var Qs_Form_Element_Date = {

    timeoutHandle : null,
    eventTimeout : 1000,
    
    message: new qs.Message({
        'eng': {
        },
        'uk': {
        }
    }),
    options: {},

    init: function (id, options)
    {
        var displayId = Qs_Form_Element_Date.getDisplayId(id);
        var element = document.getElementById(displayId);
        if (!element) {
            alert('Qs_Form_Element_Date. Can not find element with id = ' + displayId);
            return false;
        }
        if (!element.tagName || element.tagName != 'INPUT') {
            alert('Qs_Form_Element_Date. Element (id = ' + displayId + ') is not "input"');
            return false;
        }
        if (element.type != 'text') {
            alert('Qs_Form_Element_Date. Element (id = ' + displayId + ') type is not "text"');
            return false;
        }
        options.onChangeMonthYear = Qs_Form_Element_Date.onChangeMonthYear;
        $(element).datepicker(options);
        var dateFormat = Qs_Form_Element_Date.getElementOption(id, 'dateFormat');
        var strFormat = dateFormat.replace(/y/g, 'yy');
        $(element).attr('maxlength', strFormat.length);
        
        $(element).tooltip({
            title: 'Date is in wrong format. Example: ' + $.datepicker.formatDate(dateFormat, new Date()),
            trigger: 'manual'
        });
        $(element).keyup(Qs_Form_Element_Date.onKeyUp);
        $(element).change(Qs_Form_Element_Date.onChange);

        return true;
    },

    getDisplayId: function (id)
    {
        var pos = id.lastIndexOf('-');
        var displayId = '';
        if (-1 != pos) {
            pos++;
            if (id.charAt(pos) != '_') {
                displayId = id.substr(0, pos) + '_' + id.substr(pos);
            } else {
                displayId = id;
            }
        } else {
            displayId = ((id.charAt(0) == '_') ? '' : '_')  + id;
        }
        return displayId;
    },

    getElementOptions: function (id)
    {
        var displayId = Qs_Form_Element_Date.getDisplayId(id);
        return $('#' + displayId).datepicker('option');
    },

    getElementOption: function (id, name)
    {
        var displayId = Qs_Form_Element_Date.getDisplayId(id);
        return $('#' + displayId).datepicker('option', name);
    },

    setElementOption: function (id, name, value)
    {
        var displayId = Qs_Form_Element_Date.getDisplayId(id);
        $('#' + displayId).datepicker('option', name, value);
    },

    setElementOptions: function (id, options)
    {
        for (var option in options) {
            Qs_Form_Element_Date.setOption(id, option, options[option]);
        }
    },

    callMethod: function (id, method, value)
    {
        var displayId = Qs_Form_Element_Date.getDisplayId(id);
        return $('#' + displayId).datepicker(method, value);
    },

    onKeyUp: function ()
    {
        Qs_Form_Element_Date.textChanged(this);
    },

    onChange: function ()
    {
        Qs_Form_Element_Date.textChanged(this);
    },

    textChanged: function (element)
    {
        clearTimeout(Qs_Form_Element_Date.timeoutHandle);
        Qs_Form_Element_Date.timeoutHandle = setTimeout(
            function(){Qs_Form_Element_Date.dateChanged(element);},
            Qs_Form_Element_Date.eventTimeout
        );
    },
    
    dateChanged: function (element)
    {
        Qs_Form_Element_Date.normalizeDate(element);
        var id = $(element).attr('id').substring(1);
        var displayId = Qs_Form_Element_Date.getDisplayId(id);
        var value = $('#' + displayId).val();
        try {
            if (Qs_Form_Element_Date.isValidDate(value)) {
                $(element).removeClass('error');
                var formatted = $.datepicker.parseDate(Qs_Form_Element_Date.getElementOption(id, 'dateFormat'), value);
                Qs_Form_Element_Date.callMethod(id, 'setDate', formatted);
                Qs_Form_Element_Date.hideTip(element);
            } else {
                if (value != '') {
                    $(element).addClass('error');
                    Qs_Form_Element_Date.showTip(element);
                }
                $('#' + id).val(value);
            }
        } catch (e) {
            $('#' + id).val(value);
        }
    },

    showTip: function (element)
    {
        $(element).tooltip('show');
    },

    hideTip: function (element)
    {
        $(element).tooltip('hide');
    },

    normalizeDate: function (element)
    {
        var id = Qs_Form_Element_Date.getDisplayId($(element).attr('id'));
        var format = Qs_Form_Element_Date.getElementOption(id, 'dateFormat').replace(/y/g, 'yy');
        var delimiters = format.replace(/[mdy]/gi, '');
        var delimiter = delimiters.charAt(0);
        for (var i = 0; i < element.value.length; i++) {
            if (format.charAt(i) == delimiter && element.value.charAt(i) != delimiter) {
                element.value = element.value.substring(0, i) + delimiter + element.value.substring(i);
            }
        }
        if (element.value.length > format.length) {
            element.value = element.value.substring(0, format.length);
        }
    },

    isValidDate: function (txtDate)
    {
        var objDate;
        var mSeconds;
        if (txtDate.length != 10)  {
            return false;
        }
        var day   = txtDate.substring(3,5)  - 0;
        var month = txtDate.substring(0,2)  - 1;
        var year  = txtDate.substring(6,10) - 0;
        if (txtDate.substring(2,3) != '/' || txtDate.substring(5,6) != '/' || year < 999 || year > 3000) {
            return false;
        }
        mSeconds = (new Date(year, month, day)).getTime();
        objDate = new Date();
        objDate.setTime(mSeconds);
        if (objDate.getFullYear() != year)  return false;
        if (objDate.getMonth()    != month) return false;
        if (objDate.getDate()     != day)   return false;
        return true;
    },

    onChangeMonthYear: function (year, month, inst)
    {
        var day = null;
        if (1 <= inst.currentDay) {
            var daysInMonths = new Date(year, month, 0).getDate();
            day = (inst.currentDay <= daysInMonths) ? inst.currentDay : daysInMonths;
        } else {
            day = new Date().getDate();
        }
        var date = new Date(year, month - 1,  day);
        var id = inst.input.attr('id');
        $('#' + id).datepicker('setDate', date);
    }
};