IE8
            Object.defineProperty( {}, 'x', {} );
            return true;
        }
        catch ( e ) {}
    }

    return false;
} )();


/**
 * Freezes an object if freezing is supported
 *
 * @param  {Object}  obj  object to freeze
 *
 * @return  {Object}  object passed to function
 */
exports.freeze = ( typeof Object.freeze === 'function' )
    ? Object.freeze
    : function( obj )
    {
        return;
    }
;


/**
 * Gets/sets whether the system needs to fall back to defining properties in a
 * normal manner when use of Object.defineProperty() is requested
 *
 * This will be set by default if the JS engine does not support the
 * Object.defineProperty method from ECMAScript 5.
 *
 * @param  {boolean=}  val  value, if used as setter
 *
 * @return  {boolean|Object}  current value if getter, self if setter
 */
exports.definePropertyFallback = function( val )
{
    if ( val === undefined )
    {
        return !can_define_prop;
    }

    can_define_prop = !val;
    exports.defineSecureProp = getDefineSecureProp();

    return exports;
};


/**
 * Attempts to define a non-enumerable, non-writable and non-configurable
 * property on the given object
 *
 * If the operation is unsupported, a normal property will be set.
 *
 * @param  {Object}  obj    object to set property on
 * @param  {string}  prop   name of property to set
 * @param  {*}       value  value to set
 *
 * @return  {undefined}
 */
exports.defineSecureProp = getDefineSecureProp();


/**
 * Clones an object
 *
 * @param  {*}         data  object to clone
 * @param  {boolean=}  deep  perform deep clone (defaults to shallow)
 *
 * @return  {*}  cloned object
 *
 * Closure Compiler ignores typeof checks and is thusly confused:
 * @suppress {checkTypes}
 */
exports.clone = function clone( data, deep )
{
    deep = !!deep;

    if ( data instanceof Array )
    {
        if ( !deep )
        {
            // return a copy of the array
            return data.slice( 0 );
        }

        // if we're performing a deep clone, we have to loop through each of the
        // elements of the array and clone them
        var ret = [];
        for ( var i = 0, len = data.length; i < len; i++ )
        {
            // clone this element
            ret.push( clone( data[ i ], deep ) );
        }

        return ret;
    }
    else if ( typeof data === 'function' )
    {
        // It is pointless to clone a function. Even if we did clone those that
        // support toSource(), they'd still do the same damn thing.
        return data;
    }
    // explicitly testing with instanceof will ensure we're actually testing an
    // object, not something that may be misinterpreted as one (e.g. null)
    else if ( data instanceof Object )
    {
        var newobj = {},
            hasOwn = Object.prototype.hasOwnProperty;

        // copy data to the new object
        for ( var prop in data )
        {
            if ( hasOwn.call( data, prop ) )
            {
                newobj[ prop ] = ( deep )
                    ? clone( data[ prop ] )
                    : data[ prop ]
                ;
            }
        }

        return newobj;
    }

    // primitive type; cloning unnecessary
    return data;
};


/**
 * Copies properties from one object to another
 *
 * This method is designed to support very basic object extensions. The
 * destination argument is first to allow extending an object without using the
 * full-blown class system.
 *
 * If a deep copy is not performed, all values will be copied by reference.
 *
 * @param  {Object}   dest  destination object
 * @param  {Object}   src   source object
 * @param  {boolean}  deep  perform deep copy (slower)
 *
 * @return  {Object}  dest
 */
exports.copyTo = function( dest, src, deep )
{
    deep = !!deep;

    var get, set, data;

    // sanity check
    if ( !( dest instanceof Object ) || !( src instanceof Object ) )
    {
        throw TypeError(
            "Must provide both source and destination objects"
        );
    }

    // slower; supports getters/setters
    if ( can_define_prop )
    {
        for ( var prop in src )
        {
            data = Object.getOwnPropertyDescriptor( src, prop );

            if ( data.get || data.set )
            {
                // Define the property the slower way (only needed for
                // getters/setters). We don't have to worry about cloning in
                // this case, since getters/setters are methods.
                Object.defineProperty( dest, prop, data );
            }
            else
            {
                // normal copy; cloned if deep, otherwise by reference
                dest[ prop ] = ( deep )
                    ? exports.clone( src[ prop ], true )
                    : src[ prop ]
                ;
            }
        }
    }
    // quick (keep if statement out of the loop)
    else
    {
        for ( var prop in src )
        {
            // normal copy; cloned if deep, otherwise by reference
            dest[ prop ] = ( deep )
                ? exports.clone( src[ prop ], true )
                : src[ prop ]
            ;
        }
    }

    // return dest for convenience (and to feel useful about ourselves)
    return dest;
};


/**
 * Parses object properties to determine how they should be interpreted in an
 * Object Oriented manner
 *
 * @param  {!Object}  data     properties with names as the key
 *
 * @param  {!{each,property,method,getset,keywordParser}}  options
 *         parser options and callbacks
 *
 * @return undefined
 */
exports.propParse = function( data, options )
{
    // todo: profile; function calls are more expensive than if statements, so
    // it's probably a better idea not to use fvoid
    var fvoid          = function() {},
        callbackEach   = options.each          || undefined,
        callbackProp   = options.property      || fvoid,
        callbackMethod = options.method        || fvoid,
        callbackGetSet = options.getset        || fvoid,
        keywordParser  = options.keywordParser || propParseKeywords,

        hasOwn = Object.prototype.hasOwnProperty,

        parse_data = {},
        name       = '',
        keywords   = {},
        value      = null,
        getter     = false,
        setter     = false;

    // for each of the given properties, determine what type of property we're
    // dealing with (in the classic OO sense)
    for ( var prop in data )
    {
        // ignore properties of instance prototypes
        if ( !( hasOwn.call( data, prop ) ) )
        {
            continue;
        }

        // retrieve getters/setters, if supported
        if ( can_define_prop )
        {
            var prop_desc = Object.getOwnPropertyDescriptor( data, prop );
            getter = prop_desc.get;
            setter = prop_desc.set;
        }

        // do not attempt to retrieve the value if a getter is defined (as that
        // would then call the getter)
        value = ( typeof getter === 'function' )
            ? undefined
            : data[ prop ];

        parse_data = keywordParser( prop ) || {};
        name       = parse_data.name || prop;
        keywords   = parse_data.keywords || {};

        if ( options.assumeAbstract || keywords[ 'abstract' ] )
        {
            // may not be set if assumeAbstract is given
            keywords[ 'abstract' ] = true;

            if ( !( value instanceof Array ) )
            {
                throw TypeError(
                    "Missing parameter list for abstract method: " + name
                );
            }

            verifyAbstractNames( name, value );
            value = exports.createAbstractMethod.apply( this, value );
        }

        // if an 'each' callback was provided, pass the data before parsing it
        if ( callbackEach )
        {
            callbackEach.call( callbackEach, name, value, keywords );
        }

        // getter/setter
        if ( getter || setter )
        {
            callbackGetSet.call( callbackGetSet,
                name, getter, setter, keywords
            );
        }
        // method
        else if ( ( typeof value === 'function' ) || ( keywords[ 'proxy' ] ) )
        {
            callbackMethod.call(
                callbackMethod,
                name,
                value,
                exports.isAbstractMethod( value ),
                keywords
            );
        }
        // simple property
        else
        {
            callbackProp.call( callbackProp, name, value, keywords );
        }
    }
};


/**
 * Only permit valid names for parameter list
 *
 * In the future, we may add additional functionality, so it's important to
 * restrict this as much as possible for the time being.
 *
 * @param  {string}  name    name of abstract member (for error)
 * @param  {Object}  params  parameter list to check
 *
 * @return {undefined}
 */
function verifyAbstractNames( name, params )
{
    var i = params.length;
    while ( i-- )
    {
        if ( params[ i ].match( /^[a-z_][a-z0-9_]*$/i ) === null )
        {
            throw SyntaxError(
                "Member " + name + " contains invalid parameter '" +
                params[ i ] + "'"
            );
        }
    }
}


/**
 * Creates an abstract method
 *
 * Abstract methods must be implemented by a subclass and cannot be called
 * directly. If a class contains a single abstract method, the class itself is
 * considered to be abstract and cannot be instantiated. It may only be
 * extended.
 *
 * @param  {...string}  def  function definition that concrete
 *                           implementations must follow
 *
 * @return  {function()}
 */
exports.createAbstractMethod = function( def )
{
    var definition = Array.prototype.slice.call( arguments );

    var method = function()
    {
        throw new Error( "Cannot call abstract method" );
    };

    exports.defineSecureProp( method, 'abstractFlag', true );
    exports.defineSecureProp( method, 'definition', definition );
    exports.defineSecureProp( method, '__length', arguments.length );

    return method;
};


/**
 * Determines if the given function is an abstract method
 *
 * @param  {function()}  func  function to inspect
 *
 * @return  {boolean}  true if function is an abstract method, otherwise false
 *
 * @suppress {checkTypes}
 */
exports.isAbstractMethod = function( func )
{
    return ( ( typeof func === 'function') && ( func.abstractFlag === true ) )
        ? true
        : false
    ;
};


/**
 * Shrinks an array, removing undefined elements
 *
 * Pushes all items onto a new array, removing undefined elements. This ensures
 * that the length of the array represents correctly the number of elements in
 * the array.
 *
 * @param  {Array}  items  array to shrink
 *
 * @return  {Array}  shrunken array
 */
exports.arrayShrink = function( items )
{
    // copy the methods into a new array by pushing them onto it, to ensure
    // the length property of the array will work properly
    var arr_new = [];
    for ( var i = 0, len = items.length; i < len; i++ )
    {
        var item = items[ i ];
        if ( item === undefined )
        {
            continue;
        }

        arr_new.push( item );
    }

    return arr_new;
};


/**
 * Uses Object.getOwnPropertyDescriptor if available, otherwise provides our own
 * implementation to fall back on
 */
exports.getOwnPropertyDescriptor =
    ( can_define_prop && Object.getOwnPropertyDescriptor ) ||
    /**
     * If the environment does not support retrieving property descriptors
     * (ES5), then the following will be true:
     *  - get/set will always be undefined
     *  - writable, enumerable and configurable will always be true
     *  - value will be the value of the requested property on the given object
     *
     * @param  {!Object}  obj   object to check property on
     * @param  {string}   prop  property to retrieve descriptor for
     *
     * @return  {Object|undefined}  descriptor for requested property, if found
     */
    function( obj, prop )
    {
        if ( !Object.prototype.hasOwnProperty.call( obj, prop ) )
        {
            return undefined;
        }

        // fallback response
        return {
            get: undefined,
            set: undefined,

            writable:     true,
            enumerable:   true,
            configurable: true,

            value: obj[ prop ]
        };
    };


/**
 * Returns prototype of object, or undefined if unsupported
 */
exports.getPrototypeOf = Object.getPrototypeOf || function()
{
    return undefined;
};


/**
 * Travels down the prototype chain of the given object in search of the
 * requested property and returns its descriptor
 *
 * This operates as Object.getOwnPropertyDescriptor(), except that it traverses
 * the prototype chain. For environments that do not support __proto__, it will
 * not traverse the prototype chain and essentially serve as an alias for
 * getOwnPropertyDescriptor().
 *
 * This method has the option to ignore the base prototype. This is useful to,
 * for example, not catch properties like Object.prototype.toString() when
 * searching for 'toString' on an object.
 *
 * @param  {Object}   obj     object to check property on
 * @param  {string}   prop    property to retrieve descriptor for
 * @param  {boolean}  nobase  whether to ignore the base prototype
 *
 * @return  {Object}  descriptor for requested property or undefined if not found
 */
exports.getPropertyDescriptor = function( obj, prop, nobase )
{
    // false by default
    nobase = !!nobase;

    // note that this uses util's function, not Object's
    var desc = exports.getOwnPropertyDescriptor( obj, prop ),
        next = exports.getPrototypeOf( obj );

    // if we didn't find a descriptor and a prototype is available, recurse down
    // the prototype chain, ensuring that the next prototype has a prototype if
    // the base is to be excluded
    if ( !desc && next && ( !nobase || exports.getPrototypeOf( next ) ) )
    {
        return exports.getPropertyDescriptor( next, prop, nobase );
    }

    // return the descriptor or undefined if no prototype is available
    return desc;
};


/**
 * Indicates whether or not the getPropertyDescriptor method is capable of
 * traversing the prototype chain
 *
 * @type  {boolean}
 */
exports.defineSecureProp( exports.getPropertyDescriptor, 'canTraverse',
    ( Object.getPrototypeOf ) ? true : false
);


/**
 * Appropriately returns defineSecureProp implementation to avoid check on each
 * invocation
 *
 * @return  {function( Object, string, * )}
 */
function getDefineSecureProp()
{
    // falls back to simply defining a normal property
    var fallback = function( obj, prop, value )
    {
        obj[ prop ] = value;
    };

    if ( !can_define_prop )
    {
        return fallback;
    }
    else
    {
        // uses ECMAScript 5's Object.defineProperty() method
        return function( obj, prop, value )
        {
            try
            {
                Object.defineProperty( obj, prop,
                {
                    value: value,

                    enumerable:   false,
                    writable:     false,
                    configurable: false
                });
            }
            catch ( e )
            {
                // let's not have this happen again, as repeatedly throwing
                // exceptions will do nothing but slow down the system
                exports.definePropertyFallback( true );

