/*
 * jQuery autocomplete plugin
 * Version 2.0.0  (2008-03-22)
 * @requires jQuery v1.1.1+
 *
 * Dual licensed under the MIT and GPL licenses:
 * http://www.opensource.org/licenses/mit-license.php
 * http://www.gnu.org/licenses/gpl.html
 *
 * Dylan Verheul
 * http://www.dyve.net/jquery
 *
 */
(function($) {
	/**
	 * The autocompleter object
	 */
	$.autocomplete = function(input, options) {

		// Create a link to self
		var me = this;
		// Create jQuery object for input element
		var $input = $(input).attr("autocomplete", "off");
		// Apply inputClass if necessary
		if (options.inputClass) {
			$input.addClass(options.inputClass);
		}

		// Create results
		var results = document.createElement("div");

		// Create jQuery object for results
		// var $results = $(results);
		var $results = $(results).hide().addClass(options.resultsClass).css("position", "absolute");
		if( options.width > 0 ) {
			$results.css("width", options.width);
		}

		// Add to body element
		$("body").append(results);

		input.autocompleter = me;

		var timeout = null;
		var prev = "";
		var active = -1;
		var cache = {};
		var keyb = false;
		var hasFocus = false;
		var lastKeyPressCode = null;
		var mouseDownOnSelect = false;
		var hidingResults = false;

		// flush cache
		function flushCache(){
			cache = {};
			cache.data = {};
			cache.length = 0;
		};

		// flush cache
		flushCache();

		// if there is a data array supplied
		if( options.data != null ){
			var sFirstChar = "", stMatchSets = {}, row = [];

			// no url was specified, we need to adjust the cache length to make sure it fits the local data store
			if (typeof options.url != "string") {
				options.cacheLength = 1;
			}

			// loop through the array and create a lookup structure
			for( var i=0; i < options.data.length; i++ ){
				// if row is a string, make an array otherwise just reference the array
				row = ((typeof options.data[i] == "string") ? [options.data[i]] : options.data[i]);

				// if the length is zero, don't add to list
				if( row[0].length > 0 ){
					// get the first character
					sFirstChar = row[0].substring(0, 1).toLowerCase();
					// if no lookup array for this character exists, look it up now
					if( !stMatchSets[sFirstChar] ) stMatchSets[sFirstChar] = [];
					// if the match is a string
					stMatchSets[sFirstChar].push(row);
				}
			}

			// add the data items to the cache
			for (var k in stMatchSets) {
				// increase the cache size
				options.cacheLength++;
				// add to the cache
				addToCache(k, stMatchSets[k]);
			}
		}

		$input
		.keydown(function(e) {
			// track last key pressed
			lastKeyPressCode = e.keyCode;
			switch(e.keyCode) {
				case 38: // up
					e.preventDefault();
					moveSelect(-1);
					break;
				case 40: // down
					e.preventDefault();
					moveSelect(1);
					break;
				case 9:  // tab
				case 13: // return
					if( selectCurrent() ){
						// make sure to blur off the current field
						$input.blur();
						e.preventDefault();
						// give focus with a small timeout (weird behaviour in FF)
						setTimeout(function() { $input.focus() }, 10);
					}
					break;
				default:
					active = -1;
					if (timeout) clearTimeout(timeout);
					timeout = setTimeout(onChange, options.delay);
					break;
			}
		})
		.focus(function(){
			// track whether the field has focus, we shouldn't process any results if the field no longer has focus
			hasFocus = true;
		})
		.blur(function() {
			// track whether the field has focus
			hasFocus = false;
			if (!mouseDownOnSelect) {
				hideResults();
			}
		});

		hideResultsNow();

		function onChange() {
			// ignore if the following keys are pressed: [del] [shift] [capslock]
			if( lastKeyPressCode == 46 || (lastKeyPressCode > 8 && lastKeyPressCode < 32) ) return $results.hide();
			var v = $input.val();
			if (v == prev) return;
			prev = v;
			if (v.length >= options.minChars) {
				$input.addClass(options.loadingClass);
				requestData(v);
			} else {
				$input.removeClass(options.loadingClass);
				$results.hide();
			}
		};

	 	function moveSelect(step) {

			var lis = $("li", results);
			if (!lis) return;

			active += step;

			if (active < 0) {
				active = 0;
			} else if (active >= lis.size()) {
				active = lis.size() - 1;
			}

			lis.removeClass("ac_over");

			$(lis[active]).addClass("ac_over");

			// Weird behaviour in IE
			// if (lis[active] && lis[active].scrollIntoView) {
			// 	lis[active].scrollIntoView(false);
			// }

