function DatePicker() {
    this.dataRow = 0;
    this.dataColumn = "";
    this.dataColumnTh = "";
    this.dataObject = null;
    this.currentElement = null;
    this.Gcoop = null;
    this.callbackFunction = null;

    this.PickDs = function (dsObject, row, column, callFunction) {
        var el = dsObject.GetElement(row, column);
        this.dataRow = row;
        this.dataColumn = column;
        this.dataColumnTh = "";
        this.dataObject = dsObject;
        this.currentElement = el;
        try {
            if (callFunction == undefined || callFunction == null) {
                this.callbackFunction = null;
            } else {
                this.callbackFunction = callFunction;
            }
        } catch (err) {
            this.callbackFunction = null;
        }
        this.SecondPick();
    }

    this.PickDw = function (dwObject, row, columnE, columnT, callFunction) {
        var el = this.Gcoop.GetElForm(columnT + "_" + (row - 1));
        this.dataRow = row;
        this.dataColumn = columnE;
        this.dataColumnTh = columnT;
        this.dataObject = dwObject;
        this.currentElement = el;
        try {
            if (callFunction == undefined || callFunction == null) {
                this.callbackFunction = null;
            } else {
                this.callbackFunction = callFunction;
            }
        } catch (err) {
            this.callbackFunction = null;
        }
        this.SecondPick();
    }

    this.SecondPick = function () {
        var valueEl = "";
        var theDate = null;
        try {
            valueEl = this.currentElement.value;
            if (valueEl == null || valueEl == undefined) {
                valueEl = "";
            }
        } catch (err) {
            valueEl = "";
        }
        if (valueEl.length == 8) {
            try {
                if (valueEl != "00000000") {
                    var d = this.Gcoop.ParseInt(valueEl.substr(0, 2));
                    var m = this.Gcoop.ParseInt(valueEl.substr(2, 2));
                    var yyyy = this.Gcoop.ParseInt(valueEl.substr(4)) - 543;
                    theDate = new Date();
                    theDate.setFullYear(yyyy, m - 1, d);
                }
            } catch (err) {
                theDate = null;
            }
        } else if (valueEl.length == 10) {
            try {
                if (valueEl != "00/00/0000") {
                    var d = this.Gcoop.ParseInt(valueEl.substr(0, 2));
                    var m = this.Gcoop.ParseInt(valueEl.substr(3, 2));
                    var yyyy = this.Gcoop.ParseInt(valueEl.substr(6)) - 543;
                    theDate = new Date();
                    theDate.setFullYear(yyyy, m - 1, d);
                }
            } catch (err) {
                theDate = null;
            }
        }
        this.PerformCarlendar(theDate);
    }

    this.PerformCarlendar = function (performDate) {
        var persisDate = new Date();
        if (performDate == null || performDate == undefined) {
            performDate = null;
        } else {
            persisDate = performDate;
        }
        this.SetFocusDate(persisDate);
        this.SetOutputDate(performDate);
        this.ShowCarlendar();
    }

    this.SetFocusDate = function (focusDate) {
        var yyyy = focusDate.getFullYear();
        var m = focusDate.getMonth();
        var d = focusDate.getDate();

        var dtFirst = new Date();
        dtFirst.setFullYear(yyyy, m, 1);

        var firstDay = dtFirst.getDay();
        firstDay--;
        if (firstDay < 0) firstDay = 6;

        var lastDay = 31;
        if (m == 3 || m == 5 || m == 8 || m == 10) {
            lastDay = 30;
        } else if (m == 1) {
            lastDay = 28;
            if (yyyy % 4 == 0) {
                lastDay = 29;
            }
        }
        var dd = 0;
        for (var i = 0; i < 42; i++) {
            if (i >= firstDay) {
                dd++;
            }
            if (dd > 0 && dd <= lastDay) {
                document.getElementById("divDayPickerIndex" + i).innerHTML = dd + "";
                if (dd == d) {
                    document.getElementById("divDayPickerIndex" + i).style.backgroundColor = "rgb(255,200,211)";
                } else {
                    document.getElementById("divDayPickerIndex" + i).style.backgroundColor = "rgb(211,231,255)";
                }
            } else {
                document.getElementById("divDayPickerIndex" + i).innerHTML = "";
                document.getElementById("divDayPickerIndex" + i).style.backgroundColor = "rgb(211,231,255)";
            }
        }
    }

    this.SetOutputDate = function (dtOutput) {
        var yyyy = 0;
        var m = 0;
        var d = 0;

        if (dtOutput != null) {
            yyyy = dtOutput.getFullYear() + 543;
            m = dtOutput.getMonth() + 1;
            d = dtOutput.getDate();
        }