                // if there's an error (ehem, IE8), fall back
                fallback( obj, prop, value );
            }
        };
    }
}

} )( module['util'] = {}, '.' );
/** warn **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * ease.js warning system
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 */

/**
 * Active warning handler
 * @type {?function( Warning )}
 */
var _handler = null;

/**
 * Console to use for logging
 *
 * This reference allows an alternative console to be used. Must contain warn()
 * or log() methods.
 *
 * @type {Object}
 */
var _console = ( typeof console !== 'undefined' ) ? console : undefined;


/**
 * Permits wrapping an exception as a warning
 *
 * Warnings are handled differently by the system, depending on the warning
 * level that has been set.
 *
 * @param {Error} e exception (error) to wrap
 *
 * @return {Warning} new warning instance
 *
 * @constructor
 */
var Warning = exports.Warning = function( e )
{
    // allow instantiation without use of 'new' keyword
    if ( !( this instanceof Warning ) )
    {
        return new Warning( e );
    }

    // ensure we're wrapping an exception
    if ( !( e instanceof Error ) )
    {
        throw TypeError( "Must provide exception to wrap" );
    }

    Error.prototype.constructor.call( this, e.message );

    // copy over the message for convenience
    this.message = e.message;
    this.name    = 'Warning';
    this._error  = e;

    this.stack = e.stack &&
        e.stack.replace( /^.*?\n+/,
            this.name + ': ' + this.message + "\n"
        );
};

// ensures the closest compatibility...just be careful not to modify Warning's
// prototype
Warning.prototype = Error();
Warning.prototype.constructor = Warning;
Warning.prototype.name = 'Warning';


/**
 * Return the error wrapped by the warning
 *
 * @return {Error} wrapped error
 */
Warning.prototype.getError = function()
{
    return this._error;
};


/**
 * Core warning handlers
 * @type {Object}
 */
exports.handlers = {
    /**
     * Logs message to console
     *
     * Will attempt to log using console.warn(), falling back to console.log()
     * if necessary and aborting entirely if neither is available.
     *
     * This is useful as a default option to bring problems to the developer's
     * attention without affecting the control flow of the software.
     *
     * @param {Warning} warning to log
     *
     * @return {undefined}
     */
    log: function( warning )
    {
        var dest;

        _console && ( dest = _console.warn || _console.log ) &&
            dest.call( _console, ( 'Warning: ' + warning.message ) );
    },


    /**
     * Throws the error associated with the warning
     *
     * This handler is useful for development and will ensure that problems are
     * brought to the attention of the developer.
     *
     * @param {Warning} warning to log
     *
     * @return {undefined}
     */
    throwError: function( warning )
    {
        throw warning.getError();
    },


    /**
     * Ignores warnings
     *
     * This is useful in a production environment where (a) warnings will affect
     * the reputation of the software or (b) warnings may provide too much
     * insight into the software. If using this option, you should always
     * develop in a separate environment so that the system may bring warnings
     * to your attention.
     *
     * @param {Warning} warning to log
     *
     * @return {undefined}
     */
    dismiss: function( warning )
    {
        // do nothing
    }
};


/**
 * Sets the active warning handler
 *
 * You may use any of the predefined warning handlers or pass your own function.
 *
 * @param {function( Warning )} handler warning handler
 *
 * @return {undefined}
 */
exports.setHandler = function( handler )
{
    _handler = handler;
};


/**
 * Handles a warning using the active warning handler
 *
 * @param {Warning} warning warning to handle
 *
 * @return {undefined}
 */
exports.handle = function( warning )
{
    _handler( warning );
}


/**
 * Sets active console
 *
 * @param {Object} console containing warn() or log() method
 *
 * @return {undefined}
 */
exports.setConsole = function( console )
{
    _console = console;
};


// set the default handler
_handler = exports.handlers.log;

} )( module['warn'] = {}, '.' );
/** ClassBuilder **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * Handles building of classes
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 *
 * TODO: This module is currently being tested /indirectly/ by the class tests.
 *       This is because of a refactoring. All of this logic used to be part of
 *       the class module. Test this module directly, but keep the existing
 *       class tests in tact for a higher-level test.
 */

var util    = require( __dirname + '/util' ),
    warn    = require( __dirname + '/warn' ),
    Warning = warn.Warning,

    /**
     * IE contains a nasty enumeration "bug" (poor implementation) that makes
     * toString unenumerable. This means that, if you do obj.toString = foo,
     * toString will NOT show up in `for` or hasOwnProperty(). This is a problem.
     *
     * This test will determine if this poor implementation exists.
     */
    enum_bug = (
        Object.prototype.propertyIsEnumerable.call(
            { toString: function() {} },
            'toString'
        ) === false
    )
    ? true
    : false,

    /**
     * Hash of reserved members
     *
     * These methods cannot be defined in the class. They are for internal use
     * only. We must check both properties and methods to ensure that neither is
     * defined.
     *
     * @type {Object.<string,boolean>}
     */
    reserved_members = {
        '__initProps': true,
        'constructor': true
    },

    /**
     * Hash of methods that must be public
     *
     * Notice that this is a list of /methods/, not members, because this check
     * is performed only for methods. This is for performance reasons. We do not
     * have a situation where we will want to check for properties as well.
     *
     * @type {Object.<string,boolean>}
     */
    public_methods = {
        '__construct': true,
        'toString':    true,
        '__toString':  true
    };


/**
 * Initializes class builder with given member builder
 *
 * The 'new' keyword is not required when instantiating this constructor.
 *
 * @param  {Object}  member_builder  member builder
 *
 * @param  {VisibilityObjectFactory}  visibility_factory  visibility object
 *                                                        generator
 *
 * @constructor
 */
module.exports = exports =
function ClassBuilder( member_builder, visibility_factory )
{
    // allow ommitting the 'new' keyword
    if ( !( this instanceof exports ) )
    {
        // module.exports for Closure Compiler
        return new module.exports( member_builder, visibility_factory );
    }

    /**
     * Used for building class members
     * @type {Object}
     */
    this._memberBuilder = member_builder;

    /**
     * Generates visibility object
     * @type {VisibilityObjectFactory}
     */
    this._visFactory = visibility_factory;


    /**
     * Class id counter, to be increment on each new definition
     * @type {number}
     */
    this._classId = 0;

    /**
     * Instance id counter, to be incremented on each new instance
     * @type {number}
     */
    this._instanceId = 0;

    /**
     * Set to TRUE when class is in the process of being extended to ensure that
     * a constructor can be instantiated (to use as the prototype) without
     * invoking the class construction logic
     *
     * @type {boolean}
     */
    this._extending = false;

    /**
     * A flag to let the system know that we are currently attempting to access
     * a static property from within a method. This means that the caller should
     * be given access to additional levels of visibility.
     *
     * @type {boolean}
     */
    this._spropInternal = false;
};


/**
 * Default class implementation
 *
 * @return undefined
 */
exports.ClassBase = function Class() {};


/**
 * Default static property method
 *
 * This simply returns undefined, signifying that the property was not found.
 *
 * @param  {string}  prop  requested property
 *
 * @return  {undefined}
 */
exports.ClassBase.$ = function( prop, val )
{
    if ( val !== undefined )
    {
        throw ReferenceError(
            "Cannot set value of undeclared static property '" + prop + "'"
        );
    }

    return undefined;
};


/**
 * Returns a hash of the reserved members
 *
 * The returned object is a copy of the original. It cannot be used to modify
 * the internal list of reserved members.
 *
 * @return  {Object.<string,boolean>}  reserved members
 */
exports.getReservedMembers = function()
{
    // return a copy of the reserved members
    return util.clone( reserved_members, true );
};


/**
 * Returns a hash of the forced-public methods
 *
 * The returned object is a copy of the original. It cannot be used to modify
 * the internal list of reserved members.
 *
 * @return  {Object.<string,boolean>}  forced-public methods
 */
exports.getForcedPublicMethods = function()
{
    return util.clone( public_methods, true );
};


/**
 * Returns reference to metadata for the requested class
 *
 * Since a reference is returned (rather than a copy), the returned object can
 * be modified to alter the metadata.
 *
 * @param  {Function|Object}  cls  class from which to retrieve metadata
 *
 * @return  {__class_meta}
 */
exports.getMeta = function( cls )
{
    return cls.___$$meta$$ || {};
}


/**
 * Determines if the class is an instance of the given type
 *
 * The given type can be a class, interface, trait or any other type of object.
 * It may be used in place of the 'instanceof' operator and contains additional
 * enhancements that the operator is unable to provide due to prototypal
 * restrictions.
 *
 * @param  {Object}  type      expected type
 * @param  {Object}  instance  instance to check
 *
 * @return  {boolean}  true if instance is an instance of type, otherwise false
 */
exports.isInstanceOf = function( type, instance )
{
    var meta, implemented, i;

    if ( !( type && instance ) )
    {
        return false;
    }

    try
    {
        // check prototype chain (will throw an error if type is not a
        // constructor (function)
        if ( instance instanceof type )
        {
            return true;
        }
    }
    catch ( e ) {}

    // if no metadata is available, then our remaining checks cannot be
    // performed
    if ( !instance.__cid || !( meta = exports.getMeta( instance ) ) )
    {
        return false;
    }

    implemented = meta.implemented;
    i           = implemented.length;

    // check implemented interfaces
    while ( i-- )
    {
        if ( implemented[ i ] === type )
        {
            return true;
        }
    }

    return false;
};


/**
 * Mimics class inheritance
 *
 * This method will mimic inheritance by setting up the prototype with the
 * provided base class (or, by default, Class) and copying the additional
 * properties atop of it.
 *
 * The class to inherit from (the first argument) is optional. If omitted, the
 * first argument will be considered to be the properties list.
 *
 * @param  {Function|Object}  _   parent or definition object
 * @param  {Object=}          __  definition object if parent was provided
 *
 * @return  {Function}  extended class
 */
exports.prototype.build = function extend( _, __ )
{
    // ensure we'll be permitted to instantiate abstract classes for the base
    this._extending = true;

    var args      = Array.prototype.slice.call( arguments ),
        props     = args.pop() || {},
        base      = args.pop() || exports.ClassBase,
        prototype = this._getBase( base ),
        cname     = '',

        prop_init      = this._memberBuilder.initMembers(),
        members        = this._memberBuilder.initMembers( prototype ),
        static_members = {
            methods: this._memberBuilder.initMembers(),
            props:   this._memberBuilder.initMembers()
        },

        abstract_methods =
            util.clone( exports.getMeta( base ).abstractMethods )
            || { __length: 0 }
    ;

    // prevent extending final classes
    if ( base.___$$final$$ === true )
    {
        throw Error(
            "Cannot extend final class " +
                ( base.___$$meta$$.name || '(anonymous)' )
        );
    }

    // grab the name, if one was provided
    if ( cname = props.__name )
    {
        // we no longer need it
        delete props.__name;
    }

    // IE has problems with toString()
    if ( enum_bug )
    {
        if ( props.toString !== Object.prototype.toString )
        {
            props.__toString = props.toString;
        }
    }

    // increment class identifier
    this._classId++;

    // build the various class components (xxx: this is temporary; needs
    // refactoring)
    try
    {
        this.buildMembers( props,
            this._classId,
            base,
            prop_init,
            abstract_methods,
            members,
            static_members,
            function( inst )
            {
                return new_class.___$$svis$$;
            }
        );
    }
    catch ( e )
    {
        // intercept warnings /only/
        if ( e instanceof Warning )
        {
            warn.handle( e );
        }
        else
        {
            throw e;
        }
    }

    // reference to the parent prototype (for more experienced users)
    prototype.___$$parent$$ = base.prototype;

    // set up the new class
    var new_class = this.createCtor( cname, abstract_methods, members );

    // closure to hold static initialization to be used later by subtypes
    initStaticVisibilityObj( new_class );
    var staticInit = function( ctor, inheriting )
    {
        attachStatic( ctor, static_members, base, inheriting );
    }
    staticInit( new_class, false );

    this._attachPropInit(
        prototype, prop_init, members, new_class, this._classId
    );

    new_class.prototype             = prototype;
    new_class.prototype.constructor = new_class;
    new_class.___$$props$$          = prop_init;
    new_class.___$$methods$$        = members;
    new_class.___$$sinit$$          = staticInit;

    attachFlags( new_class, props );

    validateAbstract( new_class, cname, abstract_methods );

    // We reduce the overall cost of this definition by defining it on the
    // prototype rather than during instantiation. While this does increase the
    // amount of time it takes to access the property through the prototype
    // chain, it takes much more time to define the property in this manner.
    // Therefore, we can save a substantial amount of time by defining it on the
    // prototype rather than on each new instance via __initProps().
    util.defineSecureProp( prototype, '__self', new_class.___$$svis$$ );

    // create internal metadata for the new class
    var meta = createMeta( new_class, base );
    meta.abstractMethods = abstract_methods;
    meta.name            = cname;

    attachAbstract( new_class, abstract_methods );
    attachId( new_class, this._classId );

    // we're done with the extension process
    this._extending = false;

    return new_class;
};


exports.prototype._getBase = function( base )
{
    var type = ( typeof base );

    switch ( type )
    {
        // constructor (we could also check to ensure that the return value of
        // the constructor is an object, but that is not our concern)
        case 'function':
            return new base();