		};

		function selectCurrent() {
			var li = $("li.ac_over", results)[0];
			if (!li) {
				var $li = $("li", results);
				if (options.selectOnly) {
					if ($li.length == 1) li = $li[0];
				} else if (options.selectFirst) {
					li = $li[0];
				}
			}
			if (li) {
				selectItem(li);
				return true;
			} else {
				return false;
			}
		};

		function selectItem(li) {
			if (!li) {
				li = document.createElement("li");
				li.extra = [];
				li.selectValue = "";
			}
			var v = $.trim(li.selectValue ? li.selectValue : li.innerHTML);
			input.lastSelected = v;
			prev = v;
			$results.html("");
			$input.val(v);
			hideResultsNow();
			if (options.onItemSelect) {
				setTimeout(function() { options.onItemSelect(li) }, 1);
			}
		};

		// selects a portion of the input string
		function createSelection(start, end){
			// get a reference to the input element
			var field = $input.get(0);
			if( field.createTextRange ){
				var selRange = field.createTextRange();
				selRange.collapse(true);
				selRange.moveStart("character", start);
				selRange.moveEnd("character", end);
				selRange.select();
			} else if( field.setSelectionRange ){
				field.setSelectionRange(start, end);
			} else {
				if( field.selectionStart ){
					field.selectionStart = start;
					field.selectionEnd = end;
				}
			}
			field.focus();
		};

		// fills in the input box w/the first match (assumed to be the best match)
		function autoFill(sValue){
			// if the last user key pressed was backspace, don't autofill
			if( lastKeyPressCode != 8 ){
				// fill in the value (keep the case the user has typed)
				$input.val($input.val() + sValue.substring(prev.length));
				// select the portion of the value not typed by the user (so the next character will erase)
				createSelection(prev.length, sValue.length);
			}
		};

		function showResults() {
			// get the position of the input field right now (in case the DOM is shifted)
			var pos = findPos(input);
			// either use the specified width, or autocalculate based on form element
			var iWidth = (options.width > 0) ? options.width : $input.width();
			// reposition
			$results.css({
				width: parseInt(iWidth) + "px",
				top: (pos.y + input.offsetHeight) + "px",
				left: pos.x + "px"
			}).show();
		};

		function hideResults() {
			if (timeout) clearTimeout(timeout);
			timeout = setTimeout(hideResultsNow, 200);
		};

		function hideResultsNow() {
			if (hidingResults) {
				return;
			}
			hidingResults = true;

			if (timeout) {
				clearTimeout(timeout);
			}

			var v = $input.removeClass(options.loadingClass).val();

			if ($results.is(":visible")) {
				$results.hide();
			}

			if (options.mustMatch) {
				if (!input.lastSelected || input.lastSelected != v) {
					selectItem(null);
				}
			}

			hidingResults = false;
		};

		function receiveData(q, data) {
			if (data) {
				$input.removeClass(options.loadingClass);
				results.innerHTML = "";

				// if the field no longer has focus or if there are no matches, do not display the drop down
				if( !hasFocus || data.length == 0 ) return hideResultsNow();

				if ($.browser.msie) {
					// we put a styled iframe behind the calendar so HTML SELECT elements don't show through
					$results.append(document.createElement('iframe'));
				}
				results.appendChild(dataToDom(data));
				// autofill in the complete box w/the first match as long as the user hasn't entered in more data
				if( options.autoFill && ($input.val().toLowerCase() == q.toLowerCase()) ) autoFill(data[0][0]);
				showResults();
			} else {
				hideResultsNow();
			}
		};

		function parseData(data) {
			if (!data) return null;
			var parsed = [];
			var rows = data.split(options.lineSeparator);
			for (var i=0; i < rows.length; i++) {
				var row = $.trim(rows[i]);
				if (row) {
					parsed[parsed.length] = row.split(options.cellSeparator);
				}
			}
			return parsed;
		};

		function dataToDom(data) {
			var ul = document.createElement("ul");
			var num = data.length;

			// limited results to a max number
			if( (options.maxItemsToShow > 0) && (options.maxItemsToShow < num) ) num = options.maxItemsToShow;

			for (var i=0; i < num; i++) {
				var row = data[i];
				if (!row) continue;
				var li = document.createElement("li");
				if (options.formatItem) {
					li.innerHTML = options.formatItem(row, i, num);
					li.selectValue = row[0];
				} else {
					li.innerHTML = row[0];
					li.selectValue = row[0];
				}
				var extra = null;
				if (row.length > 1) {
					extra = [];
					for (var j=1; j < row.length; j++) {
						extra[extra.length] = row[j];
					}
				}
				li.extra = extra;
				ul.appendChild(li);

				$(li).hover(
					function() {
						var $this = $(this);
					 	active = $("li", ul).removeClass("ac_over").index($this[0]);
					 	$this.addClass("ac_over");
					},
					function() {
						$(this).removeClass("ac_over");
					}
				).click(function(e) { 
					e.preventDefault();
					e.stopPropagation();
					selectItem(this)
				});

