Scholar.Search = function(){
	this._sql = null;
	this._sqlParams = null;
	this._maxSearchConditionID = 0;
	this._conditions = [];
	this._savedSearchID = null;
	this._savedSearchName = null;
}


/*
 * Set the name for the saved search
 *
 * Must be called before save() for new searches
 */
Scholar.Search.prototype.setName = function(name){
	if (!name){
		throw("Invalid saved search name '" + name + '"');
	}
	
	this._savedSearchName = name;
}


/*
 * Load a saved search from the DB
 */
Scholar.Search.prototype.load = function(savedSearchID){
	var sql = "SELECT savedSearchName, MAX(searchConditionID) AS maxID "
		+ "FROM savedSearches LEFT JOIN savedSearchConditions "
		+ "USING (savedSearchID) WHERE savedSearchID=" + savedSearchID
		+ " GROUP BY savedSearchID";
	var row = Scholar.DB.rowQuery(sql);
	
	if (!row){
		throw('Saved search ' + savedSearchID + ' does not exist');
	}
	
	this._sql = null;
	this._sqlParams = null;
	this._maxSearchConditionID = row['maxID'];
	this._conditions = [];
	this._savedSearchID = savedSearchID;
	this._savedSearchName = row['savedSearchName'];
	
	var conditions = Scholar.DB.query("SELECT * FROM savedSearchConditions "
		+ "WHERE savedSearchID=" + savedSearchID + " ORDER BY searchConditionID");
	
	for (var i in conditions){
		// Parse "condition[/mode]"
		var [condition, mode] =
			Scholar.SearchConditions.parseCondition(conditions[i]['condition']);
		
		if (!Scholar.SearchConditions.get(condition)){
			Scholar.debug("Invalid saved search condition '"
				+ condition + "' -- skipping", 2);
			continue;
		}
		
		this._conditions[conditions[i]['searchConditionID']] = {
			id: conditions[i]['searchConditionID'],
			condition: condition,
			mode: mode,
			operator: conditions[i]['operator'],
			value: conditions[i]['value'],
			required: conditions[i]['required']
		};
	}
}


Scholar.Search.prototype.getID = function(){
	return this._savedSearchID;
}


Scholar.Search.prototype.getName = function(){
	return this._savedSearchName;
}


/*
 * Save the search to the DB and return a savedSearchID
 *
 * For new searches, setName() must be called before saving
 */
Scholar.Search.prototype.save = function(){
	if (!this._savedSearchName){
		throw('Name not provided for saved search');
	}
	
	Scholar.DB.beginTransaction();
	
	if (this._savedSearchID){
		var sql = "UPDATE savedSearches SET savedSearchName=? WHERE savedSearchID=?";
		Scholar.DB.query(sql, [this._savedSearchName, this._savedSearchID]);
		
		Scholar.DB.query("DELETE FROM savedSearchConditions "
			+ "WHERE savedSearchID=" + this._savedSearchID);
	}
	else {
		var isNew = true;
		
		this._savedSearchID
			= Scholar.getRandomID('savedSearches', 'savedSearchID');
		
		var sql = "INSERT INTO savedSearches (savedSearchID, savedSearchName) "
			+ "VALUES (?,?)";
		Scholar.DB.query(sql,
			[this._savedSearchID, {string: this._savedSearchName}]);
	}
	
	// TODO: use proper bound parameters once DB class is updated
	for (var i in this._conditions){
		var sql = "INSERT INTO savedSearchConditions (savedSearchID, "
			+ "searchConditionID, condition, operator, value, required) "
			+ "VALUES (?,?,?,?,?,?)";
		
		// Convert condition and mode to "condition[/mode]"
		var condition = this._conditions[i]['mode'] ?
			this._conditions[i]['condition'] + '/' + this._conditions[i]['mode'] :
			this._conditions[i]['condition']
		
		var sqlParams = [
			this._savedSearchID, i, condition,
			this._conditions[i]['operator']
				? this._conditions[i]['operator'] : null,
			this._conditions[i]['value']
				? this._conditions[i]['value'] : null,
			this._conditions[i]['required']
				? 1 : null
		];
		Scholar.DB.query(sql, sqlParams);
	}
	