        // we can use objects as the prototype directly
        case 'object':
            return base;
    }

    // scalars
    throw TypeError( 'Must extend from Class, constructor or object' );
};


exports.prototype.buildMembers = function buildMembers(
    props, class_id, base, prop_init, abstract_methods, members,
    static_members, staticInstLookup
)
{
    var hasOwn = Array.prototype.hasOwnProperty,
        defs   = {},

        smethods = static_members.methods,
        sprops   = static_members.props,

        _self = this
    ;

    util.propParse( props, {
        each: function( name, value, keywords )
        {
            // disallow use of our internal __initProps() method
            if ( reserved_members[ name ] === true )
            {
                throw Error( name + " is reserved" );
            }

            // if a member was defined multiple times in the same class
            // declaration, throw an error
            if ( hasOwn.call( defs, name ) )
            {
                throw Error(
                    "Cannot redefine method '" + name + "' in same declaration"
                );
            }

            // keep track of the definitions (only during class declaration)
            // to catch duplicates
            defs[ name ] = 1;
        },

        property: function( name, value, keywords )
        {
            var dest = ( keywordStatic( keywords ) ) ? sprops : prop_init;

            // build a new property, passing in the other members to compare
            // against for preventing nonsensical overrides
            _self._memberBuilder.buildProp(
                dest, null, name, value, keywords, base
            );
        },

        getset: function( name, get, set, keywords )
        {
            var dest       = ( keywordStatic( keywords ) ) ? smethods : members,
                is_static  = keywordStatic( keywords ),
                instLookup = ( ( is_static )
                    ? staticInstLookup
                    : exports.getMethodInstance
                );

            _self._memberBuilder.buildGetterSetter(
                dest, null, name, get, set, keywords, instLookup, class_id, base
            );
        },

        method: function( name, func, is_abstract, keywords )
        {
            var is_static  = keywordStatic( keywords ),
                dest       = ( is_static ) ? smethods : members,
                instLookup = ( is_static )
                    ? staticInstLookup
                    : exports.getMethodInstance
            ;

            // constructor check
            if ( public_methods[ name ] === true )
            {
                if ( keywords[ 'protected' ] || keywords[ 'private' ] )
                {
                    throw TypeError(
                        name + " must be public"
                    );
                }
            }

            _self._memberBuilder.buildMethod(
                dest, null, name, func, keywords, instLookup,
                class_id, base
            );

            if ( is_abstract )
            {
                abstract_methods[ name ] = true;
                abstract_methods.__length++;
            }
            else if ( ( hasOwn.call( abstract_methods, name ) )
                && ( is_abstract === false )
            )
            {
                // if this was a concrete method, then it should no longer
                // be marked as abstract
                delete abstract_methods[ name ];
                abstract_methods.__length--;
            }
        }
    } );
}


/**
 * Validates abstract class requirements
 *
 * @param  {function()}  ctor              class
 * @param  {string}      cname             class name
 * @param  {{__length}}  abstract_methods  object containing abstract methods
 *
 * @return  {undefined}
 */
function validateAbstract( ctor, cname, abstract_methods )
{
    if ( ctor.___$$abstract$$ )
    {
        if ( abstract_methods.__length === 0 )
        {
            throw TypeError(
                "Class " + ( cname || "(anonymous)" ) + " was declared as " +
                "abstract, but contains no abstract members"
            );
        }
    }
    else
    {
        if ( abstract_methods.__length > 0 )
        {
            throw TypeError(
                "Class " + ( cname || "(anonymous)" ) + " contains abstract " +
                "members and must therefore be declared abstract"
            );
        }
    }
}


/**
 * Creates the constructor for a new class
 *
 * This constructor will call the __constructor method for concrete classes
 * and throw an exception for abstract classes (to prevent instantiation).
 *
 * @param  {string}          cname             class name (may be empty)
 * @param  {Array.<string>}  abstract_methods  list of abstract methods
 * @param  {Object}          members           class members
 *
 * @return  {Function}  constructor
 */
exports.prototype.createCtor = function( cname, abstract_methods, members )
{
    // concrete class
    if ( abstract_methods.__length === 0 )
    {
        return this.createConcreteCtor( cname, members );
    }
    // abstract class
    else
    {
        return this.createAbstractCtor( cname );
    }
}


/**
 * Creates the constructor for a new concrete class
 *
 * This constructor will call the __constructor method of the class, if
 * available.
 *
 * @param  {string}  cname    class name (may be empty)
 * @param  {Object}  members  class members
 *
 * @return  {function()}  constructor
 */
exports.prototype.createConcreteCtor = function( cname, members )
{
    var args  = null,
        _self = this;

    /**
     * Constructor function to be returned
     *
     * The name is set to ClassInstance because some debuggers (e.g. v8) will
     * show the name of this function for constructor instances rather than
     * invoking the toString() method
     *
     * @constructor
     *
     * Suppressing due to complaints for using __initProps
     * @suppress {checkTypes}
     */
    function ClassInstance()
    {
        if ( !( this instanceof ClassInstance ) )
        {
            // store arguments to be passed to constructor and
            // instantiate new object
            args = arguments;
            return new ClassInstance();
        }

        initInstance( this );
        this.__initProps();

        // If we're extending, we don't actually want to invoke any class
        // construction logic. The above is sufficient to use this class in a
        // prototype, so stop here.
        if ( _self._extending )
        {
            return;
        }

        // generate and store unique instance id
        attachInstanceId( this, ++_self._instanceId );

        // call the constructor, if one was provided
        if ( typeof this.__construct === 'function' )
        {
            // note that since 'this' refers to the new class (even
            // subtypes), and since we're using apply with 'this', the
            // constructor will be applied to subtypes without a problem
            this.__construct.apply( this, ( args || arguments ) );
            args = null;
        }

        // attach any instance properties/methods (done after
        // constructor to ensure they are not overridden)
        attachInstanceOf( this );

        // Provide a more intuitive string representation of the class
        // instance. If a toString() method was already supplied for us,
        // use that one instead.
        if ( !( Object.prototype.hasOwnProperty.call(
            members[ 'public' ], 'toString'
        ) ) )
        {
            // use __toString if available (see enum_bug), otherwise use
            // our own defaults
            this.toString = members[ 'public' ].__toString
                || ( ( cname )
                    ? function()
                    {
                        return '#<' + cname + '>';
                    }
                    : function()
                    {
                        return '#<anonymous>';
                    }
                )
            ;
        }

    };

    // provide a more intuitive string representation
    ClassInstance.toString = ( cname )
        ? function() { return cname; }
        : function() { return '(Class)'; }
    ;

    return ClassInstance;
}


/**
 * Creates the constructor for a new abstract class
 *
 * Calling this constructor will cause an exception to be thrown, as abstract
 * classes cannot be instantiated.
 *
 * @param  {string}  cname  class name (may be empty)
 *
 * @return  {function()}  constructor
 */
exports.prototype.createAbstractCtor = function( cname )
{
    var _self = this;

    var __abstract_self = function()
    {
        if ( !_self._extending )
        {
            throw Error(
                "Abstract class " + ( cname || '(anonymous)' ) +
                    " cannot be instantiated"
            );
        }
    };

    __abstract_self.toString = ( cname )
        ? function()
        {
            return cname;
        }
        : function()
        {
            return '(AbstractClass)';
        }
    ;

    return __abstract_self;
}


/**
 * Attaches __initProps() method to the class prototype
 *
 * The __initProps() method will initialize class properties for that instance,
 * ensuring that their data is not shared with other instances (this is not a
 * problem with primitive data types).
 *
 * The method will also initialize any parent properties (recursive) to ensure
 * that subtypes do not have a referencing issue, and subtype properties take
 * precedence over those of the parent.
 *
 * @param  {Object}  prototype   prototype to attach method to
 * @param  {Object}  properties  properties to initialize
 *
 * @param  {{public: Object, protected: Object, private: Object}}  members
 *
 * @param  {function()}  ctor  class
 * @param  {number}     cid  class id
 *
 * @return  {undefined}
 */
exports.prototype._attachPropInit = function(
    prototype, properties, members, ctor, cid
)
{
    var _self = this;

    util.defineSecureProp( prototype, '__initProps', function( inherit )
    {
        // defaults to false
        inherit = !!inherit;

        var iid    = this.__iid,
            parent = prototype.___$$parent$$;

        // first initialize the parent's properties, so that ours will overwrite
        // them
        var parent_init = parent && parent.__initProps;
        if ( typeof parent_init === 'function' )
        {
            // call the parent prop_init, letting it know that it's been
            // inherited so that it does not initialize private members or
            // perform other unnecessary tasks
            parent_init.call( this, true );
        }

        // this will return our property proxy, if supported by our environment,
        // otherwise just a normal object with everything merged in
        var inst_props = _self._visFactory.createPropProxy(
            this, this.___$$vis$$, properties[ 'public' ]
        );

        // Copies all public and protected members into inst_props and stores
        // private in a separate object, which adds inst_props to its prototype
        // chain and is returned. This is stored in a property referenced by the
        // class id, so that the private members can be swapped on each method
        // request, depending on calling context.
        var vis = this.___$$vis$$[ cid ] = _self._visFactory.setup(
            inst_props, properties, members
        );

        // provide a means to access the actual instance (rather than the
        // property/visibility object) internally (this will translate to
        // this.__inst from within a method), but only if we're on our final
        // object (not a parent)
        if ( !inherit )
        {
            util.defineSecureProp( vis, '__inst', this );
        }
    });
}


/**
 * Determines if the given keywords should result in a static member
 *
 * A member will be considered static if the static or const keywords are given.
 *
 * @param {Object} keywords keywords to scan
 *
 * @return {boolean} true if to be static, otherwise false
 */
function keywordStatic( keywords )
{
    return ( keywords[ 'static' ] || keywords[ 'const' ] )
        ? true
        : false
    ;
}


/**
 * Creates and populates the static visibility object
 *
 * @param  {Function}  ctor  class
 *
 * @return  {undefined}
 */
function initStaticVisibilityObj( ctor )
{
    var _self = this;

    /**
     * the object will simply be another layer in the prototype chain to
     * prevent protected/private members from being mixed in with the public
     *
     * @constructor
     */
    var sobj = function() {};
    sobj.prototype = ctor;

    var sobji = new sobj();

    // override __self on the instance's visibility object, giving internal
    // methods access to the restricted static methods
    ctor.___$$svis$$ = sobji;

    // Override the class-level accessor method to allow the system to know we
    // are within a method. An internal flag is necessary, rather than using an
    // argument or binding, because those two options are exploitable. An
    // internal flag cannot be modified by conventional means.
    sobji.$ = function()
    {
        _self._spropInternal = true;
        var val = ctor.$.apply( ctor, arguments );
        _self._spropInternal = false;

        return val;
    };
}


/**
 * Attaches static members to a constructor (class)
 *
 * Static methods will be assigned to the constructor itself. Properties, on the
 * other hand, will be assigned to ctor.$. The reason for this is because JS
 * engines pre-ES5 support no means of sharing references to primitives. Static
 * properties of subtypes should share references to the static properties of
 * their parents.
 *
 * @param  {function()}  ctor        class
 * @param  {Object}      members     static members
 * @param  {function()}  base        base class inheriting from
 * @param  {boolean}     inheriting  true if inheriting static members,
 *                                   otherwise false (setting own static
 *                                   members)
 *
 * @return  {undefined}
 */
function attachStatic( ctor, members, base, inheriting )
{
    var methods = members.methods,
        props   = members.props,
        _self   = this
    ;

    // "Inherit" the parent's static methods by running the parent's static
    // initialization method. It is important that we do this before anything,
    // because this will recursively inherit all members in order, permitting
    // overrides.
    var baseinit = base.___$$sinit$$;
    if ( baseinit )
    {
        baseinit( ctor, true );
    }

    // initialize static property if not yet defined
    if ( !inheriting )
    {
        ctor.___$$sprops$$ = props;

        // provide a method to access static properties
        util.defineSecureProp( ctor, '$', function( prop, val )
        {
            // we use hasOwnProperty to ensure that undefined values will not
            // cause us to continue checking the parent, thereby potentially
            // failing to set perfectly legal values
            var has   = Object.prototype.hasOwnProperty,
                found = false,

                // Determine if we were invoked in the context of a class. If
                // so, use that.  Otherwise, use ourself.
                context = ( this.___$$sprops$$ ) ? this : ctor,

                // We are in a subtype if the context does not match the
                // constructor. This works because, when invoked for the first
                // time, this method is not bound to the constructor. In such a
                // case, we default the context to the constructor and pass that
                // down the line to each recursive call. Therefore, recursive
                // calls to subtypes will have a context mismatch.
                in_subtype = ( context !== ctor )
            ;

            // Attempt to locate the property. First, we check public. If not
            // available and we are internal (within a method), we can move on
            // to check other levels of visibility. `found` will contain the
            // visibility level the property was found in, or false.
            found = has.call( props[ 'public' ], prop ) && 'public';
            if ( !found && _self._spropInternal )
            {
                // Check for protected/private. We only check for private
                // properties if we are not currently checking the properties of
                // a subtype. This works because the context is passed to each
                // recursive call.
                found = has.call( props[ 'protected' ], prop ) && 'protected'
                    || !in_subtype
                        && has.call( props[ 'private' ], prop ) && 'private'
                ;
            }