        document.getElementById("tbDatePickerDay").value = d;
        document.getElementById("tbDatePickerMonth").value = m;
        document.getElementById("tbDatePickerYear").value = yyyy;

        this.SetOutputSelect("ddDatePickerDay", d);
        this.SetOutputSelect("ddDatePickerMonth", m);
        this.SetOutputSelect("ddDatePickerYear", yyyy);
    }

    this.SetOutputSelect = function (id, value) {
        var val = value + "";
        var sel = document.getElementById(id);
        for (var i = 0; i < sel.options.length; ++i) {
            if (sel.options[i].value == val) {
                sel.selectedIndex = i;
                break;
            }
        }
    }

    this.ShowCarlendar = function () {
        var position = Gcoop.GetObjectPosition(this.currentElement);
        var top = Math.ceil(position[0]) + 20;
        var left = Math.ceil(position[1]);
        var lastPosition = Gcoop.GetObjectPosition(document.getElementById("theLastObject"));
        var lastLeft = Math.ceil(lastPosition[1]);
        var lastTop = Math.ceil(lastPosition[0]);
        if ((left + 260) > lastLeft) {
            left = lastLeft - 270;
        }
        if (top + 210 > lastTop) {
            top = lastTop - 210;
        }
        document.getElementById("divCalendarPicker").style.position = "absolute";
        document.getElementById("divCalendarPicker").style.top = top + "px";
        document.getElementById("divCalendarPicker").style.left = left + "px";
        document.getElementById("divCalendarPicker").style.visibility = "visible";
        document.getElementById("divCalendarPicker").style.zIndex = "10";
    }

    this.Cancel = function () {
        this.currentElement = null;
        this.dataRow = 0;
        this.dataColumn = "";
        this.dataColumnTh = "";
        this.dataObject = null;
        this.callbackFunction = null;
        document.getElementById("divCalendarPicker").style.position = "absolute";
        document.getElementById("divCalendarPicker").style.top = 0 + "px";
        document.getElementById("divCalendarPicker").style.left = 0 + "px";
        document.getElementById("divCalendarPicker").style.visibility = "hidden";
        document.getElementById("divCalendarPicker").style.zIndex = "-1";
    }

    this.VerifyDate = function (yyyy, m, d, isAlert) {
        var newD = d;
        if (m == 1) {
            if (yyyy % 4 == 0) {
                if (d > 29) {
                    newD = 29;
                    if (isAlert) {
                        alert("ไม่มีวันที่ " + d + "/" + (m + 1) + "/" + (yyyy + 543) + " ในระบบปฏิทิน");
                    }
                }
            } else {
                if (d > 28) {
                    newD = 28;
                    if (isAlert) {
                        alert("ไม่มีวันที่ " + d + "/" + (m + 1) + "/" + (yyyy + 543) + " ในระบบปฏิทิน");
                    }
                }
            }
        } else if (m == 3 || m == 5 || m == 8 || m == 10) {
            if (d > 30) {
                newD = 30;
                if (isAlert) {
                    alert("ไม่มีวันที่ " + d + "/" + (m + 1) + "/" + (yyyy + 543) + " ในระบบปฏิทิน");
                }
            }
        }
        var newData = new Date();
        newData.setFullYear(yyyy, m, newD);
        return newData;
    }

    this.IsEqualTextBox = function (dtTest) {
        var elDate = document.getElementById("tbDatePickerDay");
        var elMonth = document.getElementById("tbDatePickerMonth");
        var elYear = document.getElementById("tbDatePickerYear");
        var d = 0;
        var m = 0;
        var yyyy = 0;
        if (elDate.value == "0" || elMonth.value == "0" || elYear.value == "0") {
            return dtTest == null && elDate.value == "0" && elMonth.value == "0" && elYear.value == "0";
        } else {
            d = this.Gcoop.ParseInt(elDate.value);
            m = this.Gcoop.ParseInt(elMonth.value) - 1;
            yyyy = this.Gcoop.ParseInt(elYear.value) - 543;
        }
        if (dtTest == null) return false;
        var theDate = this.VerifyDate(yyyy, m, d, false);
        return dtTest.getFullYear() == theDate.getFullYear() && dtTest.getMonth() == theDate.getMonth() && dtTest.getDate() == theDate.getDate();
    }