	Scholar.DB.commitTransaction();
	Scholar.Notifier.trigger(
		(isNew ? 'add' : 'modify'), 'search', this._savedSearchID
	);
	return this._savedSearchID;
}


Scholar.Search.prototype.addCondition = function(condition, operator, value, required){
	if (!Scholar.SearchConditions.hasOperator(condition, operator)){
		throw ("Invalid operator '" + operator + "' for condition " + condition);
	}
	
	// Shortcut to add a condition on every table -- does not return an id
	if (condition=='quicksearch'){
		this.addCondition('joinMode', 'any');
		
		// Quicksearch words don't need to be phrases
		var words = Scholar.Fulltext.semanticSplitter(value);
		for each(var i in words){
			this.addCondition('blockStart');
			this.addCondition('title', operator, i, false);
			this.addCondition('field', operator, i, false);
			this.addCondition('numberfield', operator, i, false);
			this.addCondition('creator', operator, i, false);
			this.addCondition('tag', operator, i, false);
			this.addCondition('note', operator, i, false);
			this.addCondition('fulltextWord', operator, i, false);
			this.addCondition('blockEnd');
		}
		return false;
	}
	
	var searchConditionID = ++this._maxSearchConditionID;
	
	var [condition, mode] = Scholar.SearchConditions.parseCondition(condition);
	
	this._conditions[searchConditionID] = {
		id: searchConditionID,
		condition: condition,
		mode: mode,
		operator: operator,
		value: value,
		required: required
	};
	
	this._sql = null;
	this._sqlParams = null;
	return searchConditionID;
}


Scholar.Search.prototype.updateCondition = function(searchConditionID, condition, operator, value, required){
	if (typeof this._conditions[searchConditionID] == 'undefined'){
		throw ('Invalid searchConditionID ' + searchConditionID + ' in updateCondition()');
	}
	
	if (!Scholar.SearchConditions.hasOperator(condition, operator)){
		throw ("Invalid operator '" + operator + "' for condition " + condition);
	}
	
	this._conditions[searchConditionID] = {
		id: searchConditionID,
		condition: condition,
		operator: operator,
		value: value,
		required: required
	};
	
	this._sql = null;
	this._sqlParams = null;
}


Scholar.Search.prototype.removeCondition = function(searchConditionID){
	if (typeof this._conditions[searchConditionID] == 'undefined'){
		throw ('Invalid searchConditionID ' + searchConditionID + ' in removeCondition()');
	}
	
	delete this._conditions[searchConditionID];
}


/*
 * Returns an array with 'condition', 'operator', 'value', 'required'
 * for the given searchConditionID
 */
Scholar.Search.prototype.getSearchCondition = function(searchConditionID){
	return this._conditions[searchConditionID];
}


/*
 * Returns a multidimensional array of conditions/operator/value sets
 * used in the search, indexed by searchConditionID
 */
Scholar.Search.prototype.getSearchConditions = function(){
	// TODO: make copy
	return this._conditions;
}


/*
 * Run the search and return an array of item ids for results
 */
Scholar.Search.prototype.search = function(){
	if (!this._sql){
		this._buildQuery();
	}
	
	var ids = Scholar.DB.columnQuery(this._sql, this._sqlParams);
	
	if (!ids){
		return false;
	}
	
	// Filter results with fulltext search
	for each(var condition in this._conditions){
		if (condition['condition']=='fulltextContent'){
			var fulltextIDs = Scholar.Fulltext.findTextInItems(ids,
				condition['value'],	condition['mode']);
			
			var hash = {};
			for each(var val in fulltextIDs){
				hash[val.id] = true;
			}
			
			switch (condition['operator']){
				case 'contains':
					var filter = function(val,  index, array){
						return hash[val] ? true : false;
					}
					break;
				
				case 'doesNotContain':
					var filter = function(val,  index, array){
						return hash[val] ? false : true;
					}
					break;
					
				default:
					continue;
			}
			
			var ids = ids.filter(filter);
		}
	}
	
	return ids;
}


/*
 * Get the SQL string for the search
 */
Scholar.Search.prototype.getSQL = function(){
	if (!this._sql){
		this._buildQuery();
	}
	return this._sql;
}


