/*! Copyright (c) 2010 Brandon Aaron (http://brandonaaron.net)
 * Licensed under the MIT License (LICENSE.txt).
 *
 * Version 0.2
 */
(function($){

	/*
	 * Creates an instance of a SpellChecker for each matched element.
	 * The SpellChecker has several configurable options.
	 *  - lang: the 2 letter language code, defaults to en for english
	 *  - events: a space separated string of events to use, default is 'keypress blur paste'
	 *  - autocheck: number of milliseconds to check spelling after a key event, default is 750.
	 *  - url: url of the spellcheck service on your server, default is spellcheck.php
	 *  - ignorecaps: 1 to ignore words with all caps, 0 to check them
	 *  - ignoredigits: 1 to ignore digits, 0 to check them
	 */
	$.fn.spellcheck = function(options) {
		return this.each(function() {
			var $this = $(this);
			if ( !$this.is('[type=password]') && !$(this).data('spellchecker') )
				$(this).data('spellchecker', new $.SpellChecker(this, options));
		});
	};

	/**
	 * Forces a spell check on an element that has an instance of SpellChecker.
	 */
	$.fn.checkspelling = function() {
		return this.each(function() {
			var spellchecker = $(this).data('spellchecker');
			spellchecker && spellchecker.checkSpelling();
		});
	};


	$.SpellChecker = function(element, options) {
		this.$element = $(element);
		this.options = $.extend({
				lang: 'en',
				autocheck: 750,
				events: 'keypress blur paste',
				url: '/spellcheck.php',
				ignorecaps: 1,
				ignoredigits: 1
		}, options);
		this.bindEvents();
	};

	$.SpellChecker.prototype = {
		bindEvents: function() {
			if ( !this.options.events ) return;
			var self = this, timeout;
			this.$element.bind(this.options.events, function(event) {
				if ( /^key[press|up|down]/.test(event.type) ) {
					if ( timeout ) clearTimeout(timeout);
					timeout = setTimeout(function() { self.checkSpelling(); }, self.options.autocheck);
				} else
				self.checkSpelling(); 
			});
		},

		checkSpelling: function() {
			var prevText = this.text, text = this.$element.val(), self = this;
			if ( prevText === text ) return;
			this.text = this.$element.val();
			$.get(this.options.url, { 
					text: this.text, 
					lang: this.options.lang,
					ignorecaps: this.options.ignorecaps,
					ignoredigits: this.options.ignoredigits
			}, 
			function(r) { self.parseResults(r); }, 
			'xml'
			);
		},

		parseResults: function(results) {
			var self = this;
			this.results = [];
			$(results).find('c').each(function() {
				var $this = $(this),
				offset = $this.attr('o'),
				length = $this.attr('l');
				self.results.push({
						word: self.text.substr(offset, length),
						suggestions: $this.text().split(/\s/)
				});
			});
			this.displayResults();
		},

		displayResults: function() {
			$('#spellcheckresults').remove();
			if ( !this.results.length ) return;
			var $container = $('<div id="spellcheckresults"></div>').appendTo('body'),
			dl = [], self = this, offset = this.$element.offset(), height = this.$element[0].offsetHeight, i, k;
			for ( i=0; i<this.results.length; i++ ) {
				var result = this.results[i], suggestions = result.suggestions;
				dl.push('<dl><dt>'+result.word+'</dt>');
				for ( k=0; k<suggestions.length; k++ )
					dl.push('<dd>'+suggestions[k]+'</dd>');
				dl.push('<dd class="ignore">ignore</dd></dl>');
			}
			$container.append(dl.join('')).find('dd').bind('click', function(event) {
				var $this = $(this), $parent = $this.parent();
				if ( !$this.is('.ignore') )
					self.$element.val( self.$element.val().replace( $parent.find('dt').text(), $this.text() ) );
				$parent.remove();
				if ( $('#spellcheckresults').is(':empty') )
				$('#spellcheckresults').remove();
				this.blur();
			}).end().css({ top: offset.top + height, left: offset.left });
		}

	};
})(jQuery);