av_table

const d = new Date(); // d is a date of today. example: 30-09-2019
let month = d.getMonth(); // month is a month of today example: var month for september : 9
let year = d.getFullYear(); // year is a year of today
const months = ["January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"];
const days = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"];

export const nextAndPreviousTable = document.getElementById("nextPreviousMonth");
export const firstRow = nextAndPreviousTable.querySelectorAll("tbody tr:first-child")[0];
const currentMonthAndYear = firstRow.querySelectorAll("td:first-child span:first-of-type")[0];
currentMonthAndYear.innerHTML = months[month] + " " + year;
const tableArea = document.getElementById("tableArea");
export function start() {
    createTable2(month, year);
}

export function next() {
    deleteTable2(month, year);
    if (month >= months.length) {
        year = year + 1;
        month = month - 12;
        currentMonthAndYear.innerHTML = months[month] + " " + year;
        createTable2(month, year);
    }
    if (month < months.length) {
        month = month + 1;
        if (month >= months.length) {
            year = year + 1;
            month = month - 12;
            currentMonthAndYear.innerHTML = months[month] + " " + year;
            createTable2(month, year);
        } else {
            currentMonthAndYear.innerHTML = months[month] + " " + year;
            createTable2(month, year);
        }
    }

}

export function previous() {
    deleteTable2(month, year)
    if (month <= 0) {
        month = month + 12;
        year = year - 1;
        currentMonthAndYear.innerHTML = months[month] + " " + year;
        createTable2(month, year);
    }
    if (month > 0) {
        month = month - 1;
        if (month < 0) {
            month = month + 12;
            year = year - 1;
            currentMonthAndYear.innerHTML = months[month] + " " + year;
            createTable2(month, year);
        } else {
            currentMonthAndYear.innerHTML = months[month] + " " + year;
            createTable2(month, year);
        }
    }
}

/*
createTable2() create a table
*/

function createTable2(month, year) {

    if (month == 0 || month == 2 || month == 4 || month == 6 || month == 7 || month == 9 || month == 11) {
        for (let day = 1; day <= 31; day++) {
            createTheRowForTable2(day, month, year);
        }
        // create a table for months with 31 days
    }
    if (month == 3 || month == 5 || month == 8 || month == 10) {
        for (let day = 1; day <= 30; day++) {
            createTheRowForTable2(day, month, year);
        }
        // create a table for months with 30 days
    }
    if (month == 1 && year % 4 != 0) {
        for (let day = 1; day <= 28; day++) {
            createTheRowForTable2(day, month, year);
        }
        // create a table for february with 28 days
    }
    if (month == 1 && year % 4 == 0) {
        for (let day = 1; day <= 29; day++) {
            createTheRowForTable2(day, month, year);
        }
        // create a table for february with 29 days
    }
}

function deleteTable2(month, year) {
    if (month == 0 || month == 2 || month == 4 || month == 6 || month == 7 || month == 9 || month == 11) {
        for (let day = 1; day <= 31; day++) {
            tableArea.deleteRow(1);
        }
    }
    if (month == 3 || month == 5 || month == 8 || month == 10) {
        for (let day = 1; day <= 30; day++) {
            tableArea.deleteRow(1);
        }
    }
    if (month == 1 && year % 4 != 0) {
        for (let day = 1; day <= 28; day++) {
            tableArea.deleteRow(1);
        }
    }
    if (month == 1 && year % 4 == 0) {
        for (let day = 1; day <= 29; day++) {
            tableArea.deleteRow(1);
        }
    }
}
/*
this function create a row for the different days of a month
*/

function createTheRowForTable2(day, month, year) {

    let tr = tableArea.insertRow(day);
    tr.id = "tr";
    let td1 = tr.insertCell(0);
    td1.id = "td1";
    let td2 = tr.insertCell(1);
    td2.id = "td2";

    let td3 = tr.insertCell(2);
    td3.id = "td3";

    let fullDate = new Date(year, month, day);
    let weekDay = fullDate.getDay(); // example: weekDay=1=monday

    const checkboxForAvailability = document.createElement("table");
    checkboxForAvailability.className = "checkboxArea";
    const rowForAvailability = checkboxForAvailability.insertRow(0);
    const availabilityOptions = ["available", "not available","preferred"];
    availabilityOptions.forEach(function(option){
        let cellForAvailability = rowForAvailability.insertCell(availabilityOptions.indexOf(option));  // to find the index of availabilityOptions
        const choice = document.createElement("input");
        choice.type ="radio";
        choice.name = "availability"+day;
        choice.value = option;
        let labelForChoice = document.createElement("label");
        labelForChoice.className="container";
        labelForChoice.appendChild(choice);
        labelForChoice.appendChild(document.createTextNode(option));
        cellForAvailability.appendChild(labelForChoice);
    });