Scholar.Search.prototype.getSQLParams = function(){
	if (!this._sql){
		this._buildQuery();
	}
	return this._sqlParams;
}


/*
 * Build the SQL query for the search
 */
Scholar.Search.prototype._buildQuery = function(){
	var sql = 'SELECT itemID FROM items';
	var sqlParams = [];
	// Separate ANY conditions for 'required' condition support
	var anySQL = '';
	var anySQLParams = [];
	
	var conditions = [];
	
	for (var i in this._conditions){
		var data = Scholar.SearchConditions.get(this._conditions[i]['condition']);
		
		if (data['table']){
			conditions.push({
				name: data['name'],
				alias: data['name']!=this._conditions[i]['condition']
					? this._conditions[i]['condition'] : false,
				table: data['table'],
				field: data['field'],
				operator: this._conditions[i]['operator'],
				value: this._conditions[i]['value'],
				required: this._conditions[i]['required']
			});
			
			var hasConditions = true;
		}
		
		// Handle special conditions
		else {
			switch (data['name']){
				// Search subfolders
				case 'recursive':
					var recursive = this._conditions[i]['operator']=='true';
					continue;
					
				// Join mode ('any' or 'all')
				case 'joinMode':
					var joinMode = this._conditions[i]['operator'].toUpperCase();
					continue;
				
				case 'fulltextContent':
					// Handled in Search.search()
					continue;
				
				// For quicksearch block markers
				case 'blockStart':
					conditions.push({name:'blockStart'});
					continue;
				case 'blockEnd':
					conditions.push({name:'blockEnd'});
					continue;
			}
			
			throw ('Unhandled special condition ' + this._conditions[i]['condition']);
		}
	}
	
	if (hasConditions){
		sql += " WHERE ";
		
		for each(var condition in conditions){
				var openParens = 0;
				var skipOperators = false;
				var condSQL = '';
				var condSQLParams = [];
				
				//
				// Special table handling
				//
				if (condition['table']){
					switch (condition['table']){
						case 'savedSearches':
							break;
						default:
							condSQL += 'itemID '
							switch (condition['operator']){
								case 'isNot':
								case 'doesNotContain':
									condSQL += 'NOT ';
									break;
							}
							condSQL += 'IN (SELECT itemID FROM ' +
								condition['table'] + ' WHERE (';
							openParens = 2;
					}
				}
				
				//
				// Special condition handling
				//
				switch (condition['name']){
					case 'field':
					case 'datefield':
						if (!condition['alias']){
							break;
						}
						condSQL += 'fieldID=? AND ';
						condSQLParams.push(
							Scholar.ItemFields.getID(condition['alias'])
						);
						break;
					
					case 'collectionID':
						condSQL += "collectionID IN (?,";
						condSQLParams.push({int:condition['value']});
						
						// And descendents if recursive search
						if (recursive){
							var col = Scholar.Collections.get(condition['value']);
							var descendents = col.getDescendents(false, 'collection');
							if (descendents){
								for (var k in descendents){
									condSQL += '?,';
									condSQLParams.push(descendents[k]['id']);
								}
							}
						}
						
						// Strip final comma
						condSQL = condSQL.substring(0, condSQL.length-1) + ")";
						
						skipOperators = true;
						break;
					
					case 'savedSearchID':
						condSQL += "itemID ";
						if (condition['operator']=='isNot'){
							condSQL += "NOT ";
						}
						condSQL += "IN (";
						var search = new Scholar.Search();
						search.load(condition['value']);
						