            // if we don't own the property, let the parent(s) handle it
            if ( found === false )
            {
                // TODO: This check is simple, but quick. It may be worth
                // setting a flag on the class during definition to specify if
                // it's extending from a non-class base.
                return ( base.__cid && base.$ || exports.ClassBase.$ ).apply(
                    context, arguments
                );
            }

            var prop_item = props[ found ][ prop ];

            // if a value was provided, this method should be treated as a
            // setter rather than a getter (we *must* test using
            // arguments.length to ensure that setting to undefined works)
            if ( arguments.length > 1 )
            {
                // if const, disallow modification
                if ( prop_item[ 1 ][ 'const' ] )
                {
                    throw TypeError(
                        "Cannot modify constant property '" + prop + "'"
                    );
                }

                prop_item[ 0 ] = val;
                return context;
            }
            else
            {
                // return the value
                return prop_item[ 0 ];
            }
        } );
    }

    // copy over public static methods
    util.copyTo( ctor, methods[ 'public' ], true );
    util.copyTo( ctor.___$$svis$$, methods[ 'protected' ], true );

    // private methods should not be inherited by subtypes
    if ( !inheriting )
    {
        util.copyTo( ctor.___$$svis$$, methods[ 'private' ], true );
    }
}


/**
 * Initializes class metadata for the given class
 *
 * @param  {Function}  func     class to initialize metadata for
 * @param  {Function}  cparent  class parent
 *
 * @return  {undefined}
 *
 * Suppressed due to warnings for use of __cid
 * @suppress {checkTypes}
 */
function createMeta( func, cparent )
{
    var id          = func.__cid,
        parent_meta = ( ( cparent.__cid )
            ? exports.getMeta( cparent )
            : undefined
        );

    // copy the parent prototype's metadata if it exists (inherit metadata)
    if ( parent_meta )
    {
        func.___$$meta$$ = util.clone( parent_meta, true );
    }
    else
    {
        // create empty
        func.___$$meta$$ = {
            implemented: []
        };
    }

    // store the metadata in the prototype as well (inconsiderable overhead;
    // it's just a reference)
    func.prototype.___$$meta$$ = func.___$$meta$$;

    return func.___$$meta$$;
}


/**
 * Attaches an instance identifier to a class instance
 *
 * @param  {Object}  instance  class instance
 * @param  {number}  iid       instance id
 *
 * @return  {undefined}
 */
function attachInstanceId( instance, iid )
{
    util.defineSecureProp( instance, '__iid', iid );
}


/**
 * Initializes class instance
 *
 * This process will create the instance visibility object that will contain
 * private and protected members. The class instance is part of the prototype
 * chain.  This will be passed to all methods when invoked, permitting them to
 * access the private and protected members while keeping them encapsulated.
 *
 * For each instance, there is always a base. The base will contain a proxy to
 * the public members on the instance itself. The base will also contain all
 * protected members.
 *
 * Atop the base object is a private member object, with the base as its
 * prototype. There exists a private member object for the instance itself and
 * one for each supertype. This is stored by the class id (cid) as the key. This
 * permits the private member object associated with the class of the method
 * call to be bound to that method. For example, if a parent method is called,
 * that call must be invoked in the context of the parent, so the private
 * members of the parent must be made available.
 *
 * The resulting structure looks something like this:
 *   class_instance = { iid: { cid: {} } }
 *
 * @param  {Object}  instance  instance to initialize
 *
 * @return  {undefined}
 */
function initInstance( instance )
{
    /** @constructor */
    var prot = function() {};
    prot.prototype = instance;

    // add the visibility objects to the data object for this class instance
    instance.___$$vis$$ = new prot();
}


/**
 * Attaches partially applied isInstanceOf() method to class instance
 *
 * @param  {Object}  instance  class instance to attach method to
 *
 * @return  {undefined}
 */
function attachInstanceOf( instance )
{
    var method = function( type )
    {
        return module.exports.isInstanceOf( type, instance );
    };

    // TODO: To improve performance (defineSecureProp can be costly), simply
    // define a normal prop and freeze the class afterward. The class shouldn't
    // have any mutable methods.
    util.defineSecureProp( instance, 'isInstanceOf', method );
    util.defineSecureProp( instance, 'isA', method );
}


/**
 * Returns the instance object associated with the given method
 *
 * The instance object contains the protected members. This object can be passed
 * as the context when calling a method in order to give that method access to
 * those members.
 *
 * One level above the instance object on the prototype chain is the object
 * containing the private members. This is swappable, depending on the class id
 * associated with the provided method call. This allows methods that were not
 * overridden by the subtype to continue to use the private members of the
 * supertype.
 *
 * @param  {function()}  inst  instance that the method is being called from
 * @param  {number}      cid   class id
 *
 * @return  {Object|null}  instance object if found, otherwise null
 *
 * @suppress {checkTypes}
 */
exports.getMethodInstance = function( inst, cid )
{
    var iid  = inst.__iid,
        data = inst.___$$vis$$;

    return ( iid && data )
        ? data[ cid ]
        : null
    ;
}


/**
 * Attaches isAbstract() method to the class
 *
 * @param  {Function}  func     function (class) to attach method to
 * @param  {Array}     methods  abstract method names
 *
 * @return  {undefined}
 */
function attachAbstract( func, methods )
{
    var is_abstract = ( methods.__length > 0 ) ? true: false;

    /**
     * Returns whether the class contains abstract methods (and is therefore
     * abstract)
     *
     * @return  {boolean}  true if class is abstract, otherwise false
     */
    util.defineSecureProp( func, 'isAbstract', function()
    {
        return is_abstract;
    });
}


/**
 * Attaches the unique id to the class and its prototype
 *
 * The unique identifier is used internally to match a class and its instances
 * with the class metadata. Exposing the id breaks encapsulation to a degree,
 * but is a lesser evil when compared to exposing all metadata.
 *
 * @param  {function()}  ctor  constructor (class) to attach method to
 * @param  {number}      id    id to assign
 *
 * @return  {undefined}
 */
function attachId( ctor, id )
{
    util.defineSecureProp( ctor, '__cid', id );
    util.defineSecureProp( ctor.prototype, '__cid', id );
}


/**
 * Sets class flags
 *
 * @param  {Function}  ctor   class to flag
 * @param  {Object}   props  class properties
 *
 * @return  {undefined}
 */
function attachFlags( ctor, props )
{
    ctor.___$$final$$    = !!( props.___$$final$$ );
    ctor.___$$abstract$$ = !!( props.___$$abstract$$ );

    // The properties are no longer needed. Set to undefined rather than delete
    // (v8 performance)
    props.___$$final$$ = props.___$$abstract$$ = undefined;
}

} )( module['ClassBuilder'] = {}, '.' );
/** MethodWrapperFactory **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * Builds method wrappers
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 */


/**
 * Initializes factory to wrap methods
 *
 * @param  {function(Function,Function,number)}  factory  function that will
 *                                                        perform the actual
 *                                                        wrapping
 *
 * @constructor
 */
module.exports = exports = function MethodWrapperFactory( factory )
{
    // permit omission of the 'new' keyword for instantiation
    if ( !( this instanceof exports ) )
    {
        // module.exports for Closure Compiler
        return new module.exports( factory );
    }

    this._factory = factory;
};


/**
 * Wraps the provided method
 *
 * The returned function is determined by the factory function provided when the
 * MethodWrapperFactory was instantiated.
 *
 * @param  {function()}  method        method to wrap
 * @param  {function()}  super_method  super method, if overriding
 * @param  {number}      cid           class id that method is associated with
 * @param  {function()}  getInst       function to determine instance and return
 *                                     associated visibility object
 * @param  {string=}     name          name of method
 * @param  {Object=}     keywords      method keywords
 */
exports.prototype.wrapMethod = function(
    method, super_method, cid, getInst, name, keywords
)
{
    return this._factory( method, super_method, cid, getInst, name, keywords );
};

} )( module['MethodWrapperFactory'] = {}, '.' );
/** MethodWrappers **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * Default method wrapper functions
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 */

/**
 * Method wrappers for standard (non-fallback)
 * @type {Object}
 */
exports.standard = {
    wrapOverride: function( method, super_method, cid, getInst )
    {
        return function()
        {
            var context = getInst( this, cid ) || this,
                retval  = undefined
            ;

            // the _super property will contain the parent method (we don't
            // store the previous value for performance reasons and because,
            // during conventional use, it's completely unnecessary)
            context.__super = super_method;

            retval = method.apply( context, arguments );

            // prevent sneaky bastards from breaking encapsulation by stealing
            // method references (we set to undefined rather than deleting it
            // because deletion causes performance degradation within V8)
            context.__super = undefined;

            // if the value returned from the method was the context that we
            // passed in, return the actual instance (to ensure we do not break
            // encapsulation)
            if ( retval === context )
            {
                return this;
            }

            return retval;
        };
    },


    wrapNew: function( method, super_method, cid, getInst )
    {
        return function()
        {
            var context = getInst( this, cid ) || this,
                retval  = undefined
            ;

            // invoke the method
            retval = method.apply( context, arguments );

            // if the value returned from the method was the context that we
            // passed in, return the actual instance (to ensure we do not break
            // encapsulation)
            if ( retval === context )
            {
                return this;
            }

            return retval;
        };
    },


    wrapProxy: function( proxy_to, _, cid, getInst, name, keywords )
    {
        // it is important that we store only a boolean value as to whether or
        // not this method is static *outside* of the returned closure, so as
        // not to keep an unnecessary reference to the keywords object
        var is_static = keywords && keywords[ 'static' ];

        return function()
        {
            var context = getInst( this, cid ) || this,
                retval  = undefined,
                dest    = ( ( is_static )
                    ? context.$( proxy_to )
                    : context[ proxy_to ]
                )
            ;

            // rather than allowing a cryptic error to be thrown, attempt to
            // detect when the proxy call will fail and provide a useful error
            // message
            if ( !( ( dest !== null ) && ( typeof dest === 'object' )
                && ( typeof dest[ name ] === 'function' )
            ) )
            {
                throw TypeError(
                    "Unable to proxy " + name + "() call to '" + proxy_to +
                    "'; '" + proxy_to + "' is undefined or '" + name +
                    "' is not a function."
                );
            }

            retval = dest[ name ].apply( dest, arguments );

            // if the object we are proxying to returns itself, then instead
            // return a reference to *ourself* (so as not to break encapsulation
            // and to provide a more consistent and sensible API)
            return ( retval === dest )
                ? this
                : retval;
        };
    }
};

} )( module['MethodWrappers'] = {}, '.' );
/** MemberBuilder **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * Handles building members (properties, methods)
 *
 * This prototype could have easily been refactored into a number of others
 * (e.g. one for each type of member), but that refactoring has been deferred
 * until necessary to ensure ease.js maintains a relatively small footprint.
 * Ultimately, however, such a decision is a micro-optimization and shouldn't
 * harm the design and maintainability of the software.
 *
 * TODO: Implementation is inconsistent between various members. For example,
 * methods use ___$$keywords$$, whereas properties use [ val, keywords ]. Decide
 * on a common format.
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 */

var util       = require( __dirname + '/util' ),
    Warning    = require( __dirname + '/warn' ).Warning,
    visibility = [ 'public', 'protected', 'private' ]
;


/**
 * Responsible for building class members
 *
 * @param  {Function}                wrap_method    method wrapper
 * @param  {Function}                wrap_override  method override wrapper
 * @param  {Function}                wrap_proxy     method proxy wrapper
 * @param  {MemberBuilderValidator}  validate       member validator
 *
 * @constructor
 */
module.exports = function MemberBuilder(
    wrap_method, wrap_override, wrap_proxy, validate
)
{
    // permit omitting 'new' keyword
    if ( !( this instanceof module.exports ) )
    {
        return new module.exports(
            wrap_method, wrap_override, wrap_proxy, validate
        );
    }

    this._wrapMethod   = wrap_method;
    this._wrapOverride = wrap_override;
    this._wrapProxy    = wrap_proxy;

    this._validate = validate;
};


// we're throwing everything into the prototype
exports = module.exports.prototype;


/**
 * Initializes member object
 *
 * The member object contains members for each level of visibility (public,
 * protected and private).
 *
 * @param  {Object}  mpublic     default public members
 * @param  {Object}  mprotected  default protected members
 * @param  {Object}  mprivate    default private members
 *
 * @return  {__visobj}
 */
exports.initMembers = function( mpublic, mprotected, mprivate )
{
    return {
        'public':    mpublic    || {},
        'protected': mprotected || {},
        'private':   mprivate   || {}
    };
};


/**
 * Copies a method to the appropriate member prototype, depending on
 * visibility, and assigns necessary metadata from keywords
 *
 * @param  {__visobj}  members
 * @param  {!Object}   meta     metadata container
 * @param  {string}    name     property name
 * @param  {*}         value    property value
 *
 * @param  {!Object.<boolean>}  keywords  parsed keywords
 *
 * @param  {Function}  instCallback  function to call in order to retrieve
 *                                   object to bind 'this' keyword to
 *
 * @param  {number}   cid   class id
 * @param  {Object=}  base  optional base object to scan
 *
 * @return  {undefined}
 */
exports.buildMethod = function(
    members, meta, name, value, keywords, instCallback, cid, base
)
{
    // TODO: We can improve performance by not scanning each one individually
    // every time this method is called
    var prev_data     = scanMembers( members, name, base ),
        prev          = ( prev_data ) ? prev_data.member : null,
        prev_keywords = ( prev && prev.___$$keywords$$ ),
        dest          = getMemberVisibility( members, keywords, name );
    ;

