/*
 * Copyright (c) 2006 Sam Collett (http://www.texotela.co.uk)
 * Licensed under the MIT License:
 * http://www.opensource.org/licenses/mit-license.php
 */

/*
 * A time picker for jQuery
 * Based on original timePicker by Sam Collet (http://www.texotela.co.uk)
 * @name     timePicker
 * @version  0.1
 * @author   Anders Fajerson (http://perifer.se)
 * @example  $("#mytime").timePicker();
 * @example  $("#mytime").timePicker({step:30, startTime:"15:00", endTime:"18:00"});
 */

(function($){

  $.fn.timePicker = function(options) {
	// Build main options before element iteration
	  var settings = $.extend({}, $.fn.timePicker.defaults, options);

	return this.each(function() {
	  $.timePicker(this, settings);
	});
  };

  $.timePicker = function (elm, settings) {
	var elm = $(elm)[0];
	return elm.timePicker || (elm.timePicker = new jQuery._timePicker(elm, settings));
  };

  $._timePicker = function(elm, settings) {

	var tpOver = false;
	var startTime = normaliseTime(settings.startTime);
	var endTime = normaliseTime(settings.endTime);

	$(elm).attr('autocomplete', 'OFF'); // Disable browser autocomplete

	var times = [];
	var time = new Date(startTime); // Create a new date object.
	while(time <= endTime) {
	  times[times.length] = formatTime(time, settings);
	  time = new Date(time.setMinutes(time.getMinutes() + settings.step));
	}

	var $tpDiv = $('<div class="time-picker'+ (settings.show24Hours ? '' : ' time-picker-12hours') +'"></div>');
	var $tpList = $('<ul></ul>');

	// Build the list.
	for(var i = 0; i < times.length; i++) {
	  $tpList.append("<li>" + times[i] + "</li>");
	}
	$tpDiv.append($tpList);
	// Store element offset.
	var elmOffset = $(elm).offset();

	// Append the timPicker to the body and position it.
	//$tpDiv.appendTo("body").css({'top':elmOffset.top, 'left':elmOffset.left}).hide();

	// Append the timPicker to the time choices container
	$(elm).siblings(".timechoices").append($tpDiv);

	// hide timPicker
	$tpDiv.hide();

	$("li", $tpList).unbind().mouseover(function() {
	  $("li.selected", $tpDiv).removeClass("selected");  // TODO: only needs to run once.
	  $(this).addClass("selected");
	}).mousedown(function() {
	   tpOver = true;
	}).click(function() {
	  setTimeVal(elm, this, $tpDiv, settings);
	  tpOver = false;
	});

	// Store ananymous function in variable since it's used twice.
	var showPicker = function() {
	  $tpDiv.show(); // Show picker.
	  $tpDiv.mouseover(function() { // Have to use mouseover instead of mousedown because of Opera
		tpOver = true;
	  }).mouseout(function() {
		tpOver = false;
	  });
	  $("li", $tpDiv).removeClass("selected");

	  // Try to find a time in the list that matches the entered time.
	  var time = this.value ? timeStringToDate(this.value, settings) : startTime;
	  var startMin = startTime.getHours() * 60 + startTime.getMinutes();
	  var min = (time.getHours() * 60 + time.getMinutes()) - startMin;

	  // number of steps selected time is (example: if start time is 9:00 and interval is 30, and 11:00 is selected, steps is 4)
	  var steps = Math.round(min / settings.step);

	  // convert time selected to date object
	  var roundTime = normaliseTime(new Date(2001, 0, 0, 0, (steps * settings.step + (startMin)), 0));

	  // find next time that should be selected based on current time
	  roundTime = (startTime < roundTime && roundTime <= endTime) ? roundTime : startTime;

	  	// find li that contains exactly the time
		var $matchedTime = $tpDiv.find("li").filter(function(){
			return $(this).text() == formatTime(roundTime, settings);
		});

	  if ($matchedTime.length) {
		$matchedTime.addClass("selected");
		// Scroll to matched time.
		$tpDiv[0].scrollTop = $matchedTime[0].offsetTop;
	  }
	};

	$(elm).unbind().focus(showPicker).click(showPicker)
	// Hide timepicker on blur
	.blur(function() {
	  if (!tpOver && $tpDiv[0].parentNode) { // Don't remove when timePicker is clicked or when already removed
		$tpDiv.hide();
	  }
	})

	// Key support
	.keypress(function(e) {
	  switch (e.keyCode) {
		case 38: // Up arrow.
		case 63232: // Safari up arrow.
		  var $selected = $("li.selected", $tpList);
		  var prev = $selected.prev().addClass("selected")[0];
		  if (prev) {
			$selected.removeClass("selected");
			$tpDiv[0].scrollTop = prev.offsetTop;
		  }
		  return false;
		  break;
		case 40: // Down arrow.
		case 63233: // Safari down arrow.
		  var $selected = $("li.selected", $tpList);
		  var next = $selected.length ? $selected.next().addClass("selected")[0] : $("li:first").addClass("selected")[0];
		  if (next) {
			$selected.removeClass("selected");
			$tpDiv[0].scrollTop = next.offsetTop;
		  }
		  return false;
		  break;
		case 13: // Enter
		  if (!$tpDiv.is(":hidden")) {
			var sel = $("li.selected", $tpList)[0];
			setTimeVal(elm, sel, $tpDiv, settings);
			return false;
		  }
		  break;
	  }
	});

	// Helper function to get an inputs current time as Date object.
	// Returns a Date object.
	this.getTime = function() {
	  return timeStringToDate(elm.value, settings);
	};
	// Helper function to set a time input.
	// Takes a Date object.
	this.setTime = function(time) {
	  elm.value = formatTime(normaliseTime(time), settings);
	  // Trigger element's change events.
	  $(elm).change();
	};

  }; // End fn;

  // Plugin defaults.
  $.fn.timePicker.defaults = {
	step:30,
	startTime: new Date(0, 0, 0, 0, 0, 0),
	endTime: new Date(0, 0, 0, 23, 30, 0),
	separator: ':',
	show24Hours: false
  };

  // Private functions.

  function setTimeVal(elm, sel, $tpDiv, settings) {
	// Update input field
	elm.value = $(sel).text();
	// Trigger element's change events.
	$(elm).change();
	// Keep focus for all but IE (which doesn't like it)
	if (!$.browser.msie) {
	  elm.focus();
	}
	// Hide picker
	$tpDiv.hide();
  }

	function formatTime(time, settings)
	{
		var h = time.getHours();
		var hours = settings.show24Hours ? h : (((h + 11) % 12) + 1);
		var minutes = time.getMinutes();

		return hours + settings.separator + formatNumber(minutes) + (settings.show24Hours ? '' : ((h < 12) ? 'am' : 'pm'));
	}

	function formatNumber(value) {
		return (value < 10 ? '0' : '') + value;
	}

function timeStringToDate(input, settings)
{
	if (input)
	{
		var array = input.split(settings.separator);
		var hours = parseFloat(array[0]);

		if (array[1].indexOf("pm") > -1)
		{
			if (hours != 12)
			{
				hours = hours + 12;
			}
		}
		else
		{
			if (hours == 12)
			{
				hours = 0
			}
		}

		var minutes = parseFloat(array[1]);
		var time = new Date(0, 0, 0, hours, minutes, 0);

		return normaliseTime(time);
	}

	return null;
}

  /* Normalise time object to a common date. */
	function normaliseTime(time) {
		time.setFullYear(2001);
		time.setMonth(0);
		time.setDate(0);
		return time;
	}

})(jQuery);