						// Check if there are any post-search filters
						var subconds = search.getSearchConditions();
						var hasFilter;
						for each(var k in subconds){
							if (k.condition == 'fulltextContent'){
								hasFilter = true;
								break;
							}
						}
						// This is an ugly and inefficient way of doing a
						// subsearch, but it's necessary if there are any
						// post-search filters (e.g. fulltext scanning)
						if (hasFilter){
							var subids = search.search();
							condSQL += subids.join();
						}
						// Otherwise just put the SQL in a subquery
						else {
							condSQL += search.getSQL();
							var subpar = search.getSQLParams();
							for (var k in subpar){
								condSQLParams.push(subpar[k]);
							}
						}
						condSQL += ")";
						
						skipOperators = true;
						break;
					
					case 'tag':
						condSQL += "tagID IN (SELECT tagID FROM tags WHERE ";
						openParens++;
						break;
					
					case 'creator':
						condSQL += "creatorID IN (SELECT creatorID FROM creators "
							+ "WHERE ";
						openParens++;
						break;
					
					case 'fulltextWord':
						condSQL += "wordID IN (SELECT wordID FROM fulltextWords "
							+ "WHERE ";
						openParens++;
						break;
					
					// For quicksearch blocks
					case 'blockStart':
					case 'blockEnd':
						skipOperators = true;
						break;
				}
				
				if (!skipOperators){
					condSQL += condition['field'];
					switch (condition['operator']){
						case 'contains':
						case 'doesNotContain': // excluded with NOT IN above
							condSQL += ' LIKE ?';
							condSQLParams.push('%' + condition['value'] + '%');
							break;
							
						case 'is':
						case 'isNot': // excluded with NOT IN above
							condSQL += '=?';
							condSQLParams.push(condition['value']);
							break;
						
						/*
						case 'beginsWith':
							condSQL += '=?';
							condSQLParams.push(condition['value'] + '%');
							break;
						*/
						
						case 'isLessThan':
							condSQL += '<?';
							condSQLParams.push({int:condition['value']});
							break;
							
						case 'isGreaterThan':
							condSQL += '>?';
							condSQLParams.push({int:condition['value']});
							break;
							
						case 'isBefore':
							condSQL += '<?';
							condSQLParams.push({string:condition['value']});
							break;
							
						case 'isAfter':
							condSQL += '>?';
							condSQLParams.push({string:condition['value']});
							break;
					}
				}
				
				// Close open parentheses
				for (var k=openParens; k>0; k--){
					condSQL += ')';
				}
				
				// Keep non-required conditions separate if in ANY mode
				if (!condition['required'] && joinMode=='ANY'){
					// Little hack to allow multiple quicksearch words
					if (condition['name'] == 'blockStart'){
						condSQL += '(';
					}
					else if (condition['name'] == 'blockEnd'){
						// Strip ' OR ' from last condition
						anySQL = anySQL.substring(0, anySQL.length-4);
						condSQL += ') AND ';
					}
					else {
						condSQL += ' OR ';
					}
					anySQL += condSQL;
					anySQLParams = anySQLParams.concat(condSQLParams);
				}
				else {
					condSQL += ' AND ';
					sql += condSQL;
					sqlParams = sqlParams.concat(condSQLParams);
				}
		}
		
		// Add on ANY conditions
		if (anySQL){
			sql += '(' + anySQL;
			sqlParams = sqlParams.concat(anySQLParams);
			// If we ended with a block, remove ' AND ', otherwise ' OR '
			var remlen = condition['name']=='blockEnd' ? 5 : 4;
			sql = sql.substring(0, sql.length-remlen);
			sql += ')';
		}
		else {
			sql = sql.substring(0, sql.length-5); // remove last ' AND '
		}
	}
	
	this._sql = sql;
	this._sqlParams = sqlParams.length ? sqlParams : null;
}


Scholar.Searches = new function(){
	this.get = get;
	this.getAll = getAll;
	this.erase = erase;
	
	
	function get(id){
		var sql = "SELECT savedSearchID AS id, savedSearchName AS name "
			+ "FROM savedSearches WHERE savedSearchID=?";
		return Scholar.DB.rowQuery(sql, [id]);
	}
	
