Source: data-source/collection-search.js

/**
 Class created dynamically by dataSource.JSONArray.
 It is used to search and filter data in a collection.
 @namespace ludo.dataSource
 @class ludo.dataSource.JSONArraySearch
 @param {object} config
 @param {object} config.delay  Delay in seconds between call to search and execution of search.
 A delay is useful when using text fields to search. Default : 0
 @param {Array} config.index Columns in datasource to index for search
 @fires ludo.dataSource.JSONArraySearch#initSearch Fired just before search starts
 @fires ludo.dataSource.JSONArraySearch#search Fired when search is finished
 @fires ludo.dataSource.JSONArraySearch#deleteSearch
 */
ludo.dataSource.JSONArraySearch = new Class({
	Extends:ludo.Core,
	dataSource:undefined,
	searchResult:undefined,
	searchIndexCreated:false,

	delay:0,
	searches:undefined,
	searchBranches:undefined,
	searchFn:undefined,
	currentBranch:undefined,

	index:undefined,

	searchParser:undefined,

	__construct:function (config) {
		this.parent(config);
        this.setConfigParams(config, ['dataSource','index','delay']);
		this.searchParser = new ludo.dataSource.SearchParser();
		this.clear();
	},

	ludoEvents:function () {
		this.parent();
		if(!this.dataSource.hasRemoteSearch()){
			this.dataSource.addEvent('beforeload', this.clearSearchIndex.bind(this));
			this.dataSource.addEvent('beforeload', this.deleteSearch.bind(this));
			this.dataSource.addEvent('update', this.clearSearchIndex.bind(this));
			this.dataSource.addEvent('delete', this.onDelete.bind(this));
		}
	},
	/**
	 * execute a text search
	 * @function Search
	 * @param {String} search
	 * @memberof ludo.dataSource.JSONArraySearch.prototype
	 */
	search:function (search) {
		if (!search && this.searches.length == 0)return;
		this.clear();
		this.where(search);
		this.endBranch();

		var delay = this.getSearchDelay();
		if (delay === 0) {
			this.executeSearch(this.searches[0].txt);
		} else {
			this.executeSearch.delay(delay * 1000, this, this.searches[0].txt);
		}
	},

	executeSearch:function (searchTerm) {
		if (searchTerm == this.searches[0].txt) {
			this.execute();
		}
	},

	/**
	 Clear all search terms and search functions
	 @function clear
	 @chainable
	 @return {dataSource.JSONArraySearch} this
	 @memberof ludo.dataSource.JSONArraySearch.prototype
	 */
	clear:function () {
		this.searches = [];
		return this;
	},

	/**
	 * Delete search terms/functions and dispose search result. This method will fire a deleteSearch event which
	 * {{#crossLink "dataSource.JSONArray"}}{{/crossLink}} listens to. It will trigger an update of
	 * views using the {{#crossLink "dataSource.JSONArray"}}{{/crossLink}} object as dataSource.
	 * @function deleteSearch
	 * @memberof ludo.dataSource.JSONArraySearch.prototype
	 */
	deleteSearch:function () {
		this.fireEvent('deleteSearch');
		this.searchResult = undefined;
		this.clear();
	},
	/**
	 Start building a new search
	 @function where
	 @param {String|Function} search
	 @return {dataSource.JSONArraySearch} this
	 @memberof ludo.dataSource.JSONArraySearch.prototype
	 @chainable
	 @example
		 var searcher = ludo.get('idOfDataSearch').getSearcher();
		 searcher.where('Portugal').or('Norway').execute();
	 will find all records where the search index matches 'Portugal' or 'Norway' (case insensitive).
	 By default, the entire record is indexed. Custom indexes can be created by defining
	 index using the "index" constructor attribute.
	 @example
	 	searcher.where(function(record){
	 		return parseInt(record.price) < 100
	 	});
	 is example of a function search. On {{#crossLink "dataSource.JSONArray/execute"}}{{/crossLink}} this
	 function will be called for each record. It should return true if match is found, false otherwise.
	 The function above will return true for all records where the value of record.price is less than 100.
	 */
	where:function (search) {
		this.clear();
		this.appendSearch(Array.from(arguments));
		return this;
	},