			}
			$(ul).mousedown(function() {
				mouseDownOnSelect = true;
			}).mouseup(function() {
				mouseDownOnSelect = false;
			});
			return ul;
		};

		function requestData(q) {
			if (!options.matchCase) q = q.toLowerCase();
			var data = options.cacheLength ? loadFromCache(q) : null;
			// recieve the cached data
			if (data) {
				receiveData(q, data);
			// if an AJAX url has been supplied, try loading the data now
			} else if( (typeof options.url == "string") && (options.url.length > 0) ){
				$.get(makeUrl(q), function(data) {
					data = parseData(data);
					addToCache(q, data);
					receiveData(q, data);
				});
			// if there's been no data found, remove the loading class
			} else {
				$input.removeClass(options.loadingClass);
			}
		};

		function makeUrl(q) {
			var sep = options.url.indexOf('?') == -1 ? '?' : '&'; 
			var url = options.url + sep + "q=" + encodeURI(q);
			for (var i in options.extraParams) {
				url += "&" + i + "=" + encodeURI(options.extraParams[i]);
			}
			return url;
		};

		function loadFromCache(q) {
			if (!q) return null;
			if (cache.data[q]) return cache.data[q];
			if (options.matchSubset) {
				for (var i = q.length - 1; i >= options.minChars; i--) {
					var qs = q.substr(0, i);
					var c = cache.data[qs];
					if (c) {
						var csub = [];
						for (var j = 0; j < c.length; j++) {
							var x = c[j];
							var x0 = x[0];
							if (matchSubset(x0, q)) {
								csub[csub.length] = x;
							}
						}
						return csub;
					}
				}
			}
			return null;
		};

		function matchSubset(s, sub) {
			if (!options.matchCase) s = s.toLowerCase();
			var i = s.indexOf(sub);
			if (i == -1) return false;
			return i == 0 || options.matchContains;
		};

		this.flushCache = function() {
			flushCache();
		};

		this.setExtraParams = function(p) {
			options.extraParams = p;
		};

		this.findValue = function(){
			var q = $input.val();

			if (!options.matchCase) q = q.toLowerCase();
			var data = options.cacheLength ? loadFromCache(q) : null;
			if (data) {
				findValueCallback(q, data);
			} else if( (typeof options.url == "string") && (options.url.length > 0) ){
				$.get(makeUrl(q), function(data) {
					data = parseData(data)
					addToCache(q, data);
					findValueCallback(q, data);
				});
			} else {
				// no matches
				findValueCallback(q, null);
			}
		}

		function findValueCallback(q, data){
			if (data) $input.removeClass(options.loadingClass);

			var num = (data) ? data.length : 0;
			var li = null;

			for (var i=0; i < num; i++) {
				var row = data[i];

				if( row[0].toLowerCase() == q.toLowerCase() ){
					li = document.createElement("li");
					if (options.formatItem) {
						li.innerHTML = options.formatItem(row, i, num);
						li.selectValue = row[0];
					} else {
						li.innerHTML = row[0];
						li.selectValue = row[0];
					}
					var extra = null;
					if( row.length > 1 ){
						extra = [];
						for (var j=1; j < row.length; j++) {
							extra[extra.length] = row[j];
						}
					}
					li.extra = extra;
				}
			}

			if( options.onFindValue ) setTimeout(function() { options.onFindValue(li) }, 1);
		}

		function addToCache(q, data) {
			if (!data || !q || !options.cacheLength) return;
			if (!cache.length || cache.length > options.cacheLength) {
				flushCache();
				cache.length++;
			} else if (!cache[q]) {
				cache.length++;
			}
			cache.data[q] = data;
		};

		function findPos(obj) {
			var curleft = obj.offsetLeft || 0;
			var curtop = obj.offsetTop || 0;
			while (obj = obj.offsetParent) {
				curleft += obj.offsetLeft
				curtop += obj.offsetTop
			}
			return {x:curleft,y:curtop};
		}
	}

	/**
	 * The autocomplete plugin itself
	 */
	$.fn.autocomplete = function(url, options, data) {

		// Make sure options exists
		options = options || {};
		// Set url as option
		options.url = url;
		// set some bulk local data
		options.data = ((typeof data == "object") && (data.constructor == Array)) ? data : null;

		// Set default values for required options (set global defaults in $.fn.autocomplete.defaults)
		options = $.extend({
			inputClass: "ac_input",
			resultsClass: "ac_results",
			lineSeparator: "\n",
			cellSeparator: "|",
			minChars: 1,
			delay: 400,
			matchCase: 0,
			matchSubset: 1,
			matchContains: 0,
			cacheLength: 1,
			mustMatch: 0,
			extraParams: {},
			loadingClass: "ac_loading",
			selectFirst: false,
			selectOnly: false,
			maxItemsToShow: -1,
			autoFill: false,
			width: 0
		}, $.fn.autocomplete.defaults, options);
	    
		options.width = parseInt(options.width, 10);
		
		return this.each(function() {
			var input = this;
			new $.autocomplete(input, options);
		});

	}

})(jQuery);