    this.SubmitDatePicker = function (dtDate) {
        if (dtDate == null) {
            if (this.dataColumnTh == "") {
                this.dataObject.SetItem(this.dataRow, this.dataColumn, "0000-00-00");
            } else {
                this.dataObject.SetItem(this.dataRow, this.dataColumnTh, "00000000");
                this.dataObject.SetItem(this.dataRow, this.dataColumn, null);
            }
            var theCallBack = this.callbackFunction;
            this.Cancel();
            if (theCallBack != null) {
                theCallBack();
            }
            return;
        }
        var d = dtDate.getDate();
        var m = dtDate.getMonth() + 1;
        var yyyy = dtDate.getFullYear();
        var mm = (m < 10 ? "0" : "") + m;
        var dd = (d < 10 ? "0" : "") + d;
        var yyth = yyyy + 543;
        if (this.dataColumnTh == "") {
            this.dataObject.SetItem(this.dataRow, this.dataColumn, yyyy + "-" + mm + "-" + dd);
        } else {
            this.dataObject.SetItem(this.dataRow, this.dataColumnTh, dd + mm + yyth);
            this.dataObject.SetItem(this.dataRow, this.dataColumn, dtDate);
        }
        var theCallBack = this.callbackFunction;
        this.Cancel();
        if (theCallBack != null) {
            theCallBack();
        }
    }

    this.OnClickDivDateRunning = function (el) {
        try {
            var inText = this.Gcoop.Trim(el.innerHTML);
            if (inText == "") {
                return;
            }
            var d = this.Gcoop.ParseInt(inText);
            var elDate = document.getElementById("tbDatePickerDay");
            var elMonth = document.getElementById("tbDatePickerMonth");
            var elYear = document.getElementById("tbDatePickerYear");
            var m = 0;
            var yyyy = 0;
            if (elDate.value == "0" || elMonth.value == "0" || elYear.value == "0") {
                var dtToday = new Date();
                m = dtToday.getMonth();
                yyyy = dtToday.getFullYear();
            } else {
                m = this.Gcoop.ParseInt(elMonth.value) - 1;
                yyyy = this.Gcoop.ParseInt(elYear.value) - 543;
            }
            var theDate = this.VerifyDate(yyyy, m, d, false);
            if (this.IsEqualTextBox(theDate)) {
                this.SubmitDatePicker(theDate);
            } else {
                this.PerformCarlendar(theDate);
            }
        } catch (err) { }
    }

    this.OnClickDivMonthBack = function () {
        var elDate = document.getElementById("tbDatePickerDay");
        var elMonth = document.getElementById("tbDatePickerMonth");
        var elYear = document.getElementById("tbDatePickerYear");
        var d = 0;
        var m = 0;
        var yyyy = 0;
        if (elDate.value == "0" || elMonth.value == "0" || elYear.value == "0") {
            var dtToday = new Date();
            d = dtToday.getDate();
            m = dtToday.getMonth();
            yyyy = dtToday.getFullYear();
        } else {
            d = this.Gcoop.ParseInt(elDate.value);
            m = this.Gcoop.ParseInt(elMonth.value) - 1;
            yyyy = this.Gcoop.ParseInt(elYear.value) - 543;
        }
        m--;
        if (m < 0) {
            m = 11
            yyyy--;
        }
        var theDate = this.VerifyDate(yyyy, m, d, false);
        this.PerformCarlendar(theDate);
    }

    this.OnClickDivMonthNext = function () {
        var elDate = document.getElementById("tbDatePickerDay");
        var elMonth = document.getElementById("tbDatePickerMonth");
        var elYear = document.getElementById("tbDatePickerYear");
        var d = 0;
        var m = 0;
        var yyyy = 0;
        if (elDate.value == "0" || elMonth.value == "0" || elYear.value == "0") {
            var dtToday = new Date();
            d = dtToday.getDate();
            m = dtToday.getMonth();
            yyyy = dtToday.getFullYear();
        } else {
            d = this.Gcoop.ParseInt(elDate.value);
            m = this.Gcoop.ParseInt(elMonth.value) - 1;
            yyyy = this.Gcoop.ParseInt(elYear.value) - 543;
        }
        m++;
        if (m > 11) {
            m = 0
            yyyy++;
        }
        var theDate = this.VerifyDate(yyyy, m, d, false);
        this.PerformCarlendar(theDate);
    }

    this.OnClickDivYearBack = function () {
        var elDate = document.getElementById("tbDatePickerDay");
        var elMonth = document.getElementById("tbDatePickerMonth");
        var elYear = document.getElementById("tbDatePickerYear");
        var d = 0;
        var m = 0;
        var yyyy = 0;
        if (elDate.value == "0" || elMonth.value == "0" || elYear.value == "0") {
            var dtToday = new Date();
            d = dtToday.getDate();
            m = dtToday.getMonth();
            yyyy = dtToday.getFullYear();
        } else {
            d = this.Gcoop.ParseInt(elDate.value);
            m = this.Gcoop.ParseInt(elMonth.value) - 1;
            yyyy = this.Gcoop.ParseInt(elYear.value) - 543;
        }
        yyyy--;
        var theDate = this.VerifyDate(yyyy, m, d, false);
        this.PerformCarlendar(theDate);
    }