	/**
	 OR search
	 @function or
	 @param {String|Function} search
	 @return {dataSource.JSONArraySearch} this
	 @memberof ludo.dataSource.JSONArraySearch.prototype
	 @chainable
	 @example
		 var searcher = myDataSource.getSearcher();
		 var populationFn = function(record){
					return record.population > 1000000 ? true: false;
				}
		 searcher.where('Europe').or(populationFn).execute();

	 Finds all records where 'Europe' is in the text or population is greater than 1
	 million.
	 */
	or:function (search) {
		this.appendOperator('|');
		this.appendSearch(Array.from(arguments));
		return this;
	},

	appendSearch:function (args) {
		this.preCondition(args);
		var search = this.getActualArgument(args);
        var searchObject;
		if (typeof search === 'function') {
			searchObject = { fn:search };
		} else {
			searchObject = { txt:search.toLowerCase() };
		}
		this.searches.push(searchObject);
		this.postCondition(args);
	},

	/**
	 AND search
	 @function and
	 @param {String|Function} search
	 @return {dataSource.JSONArraySearch} this
	 @chainable
	 @memberof ludo.dataSource.JSONArraySearch.prototype
	 @example
		 var searcher = myDataSource.getSearcher();
		 var populationFn = function(record){
					return record.population > 1000000 ? true: false;
				}
		 searcher.where('Europe').and(populationFn).execute();
	 Finds all records where 'Europe' is in the text and population is greater than 1
	 million.
	 */
	and:function (search) {
		this.appendOperator('&');
		this.appendSearch(Array.from(arguments));
		return this;
	},

	preCondition:function (args) {
		if (args.length == 2 && args[0] === '(') {
			this.branch();
		}
	},

	postCondition:function (args) {
		if (args.length == 2 && args[1] === ')') {
			this.endBranch();
		}
	},

	getActualArgument:function (args) {
		if (args.length === 2) {
			if (args[0] == ')' || args[0] == '(') {
				return args[1];
			}
			return args[0];
		}
		return args[0];
	},


	/**
	 * Search for match in one of the items
	 * @function withIn
	 * @param {Array} searches
	 * @chainable
	 * @memberof ludo.dataSource.JSONArraySearch.prototype
	 * @return {dataSource.JSONArraySearch} this
	 */
	withIn:function (searches) {
		for (var i = 0; i < searches.length; i++) {
			this.or(searches[i]);
		}
		return this;
	},

	/**
	 * Start grouping search items together
	 * @function branch
	 * @chainable
	 * @memberof ludo.dataSource.JSONArraySearch.prototype
	 * @return {dataSource.JSONArraySearch} this
	 */
	branch:function () {
		this.appendOperator('(');
		return this;
	},
	/**
	 * Close group of search items.
	 * @function branch
	 * @chainable
	 * @memberof ludo.dataSource.JSONArraySearch.prototype
	 * @return {endBranch.CollectionSearch} this
	 */
	endBranch:function () {
		this.appendOperator(')');
		return this;
	},

	appendOperator:function (operator) {
		if (operator != '(' && this.searches.length == 0)return;
		if (operator === '|' && this.searches.getLast() === '(')return;
		this.searches.push(operator);
	},
	/**
	 Execute a search based on current search terms
	 @function execute
	 @chainable
	 @return {dataSource.JSONArraySearch} this
	 @memberof ludo.dataSource.JSONArraySearch.prototype
	 @example
		 // Assumes that ludo.get('collection') returns a {{#crossLink "dataSource.JSONArray"}}{{/crossLink}} object
		 var searcher = ludo.get('collection').getSearcher();
		 searcher.clear();
		 searcher.where('Oslo').or('Moscow');
		 searcher.execute();
	 */
	execute:function () {
		if (!this.searchIndexCreated) {
			this.createSearchIndex();
		}
		if (!this.hasSearchTokens()) {
			this.deleteSearch();
		} else {
            this.fireEvent('initSearch');
			this.searchResult = [];
			this.compileSearch();
            this.performSearch();
		}

