/**
 * Concrete PostRestDataApiStrategy class
 *
 *  Copyright (C) 2017 LoVullo Associates, Inc.
 *
 *  This file is part of the Liza Data Collection Framework.
 *
 *  liza is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

var Class               = require( 'easejs' ).Class,
    RestDataApiStrategy = require( './RestDataApiStrategy' ),

    // XXX: decouple (this couples us to the client)!
    HttpDataProxy = require( '../client/proxy/HttpDataProxy' );


/**
 * Requests data from a RESTful service, POSTing arguments
 */
module.exports = Class( 'PostRestDataApiStrategy' )
    .implement( RestDataApiStrategy )
    .extend(
{
    /**
     * Data proxy used to communicate with the service
     * @type {HttpDataProxy}
     */
    'private _proxy': null,


    /**
     * Initialize strategy
     *
     * The strategy is independent of any URL; that is, we should not pass the
     * URL here, as the strategy can be re-used for *any* RESTful service.
     *
     * @param {HttpDataProxy} data_proxy proxy to handle all requests
     */
    __construct: function( data_proxy )
    {
        if ( !( Class.isA( HttpDataProxy, data_proxy ) ) )
        {
            throw Error(
                'Expected HttpDataProxy; given ' + data_proxy
            );
        }

        this._proxy = data_proxy;
    },


    /**
     * Request data from the service
     *
     * @param {string}           url      service URL
     * @param {Object}           data     request params
     * @param {function(Object)} callback server response callback
     *
     * @return {RestDataApi} self
     */
    'public requestData': function( url, data, callback )
    {
        this._proxy.post( url, data, function( retdata )
        {
            callback( retdata );
        } );

        return this;
    }
} );