(function ($) {

	$.alerts = {

		// These properties can be read/written by accessing $.alerts.propertyName from your scripts at any time

		verticalOffset    : -75,                // vertical offset of the dialog from center screen, in pixels
		horizontalOffset  : 0,                // horizontal offset of the dialog from center screen, in pixels/
		repositionOnResize: true,           // re-centers the dialog on window resize
		overlayOpacity    : .01,                // transparency level of overlay
		overlayColor      : '#FFF',               // base color of overlay
		draggable         : true,                    // make the dialogs draggable (requires UI Draggables plugin)
		okButton          : '&nbsp;OK&nbsp;',         // text for the OK button
		cancelButton      : '&nbsp;Cancel&nbsp;', // text for the Cancel button
		dialogClass       : null,                  // if specified, this class will be applied to all dialogs

		// Public methods

		alert: function (message, title, callback) {
			if (title == null) title = 'Alert';
			$.alerts._show(title, message, null, 'alert', function (result) {
				if (callback) callback(result);
			});
		},

		confirm: function (message, title, callback) {
			if (title == null) title = 'Confirm';
			$.alerts._show(title, message, null, 'confirm', function (result) {
				if (callback) callback(result);
			});
		},

		prompt: function (message, value, title, callback) {
			if (title == null) title = 'Prompt';
			$.alerts._show(title, message, value, 'prompt', function (result) {
				if (callback) callback(result);
			});
		},

		// Private methods

		_show: function (title, msg, value, type, callback) {

			$.alerts._hide();
			$.alerts._overlay('show');

			$("BODY").append(
				'<div id="popup_container">' +
					'<h1 id="popup_title"></h1>' +
					'<div id="popup_content">' +
					'<div id="popup_message"></div>' +
					'</div>' +
					'</div>');

			if ($.alerts.dialogClass) $("#popup_container").addClass($.alerts.dialogClass);

			// IE6 Fix
			var pos = ($.browser.msie && parseInt($.browser.version) <= 6 ) ? 'absolute' : 'fixed';

			$("#popup_container").css({
				position: pos,
				zIndex  : 99999,
				padding : 0,
				margin  : 0
			});

			$("#popup_title").text(title);
			$("#popup_content").addClass(type);
			$("#popup_message").text(msg);
			$("#popup_message").html($("#popup_message").text().replace(/\n/g, '<br />'));

			$("#popup_container").css({
				minWidth: $("#popup_container").outerWidth(),
				maxWidth: $("#popup_container").outerWidth()
			});

			$.alerts._reposition();
			$.alerts._maintainPosition(true);

			switch (type) {
				case 'alert':
					$("#popup_message").after('<div id="popup_panel"><input type="button" value="' + $.alerts.okButton + '" id="popup_ok" /></div>');
					$("#popup_ok").click(function () {
						$.alerts._hide();
						callback(true);
					});
					$("#popup_ok").focus().keypress(function (e) {
						if (e.keyCode == 13 || e.keyCode == 27) $("#popup_ok").trigger('click');
					});
					break;
				case 'confirm':
					$("#popup_message").after('<div id="popup_panel"><input type="button" value="' + $.alerts.okButton + '" id="popup_ok" /> <input type="button" value="' + $.alerts.cancelButton + '" id="popup_cancel" /></div>');
					$("#popup_ok").click(function () {
						$.alerts._hide();
						if (callback) callback(true);
					});
					$("#popup_cancel").click(function () {
						$.alerts._hide();
						if (callback) callback(false);
					});
					$("#popup_ok").focus();
					$("#popup_ok, #popup_cancel").keypress(function (e) {
						if (e.keyCode == 13) $("#popup_ok").trigger('click');
						if (e.keyCode == 27) $("#popup_cancel").trigger('click');
					});
					break;
				case 'prompt':
					$("#popup_message").append('<br /><input type="text" size="30" id="popup_prompt" />').after('<div id="popup_panel"><input type="button" value="' + $.alerts.okButton + '" id="popup_ok" /> <input type="button" value="' + $.alerts.cancelButton + '" id="popup_cancel" /></div>');
					$("#popup_prompt").width($("#popup_message").width());
					$("#popup_ok").click(function () {
						var val = $("#popup_prompt").val();
						$.alerts._hide();
						if (callback) callback(val);
					});
					$("#popup_cancel").click(function () {
						$.alerts._hide();
						if (callback) callback(null);
					});
					$("#popup_prompt, #popup_ok, #popup_cancel").keypress(function (e) {
						if (e.keyCode == 13) $("#popup_ok").trigger('click');
						if (e.keyCode == 27) $("#popup_cancel").trigger('click');
					});
					if (value) $("#popup_prompt").val(value);
					$("#popup_prompt").focus().select();
					break;
			}

			// Make draggable
			if ($.alerts.draggable) {
				try {
					$("#popup_container").draggable({ handle: $("#popup_title") });
					$("#popup_title").css({ cursor: 'move' });
				} catch (e) { /* requires jQuery UI draggables */
				}
			}
		},

		_hide: function () {
			$("#popup_container").remove();
			$.alerts._overlay('hide');
			$.alerts._maintainPosition(false);
		},

		_overlay: function (status) {
			switch (status) {
				case 'show':
					$.alerts._overlay('hide');
					$("BODY").append('<div id="popup_overlay"></div>');
					$("#popup_overlay").css({
						position  : 'absolute',
						zIndex    : 99998,
						top       : '0px',
						left      : '0px',
						width     : '100%',
						height    : $(document).height(),
						background: $.alerts.overlayColor,
						opacity   : $.alerts.overlayOpacity
					});
					break;
				case 'hide':
					$("#popup_overlay").remove();
					break;
			}
		},

		_reposition: function () {
			var top = (($(window).height() / 2) - ($("#popup_container").outerHeight() / 2)) + $.alerts.verticalOffset;
			var left = (($(window).width() / 2) - ($("#popup_container").outerWidth() / 2)) + $.alerts.horizontalOffset;
			if (top < 0) top = 0;
			if (left < 0) left = 0;

			// IE6 fix
			if ($.browser.msie && parseInt($.browser.version) <= 6) top = top + $(window).scrollTop();

			$("#popup_container").css({
				top : top + 'px',
				left: left + 'px'
			});
			$("#popup_overlay").height($(document).height());
		},

		_maintainPosition: function (status) {
			if ($.alerts.repositionOnResize) {
				switch (status) {
					case true:
						$(window).bind('resize', $.alerts._reposition);
						break;
					case false:
						$(window).unbind('resize', $.alerts._reposition);
						break;
				}
			}
		}

	}

	// Shortuct functions
	jAlert = function (message, title, callback) {
		$.alerts.alert(message, title, callback);
	}

	jConfirm = function (message, title, callback) {
		$.alerts.confirm(message, title, callback);
	};

	jPrompt = function (message, value, title, callback) {
		$.alerts.prompt(message, value, title, callback);
	};

})(jQuery);