/*
* 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();
        var rElm = elm;
        // Append the timPicker to the body and position it.
        $tpDiv.appendTo('body').css({ 'top': elmOffset.top, 'left': elmOffset.left }).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() {
            // Store element offset.
            var elmOffset = $(rElm).offset();
            var elmHeight = $(rElm).outerHeight();
            // Append the timePicker to the body and position it.
            $tpDiv.css({ 'top': elmOffset.top + parseInt(elmHeight), 'left': elmOffset.left })
            $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;
            var steps = Math.round(min / settings.step);
            var roundTime = normaliseTime(new Date(2001, 0, 0, 0, (steps * settings.step + (startMin)), 0));
            roundTime = (startTime < roundTime && roundTime < endTime) ? roundTime : startTime;

            var $matchedTime = $("li:contains(" + formatTime(roundTime, settings) + ")", $tpDiv);

            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: true
    };

    // 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 formatNumber(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]);
            var minutes = parseFloat(array[1]);
            if (input.indexOf("PM") >= 0 && hours < 12) {
                hours += 12;
            } else if (hours == 12) {
                hours = 0;
            }
            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);