// ==UserScript==
// @name         ShalaDarpan Attendance Auto Fill (Safe & Dynamic)
// @namespace    https://rajshaladarpan.rajasthan.gov.in/
// @version      2.2
// @description  Auto-fill attendance only when attendance table exists (all schools)
// @match        https://rajshaladarpan.rajasthan.gov.in/*/Home/School/StudentAttendence.aspx
// @grant        none
// ==/UserScript==

(function () {
    'use strict';

    /**************** FLOATING BUTTON ****************/
    const btn = document.createElement('button');
    btn.innerText = '⚡ Auto Fill Attendance';

    Object.assign(btn.style, {
        position: 'fixed',
        bottom: '20px',
        right: '20px',
        zIndex: '99999',
        padding: '12px 16px',
        backgroundColor: '#28a745',
        color: '#fff',
        border: 'none',
        borderRadius: '6px',
        cursor: 'pointer',
        fontSize: '14px',
        boxShadow: '0 3px 8px rgba(0,0,0,0.3)'
    });

    document.body.appendChild(btn);

    /**************** HELPERS ****************/

    function getSchoolCode() {
        const lbl = document.getElementById('lblSchcd');
        if (!lbl) return null;

        const span = lbl.querySelector('span');
        return span ? span.innerText.trim() : null;
    }

    function getSelectText(id) {
        const el = document.getElementById(id);
        return el ? el.options[el.selectedIndex]?.text.trim() : '';
    }

    function monthShort(monthText) {
        const map = {
            January: 'Jan',
            February: 'Feb',
            March: 'Mar',
            April: 'Apr',
            May: 'May',
            June: 'Jun',
            July: 'Jul',
            August: 'Aug',
            September: 'Sep',
            October: 'Oct',
            November: 'Nov',
            December: 'Dec'
        };
        return map[monthText] || monthText;
    }

    function attendanceTableExists() {
        return document.getElementById('ContentPlaceHolder1_footer2_gvattendence');
    }

    /**************** MAIN LOGIC ****************/

    btn.addEventListener('click', async () => {

        // ✅ Check table existence FIRST
        if (!attendanceTableExists()) {
            alert('❌ Attendance table not loaded.\nPlease select Class, Section & Month and wait.');
            return;
        }

        const schoolCode = getSchoolCode();
        if (!schoolCode) {
            alert('❌ School Code (NIC-SD ID) not found');
            return;
        }

        const classVal = getSelectText('ContentPlaceHolder1_footer2_ddlclass');
        const sectionVal = getSelectText('ContentPlaceHolder1_footer2_ddlsection');
        const monthText = getSelectText('ContentPlaceHolder1_footer2_ddlmonth');
        const monthVal = monthShort(monthText);

        if (!classVal || !sectionVal || !monthVal) {
            alert('❌ Please select Class, Section and Month');
            return;
        }

        const apiUrl =
            `https://sd.rankguruji.com/api/load_students.php` +
            `?code=${schoolCode}&class=${classVal}&section=${sectionVal}&month=${monthVal}`;

        console.log('📡 Fetching:', apiUrl);

        try {
            const res = await fetch(apiUrl);
            const data = await res.json();

            if (!data.students || !data.students.length) {
                alert('❌ No student data found from API');
                return;
            }

            // Build SRNO → Days map
            const studentMap = {};
            data.students.forEach(s => {
                studentMap[s.srno] = s.days;
            });

            // Fill attendance
            let index = 0;
            let filled = 0;

            while (true) {
                const srnoSpan = document.getElementById(
                    `ContentPlaceHolder1_footer2_gvattendence_lblsrno_${index}`
                );
                const input = document.getElementById(
                    `ContentPlaceHolder1_footer2_gvattendence_txtatt_${index}`
                );

                if (!srnoSpan || !input) break;

                const srno = srnoSpan.innerText.trim();

                if (studentMap[srno] !== undefined) {
                    input.value = studentMap[srno];
                    input.style.backgroundColor = '#d4edda';
                    filled++;
                } else {
                    input.style.backgroundColor = '#f8d7da';
                }

                index++;
            }

            alert(`✅ Attendance auto-filled for ${filled} students`);

        } catch (err) {
            console.error('❌ Error:', err);
            alert('❌ Failed to load attendance data');
        }
    });

})();