	
	/*
	 * Returns an array of saved searches with 'id' and 'name', ordered by name
	 */
	function getAll(){
		var sql = "SELECT savedSearchID AS id, savedSearchName AS name "
			+ "FROM savedSearches ORDER BY name";
		return Scholar.DB.query(sql);
	}
	
	
	/*
	 * Delete a given saved search from the DB
	 */
	function erase(savedSearchID){
		Scholar.DB.beginTransaction();
		var sql = "DELETE FROM savedSearchConditions WHERE savedSearchID="
			+ savedSearchID;
		Scholar.DB.query(sql);
		
		var sql = "DELETE FROM savedSearches WHERE savedSearchID="
			+ savedSearchID;
		Scholar.DB.query(sql);
		Scholar.DB.commitTransaction();
		
		Scholar.Notifier.trigger('remove', 'search', savedSearchID);
	}
}


Scholar.SearchConditions = new function(){
	this.get = get;
	this.getStandardConditions = getStandardConditions;
	this.hasOperator = hasOperator;
	this.parseCondition = parseCondition;
	
	var _initialized = false;
	var _conditions = [];
	var _standardConditions = [];
	
	/*
	 * Define the advanced search operators
	 */
	var _operators = {
		// Standard -- these need to match those in scholarsearch.xml
		is: true,
		isNot: true,
		contains: true,
		doesNotContain: true,
		isLessThan: true,
		isGreaterThan: true,
		isBefore: true,
		isAfter: true,
		
		// Special
		any: true,
		all: true,
		true: true,
		false: true
	};
	
	
	/*
	 * Define and set up the available advanced search conditions
	 */
	function _init(){
		_conditions = [
			//
			// Special conditions
			//
			
			// Search recursively
			{
				name: 'recursive',
				operators: {
					true: true,
					false: true
				}
			},
			
			// Join mode
			{
				name: 'joinMode',
				operators: {
					any: true,
					all: true
				}
			},
			
			// Saved search to search within
			{
				name: 'savedSearchID',
				operators: {
					is: true,
					isNot: true
				},
				table: 'savedSearches',
				field: 'savedSearchID',
				special: true
			},
			
			{
				name: 'quicksearch',
				operators: {
					is: true,
					isNot: true,
					contains: true,
					doesNotContain: true
				}
			},
			
			// Quicksearch block markers
			{
				name: 'blockStart'
			},
			
			{
				name: 'blockEnd'
			},
			
			//
			// Standard conditions
			//
			
			// Collection id to search within
			{
				name: 'collectionID',
				operators: {
					is: true,
					isNot: true
				},
				table: 'collectionItems',
				field: 'collectionID'
			},
			
			{
				name: 'title',
				operators: {
					contains: true,
					doesNotContain: true
				},
				table: 'items',
				field: 'title'
			},
			
			{
				name: 'dateAdded',
				operators: {
					is: true,
					isNot: true,
					isBefore: true,
					isAfter: true
				},
				table: 'items',
				field: 'DATE(dateAdded)'
			},
			
			{
				name: 'dateModified',
				operators: {
					is: true,
					isNot: true,
					isBefore: true,
					isAfter: true
				},
				table: 'items',
				field: 'DATE(dateModified)'
			},
			
			{
				name: 'itemTypeID',
				operators: {
					is: true,
					isNot: true
				},
				table: 'items',
				field: 'itemTypeID'
			},
			
			{
				name: 'tagID',
				operators: {
					is: true,
					isNot: true
				},
				table: 'itemTags',
				field: 'tagID',
				special: true
			},
			
			{
				name: 'tag',
				operators: {
					is: true,
					isNot: true,
					contains: true,
					doesNotContain: true
				},
				table: 'itemTags',
				field: 'tag'
			},
			
			{
				name: 'note',
				operators: {
					contains: true,
					doesNotContain: true
				},
				table: 'itemNotes',
				field: 'note'
			},
			
			{
				name: 'creator',
				operators: {
					is: true,
					isNot: true,
					contains: true,
					doesNotContain: true
				},
				table: 'itemCreators',
				field: "firstName || ' ' || lastName"
			},
			