    const checkboxForShift = document.createElement("table");
    checkboxForShift.className = "checkboxArea";
    const rowForShift = checkboxForShift.insertRow(0);
    const shiftOptions = ["08:00-20:00", "20:00-08:00"];
    shiftOptions.forEach(function(option){
        let cellForShift = rowForShift.insertCell(shiftOptions.indexOf(option));
        const choice = document.createElement("input");
        choice.type ="checkbox";
        choice.name = option;
        choice.value = option;
        const labelForChoice = document.createElement("label");
        labelForChoice.className="container";
        labelForChoice.appendChild(choice);
        labelForChoice.appendChild(document.createTextNode(option));
        cellForShift.appendChild(labelForChoice);
    });

    if (calcDoubleShifts(day, month, year) == true) {
        td1.innerHTML = days[weekDay] + " " + day + " " + months[month] + " " + year;
        td2.appendChild(checkboxForAvailability);
        td3.appendChild(checkboxForShift);
    } else {
        td1.innerHTML = days[weekDay] + " " + day + " " + months[month] + " " + year;
        td2.appendChild(checkboxForAvailability);
        const singleShift = document.createTextNode(shiftOptions[1]);
        td3.appendChild(singleShift);
    }
    day++;
}
/*
this function give us the days with 2 shifts
*/
export function calcDoubleShifts(day, month, year) {
    let doubleShift = false;
    let fullDate = new Date(year, month, day);
    let weekDay = fullDate.getDay();
    let monthAndDay = (month + 1) + "-" + day;
    if (weekDay == 0 || weekDay == 6) {
        doubleShift = true;
    }

    if (monthAndDay == "1-1" || monthAndDay == "5-1" || monthAndDay == "10-3" ||
        monthAndDay == "12-25" || monthAndDay == "12-26" || monthAndDay == "11-1") {
        doubleShift = true;
    }
    let eastern = calcEastern(year);
    let easterMonth = 3;
    if (eastern > 31) {
        eastern = eastern - 31;
        easterMonth = 4;
        if (eastern <= 2) {
            if (monthAndDay == "3-" + (eastern + 29) || monthAndDay == "4-" + (eastern + 1)) {
                doubleShift = true;
            }
        } else {
            if (monthAndDay == "4-" + (eastern - 2) || monthAndDay == "4-" + (eastern + 1)) {
                doubleShift = true;
            }
        }
    } else {
        if (monthAndDay == "3-" + (eastern - 2) || monthAndDay == "3-" + (eastern + 1)) {
            doubleShift = true;
        }
    }
    /*
    let easterDate = new Date(year,easterMonth,eastern);
    easterDate.setDate(eastern+39);
    console.log(easterDate);
    */
    return doubleShift;

}
/*
calcEastern give us the day of eastern for different years
*/
export function calcEastern(year) {

    let k = year / 100;
    let m = 15 + (3 * k + 3) / 4 - (8 * k + 13) / 25;
    let s = 2 - (3 * k + 3) / 4;
    let a = year % 19;
    let d = (19 * a + m) % 30;
    let r = (d + a / 11) / 29;
    let og = 21 + d - r;
    let sz = 7 - (year + year / 4 + s) % 7;
    let oe = 7 - (og - sz) % 7;
    let dayOfEastern = og + oe;

    return Math.trunc(dayOfEastern);
}

export function sendTheChoice() {

    if (month == 0 || month == 2 || month == 4 || month == 6 || month == 7 || month == 9 || month == 11) {
        for (let day = 1; day <= 31; day++) {
            let selector = document.getElementById("selected2" + day);
            let choice = selector.options[selector.selectedIndex].value;
            if (choice == "---") {
                console.log("error");
                alert("check your answers");
            }

        }
    }
    if (month == 3 || month == 5 || month == 8 || month == 10) {
        for (let day = 1; day <= 30; day++) {

            let selector = document.getElementById("selected2" + day);
            let choice = selector.options[selector.selectedIndex].value;
            if (choice == "---") {
                console.log("error");
                alert("check your answers");
            }
        }
    }
    if (month == 1 && year % 4 != 0) {

        for (let day = 1; day <= 28; day++) {
            let selector = document.getElementById("selected2" + day);
            let choice = selector.options[selector.selectedIndex].value;
            if (choice == "---") {
                alert("check your answers");
            }
        }

    }

}