    // ensure that the declaration is valid (keywords make sense, argument
    // length, etc)
    this._validate.validateMethod(
        name, value, keywords, prev_data, prev_keywords
    );

    // we might be overriding an existing method
    if ( keywords[ 'proxy' ] )
    {
        // TODO: Note that this is not compatible with method hiding, due to its
        // positioning (see hideMethod() below); address once method hiding is
        // implemented (the validators currently handle everything else)
        dest[ name ] = this._createProxy(
            value, instCallback, cid, name, keywords
        );
    }
    else if ( prev )
    {

        if ( keywords[ 'override' ] || prev_keywords[ 'abstract' ] )
        {
            // override the method
            dest[ name ] = this._overrideMethod(
                prev, value, instCallback, cid
            );
        }
        else
        {
            // by default, perform method hiding, even if the keyword was not
            // provided (the keyword simply suppresses the warning)
            dest[ name ] = hideMethod( prev, value, instCallback, cid );
        }

    }
    else if ( keywords[ 'abstract' ] )
    {
        // we do not want to wrap abstract methods, since they are not callable
        dest[ name ] = value;
    }
    else
    {
        // we are not overriding the method, so simply copy it over, wrapping it
        // to ensure privileged calls will work properly
        dest[ name ] = this._overrideMethod( null, value, instCallback, cid );
    }

    // store keywords for later reference (needed for pre-ES5 fallback)
    dest[ name ].___$$keywords$$ = keywords;
};


/**
 * Copies a property to the appropriate member prototype, depending on
 * visibility, and assigns necessary metadata from keywords
 *
 * @param  {__visobj}  members
 * @param  {!Object}   meta     metadata container
 * @param  {string}    name     property name
 * @param  {*}         value    property value
 *
 * @param  {!Object.<boolean>}  keywords  parsed keywords
 *
 * @param  {Object=}  base  optional base object to scan
 *
 * @return  {undefined}
 */
exports.buildProp = function( members, meta, name, value, keywords, base )
{
    // TODO: We can improve performance by not scanning each one individually
    // every time this method is called
    var prev_data     = scanMembers( members, name, base ),
        prev          = ( prev_data ) ? prev_data.member : null,
        prev_keywords = ( prev ) ? prev[ 1 ] : null;

    this._validate.validateProperty(
        name, value, keywords, prev_data, prev_keywords
    );

    getMemberVisibility( members, keywords, name )[ name ] =
        [ value, keywords ];
};


/**
 * Copies a getter/setter to the appropriate member prototype, depending on
 * visibility, and assigns necessary metadata from keywords
 *
 * TODO: This should essentially mirror buildMethod with regards to overrides,
 * proxies, etc.
 *
 * @param  {!__visobj}  members
 * @param  {!Object}    meta     metadata container
 * @param  {string}     name     getter name
 * @param  {*}          get      getter value
 * @param  {*}          set      setter value
 *
 * @param  {!Object.<boolean>}  keywords  parsed keywords
 *
 * @param  {Function}  instCallback  function to call in order to retrieve
 *                                   object to bind 'this' keyword to
 *
 * @param  {number}   cid   class id
 * @param  {Object=}  base  optional base object to scan
 *
 * @return  {undefined}
 *
 * Closure Compiler is improperly throwing warnings on Object.defineProperty():
 * @suppress {checkTypes}
 */
exports.buildGetterSetter = function(
    members, meta, name, get, set, keywords, instCallback, cid, base
)
{
    var prev_data     = scanMembers( members, name, base ),
        prev_keywords = ( ( prev_data && prev_data.get )
            ? prev_data.get.___$$keywords$$
            : null
        )
    ;

    this._validate.validateGetterSetter(
        name, {}, keywords, prev_data, prev_keywords
    );

    if ( get )
    {
        get = this._overrideMethod( null, get, instCallback, cid );

        // ensure we store the keywords *after* the override, otherwise they
        // will be assigned to the wrapped function (the getter)
        get.___$$keywords$$ = keywords;
    }

    Object.defineProperty(
        getMemberVisibility( members, keywords, name ),
        name,
        {
            get: get,
            set: ( set )
                ? this._overrideMethod( null, set, instCallback, cid )
                : set,

            enumerable:   true,
            configurable: false
        }
    );
};


/**
 * Returns member prototype to use for the requested visibility
 *
 * Will throw an exception if multiple access modifiers were used.
 *
 * @param  {__visobj} members
 *
 * @param  {!Object.<boolean>}  keywords  parsed keywords
 * @param  {string}             name      member name
 *
 * @return  {Object}  reference to visibility of members argument to use
 */
function getMemberVisibility( members, keywords, name )
{
    var viserr = function()
    {
        throw TypeError(
            "Only one access modifier may be used for definition of '" +
                name + "'"
        );
    }

    // there's cleaner ways of doing this, but consider it loop unrolling for
    // performance
    if ( keywords[ 'private' ] )
    {
        ( keywords[ 'public' ] || keywords[ 'protected' ] ) && viserr();
        return members[ 'private' ];
    }
    else if ( keywords[ 'protected' ] )
    {
        ( keywords[ 'public' ] || keywords[ 'private' ] ) && viserr();
        return members[ 'protected' ];
    }
    else
    {
        // public keyword is the default, so explicitly specifying it is only
        // for clarity
        ( keywords[ 'private' ] || keywords[ 'protected' ] ) && viserr();
        return members[ 'public' ];
    }
}


/**
 * Scan each level of visibility for the requested member
 *
 * @param  {__visobj} members
 *
 * @param  {string}   name  member to locate
 * @param  {Object=}  base  optional base object to scan
 *
 * @return  {{get,set,member}|null}
 */
function scanMembers( members, name, base )
{
    var i      = visibility.length,
        member = null;

    // locate requested member by scanning each level of visibility
    while ( i-- )
    {
        var visobj = members[ visibility[ i ] ];

        // In order to support getters/setters, we must go off of the
        // descriptor. We must also ignore base properties (last argument), such
        // as Object.prototype.toString(). However, we must still traverse the
        // prototype chain.
        if ( member = util.getPropertyDescriptor( visobj, name, true ) )
        {
            return {
                get:        member.get,
                set:        member.set,
                member:     member.value
            };
        }
    }

    // if a second comparison object was given, try again using it instead of
    // the original members object
    if ( base !== undefined )
    {
        var base_methods = base.___$$methods$$,
            base_props   = base.___$$props$$;

        // scan the base's methods and properties, if they are available
        return ( base_methods && scanMembers( base_methods, name ) )
            || ( base_props && scanMembers( base_props, name ) )
            || null
        ;
    }

    // nothing was found
    return null;
}


/**
 * Hide a method with a "new" method
 */
function hideMethod( super_method, new_method, instCallback, cid )
{
    // TODO: This function is currently unimplemented. It exists at present to
    // provide a placeholder and ensure that the override keyword is required to
    // override a parent method.
    //
    // We should never get to this point if the default validation rule set is
    // used to prevent omission of the 'override' keyword.
    throw Error(
        'Method hiding not yet implemented (we should never get here; bug).'
    );
}


/**
 * Create a method that proxies to the method of another object
 *
 * @param  {string}  proxy_to  name of property (of instance) to proxy to
 *
 * @param  {Function}  instCallback  function to call in order to retrieve
 *                                   object to bind 'this' keyword to
 *
 * @param  {number}  cid       class id
 * @param  {string}  mname     name of method to invoke on destination object
 * @param  {Object}  keywords  method keywords
 *
 * @return  {Function}  proxy method
 */
exports._createProxy = function( proxy_to, instCallback, cid, mname, keywords )
{
    return this._wrapProxy.wrapMethod(
        proxy_to, null, cid, instCallback, mname, keywords
    );
};


/**
 * Generates a method override function
 *
 * The override function simply wraps the method so that its invocation will
 * pass a __super property. This property may be used to invoke the overridden
 * method.
 *
 * @param  {function()}  super_method      method to override
 * @param  {function()}  new_method        method to override with
 *
 * @param  {Function}  instCallback  function to call in order to retrieve
 *                                   object to bind 'this' keyword to
 *
 * @param  {number}   cid  class id
 *
 * @return  {function()}  override method
 */
exports._overrideMethod = function(
    super_method, new_method, instCallback, cid
)
{
    instCallback = instCallback || function() {};

    // return a function that permits referencing the super method via the
    // __super property
    var override = null;

    // are we overriding?
    override = (
        ( super_method )
            ? this._wrapOverride
            : this._wrapMethod
        ).wrapMethod( new_method, super_method, cid, instCallback );

    // This is a trick to work around the fact that we cannot set the length
    // property of a function. Instead, we define our own property - __length.
    // This will store the expected number of arguments from the super method.
    // This way, when a method is being overridden, we can check to ensure its
    // compatibility with its super method.
    util.defineSecureProp( override,
        '__length',
        ( new_method.__length || new_method.length )
    );

    return override;
}


/**
 * Return the visibility level as a numeric value, where 0 is public and 2 is
 * private
 *
 * @param  {Object}  keywords  keywords to scan for visibility level
 *
 * @return  {number}  visibility level as a numeric value
 */
exports._getVisibilityValue = function( keywords )
{
    if ( keywords[ 'protected' ] )
    {
        return 1;
    }
    else if ( keywords[ 'private' ] )
    {
        return 2;
    }
    else
    {
        // default is public
        return 0;
    }
}

} )( module['MemberBuilder'] = {}, '.' );
/** MemberBuilderValidator **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * Validation rules for members
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 */


module.exports = exports = function MemberBuilderValidator( warn_handler )
{
    // permit omitting 'new' keyword
    if ( !( this instanceof module.exports ) )
    {
        return new module.exports( warn_handler );
    }

    this._warningHandler = warn_handler || function() {};
};


/**
 * Validates a method declaration, ensuring that keywords are valid, overrides
 * make sense, etc.
 *
 * Throws exception on validation failure
 *
 * @param  {string}  name  method name
 * @param  {*}       value method value
 *
 * @param  {Object.<string,boolean>}  keywords  parsed keywords
 *
 * @param  {Object}  prev_data      data of member being overridden
 * @param  {Object}  prev_keywords  keywords of member being overridden
 *
 * @return {undefined}
 */
exports.prototype.validateMethod = function(
    name, value, keywords, prev_data, prev_keywords
)
{
    var prev = ( prev_data ) ? prev_data.member : null;

    if ( keywords[ 'abstract' ] )
    {
        // do not permit private abstract methods (doesn't make sense, since
        // they cannot be inherited/overridden)
        if ( keywords[ 'private' ] )
        {
            throw TypeError(
                "Method '" + name + "' cannot be both private and abstract"
            );
        }
    }

    // const doesn't make sense for methods; they're always immutable
    if ( keywords[ 'const' ] )
    {
        throw TypeError(
            "Cannot declare method '" + name + "' as constant; keyword is " +
            "redundant"
        );
    }

    // virtual static does not make sense, as static methods cannot be
    // overridden
    if ( keywords[ 'virtual' ] && ( keywords[ 'static' ] ) )
    {
        throw TypeError(
            "Cannot declare static method '" + name + "' as virtual"
        );
    }

    // do not allow overriding getters/setters
    if ( prev_data && ( prev_data.get || prev_data.set ) )
    {
        throw TypeError(
            "Cannot override getter/setter '" + name + "' with method"
        );
    }

    if ( keywords[ 'proxy' ] )
    {
        // proxies are expected to provide the name of the destination object
        if ( typeof value !== 'string' )
        {
            throw TypeError(
                "Cannot declare proxy method '" + name + "'; string value " +
                    "expected"
            );
        }
        else if ( keywords[ 'abstract' ] )
        {
            // proxies are always concrete
            throw TypeError(
                "Proxy method '" + name + "' cannot be abstract"
            );
        }
    }

    // search for any previous instances of this member
    if ( prev )
    {
        // perform this check first, as it will make more sense than those that
        // follow, should this condition be satisfied
        if ( prev_keywords[ 'private' ] )
        {
            throw TypeError(
                "Private member name '" + name + "' conflicts with supertype"
            );
        }

        // disallow overriding properties with methods
        if ( !( typeof prev === 'function' ) )
        {
            throw TypeError(
                "Cannot override property '" + name + "' with method"
            );
        }

        // disallow overriding non-virtual methods
        if ( keywords[ 'override' ] && !( prev_keywords[ 'virtual' ] ) )
        {
            throw TypeError(
                "Cannot override non-virtual method '" + name + "'"
            );
        }

        // do not allow overriding concrete methods with abstract
        if ( keywords[ 'abstract' ] && !( prev_keywords[ 'abstract' ] ) )
        {
            throw TypeError(
                "Cannot override concrete method '" + name + "' with " +
                    "abstract method"
            );
        }

        // ensure parameter list is at least the length of its supertype
        if ( ( value.__length || value.length )
            < ( prev.__length || prev.length )
        )
        {
            throw TypeError(
                "Declaration of method '" + name + "' must be compatible " +
                    "with that of its supertype"
            );
        }

