// global constants
var minSearchLength=2,  // min. number of characters to activate preview
	maxSearchCacheEntries=20; // number of cache entries

// global vars
var searchPreviewTimeout, searchCache, $searchForm, $liefInput, $searchInput;

// clears the timer
var clearTimer = function() {
	window.clearTimeout(searchPreviewTimeout);
	return true;
};

// returns a list element with events, cloning via $.clone(true) did not work
var getResultNode = function(str) {
	
	return $('<li>' + str + '</li>').bind('click.search', function(){
			// unbind click handler
			var $this = $(this).siblings().andSelf().unbind('click.search').end().end();

			// fill search field/submit form
			var idPrefix = $this.parent().attr('id').replace(/-result-list/,''),
				$input = $searchForm.find('#input-' + idPrefix),
				isLief = (idPrefix == 'lief');

			if (isLief) { // Lieferanten
				$input.val($this.html()).next('div.search-preview-container').hide();
				$searchInput.focus().select();
			}
			else { // Artikel/Katalog
				$input.val($this.data('qResult'));
				$searchForm.submit();
			}
			return false;
		}).hover(
			function(){
				$(this).addClass('over');
			},
			function(){
				$(this).removeClass('over');
			}
		);
};

// input field event handler
var addInputEventHandler = function($input, backendUrl, isLief, isKatalog) {
	var $preview = $input.siblings('div.search-preview-container'),
		$wait = $preview.find('div.wait-container'),
		$noResult = $preview.find('div.noresult'),
		$result = $noResult.next('div'),
		$resultList = $preview.find('ul.search-result-list'),
		$resultBtns = isLief
			? null
			: $result.find('a[id^=btn-search-result-]').bind('click.search',function() {
					// button up/down clicked?
					var args = $input.data('backendArgs');
					getPreviewList($input, backendUrl, isLief, isKatalog,
							args.value, $(this).data('limit'), args.Aufruf_art, args.SucheUeber);
				});

	//console.log('addInputEventHandler() isLief:', isLief, ', isKatalog:', isKatalog, ', input[name]=' + $input.attr('name'));

	// store data/jQuery elements, add event handler
	$input.data('$el',
			{'input':$input, 'preview':$preview, 'wait':$wait, 'noResult':$noResult,
			'result':$result, 'btns':$resultBtns, 'resultList':$resultList})
	.focus(function() { // hide other preview containers
		$searchForm.find('div.search-preview-container:visible').not($preview).hide();
	}).keyup(function(e){
		var key = TCode(e),
			value = $.trim($(this).val()),
			lastQuery = $input.data('lastquery') || '';
			children = null;

		// hide container
		$preview.children().andSelf().hide();

		if (lastQuery == value // backspace=8, tab=9, delete=46
			|| isLief && (value=='' || key==8 || key==9 || key==46)
			|| !isLief && value.length < minSearchLength){
			$preview.hide();
			return false;
		}
		if (!isLief && key== 13) { // submit form
			$searchForm.submit();
			return false;
		}
		$input.data('lastquery', value); // store last query

		// Lieferanten
		if (isLief) {
			$wait.show();
			getPreviewList($input, backendUrl, isLief, isKatalog, value);
			return false;
		}
		// Artikel, Katalog
		var $withPreview = $searchForm.find('input[name=ShowVorschau]');
		if ($withPreview.length == 1 && $withPreview.val() == "1") {
			clearTimer();
			searchPreviewTimeout = window.setTimeout(function(){
				getPreviewList($input, backendUrl, isLief, isKatalog, value,
						isKatalog ? 0 : 1,
						$searchForm.find('input[name=art]').val().toUpperCase(),
						$searchForm.find('input[name=SucheUeber]').val());
			}, 500);
		}
		return false;
	});
};

// initializes jquery vars
var initSearch = function()
{
	// Erweiterte Suche
	$('#ErwSucheToggle').click(function(){
		$(this).children('span').toggle(); // toggle +/-
		$('#ErwSuche').toggle();
	});

	$searchForm=$('#search-form');

	// Lieferanten
	$liefInput = $searchForm.find('input#input-lief');
	if ($liefInput.length == 1) {
		addInputEventHandler($liefInput, 'backend/LiefRequest.php', true, false);
	}