		this.fireEvent('search');
		return this;
	},

    performSearch:function(){
        var data = this.getDataFromSource();
        for (var i = 0; i < data.length; i++) {
            if (this.isMatchingSearch(data[i])) {
                this.searchResult.push(data[i]);
            }
        }
    },

	isMatchingSearch:function (record) {
		return this.searchFn.call(this, record);
	},

	compileSearch:function () {
		this.searchFn = this.searchParser.getSearchFn(this.searches);
	},

	/**
	 * Returns true if search terms or search functions exists.
	 * @function hasSearchTokens
	 * @memberof ludo.dataSource.JSONArraySearch.prototype
	 * @return {Boolean}
	 */
	hasSearchTokens:function () {
		return this.hasContentInFirstSearch() || this.searches.length > 1;
	},

	hasContentInFirstSearch:function () {
		if (this.searches.length === 0)return false;
		var s = this.searches[0];
		return (ludo.util.isArray(s) || s.fn !== undefined || (s.txt !== undefined && s.txt.length > 0));
	},

	/**
	 * Returns true when<br>
	 *     - zero or more records are found in search result<br>
	 * Returns false when<br>
	 *  - search result is undefined because no search has been executed or search has been deleted.
	 * @function hasData
	 * @memberof ludo.dataSource.JSONArraySearch.prototype
	 * @return {Boolean}
	 */
	hasData:function () {
		return this.searchResult !== undefined;
	},

	getData:function () {
		return this.searchResult;
	},

	getDataFromSource:function () {
		return this.dataSource.getLinearData();
	},

	getSearchDelay:function () {
		return this.delay || 0;
	},

	onDelete:function(record){
		if(this.searchResult && this.searchResult.length > 0){
			for(var i=0;i<this.searchResult.length-1;i++){
				var rec = this.searchResult[i];
				if(rec.uid == record.uid){
					this.clearSearchIndex();
					this.searchResult.splice(i, 1);
					console.log(this.searchResult.length);
				}
			}
		}

	},

	clearSearchIndex:function () {
		this.searchIndexCreated = false;
	},

	createSearchIndex:function () {
		this.indexBranch(this.getDataFromSource());
		this.searchIndexCreated = true;
	},

    indexBranch:function(data, parents){
		parents = parents || [];
        var keys = this.getSearchIndexKeys();

        var index;
        for (var i = 0; i < data.length; i++) {
            index = [];
            for (var j = 0; j < keys.length; j++) {
                if (data[i][keys[j]] !== undefined) {
                    index.push((data[i][keys[j]] + '').toLowerCase());
                }
            }
            data[i].searchIndex = index.join(' ');

			for(j=0;j<parents.length;j++){
				parents[j].searchIndex = [parents[j].searchIndex, data[i].searchIndex].join(' ');

			}
            if(data[i].children){
                this.indexBranch(data[i].children, parents.concat(data[i]));
            }
        }
    },

	getSearchIndexKeys:function () {
		if (this.index !== undefined) {
			return this.index;
		}
		var reservedKeys = ['children','searchIndex', 'uid'];

		var data = this.getDataFromSource();
		if (data.length > 0) {
			var record = Object.clone(data[0]);
			var ret = [];
			for (var key in record) {
				if (record.hasOwnProperty(key)) {
					if(reservedKeys.indexOf(key) === -1)ret.push(key);
				}
			}
			return ret;
		}
		return ['NA'];
	},

	/**
	 * Returns number of records in search result
	 * @function getCount
	 * @return {Number}
	 * @memberof ludo.dataSource.JSONArraySearch.prototype
	 */
	getCount:function () {
		return this.searchResult ? this.searchResult.length : 0;
	},

    // TODO fix this method
	searchToString:function () {
		return this.hasData() ? '' : '';
	}
});