        // do not permit visibility deescalation
        if ( this._getVisibilityValue( prev_keywords ) <
            this._getVisibilityValue( keywords )
        )
        {
            throw TypeError(
                "Cannot de-escalate visibility of method '" + name + "'"
            );
        }

        // Disallow overriding method without override keyword (unless parent
        // method is abstract). In the future, this will provide a warning to
        // default to method hiding.
        if ( !( keywords[ 'override' ] || prev_keywords[ 'abstract' ] ) )
        {
            throw TypeError(
                "Attempting to override method '" + name +
                "' without 'override' keyword"
            );
        }
    }
    else if ( keywords[ 'override' ] )
    {
        // using the override keyword without a super method may indicate a bug,
        // but it shouldn't stop the class definition (it doesn't adversely
        // affect the functionality of the class, unless of course the method
        // attempts to reference a supertype)
        this._warningHandler( Error(
            "Method '" + name +
            "' using 'override' keyword without super method"
        ) );
    }
};


/**
 * Validates a property declaration, ensuring that keywords are valid, overrides
 * make sense, etc.
 *
 * Throws exception on validation failure
 *
 * @param  {string}  name  method name
 * @param  {*}       value method value
 *
 * @param  {Object.<string,boolean>}  keywords  parsed keywords
 *
 * @param  {Object}  prev_data      data of member being overridden
 * @param  {Object}  prev_keywords  keywords of member being overridden
 *
 * @return {undefined}
 */
exports.prototype.validateProperty = function(
    name, value, keywords, prev_data, prev_keywords
)
{
    var prev = ( prev_data ) ? prev_data.member : null;

    // do not permit visibility de-escalation
    if ( prev )
    {
        // perform this check first, as it will make more sense than those that
        // follow, should this condition be satisfied
        if ( prev_keywords[ 'private' ] )
        {
            throw TypeError(
                "Private member name '" + name + "' conflicts with supertype"
            );
        }

        // disallow overriding methods with properties
        if ( typeof prev === 'function' )
        {
            throw new TypeError(
                "Cannot override method '" + name + "' with property"
            );
        }

        if ( this._getVisibilityValue( prev_keywords )
            < this._getVisibilityValue( keywords )
        )
        {
            throw TypeError(
                "Cannot de-escalate visibility of property '" + name + "'"
            );
        }
    }

    // do not allow overriding getters/setters
    if ( prev_data && ( prev_data.get || prev_data.set ) )
    {
        throw TypeError(
            "Cannot override getter/setter '" + name + "' with property"
        );
    }

    // abstract properties do not make sense
    if ( keywords[ 'abstract' ] )
    {
        throw TypeError(
            "Property '" + name + "' cannot be declared as abstract"
        );
    }

    // constants are static
    if ( keywords[ 'static' ] && keywords[ 'const' ] )
    {
        throw TypeError(
            "Static keyword cannot be used with const for property '" +
            name + "'"
        );
    }

    // properties are inherently virtual
    if ( keywords['virtual'] )
    {
        throw TypeError( "Cannot declare property '" + name + "' as virtual" );
    }
};


/**
 * Performs common validations on getters/setters
 *
 * If a problem is found, an exception will be thrown.
 *
 * @param  {string}                   name      getter/setter name
 * @param  {Object.<string,boolean>}  keywords  parsed keywords
 *
 * @return {undefined}
 */
exports.prototype.validateGetterSetter = function(
    name, value, keywords, prev_data, prev_keywords
)
{
    var prev    = ( prev_data ) ? prev_data.member : null,
        prev_gs = ( ( prev_data && ( prev_data.get || prev_data.set ) )
            ? true
            : false
        )
    ;

    // abstract getters/setters are not yet supported
    if ( keywords[ 'abstract' ] )
    {
        throw TypeError(
            "Cannot declare getter/setter '" + name + "' as abstract"
        );
    }

    // for const getters/setters, omit the setter
    if ( keywords[ 'const' ] )
    {
        throw TypeError(
            "Cannot declare const getter/setter '" + name + "'"
        );
    }

    // virtual static does not make sense, as static methods cannot be
    // overridden
    if ( keywords[ 'virtual' ] && ( keywords[ 'static' ] ) )
    {
        throw TypeError(
            "Cannot declare static method '" + name + "' as virtual"
        );
    }

    if ( prev || prev_gs )
    {
        // perform this check first, as it will make more sense than those that
        // follow, should this condition be satisfied
        if ( prev_keywords && prev_keywords[ 'private' ] )
        {
            throw TypeError(
                "Private member name '" + name + "' conflicts with supertype"
            );
        }

        // To speed up the system we'll simply check for a getter/setter, rather
        // than checking separately for methods/properties. This is at the
        // expense of more detailed error messages. They'll live.
        if ( !( prev_gs ) )
        {
            throw TypeError(
                "Cannot override method or property '" + name +
                    "' with getter/setter"
            );
        }

        if ( !( prev_keywords && prev_keywords[ 'virtual' ] ) )
        {
            throw TypeError(
                "Cannot override non-virtual getter/setter '" + name + "'"
            );
        }

        if ( !( keywords[ 'override' ] ) )
        {
            throw TypeError(
                "Attempting to override getter/setter '" + name +
                "' without 'override' keyword"
            );
        }

        // do not permit visibility de-escalation
        if ( this._getVisibilityValue( prev_keywords || {} )
            < this._getVisibilityValue( keywords )
        )
        {
            throw TypeError(
                "Cannot de-escalate visibility of getter/setter '" + name + "'"
            );
        }
    }
    else if ( keywords[ 'override' ] )
    {
        // using the override keyword without a super method may indicate a bug
        // in the user's code
        this._warningHandler( Error(
            "Getter/setter '" + name +
            "' using 'override' keyword without super getter/setter"
        ) );
    }
}


/**
 * Return the visibility level as a numeric value, where 0 is public and 2 is
 * private
 *
 * @param  {Object}  keywords  keywords to scan for visibility level
 *
 * @return  {number}  visibility level as a numeric value
 */
exports.prototype._getVisibilityValue = function( keywords )
{
    if ( keywords[ 'protected' ] )
    {
        return 1;
    }
    else if ( keywords[ 'private' ] )
    {
        return 2;
    }
    else
    {
        // default is public
        return 0;
    }
}

} )( module['MemberBuilderValidator'] = {}, '.' );
/** VisibilityObjectFactory **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * Contains visibility object factory
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 */

/**
 * XXX: tightly coupled
 */
var util = require( __dirname + '/util' );


/**
 * Initializes visibility object factory
 *
 * The visibility object is the "magic" behind ease.js. This factory creates the
 * object that holds the varying levels of visibility, which are swapped out and
 * inherited depending on circumstance.
 *
 * @constructor
 */
module.exports = exports = function VisibilityObjectFactory()
{
    // permit omitting 'new' keyword
    if ( !( this instanceof exports ) )
    {
        // module.exports instead of exports because Closure Compiler seems to
        // be confused
        return new module.exports();
    }
};


/**
 * Sets up properties
 *
 * This includes all members (including private). Private members will be set up
 * in a separate object, so that they can be easily removed from the mix. That
 * object will include the destination object in the prototype, so that the
 * access should be transparent. This object is returned.
 *
 * Properties are expected in the following format. Note that keywords are
 * ignored:
 *     { public: { prop: [ value, { keyword: true } ] } }
 *
 * @param  {Object}   dest        destination object
 * @param  {Object}   properties  properties to copy
 * @param  {Object=}  methods     methods to copy
 *
 * @return  {Object}  object containing private members and dest as prototype
 */
exports.prototype.setup = function setup( dest, properties, methods )
{
    // create the private layer atop of the destination object
    var obj = this._createPrivateLayer( dest, properties );

    // initialize each of the properties for this instance to
    // ensure we're not sharing references to prototype values
    this._doSetup( dest, properties[ 'public' ] );

    // Do the same for protected, but only if they do not exist already in
    // public. The reason for this is because the property object is laid /atop/
    // of the public members, meaning that a parent's protected members will
    // take precedence over a subtype's overriding /public/ members. Uh oh.
    this._doSetup( dest,
        properties[ 'protected' ],
        methods[ 'protected' ],
        'public'
    );

    // then add the private parts
    this._doSetup( obj, properties[ 'private' ], methods[ 'private' ] );

    return obj;
};


/**
 * Add an extra layer atop the destination object, which will contain the
 * private members
 *
 * The object provided will be used as the prototype for the new private layer,
 * so the provided object will be accessible on the prototype chain.
 *
 * Subtypes may override this method to alter the functionality of the private
 * visibility object (e.g. to prevent it from being created).
 *
 * @param  {Object}  atop_of     object to add private layer atop of
 * @param  {Object}  properties  properties
 *
 * @return  {Object}  private layer with given object as prototype
 */
exports.prototype._createPrivateLayer = function( atop_of, properties )
{
    /** @constructor */
    var obj_ctor = function() {};
    obj_ctor.prototype = atop_of;

    // we'll be returning an instance, so that the prototype takes effect
    var obj = new obj_ctor();

    // All protected properties need to be proxied from the private object
    // (which will be passed as the context) to the object containing protected
    // values. Otherwise, the protected property values would be set on the
    // private object, making them inaccessible to subtypes.
    this.createPropProxy( atop_of, obj, properties[ 'protected' ] );

    return obj;
};


/**
 * Set up destination object by copying over properties and methods
 *
 * @param  {Object}   dest            destination object
 * @param  {Object}   properties      properties to copy
 * @param  {Object}   methods         methods to copy
 * @param  {boolean}  unless_keyword  do not set if keyword is set on existing
 *                                    method
 *
 * @return  {undefined}
 */
exports.prototype._doSetup = function(
    dest, properties, methods, unless_keyword
)
{
    var hasOwn = Array.prototype.hasOwnProperty,
        pre    = null;

    // copy over the methods
    if ( methods !== undefined )
    {
        for ( var method_name in methods )
        {
            if ( hasOwn.call( methods, method_name ) )
            {
                pre = dest[ method_name ];

                // If requested, do not copy the method over if it already
                // exists in the destination object. Don't use hasOwn here;
                // unnecessary overhead and we want to traverse any prototype
                // chains. We do not check the public object directly, for
                // example, because we need a solution that will work if a proxy
                // is unsupported by the engine.
                //
                // Also note that we need to allow overriding if it exists in
                // the protected object (we can override protected with
                // protected). This is the *last* check to ensure a performance
                // hit is incured *only* if we're overriding protected with
                // protected.
                if ( !unless_keyword
                    || ( pre === undefined )
                    || !( pre.___$$keywords$$[ unless_keyword ] )
                )
                {
                    dest[ method_name ] = methods[ method_name ];
                }
            }
        }
    }

    // initialize private/protected properties and store in instance data
    for ( var prop in properties )
    {
        if ( hasOwn.call( properties, prop ) )
        {
            dest[ prop ] = util.clone( properties[ prop ][ 0 ] );
        }
    }
}


/**
 * Creates a proxy for all given properties to the given base
 *
 * The proxy uses getters/setters to forward all calls to the base. The
 * destination object will be used as the proxy. All properties within props
 * will be used proxied.
 *
 * To summarize: for each property in props, all gets and sets will be forwarded
 * to base.
 *
 * Please note that this does not use the JS proxy implementation. That will be
 * done in the future for engines that support it.
 *
 * @param  {Object}  base   object to proxy to
 * @param  {Object}  dest   object to treat as proxy (set getters/setters on)
 * @param  {Object}  props  properties to proxy
 *
 * @return  {Object}  returns dest
 */
exports.prototype.createPropProxy = function( base, dest, props )
{
    var hasOwn = Object.prototype.hasOwnProperty;

    for ( var prop in props )
    {
        if ( !( hasOwn.call( props, prop ) ) )
        {
            continue;
        }

        ( function( prop )
        {
            // just in case it's already defined, so we don't throw an error
            dest[ prop ] = undefined;

            // public properties, when set internally, must forward to the
            // actual variable
            Object.defineProperty( dest, prop, {
                set: function( val )
                {
                    base[ prop ] = val;
                },

                get: function()
                {
                    return base[ prop ];
                },

                enumerable: true
            } );
        } ).call( null, prop );
    }

    return dest;
};

} )( module['VisibilityObjectFactory'] = {}, '.' );
/** FallbackVisibilityObjectFactory **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * Contains fallback visibility object factory
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 */


/**
 * Initializes fallback visibility object factory
 *
 * Unlike the standard visibility object, fallback does not create various
 * layers. This is for the simple fact that setting a value on one of the layers
 * is not visible to layers beneath it (its prototypes). Fallback is necessary
 * if proxy support or emulation (via ES5 getters/setters) is unavailable.
 */
module.exports = exports = function FallbackVisibilityObjectFactory()
{
    // permit omitting 'new' keyword
    if ( !( this instanceof exports ) )
    {
        // module.exports for Closure Compiler
        return new module.exports();
    }
};


/**
 * "Inherit" from VisibilityObjectFactory
 */
exports.prototype = require( __dirname + '/VisibilityObjectFactory' )();


/**
 * Do not create private visibility layer
 *
 * We're likely falling back because we cannot properly support the private
 * visibility layer. Therefore, it will be omitted.
 *
 * @param  {Object}  atop_of     will be returned, unmodified
 * @param  {Object}  properties  ignored
 *
 * @return  {Object}  provided object with no additional layer
 */
exports.prototype._createPrivateLayer = function( atop_of, properties )
{
    return atop_of;
};


