// qs_score - Quicksilver Score
// 
// A port of the Quicksilver string ranking algorithm
// 
// "hello world".score("axl") //=> 0.0
// "hello world".score("ow") //=> 0.6
// "hello world".score("hello world") //=> 1.0
//
// Tested in Firefox 2 and Safari 3
//
// The Quicksilver code is available here
// http://code.google.com/p/blacktree-alchemy/
// http://blacktree-alchemy.googlecode.com/svn/trunk/Crucible/Code/NSString+BLTRRanking.m
//
// The MIT License
// 
// Copyright (c) 2008 Lachie Cox
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.


String.prototype.score = function(abbreviation,offset) {
  offset = offset || 0 // TODO: I think this is unused... remove
 
  if(abbreviation.length == 0) return 0.9
  if(abbreviation.length > this.length) return 0.0

  for (var i = abbreviation.length; i > 0; i--) {
    var sub_abbreviation = abbreviation.substring(0,i)
    var index = this.indexOf(sub_abbreviation)


    if(index < 0) continue;
    if(index + abbreviation.length > this.length + offset) continue;

    var next_string       = this.substring(index+sub_abbreviation.length)
    var next_abbreviation = null

    if(i >= abbreviation.length)
      next_abbreviation = ''
    else
      next_abbreviation = abbreviation.substring(i)
 
    var remaining_score   = next_string.score(next_abbreviation,offset+index)
 
    if (remaining_score > 0) {
      var score = this.length-next_string.length;

      if(index != 0) {
        var j = 0;

        var c = this.charCodeAt(index-1)
        if(c==32 || c == 9) {
          for(var j=(index-2); j >= 0; j--) {
            c = this.charCodeAt(j)
            score -= ((c == 32 || c == 9) ? 1 : 0.15)
          }

          // XXX maybe not port this heuristic
          // 
          //          } else if ([[NSCharacterSet uppercaseLetterCharacterSet] characterIsMember:[self characterAtIndex:matchedRange.location]]) {
          //            for (j = matchedRange.location-1; j >= (int) searchRange.location; j--) {
          //              if ([[NSCharacterSet uppercaseLetterCharacterSet] characterIsMember:[self characterAtIndex:j]])
          //                score--;
          //              else
          //                score -= 0.15;
          //            }
        } else {
          score -= index
        }
      }
   
      score += remaining_score * next_string.length
      score /= this.length;
      return score
    }
  }
  return 0.0
}

jQuery(function ($) {
	$.fn.quicksearch = function (opt) {
		
		function is_empty(i) 
		{
			return (i === null || i === undefined || i === false) ? true: false;
		}
		
		function strip_html(input)
		{
			var regexp = new RegExp(/\<[^\<]+\>/g);
			var output = input.replace(regexp, "");
			output = $.trim(output.toLowerCase().replace(/\n/, '').replace(/\s{2,}/, ' '));
			return output;
		}
		
		function get_key()
		{
			var input = strip_html($('input[rel="' + options.randomElement + '"]').val());
			
			if (input.indexOf(' ') === -1)
			{
				return input;
			}
			else
			{
				return input.split(" ");
			}
		}
		
		function test_key(k, value, type)
		{
			if (type === "string")
			{
				return test_key_string(k, value);
			}
			else
			{
				return test_key_arr(k, value);
			}
		}
		
		function test_key_string(k, value)
		{
			return (value.indexOf(k) > -1);
		}
		
		function test_key_arr(k, value)
		{
			for (var i = 0; i < k.length; i++) {
				var test = value.indexOf(k[i]);	
				if (test === -1) {	
					return false;
				}
			}			
			return true;
		}
		
		function select_element(el) 
		{
			if (options.hideElement === "grandparent") 
			{
				return $(el).parent().parent();
			} 
			else if (options.hideElement === "parent") 
			{
				return $(el).parent();
			} 
			else
			{
				return $(el);
			}
		}
		
		function stripe(el)
		{
			if (doStripe)
			{
				var i = 0;
				select_element(el).filter(':visible').each(function () {
					
					for (var j = 0; j < stripeRowLength; j++)
					{
						if (i === j)
						{
							$(this).addClass(options.stripeRowClass[i]);
							
						}
						else
						{
							$(this).removeClass(options.stripeRowClass[j]);
						}
					}
					i = (i + 1) % stripeRowLength;
				});
			}
		}
		
		function fix_widths(el)
		{
			$(el).find('td').each(function () {
				$(this).attr('width', parseInt($(this).css('width')));
			});
		}
		
		function loader(o) {
			if (options.loaderId) 
			{
				var l = $('input[rel="' + options.randomElement + '"]').parent().find('.loader');
				if (o === 'hide') 
				{
					l.hide();
				} 
				else 
				{
					l.show();
				}
			}			
		}
		
		function place_form() {
			var formPosition = options.position;
			var formAttached = options.attached;