	// Artikelsuche/Katalogsuche
	$searchInput = $searchForm.find('#input-search');
	var isKatalog = ($searchInput.attr('name').search('Kat') == 0);
	addInputEventHandler($searchInput, 'backend/Vorschau' + (isKatalog ? 'K' : '') + 'Request.php', false, isKatalog);

	// global search cache
	searchCache = function() {
		var _keys = [], _values = [], // two arrays used as hashmap-like lookup table
			_getKey = function(data) { // returns a key for given parameters
				var s = '';
				if (typeof data == 'object') {
					for (i in data) {
						s += data[i] + ',';
					}
				}
				else { // string
					s = data;
				}
				//console.log('searchCache._getKey() key=' + s);
				return s;
			},
			_find = function(data) {
				var key = _getKey(data);
				for (var i=0; i<_keys.length; i++) {
					if (_keys[i] === key) { // cache hit
						//console.log('searchCache._find() key=' + key + ', value=', _values[i]);
						return _values[i];
					}
				}
				return null;
			};
		return {
			// add data and result to "cache"
			add: function(data, result) {
				if (_keys.length == maxSearchCacheEntries) {
					// cache is full, remove first element
					_keys.pop();
					_values.pop();
				}
				_keys.push(_getKey(data));
				_values.push(result);
			},
			// get cached result or null for given data
			get: function(data) {
				if (!data) return null;
				return _find(data);
			}
		};
	}();
};

/* ###  Lieferanten-/Artikel-/Katalogvorschau  ###################################### */
var getPreviewList = function($input, backendUrl, isLief, isKatalog, value, slimit, art, type) {

	// inner callback for (cached) json
	var _previewListCallback = function(json)
	{
		$el.wait.hide();
		if(!json || json.nohits){ // no result...
			$el.noResult.show();
			if (isLief) $el.input.focus().select();
			return;
		}

		// show result...
		$el.result.show();
		if (json.hits) {
			$el.result.children('div.search-result-hits').empty()
				.append('[' + json.hits + '] Treffer').show();
		}
		if (json.up !=null || json.down != null) {
			if (json.up != null) {
				$el.btns.eq(0).data('limit',json.up).css('display','block');
			}
			else {
				$el.btns.eq(0).hide();
			}
			if (json.down != null) {
				$el.btns.eq(1).data('limit',json.down).css('display','block');
			}
			else {
				$el.btns.eq(1).hide();
			}
		}

		if (json.data) { // fill result list

			if (isLief) { // Lieferanten
				if (json.data.length == 1) { // one result
					// fill input field and select search field
					$el.input.val(json.data);
					$searchInput.focus().select();
					return;
				}
				else { // result list
					var $s = $('<div />');
					$.each(json.data,function(){
						$s.append(getResultNode('' + this));
					});
					$el.resultList.empty().append($s.children()).show();
				}
			}
			else { // Katalog/Artikel
				var $s = $('<div />'); // dummy container
				$.each(json.data,function(){
					var str = isKatalog
						? (this[0] + ' [' + this[1] + '] Treffer')
						: this[1];
					$s.append( getResultNode(str).data('qResult', this[0]) );
				});
				$el.resultList.empty().append($s.children()).show();
			}
		}
	};
	
	var $el = $input.data('$el'),
		backendArgs = isLief ? {value : value} // Lieferanten
							: (isKatalog ? {value : value, // Katalog
											SLimit : slimit}
										: {value : value, // Artikel
											SLimit : slimit,
											Aufruf_art : art,
											SucheUeber : type,
											LiefName : (type == 4) ? $liefInput.val() : ''});
	// save args for search cache and up-/down-buttons
	$el.input.data('backendArgs', backendArgs);
	$el.noResult.hide();
	$el.result.children().andSelf().hide(); // hide: hits, up, down, result-list

	$el.wait.show();
	$el.preview.show();

	var cached = searchCache.get(backendArgs);
	if (cached) { // return cached data
		return _previewListCallback(cached);
	}
	// return data from backend URL
	$.getJSON(backendUrl, backendArgs, function(json){
			searchCache.add(backendArgs, json);
			_previewListCallback(json);
		}
	);
};