/*
 *	jquery.suggest 1.1 - 2007-08-06
 *	
 *	Uses code and techniques from following libraries:
 *	1. http://www.dyve.net/jquery/?autocomplete
 *	2. http://dev.jquery.com/browser/trunk/plugins/interface/iautocompleter.js	
 *
 *	All the new stuff written by Peter Vulgaris (www.vulgarisoip.com)	
 *	Feel free to do whatever you want with this file
 *
 */

(function($) {

	$.suggest = function(input, options) {

		var $input = $(input).attr("autocomplete", "off");
		var $results = $(document.createElement("ul"));

		var timeout = false;		// hold timeout ID for suggestion results to appear	
		var prevLength = 0;			// last recorded length of $input.val()
		var cache = [];				// cache MRU list
		var cacheSize = 0;			// size of cache in chars (bytes?)
		
		$results.addClass(options.resultsClass).appendTo('body');
			

		resetPosition();
		$(window)
			.load(resetPosition)		// just in case user is changing size of page while loading
			.resize(resetPosition);

		$input.blur(function() {
			setTimeout(function() { $results.hide() }, 200);
		});
		
		
		// help IE users if possible
		try {
			$results.bgiframe();
		} catch(e) { }


		// I really hate browser detection, but I don't see any other way
		if ($.browser.mozilla)
			$input.keypress(processKey);	// onkeypress repeats arrow keys in Mozilla/Opera
		else
			$input.keydown(processKey);		// onkeydown repeats arrow keys in IE/Safari
		



		function resetPosition() {
			// requires jquery.dimension plugin
			var offset = $input.offset();
			$results.css({
				top: (offset.top + input.offsetHeight) + 'px',
				left: offset.left + 'px'
			});
		}
		
		
		function processKey(e) {
			
			// handling up/down/escape requires results to be visible
			// handling enter/tab requires that AND a result to be selected
			if ((/27$|38$|40$/.test(e.keyCode) && $results.is(':visible')) ||
				(/^13$|^9$/.test(e.keyCode) && getCurrentResult())) {
				
				if (e.preventDefault)
					e.preventDefault();
				if (e.stopPropagation)
					e.stopPropagation();

				e.cancelBubble = true;
				e.returnValue = false;
			
				switch(e.keyCode) {

					case 38: // up
						prevResult();
						break;
			
					case 40: // down
						nextResult();
						break;

					case 9:  // tab
					case 13: // return
						selectCurrentResult();
						break;
						
					case 27: //	escape
						$results.hide();
						break;

				}
				
			} else if ($input.val().length != prevLength) {

				if (timeout) 
					clearTimeout(timeout);
				timeout = setTimeout(suggest, options.delay);
				prevLength = $input.val().length;
				
			}			
				
			
		}
		
		
		function suggest() {
		
			var q = $.trim($input.val());

			if (q.length >= options.minchars) {
				
				cached = checkCache(q);
				
				if (cached) {
				
					displayItems(cached['items']);
					
				} else {
				
					$.get(options.source, {q: q}, function(txt) {

						$results.hide();
						
						var items = parseTxt(txt, q);
						
						displayItems(items);
						addToCache(q, items, txt.length);
						
					});
					
				}
				
			} else {
			
				$results.hide();
				
			}
				
		}
		
		
		function checkCache(q) {

			for (var i = 0; i < cache.length; i++)
				if (cache[i]['q'] == q) {
					cache.unshift(cache.splice(i, 1)[0]);
					return cache[0];
				}
			
			return false;
		
		}
		
		function addToCache(q, items, size) {

			while (cache.length && (cacheSize + size > options.maxCacheSize)) {
				var cached = cache.pop();
				cacheSize -= cached['size'];
			}
			
			cache.push({
				q: q,
				size: size,
				items: items
				});
				
			cacheSize += size;
		
		}
		
		function displayItems(items) {
			
			if (!items)
				return;
				
			if (!items.length) {
				$results.hide();
				return;
			}

			resetPosition(); // when the form moves after the page has loaded

			var html = '';
			for (var i = 0; i < items.length; i++)
				html += '<li>' + items[i] + '</li>';

			$results.html(html).show();
			
			$results
				.children('li')
				.mouseover(function() {
					$results.children('li').removeClass(options.selectClass);
					$(this).addClass(options.selectClass);
				})
				.click(function(e) {
					e.preventDefault(); 
					e.stopPropagation();
					selectCurrentResult();
				});
						
		}
		
		function parseTxt(txt, q) {
			
			var items = [];
			var tokens = txt.split(options.delimiter);
			
			// parse returned data for non-empty items
			for (var i = 0; i < tokens.length; i++) {
				var token = $.trim(tokens[i]);
				if (token) {
					token = token.replace(
						new RegExp(q, 'ig'), 
						function(q) { return '<span class="' + options.matchClass + '">' + q + '</span>' }
						);
					items[items.length] = token;
				}
			}
			
			return items;
		}
		
		function getCurrentResult() {
		
			if (!$results.is(':visible'))
				return false;
		
			var $currentResult = $results.children('li.' + options.selectClass);
			
			if (!$currentResult.length)
				$currentResult = false;
				
			return $currentResult;

		}
		
		function selectCurrentResult() {
		
			$currentResult = getCurrentResult();
		
			if ($currentResult) {
				$input.val($currentResult.text());
				$results.hide();
				
				if (options.onSelect)
					options.onSelect.apply($input[0]);
					
			}
		
		}
		
		function nextResult() {
		
			$currentResult = getCurrentResult();
		
			if ($currentResult)
				$currentResult
					.removeClass(options.selectClass)
					.next()
						.addClass(options.selectClass);
			else
				$results.children('li:first-child').addClass(options.selectClass);
		
		}
		
		function prevResult() {
		
			$currentResult = getCurrentResult();
		
			if ($currentResult)
				$currentResult
					.removeClass(options.selectClass)
					.prev()
						.addClass(options.selectClass);
			else
				$results.children('li:last-child').addClass(options.selectClass);
		
		}

	}
	
	$.fn.suggest = function(source, options) {
	
		if (!source)
			return;
	
		options = options || {};
		options.source = source;
		options.delay = options.delay || 100;
		options.resultsClass = options.resultsClass || 'ac_results';
		options.selectClass = options.selectClass || 'ac_over';
		options.matchClass = options.matchClass || 'ac_match';
		options.minchars = options.minchars || 2;
		options.delimiter = options.delimiter || '\n';
		options.onSelect = options.onSelect || false;
		options.maxCacheSize = options.maxCacheSize || 65536;

		this.each(function() {
			new $.suggest(this, options);
		});

		return this;
		
	};
	
})(jQuery);