			{
				name: 'field',
				operators: {
					is: true,
					isNot: true,
					contains: true,
					doesNotContain: true
				},
				table: 'itemData',
				field: 'value',
				aliases: Scholar.DB.columnQuery("SELECT fieldName FROM fields " +
					"WHERE fieldName NOT IN ('accessDate', 'date', 'pages', " +
					"'section','accessionNumber','seriesNumber','issue')"),
				template: true // mark for special handling
			},
			
			{
				name: 'datefield',
				operators: {
					is: true,
					isNot: true,
					isBefore: true,
					isAfter: true
				},
				table: 'itemData',
				field: 'DATE(value)',
				aliases: ['accessDate', 'date'],
				template: true // mark for special handling
			},
			
			{
				name: 'numberfield',
				operators: {
					is: true,
					isNot: true,
					contains: true,
					doesNotContain: true,
					isLessThan: true,
					isGreaterThan: true
				},
				table: 'itemData',
				field: 'value',
				aliases: ['pages', 'section', 'accessionNumber',
					'seriesNumber','issue'],
				template: true // mark for special handling
			},
			
			{
				name: 'fulltextWord',
				operators: {
					contains: true,
					doesNotContain: true
				},
				table: 'fulltextItems',
				field: 'word',
				special: true
			},
			
			
			{
				name: 'fulltextContent',
				operators: {
					contains: true,
					doesNotContain: true
				},
				special: false
			}

		];
		
		// Index conditions by name and aliases
		for (var i in _conditions){
			_conditions[_conditions[i]['name']] = _conditions[i];
			if (_conditions[i]['aliases']){
				for (var j in _conditions[i]['aliases']){
					_conditions[_conditions[i]['aliases'][j]] = _conditions[i];
				}
			}
			_conditions[_conditions[i]['name']] = _conditions[i];
			delete _conditions[i];
		}
		
		var sortKeys = [];
		var sortValues = [];
		
		// Separate standard conditions for menu display
		for (var i in _conditions){
			// If explicitly special or a template master (e.g. 'field') or
			// no table and not explicitly unspecial, skip
			if (_conditions[i]['special'] ||
				(_conditions[i]['template'] && i==_conditions[i]['name']) ||
				(!_conditions[i]['table'] &&
					typeof _conditions[i]['special'] == 'undefined')){
				continue;
			}
			
			try {
				var localized = Scholar.getString('searchConditions.' + i)
			}
			catch (e){
				var localized = Scholar.getString('itemFields.' + i);
			}
			
			sortKeys.push(localized);
			sortValues[localized] = {
				name: i,
				localized: localized,
				operators: _conditions[i]['operators']
			};
		}
		
		// Alphabetize by localized name
		sortKeys = sortKeys.sort();
		for each(var i in sortKeys){
			_standardConditions.push(sortValues[i]);
		}
		
		_initialized = true;
	}
	
	
	/*
	 * Get condition data
	 */
	function get(condition){
		if (!_initialized){
			_init();
		}
		
		return _conditions[condition];
	}
	
	
	/*
	 * Returns array of possible conditions
	 *
	 * Does not include special conditions, only ones that would show in a drop-down list
	 */
	function getStandardConditions(){
		if (!_initialized){
			_init();
		}
		
		// TODO: return copy instead
		return _standardConditions;
	}
	
	
	/*
	 * Check if an operator is valid for a given condition
	 */
	function hasOperator(condition, operator){
		if (!_initialized){
			_init();
		}
		
		var [condition, mode] = this.parseCondition(condition);
		
		if (!_conditions[condition]){
			throw ("Invalid condition '" + condition + "' in hasOperator()");
		}
		
		if (!operator && typeof _conditions[condition]['operators'] == 'undefined'){
			return true;
		}
		
		return !!_conditions[condition]['operators'][operator];
	}
	
	
	function parseCondition(condition){
		var mode = false;
		var pos = condition.indexOf('/');
		if (pos != -1){
			mode = condition.substr(pos+1);
			condition = condition.substr(0, pos);
		}
		
		return [condition, mode];
	}
}