/**
 * Does not create property proxy
 *
 * The fallback implementation is used because proxies are not supported and
 * cannot be emulated with getters/setters.
 *
 * @param  {Object}  base   will be returned, unmodified
 * @param  {Object}  dest   ignored
 * @param  {Object}  props  ignored
 *
 * @return  {Object}  given base
 */
exports.prototype.createPropProxy = function( base, dest, props )
{
    return base;
};

} )( module['FallbackVisibilityObjectFactory'] = {}, '.' );
/** VisibilityObjectFactoryFactory **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * Contains factory for visibility object factory
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 * @package core
 *
 * XXX: Figure out how to resolve Closure Compiler's warning about shared type
 * information
 */

// XXX: Tightly coupled
var util = require( __dirname + '/util' ),

    VisibilityObjectFactory = require( __dirname + '/VisibilityObjectFactory' ),

    FallbackVisibilityObjectFactory =
        require( __dirname + '/FallbackVisibilityObjectFactory' )
;


/**
 * Responsible for instantiating the VisibilityObjectFactory appropriate for the
 * runtime environment
 *
 * This prototype determines what class should be instantiated. If we are within
 * an ECMAScript 5 environment, we can take full advantage of the standard
 * visibility object implementation. Otherwise, we are unable to emulate proxies
 * and must fall back on a less sophisticated implementation that sacrifices
 * visibility support.
 */
exports.fromEnvironment = function()
{
    // if falling back, return fallback, otherwise standard
    return ( util.definePropertyFallback() )
        ? FallbackVisibilityObjectFactory()
        : VisibilityObjectFactory()
    ;
};

} )( module['VisibilityObjectFactoryFactory'] = {}, '.' );
/** class **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * Contains basic inheritance mechanism
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 */

var util         = require( __dirname + '/util' ),
    ClassBuilder = require( __dirname + '/ClassBuilder' ),

    warn    = require( __dirname + '/warn' ),
    Warning = warn.Warning,

    MethodWrapperFactory = require( __dirname + '/MethodWrapperFactory' ),
    wrappers             = require( __dirname + '/MethodWrappers' ).standard,

    class_builder = ClassBuilder(
        require( __dirname + '/MemberBuilder' )(
            MethodWrapperFactory( wrappers.wrapNew ),
            MethodWrapperFactory( wrappers.wrapOverride ),
            MethodWrapperFactory( wrappers.wrapProxy ),
            require( __dirname + '/MemberBuilderValidator' )(
                function( warning )
                {
                    warn.handle( Warning( warning ) );
                }
            )
        ),
        require( __dirname + '/VisibilityObjectFactoryFactory' )
            .fromEnvironment()
    )
;


/**
 * This module may be invoked in order to provide a more natural looking class
 * definition mechanism
 *
 * This may not be used to extend existing classes. To extend an existing class,
 * use the class's extend() method. If unavailable (or extending a non-ease.js
 * class/object), use the module's extend() method.
 *
 * @param  {string|Object}  namedef  optional name or definition
 * @param  {Object=}        def      class definition if first argument is name
 *
 * @return  {Function|Object}  new class or staging object
 */
module.exports = function( namedef, def )
{
    var type   = ( typeof namedef ),
        result = null
    ;

    switch ( type )
    {
        // anonymous class
        case 'object':
            result = createAnonymousClass.apply( null, arguments );
            break;

        // named class
        case 'string':
            result = createNamedClass.apply( null, arguments );
            break;

        default:
            // we don't know what to do!
            throw TypeError(
                "Expecting anonymous class definition or named class definition"
            );
    }

    return result;
};


/**
 * Creates a class, inheriting either from the provided base class or the
 * default base class
 *
 * @param  {Function|Object}  baseordfn   parent or definition object
 * @param  {Object=}          dfn         definition object if parent provided
 *
 * @return  {Function}  extended class
 */
module.exports.extend = function( baseordfn, dfn )
{
    return extend.apply( this, arguments );
};


/**
 * Implements an interface or set of interfaces
 *
 * @param  {...Function}  interfaces  interfaces to implement
 *
 * @return  {Object}  intermediate interface object
 */
module.exports.implement = function( interfaces )
{
    // implement on empty base
    return createImplement(
        null,
        Array.prototype.slice.call( arguments )
    );
};


/**
 * Determines whether the provided object is a class created through ease.js
 *
 * @param  {Object}  obj  object to test
 *
 * @return  {boolean}  true if class (created through ease.js), otherwise false
 */
module.exports.isClass = function( obj )
{
    obj = obj || {};

    return ( obj.prototype instanceof ClassBuilder.ClassBase )
        ? true
        : false
    ;
};


/**
 * Determines whether the provided object is an instance of a class created
 * through ease.js
 *
 * @param  {Object}  obj  object to test
 *
 * @return  {boolean}  true if instance of class (created through ease.js),
 *                     otherwise false
 */
module.exports.isClassInstance = function( obj )
{
    obj = obj || {};

    return ( obj instanceof ClassBuilder.ClassBase )
        ? true
        : false;
};


/**
 * Determines if the class is an instance of the given type
 *
 * The given type can be a class, interface, trait or any other type of object.
 * It may be used in place of the 'instanceof' operator and contains additional
 * enhancements that the operator is unable to provide due to prototypal
 * restrictions.
 *
 * @param  {Object}  type      expected type
 * @param  {Object}  instance  instance to check
 *
 * @return  {boolean}  true if instance is an instance of type, otherwise false
 */
module.exports.isInstanceOf = ClassBuilder.isInstanceOf;


/**
 * Alias for isInstanceOf()
 *
 * May read better in certain situations (e.g. Cat.isA( Mammal )) and more
 * accurately conveys the act of inheritance, implementing interfaces and
 * traits, etc.
 */
module.exports.isA = module.exports.isInstanceOf;


/**
 * Creates a new anonymous Class from the given class definition
 *
 * @param  {Object}  def  class definition
 *
 * @return  {Function}  new anonymous class
 */
function createAnonymousClass( def )
{
    // ensure we have the proper number of arguments (if they passed in
    // too many, it may signify that they don't know what they're doing,
    // and likely they're not getting the result they're looking for)
    if ( arguments.length > 1 )
    {
        throw Error(
            "Expecting one argument for anonymous Class definition; " +
                arguments.length + " given."
        );
    }

    return extend( def );
}


/**
 * Creates a new named Class from the given class definition
 *
 * @param  {string}  name  class name
 * @param  {Object}  def   class definition
 *
 * @return  {Function|Object}  new named class or staging object if definition
 *                             was not provided
 */
function createNamedClass( name, def )
{
    // if too many arguments were provided, it's likely that they're
    // expecting some result that they're not going to get
    if ( arguments.length > 2 )
    {
        throw Error(
            "Expecting at most two arguments for definition of named Class '" +
                name + "'; " + arguments.length + " given."
        );
    }

    // if no definition was given, return a staging object, to apply the name to
    // the class once it is actually created
    if ( def === undefined )
    {
        return createStaging( name );
    }
    // the definition must be an object
    else if ( typeof def !== 'object' )
    {
        throw TypeError(
            "Unexpected value for definition of named Class '" + name +
                "'; object expected"
        );
    }

    // add the name to the definition
    def.__name = name;

    return extend( def );
}


/**
 * Creates a staging object to stage a class name
 *
 * The class name will be applied to the class generated by operations performed
 * on the staging object. This allows applying names to classes that need to be
 * extended or need to implement interfaces.
 *
 * @param  {string}  cname  desired class name
 *
 * @return  {Object}  object staging the given class name
 */
function createStaging( cname )
{
    return {
        extend: function()
        {
            var args = Array.prototype.slice.apply( arguments );

            // extend() takes a maximum of two arguments. If only one
            // argument is provided, then it is to be the class definition.
            // Otherwise, the first argument is the supertype and the second
            // argument is the class definition. Either way you look at it,
            // the class definition is always the final argument.
            //
            // We want to add the name to the definition.
            args[ args.length - 1 ].__name = cname;

            return extend.apply( null, args );
        },

        implement: function()
        {
            // implement on empty base, providing the class name to be used once
            // extended
            return createImplement(
                null,
                Array.prototype.slice.call( arguments ),
                cname
            );
        }
    };
}


/**
 * Creates an intermediate object to permit implementing interfaces
 *
 * This object defers processing until extend() is called. This intermediate
 * object ensures that a usable class is not generated until after extend() is
 * called, as it does not make sense to create a class without any
 * body/definition.
 *
 * @param  {Object}   base    base class to implement atop of, or null
 * @param  {Array}    ifaces  interfaces to implement
 * @param  {string=}  cname   optional class name once extended
 *
 * @return  {Object}  intermediate implementation object
 */
function createImplement( base, ifaces, cname )
{
    // Defer processing until after extend(). This also ensures that implement()
    // returns nothing usable.
    return {
        extend: function()
        {
            var args     = Array.prototype.slice.call( arguments ),
                def      = args.pop(),
                ext_base = args.pop()
            ;

            // if any arguments remain, then they likely misunderstood what this
            // method does
            if ( args.length > 0 )
            {
                throw Error(
                    "Expecting no more than two arguments for extend()"
                );
            }

            // if a base was already provided for extending, don't allow them to
            // give us yet another one (doesn't make sense)
            if ( base && ext_base )
            {
                throw Error(
                    "Cannot override parent " + base.toString() + " with " +
                    ext_base.toString() + " via extend()"
                );
            }

            // if a name was provided, use it
            if ( cname )
            {
                def.__name = cname;
            }

            // If a base was provided when createImplement() was called, use
            // that. Otherwise, use the extend() base passed to this function.
            // If neither of those are available, extend from an empty class.
            ifaces.push( base || ext_base || extend( {} ) );

            return extend.call( null,
                implement.apply( this, ifaces ),
                def
            );
        }
    };
}


/**
 * Mimics class inheritance
 *
 * This method will mimic inheritance by setting up the prototype with the
 * provided base class (or, by default, Class) and copying the additional
 * properties atop of it.
 *
 * The class to inherit from (the first argument) is optional. If omitted, the
 * first argument will be considered to be the properties list.
 *
 * @param  {Function|Object}  _   parent or definition object
 * @param  {Object=}          __  definition object if parent was provided
 *
 * @return  {Function}  extended class
 */
function extend( _, __ )
{
    // set up the new class
    var new_class = class_builder.build.apply( class_builder, arguments );

    // set up some additional convenience props
    setupProps( new_class );

    // lock down the new class (if supported) to ensure that we can't add
    // members at runtime
    util.freeze( new_class );

    return new_class;
}


/**
 * Implements interface(s) into an object
 *
 * This will copy all of the abstract methods from the interface and merge it
 * into the given object.
 *
 * @param  {Object}       baseobj     base object
 * @param  {...Function}  interfaces  interfaces to implement into dest
 *
 * @return  {Object}  destination object with interfaces implemented
 */
var implement = function( baseobj, interfaces )
{
    var args = Array.prototype.slice.call( arguments ),
        dest = {},
        base = args.pop(),
        len  = args.length,
        arg  = null,

        implemented   = [],
        make_abstract = false
    ;

    // add each of the interfaces
    for ( var i = 0; i < len; i++ )
    {
        arg = args[ i ];

        // copy all interface methods to the class (does not yet deep copy)
        util.propParse( arg.prototype, {
            method: function( name, func, is_abstract, keywords )
            {
                dest[ 'abstract ' + name ] = func.definition;
                make_abstract = true;
            }
        } );
        implemented.push( arg );
    }

    // xxx: temporary
    if ( make_abstract )
    {
        dest.___$$abstract$$ = true;
    }

    // create a new class with the implemented abstract methods
    var class_new = module.exports.extend( base, dest );
    ClassBuilder.getMeta( class_new ).implemented = implemented;

    return class_new;
}


/**
 * Sets up common properties for the provided function (class)
 *
 * @param  {function()}  func  function (class) to set up
 *
 * @return  {undefined}
 */
function setupProps( func )
{
    attachExtend( func );
    attachImplement( func );
}


/**
 * Attaches extend method to the given function (class)
 *
 * @param  {Function}  func  function (class) to attach method to
 *
 * @return  {undefined}
 */
function attachExtend( func )
{
    /**
     * Shorthand for extending classes
     *
     * This method can be invoked on the object, rather than having to call
     * Class.extend( this ).
     *
     * @param  {Object}  props  properties to add to extended class
     *
     * @return  {Object}  extended class
     */
    util.defineSecureProp( func, 'extend', function( props )
    {
        return extend( this, props );
    });
}


/**
 * Attaches implement method to the given function (class)
 *
 * Please see the implement() export of this module for more information.
 *
 * @param  {function()}  func  function (class) to attach method to
 *
 * @return  {undefined}
 */
function attachImplement( func )
{
    util.defineSecureProp( func, 'implement', function()
    {
        return createImplement(
            func,
            Array.prototype.slice.call( arguments )
        );
    });
}

} )( module['class'] = {}, '.' );
/** class_final **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * Wrapper permitting the definition of final classes
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 */

var Class = require( __dirname + '/class' );


/**
 * Creates a final class
 *
 * @return  {Function}  final class
 */
exports = module.exports = function()
{
    markFinal( arguments );

