/**
 * Test case for MemoryStore
 *
 *  Copyright (C) 2010-2019 R-T Specialty, LLC.
 *
 *  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/>.
 */

"use strict";

var store  = require( '../../' ).store,
    chai   = require( 'chai' ),
    expect = chai.expect,
    Class  = require( 'easejs' ).Class,
    Trait  = require( 'easejs' ).Trait,
    Sut    = store.MemoryStore;

chai.use( require( 'chai-as-promised' ) );


describe( 'store.MemoryStore', () =>
{
    describe( '#add', () =>
    {
        it( 'adds item to store when missing', () =>
        {
            const sut  = Sut();
            const item = {};

            return expect(
                sut.add( 'foo', item )
                    .then( () => sut.get( 'foo' ) )
            ).to.eventually.equal( item );
        } );


        it( 'replaces item in store if existing', () =>
        {
            const sut  = Sut();
            const item = {};

            return expect(
                sut.add( 'foo', [] )
                    .then( () => sut.add( 'foo', item ) )
                    .then( () => sut.get( 'foo' ) )
            ).to.eventually.equal( item );
        } );


        it( 'returns self with promise', () =>
        {
            const sut = Sut();

            return expect(
                sut.add( 'foo', 'bar' )
            ).to.eventually.equal( sut );
        } );
    } );


    describe( '#populate', () =>
    {
        it( "#add's each element of object to store", () =>
        {
            const obj = { foo: {}, bar: {} };
            const sut = Sut();

            return sut.populate( obj )
                .then( ps =>
                {
                    // by reference
                    expect( sut.get( 'foo' ) )
                        .to.eventually.equal( obj.foo );
                    expect( sut.get( 'bar' ) )
                        .to.eventually.equal( obj.bar );

                    expect( ps.length )
                       .to.equal( Object.keys( obj ).length );
                } );
        } );

        it( "fails if any add fails", () =>
        {
            const e = Error( 'ok' );

            const sut = Sut.extend( {
                'override add': ( k, v ) => Promise.reject( e )
            } )();

            return expect( sut.populate( { a: 1 } ) )
                .to.eventually.be.rejectedWith( e );
        } );
    } );


    // most things implicitly tested above
    describe( '#get', () =>
    {
        it( 'rejects promise if store item does not exist', () =>
        {
            return expect( Sut().get( 'unknown' ) )
                .to.eventually.be.rejected
                .and.be.instanceof( store.StoreMissError );
        } );
    } );


    describe( '#clear', () =>
    {
        it( 'removes all items from store', () =>
        {
            const sut  = Sut();
            const keys = [ 'foo', 'bar', 'baz' ];

            keys.forEach( key => sut.add( key ) );

            // should remove all items
            return sut.clear().then( () =>
            {
                return Promise.all(
                    keys.map( key => {
                        expect( sut.get( key ) )
                            .to.eventually.be.rejected
                    } )
                );
            } );
        } );


        it( 'returns self with promise', () =>
        {
            const sut = Sut();

            return expect(
                sut.clear()
            ).to.eventually.equal( sut );
        } );
    } );


    describe( 'with mixin', () =>
    {
        it( 'allows overriding #add', done =>
        {
            const expected_key   = 'foo';
            const expected_value = {};

            Sut.use(
                Trait.extend( Sut,
                {
                    'override add'( key, value )
                    {
                        expect( key ).to.equal( expected_key );
                        expect( value ).to.equal( expected_value );
                        done();
                    }
                } )
            )().add( expected_key, expected_value );
        } );


        it( "allows overriding #populate", () =>
        {
            const obj  = {};
            let called = false;

            return Sut.use(
                Trait.extend( Sut,
                {
                    'override populate'( given )
                    {
                        expect( given ).to.equal( obj );
                        called = true;

                        return Promise.resolve( true );
                    }
                } )
            )().populate( obj )
                .then( () => expect( called ).to.equal( true ) );
        } );


        it( 'allows overriding #get', done =>
        {
            const expected_key = 'bar';

            Sut.use(
                Trait.extend( Sut,
                {
                    'override get'( key )
                    {
                        expect( key ).to.equal( expected_key );
                        done();
                    }
                } )
            )().get( expected_key );
        } );


        it( 'allows overriding #clear', done =>
        {
            Sut.use(
                Trait.extend( Sut,
                {
                    'override clear'( key )
                    {
                        done();
                    }
                } )
            )().clear();
        } );
    } );


    describe( '#reduce', () =>
    {
        it( 'folds each stored item', () =>
        {
            const StubSut = Sut.extend(
            {
                sum()
                {
                    return this.reduce(
                        ( accum, item, key ) =>
                        {
                            // correct key for item?
                            expect( item ).to.equal( vals[ key ] );

                            return accum + item;
                        },
                        5
                    );
                }
            } );

            const sut  = StubSut();
            const vals = {
                one:   1,
                two:   2,
                three: 3,
            };

            Object.keys( vals ).forEach(
                ( key, i ) => sut.add( key, vals[ key ] )
            );

            // implicitly tests initial
            return expect( sut.sum() )
                to.equal( 11 );
        } );
    } );
} );