			if (formPosition === 'before') {
				$(formAttached).before(make_form());
			} else if (formPosition === 'prepend') {
				$(formAttached).prepend(make_form());
			} else if (formPosition === 'append') {
				$(formAttached).append(make_form());
			} else {
				$(formAttached).after(make_form());
			}
		}
				
		function make_form_label()
		{
			if (!is_empty(options.labelText)) {
				return '<label for="' + options.randomElement + '" '+
							'class="' + options.labelClass + '">'
							+ options.labelText
							+ '</label> ';	
			}
			return '';
		}
		
		function make_form_input()
		{
			var val = (!is_empty(options.inputText)) ? options.inputText : ""
			return '<input type="text" value="' + val + '" rel="' + options.randomElement  + '" class="' + options.inputClass + '" id="' + options.randomElement + '" /> ';
		}
		
		function make_form_loader()
		{
			if (!is_empty(options.loaderImg)) {
				return '<img src="' + options.loaderImg + '" alt="Loading" id="' + options.loaderId + '" class="' + options.loaderClass + '" />';
			} else {
				return '<span id="' + options.loaderId + '" class="' + options.loaderClass + '">' + options.loaderText + '</span>';
			}
		}
		
		function make_form()
		{
			var f = (!options.isFieldset) ? 'form' : 'fieldset';
			return '<' + f + ' action="#" ' + 'id="'+ options.formId + '" ' + 'class="quicksearch">' +
						make_form_label() +	make_form_input() + make_form_loader() +
					'</' + f + '>';
		}
			
		function focus_on_load()
		{
			$('input[rel="' + options.randomElement + '"]').get(0).focus();
		}
		
		function toggle_text() {
			$('input[rel="' + options.randomElement + '"]').focus(function () {
				if ($(this).val() === options.inputText) {
					$(this).val('');
				}
			});
			$('input[rel="' + options.randomElement + '"]').blur(function () {
				if ($(this).val() === "") {
					$(this).val(options.inputText);
				}
			});
		}
		
		function get_cache(el) 
		{
			return $(el).map(function(){
				return strip_html(this.innerHTML);
			});
		}
		
		function init()
		{
			place_form();
			if (options.fixWidths) fix_widths(el);
			if (options.focusOnLoad) focus_on_load();
			if (options.inputText != "" && options.inputText != null) toggle_text();
			
			cache = get_cache(el);
			
			stripe(el);
			loader('hide');
		}
		
		function qs() 
		{
			clearTimeout(timeout);
			timeout = setTimeout(function () {
				
				loader('show');
				
				setTimeout(function () {
					options.onBefore();
					
					var k = get_key();
					var k_type = (typeof k);
					var i = 0;
					
					k = options.filter(k);
					
					if (k != "")
					{
						if (typeof score[k] === "undefined")
						{
							score[k] = new Array();
							cache.each(function (i) {
								if (test_key(k, cache[i], k_type))
								{
									score[k][i] = true;
								}
							});
						}
						
						if (score[k].length === 0)
						{
							select_element(el).hide();
						}
						else
						{
							$(el).each(function (i) {
								if (score[k][i])
								{
									select_element(this).show();
								}
								else
								{
									select_element(this).hide();
								}
							});
							
						}
					}
					else
					{
						select_element(el).show();
					}
				
					stripe(el);
				}, options.delay/2);
				
				setTimeout( function () { 
					loader('hide');
				}, options.delay/2);
				
				options.onAfter();
				
			}, options.delay/2);
		}
		
		var options = $.extend({
			position: 'prepend',
			attached: 'body',
			formId: 'quicksearch',
			labelText: 'Quick Search',
			labelClass: 'qs_label',
			inputText: null,
			inputClass: 'qs_input',
			loaderId: 'loader',
			loaderClass: 'loader',
			loaderImg: null,
			loaderText: 'Loading...',
			stripeRowClass: null,
			hideElement: null,
			delay: 500,
			focusOnLoad: false,
			onBefore: function () { },
			onAfter: function () { },
			filter: function (i) { 
				return i;
			},
			randomElement: 'qs' + Math.floor(Math.random() * 1000000),
			isFieldset: false,
			fixWidths: false
		}, opt);
		
		var timeout;
		var score = {};
		var stripeRowLength = (!is_empty(options.stripeRowClass)) ? options.stripeRowClass.length : 0;
		var doStripe = (stripeRowLength > 0) ? true : false;
		var el = this;
		var cache;
		var selector = $(this).selector;
		
		$.fn.extend({
			reset_cache: function () {
				el = $(selector);
				cache = get_cache(el);
			}
		});
		
		init();
		
		$('input[rel="' + options.randomElement + '"]').keydown(function (e) {
			var keycode = e.keyCode;
			if (!(keycode === 9 || keycode === 13 || keycode === 16 || keycode === 17 || keycode === 18 || keycode === 38 || keycode === 40 || keycode === 224))
			{
				qs();
			}
		});
		
		$('form.quicksearch, fieldset.quicksearch').submit( function () { return false; });
		
		return this;
	};
});