    // forward everything to Class
    var result = Class.apply( this, arguments );

    if ( !Class.isClass( result ) )
    {
        finalOverride( result );
    }

    return result;
};


/**
 * Creates a final class from a class extend operation
 *
 * @return  {Function}  final class
 */
exports.extend = function()
{
    markFinal( arguments );
    return Class.extend.apply( this, arguments );
};


/**
 * Causes a definition to be flagged as final
 *
 * This function assumes the last argument to be the definition, which is the
 * common case, and modifies the object referenced by that argument.
 *
 * @param  {!Arguments}  args  arguments to parse
 *
 * @return  {undefined}
 */
function markFinal( args )
{
    // the last argument _should_ be the definition
    var dfn = args[ args.length - 1 ];

    if ( typeof dfn === 'object' )
    {
        // mark as abstract
        dfn.___$$final$$ = true;
    }
}


/**
 * Overrides object members to permit final classes
 *
 * @param  {Object}  obj  object to override
 *
 * @return  {undefined}
 */
function finalOverride( obj )
{
    var extend = obj.extend;

    // wrap extend, applying the abstract flag
    obj.extend = function()
    {
        markFinal( arguments );
        return extend.apply( this, arguments );
    };
}

} )( module['class_final'] = {}, '.' );
/** FallbackMemberBuilder **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * Handles building members (properties, methods) in a pre-ES5 environment
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 */

/**
 * Supertype
 */
var MemberBuilder = require( __dirname + '/MemberBuilder' );

/**
 * Responsible for building class members
 */
module.exports = exports = function FallbackMemberBuilder(
    wrap_method, wrap_override
)
{
    // permit omitting 'new' keyword
    if ( !( this instanceof module.exports ) )
    {
        return new module.exports( wrap_method, wrap_override );
    }

    // invoke parent constructor
    module.exports.prototype.constructor.call( this,
        wrap_method, wrap_override
    );
};

// inherit from MemberBuilder
module.exports.prototype   = new MemberBuilder();
module.exports.constructor = module.exports;


/**
 * Getters/setters are unsupported in a pre-ES5 environment
 *
 * Simply throw an exception, as it clearly represents that the developer did
 * not account for the possibility that their software may have been executed in
 * a pre-ES5 environment.
 */
exports.prototype.buildGetterSetter = function()
{
    throw Error( 'Getters/setters are unsupported in this environment' );
};
} )( module['FallbackMemberBuilder'] = {}, '.' );
/** interface **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * Contains interface module
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 */

var util           = require( __dirname + '/util' ),

    MethodWrapperFactory = require( __dirname + '/MethodWrapperFactory' ),
    wrappers             = require( __dirname + '/MethodWrappers' ).standard,

    member_builder = require( __dirname + '/MemberBuilder' )(
        MethodWrapperFactory( wrappers.wrapNew ),
        MethodWrapperFactory( wrappers.wrapOverride ),
        MethodWrapperFactory( wrappers.wrapProxy ),
        require( __dirname + '/MemberBuilderValidator' )()
    ),

    Class = require( __dirname + '/class' )
;


/**
 * This module may be invoked in order to provide a more natural looking
 * interface definition
 *
 * Only new interfaces may be created using this method. They cannot be
 * extended. To extend an existing interface, call its extend() method, or use
 * the extend() method of this module.
 *
 * @param  {string|Object}  namedef  optional name or definition
 * @param  {Object=}        def      interface definition if first arg is name
 *
 * @return  {Function|Object}  new interface or staging object
 */
module.exports = function( namedef, def )
{
    var type   = ( typeof namedef ),
        result = null
    ;

    switch ( type )
    {
        // anonymous interface
        case 'object':
            result = createAnonymousInterface.apply( null, arguments );
            break;

        // named class
        case 'string':
            result = createNamedInterface.apply( null, arguments );
            break;

        default:
            // we don't know what to do!
            throw TypeError(
                "Expecting anonymous interface definition or named " +
                    "interface definition"
            );
    }

    return result;
};


/**
 * Creates an interface
 *
 * @return  {Function}  extended interface
 */
module.exports.extend = function()
{
    return extend.apply( this, arguments );
};


/**
 * Determines whether the provided object is an interface created through
 * ease.js
 *
 * @param  {Object}  obj  object to test
 *
 * @return  {boolean}  true if interface (created through ease.js), otherwise
 *                     false
 */
module.exports.isInterface = function( obj )
{
    obj = obj || {};

    return ( obj.prototype instanceof Interface )
        ? true
        : false
    ;
};


/**
 * Default interface implementation
 *
 * @return  {undefined}
 */
function Interface() {}


/**
 * Creates a new anonymous Interface from the given interface definition
 *
 * @param  {Object}  def  interface definition
 *
 * @return  {Function}  new anonymous interface
 */
function createAnonymousInterface( def )
{
    // ensure we have the proper number of arguments (if they passed in
    // too many, it may signify that they don't know what they're doing,
    // and likely they're not getting the result they're looking for)
    if ( arguments.length > 1 )
    {
        throw Error(
            "Expecting one argument for Interface definition; " +
                arguments.length + " given."
        );
    }

    return extend( def );
}


/**
 * Creates a new named interface from the given interface definition
 *
 * @param  {string}  name  interface name
 * @param  {Object}  def   interface definition
 *
 * @return  {Function}  new named interface
 */
function createNamedInterface( name, def )
{
    // if too many arguments were provided, it's likely that they're
    // expecting some result that they're not going to get
    if ( arguments.length > 2 )
    {
        throw Error(
            "Expecting two arguments for definition of named Interface '" +
                name + "'; " + arguments.length + " given."
        );
    }

    // the definition must be an object
    if ( typeof def !== 'object' )
    {
        throw TypeError(
            "Unexpected value for definition of named Interface '" +
                name + "'; object expected"
        );
    }

    // add the name to the definition
    def.__name = name;

    return extend( def );
}


var extend = ( function( extending )
{
    return function extend()
    {
        // ensure we'll be permitted to instantiate interfaces for the base
        extending = true;

        var args      = Array.prototype.slice.call( arguments ),
            props     = args.pop() || {},
            base      = args.pop() || Interface,
            prototype = new base(),
            iname     = '',

            members = member_builder.initMembers(
                prototype, prototype, prototype
            )
        ;

        // grab the name, if one was provided
        if ( iname = props.__name )
        {
            // we no longer need it
            delete props.__name;
        }

        // sanity check
        inheritCheck( prototype );

        var new_interface = createInterface( iname );

        try
        {
            util.propParse( props, {
                assumeAbstract: true,

                property: function()
                {
                    // should never get to this point because of assumeAbstract
                    throw TypeError( 'Unexpected internal error' );
                },

                getset: function()
                {
                    // should never get to this point because of assumeAbstract
                    throw TypeError( 'Unexpected internal error' );
                },

                method: function( name, value, is_abstract, keywords )
                {
                    // all members must be public
                    if ( keywords[ 'protected' ] || keywords[ 'private' ] )
                    {
                        throw TypeError(
                            iname + " member " + name + " must be public"
                        );
                    }

                    member_builder.buildMethod(
                        members, null, name, value, keywords
                    );
                }
            } );
        }
        catch ( e )
        {
            // alter the message to include our name
            e.message = "Failed to define interface " +
                ( ( iname ) ? iname : '(anonymous)' ) + ": " + e.message
            ;

            // re-throw
            throw e;
        }

        attachExtend( new_interface );
        attachStringMethod( new_interface, iname );

        new_interface.prototype   = prototype;
        new_interface.constructor = new_interface;

        // freeze the interface (preventing additions), if supported
        util.freeze( new_interface );

        // we're done; let's not allow interfaces to be instantiated anymore
        extending = false;

        return new_interface;
    };


    /**
     * Creates a new interface constructor function
     *
     * @param  {string=}  iname  interface name
     *
     * @return  {function()}
     */
    function createInterface( iname )
    {
        return function()
        {
            // allows us to extend the interface without throwing an exception
            // (since the prototype requires an instance)
            if ( !extending )
            {
                // only called if someone tries to create a new instance of an
                // interface
                throw Error(
                    "Interface" + ( ( iname ) ? ( iname + ' ' ) : '' ) +
                        " cannot be instantiated"
                );
            }
        };
    }
} )( false );


/**
 * Assures that the parent object is a valid object to inherit from
 *
 * This method allows inheriting from any object (note that it will likely cause
 * errors if not an interface), but will place restrictions on objects like
 * Classes that do not make sense to inherit from. This will provide a more
 * friendly error, with suggestions on how to resolve the issue, rather than a
 * cryptic error resulting from inheritance problems.
 *
 * This method will throw an exception if there is a violation.
 *
 * @param  {Object}  prototype  prototype to check for inheritance flaws
 *
 * @return  {undefined}
 */
function inheritCheck( prototype )
{
    // if we're inheriting from another interface, then we're good
    if ( !( prototype instanceof Interface ) )
    {
        throw new TypeError( "Interfaces may only extend other interfaces" );
    }
}


/**
 * Attaches extend method to the given function (interface)
 *
 * @param  {Function}  func  function (interface) to attach method to
 *
 * @return  {undefined}
 */
function attachExtend( func )
{
    /**
     * Shorthand for extending interfaces
     *
     * This method can be invoked on the object, rather than having to call
     * Interface.extend( this ).
     *
     * @param  {Object}  props  properties to add to extended interface
     *
     * @return  {Object}  extended interface
     */
    util.defineSecureProp( func, 'extend', function( props )
    {
        return extend( this, props );
    });
}


/**
 * Provides more sane/useful output when interface is converted to a string
 *
 * @param  {Object}   func   interface
 * @param  {string=}  iname  interface name
 *
 * @return  {undefined}
 */
function attachStringMethod( func, iname )
{
    func.toString = ( iname )
        ? function() { return '[object Interface <' + iname + '>]'; }
        : function() { return '[object Interface]'; }
    ;
}

} )( module['interface'] = {}, '.' );
/** class_abstract **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * Wrapper permitting the definition of abstract classes
 *
 * This doesn't actually introduce any new functionality. Rather, it sets a flag
 * to allow abstract methods within a class, forcing users to clearly state
 * that a class is abstract.
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 */

var Class = require( __dirname + '/class' );


/**
 * Creates an abstract class
 *
 * @return  {Function}  abstract class
 */
module.exports = exports = function()
{
    markAbstract( arguments );

    // forward everything to Class
    var result = Class.apply( this, arguments );

    // if we're using the temporary object, then override its methods to permit
    // abstract classes
    if ( !Class.isClass( result ) )
    {
        abstractOverride( result );
    }

    return result;
};


/**
 * Creates an abstract class from a class extend operation
 *
 * @return  {Function}  abstract class
 */
exports.extend = function()
{
    markAbstract( arguments );
    return Class.extend.apply( this, arguments );
};


/**
 * Creates an abstract class implementing the given members
 *
 * Simply wraps the class module's implement() method.
 *
 * @return  {Object}  abstract class
 */
exports.implement = function()
{
   var impl = Class.implement.apply( this, arguments );

    abstractOverride( impl );
    return impl;
};


/**
 * Causes a definition to be flagged as abstract
 *
 * This function assumes the last argument to be the definition, which is the
 * common case, and modifies the object referenced by that argument.
 *
 * @param  {Arguments}  args  arguments to parse
 *
 * @return  {undefined}
 */
function markAbstract( args )
{
    // the last argument _should_ be the definition
    var dfn = args[ args.length - 1 ];

    if ( typeof dfn === 'object' )
    {
        // mark as abstract
        dfn.___$$abstract$$ = true;
    }
}


/**
 * Overrides object members to permit abstract classes
 *
 * @param  {Object}  obj  object to override
 *
 * @return  {Object}  obj
 */
function abstractOverride( obj )
{
    var extend = obj.extend,
        impl   = obj.implement;

    // wrap and apply the abstract flag, only if the method is defined (it may
    // not be under all circumstances, e.g. after an implement())
    impl && ( obj.implement = function()
    {
        return abstractOverride( impl.apply( this, arguments ) );
    } );

    // wrap extend, applying the abstract flag
    obj.extend = function()
    {
        markAbstract( arguments );
        return extend.apply( this, arguments );
    };

    return obj;
}

} )( module['class_abstract'] = {}, '.' );
/** version **/
( function( module, __dirname )
{
    var exports = module.exports = {};
/**
 * Provides version information
 *
 *  Copyright (C) 2010,2011 Mike Gerwitz
 *
 *  This file is part of ease.js.
 *
 *  ease.js is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author  Mike Gerwitz
 */

/*** DO NOT MODIFY; generated by verset ***/

var major  = 0,
    minor  = 2,
    rev    = 0,
    suffix = 'dev',

    version = [ major, minor, rev, suffix ];

version.major  = major;
version.minor  = minor;
version.rev    = rev;
version.suffix = suffix;

version.toString = function()
{
    return this.join( '.' )
        .replace( /\.([^.]+)$/, '-$1' )
        .replace( /-$/, '' );
};

module.exports = version;
} )( module['version'] = {}, '.' );

    // the following should match the exports of /index.js
    ns_exports.Class         = module['class'].exports;
    ns_exports.AbstractClass = module['class_abstract'].exports;
    ns_exports.FinalClass    = module['class_final'].exports;
    ns_exports.Interface     = module['interface'].exports;
    ns_exports.version       = module['version'].exports;
} )( easejs );