    this.OnClickDivYearNext = function () {
        var elDate = document.getElementById("tbDatePickerDay");
        var elMonth = document.getElementById("tbDatePickerMonth");
        var elYear = document.getElementById("tbDatePickerYear");
        var d = 0;
        var m = 0;
        var yyyy = 0;
        if (elDate.value == "0" || elMonth.value == "0" || elYear.value == "0") {
            var dtToday = new Date();
            d = dtToday.getDate();
            m = dtToday.getMonth();
            yyyy = dtToday.getFullYear();
        } else {
            d = this.Gcoop.ParseInt(elDate.value);
            m = this.Gcoop.ParseInt(elMonth.value) - 1;
            yyyy = this.Gcoop.ParseInt(elYear.value) - 543;
        }
        yyyy++;
        var theDate = this.VerifyDate(yyyy, m, d, false);
        this.PerformCarlendar(theDate);
    }

    this.OnDdPickDayChanged = function (el) {
        var elDate = document.getElementById("tbDatePickerDay");
        var elMonth = document.getElementById("tbDatePickerMonth");
        var elYear = document.getElementById("tbDatePickerYear");
        var d = this.Gcoop.ParseInt(el.value);
        var m = 0;
        var yyyy = 0;
        if (elMonth.value == "0" || elYear.value == "0") {
            var dtToday = new Date();
            m = dtToday.getMonth();
            yyyy = dtToday.getFullYear();
        } else {
            m = this.Gcoop.ParseInt(elMonth.value) - 1;
            yyyy = this.Gcoop.ParseInt(elYear.value) - 543;
        }
        var theDate = this.VerifyDate(yyyy, m, d, true);
        this.PerformCarlendar(theDate);
    }

    this.OnDdPickMonthChanged = function (el) {
        var elDate = document.getElementById("tbDatePickerDay");
        var elMonth = document.getElementById("tbDatePickerMonth");
        var elYear = document.getElementById("tbDatePickerYear");
        var d = 0;
        var m = this.Gcoop.ParseInt(el.value) - 1;
        var yyyy = 0;
        if (elDate.value == "0" || elYear.value == "0") {
            var dtToday = new Date();
            d = dtToday.getDate();
            yyyy = dtToday.getFullYear();
        } else {
            d = this.Gcoop.ParseInt(elDate.value);
            yyyy = this.Gcoop.ParseInt(elYear.value) - 543;
        }
        var theDate = this.VerifyDate(yyyy, m, d, false);
        this.PerformCarlendar(theDate);
    }

    this.OnDdPickYearChanged = function (el) {
        var elDate = document.getElementById("tbDatePickerDay");
        var elMonth = document.getElementById("tbDatePickerMonth");
        var elYear = document.getElementById("tbDatePickerYear");
        var d = 0;
        var m = 0;
        var yyyy = this.Gcoop.ParseInt(el.value) - 543;
        if (elDate.value == "0" || elMonth.value == "0") {
            var dtToday = new Date();
            d = dtToday.getDate();
            m = dtToday.getMonth();
        } else {
            d = this.Gcoop.ParseInt(elDate.value);
            m = this.Gcoop.ParseInt(elMonth.value) - 1;
        }
        var theDate = this.VerifyDate(yyyy, m, d, false);
        this.PerformCarlendar(theDate);
    }

    this.OnClickNullButton = function () {
        if (this.IsEqualTextBox(null)) {
            this.SubmitDatePicker(null);
        } else {
            this.PerformCarlendar(null);
        }
    }

    this.OnClickToDayButton = function () {
        if (this.IsEqualTextBox(new Date())) {
            this.SubmitDatePicker(new Date());
        } else {
            this.PerformCarlendar(new Date());
        }
    }

    this.OnClickSubmitButton = function () {
        var elDate = document.getElementById("tbDatePickerDay");
        var elMonth = document.getElementById("tbDatePickerMonth");
        var elYear = document.getElementById("tbDatePickerYear");
        var d = 0;
        var m = 0;
        var yyyy = 0;
        if (elDate.value == "0" || elMonth.value == "0" || elYear.value == "0") {
            this.SubmitDatePicker(null);
        } else {
            d = this.Gcoop.ParseInt(elDate.value);
            m = this.Gcoop.ParseInt(elMonth.value) - 1;
            yyyy = this.Gcoop.ParseInt(elYear.value) - 543;
            var theDate = this.VerifyDate(yyyy, m, d, false);
            this.SubmitDatePicker(theDate);
        }
    }
}