let data = {};
let showAllMatches = false;
let viewingNextSeason = false;
let initialLoad = true;

function parseDate(str) {
    const [d, m, y] = str.split('/').map(Number);
    return new Date(2000 + y, m - 1, d);
}

function getSeasonYear(dateStr) {
    const [d, m, y] = dateStr.split('/').map(Number);
    return m >= 4 ? 2000 + y : 1999 + y;
}

function currentSeasonYear() {
    const now = new Date();
    const m = now.getMonth() + 1;
    return m >= 4 ? now.getFullYear() : now.getFullYear() - 1;
}

function fetchData() {
    fetch('/api/data').then(r => r.json()).then(d => {
        data = d;
        updateSeasonButton();
        renderTable();
    });
}

function updateSeasonButton() {
    const thisSeason = currentSeasonYear();
    const hasNextSeason = (data.dates || []).some(d => getSeasonYear(d) === thisSeason + 1);
    const btn = document.getElementById('next-season-btn');
    if (btn) btn.style.display = hasNextSeason ? '' : 'none';
}

function saveData() {
    fetch('/api/data', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(data)
    });
}

function renderTable() {
    const container = document.getElementById('attendance-table');
    const scrollTop = window.scrollY;
    container.innerHTML = '';
    const table = document.createElement('table');

    // Header row
    const thead = document.createElement('thead');
    const headRow = document.createElement('tr');
    const dateTh = document.createElement('th');
    dateTh.innerText = 'Date';
    dateTh.style.width = '120px';
    dateTh.style.minWidth = '100px';
    dateTh.style.maxWidth = '140px';
    dateTh.style.textAlign = 'left';
    headRow.appendChild(dateTh);
    data.players.forEach(name => {
        const th = document.createElement('th');
        th.innerText = name;
        th.classList.add('name-col');
        headRow.appendChild(th);
    });
    const guestNameTh = document.createElement('th');
    guestNameTh.innerText = 'Guest Name';
    guestNameTh.classList.add('name-col');
    headRow.appendChild(guestNameTh);
    thead.appendChild(headRow);
    table.appendChild(thead);

    // Body rows
    const tbody = document.createElement('tbody');
    if (!data.guestNames) data.guestNames = {};

    const today = new Date();
    const thisSeason = currentSeasonYear();
    const targetSeason = viewingNextSeason ? thisSeason + 1 : thisSeason;

    let filteredDates = (data.dates || []).filter(d => getSeasonYear(d) === targetSeason);
    if (!viewingNextSeason && !showAllMatches) {
        filteredDates = filteredDates.filter(date => parseDate(date) > today);
    }

    // Find closest date for auto-scroll
    let closestIdx = 0;
    let minDiff = Infinity;
    filteredDates.forEach((date, rowIdx) => {
        const diff = Math.abs(parseDate(date) - today);
        if (diff < minDiff) { minDiff = diff; closestIdx = rowIdx; }
    });

    filteredDates.forEach((date, rowIdx) => {
        const tr = document.createElement('tr');
        if (rowIdx === closestIdx) tr.id = 'current-match-row';

        // Date cell
        const dateTd = document.createElement('td');
        dateTd.style.width = '120px';
        dateTd.style.minWidth = '100px';
        dateTd.style.maxWidth = '140px';
        dateTd.style.textAlign = 'left';
        if (date === '29/05/25' || date === '25/12/25' || date === '01/01/26') {
            const strong = document.createElement('strong');
            strong.innerText = date;
            dateTd.appendChild(strong);
            dateTd.title = 'Public Holiday';
        } else {
            dateTd.innerText = date;
        }
        tr.appendChild(dateTd);

        // Player attendance cells
        data.players.forEach((player, colIdx) => {
            const td = document.createElement('td');
            const key = `${date}|${colIdx}`;

            const setCell = val => {
                if (val === true) {
                    td.innerText = 'Yes'; td.className = 'clickable name-col yes';
                } else if (val === 'no') {
                    td.innerText = 'No'; td.className = 'clickable name-col no';
                } else if (val === 'maybe') {
                    td.innerText = 'Maybe'; td.className = 'clickable name-col maybe';
                } else {
                    td.innerText = ''; td.className = 'clickable name-col';
                }
            };
            setCell(data.attendance[key]);

            td.onclick = () => {
                const cur = data.attendance[key];
                if (!cur) data.attendance[key] = true;
                else if (cur === true) data.attendance[key] = 'no';
                else if (cur === 'no') data.attendance[key] = 'maybe';
                else delete data.attendance[key];
                setCell(data.attendance[key]);
                saveData();
            };
            tr.appendChild(td);
        });

        // Guest Name column
        const guestNameTd = document.createElement('td');
        guestNameTd.classList.add('name-col');
        const guestNameInput = document.createElement('input');
        guestNameInput.type = 'text';
        guestNameInput.value = data.guestNames[date] || '';
        guestNameInput.placeholder = 'Enter guest name';
        guestNameInput.maxLength = 50;
        guestNameInput.onchange = e => {
            let value = e.target.value;
            if (value === '') {
                delete data.guestNames[date];
                saveData();
                return;
            }
            if (/</.test(value) || />/.test(value) || /["'`\\]/.test(value)) {
                alert('Guest name cannot contain special characters like <, >, ", \\, or backticks.');
                guestNameInput.value = data.guestNames[date] || '';
                return;
            }
            if (!/^([a-zA-Z0-9 .-]+)$/.test(value)) {
                alert('Guest name can only contain letters, numbers, spaces, hyphens, and periods.');
                guestNameInput.value = data.guestNames[date] || '';
                return;
            }
            if (value.length > 50) {
                value = value.slice(0, 50);
                guestNameInput.value = value;
            }
            data.guestNames[date] = value;
            saveData();
        };
        guestNameTd.appendChild(guestNameInput);
        tr.appendChild(guestNameTd);
        tbody.appendChild(tr);
    });

    table.appendChild(tbody);
    container.appendChild(table);

    setTimeout(() => {
        if (initialLoad) {
            const row = document.getElementById('current-match-row');
            if (row) row.scrollIntoView({ behavior: 'smooth', block: 'center' });
            initialLoad = false;
        } else {
            window.scrollTo({ top: scrollTop });
        }
    }, 0);
}

document.addEventListener('DOMContentLoaded', () => {
    fetchData();

    const toggleBtn = document.getElementById('toggle-matches-btn');
    if (toggleBtn) {
        toggleBtn.textContent = 'Show All Matches';
        toggleBtn.onclick = () => {
            showAllMatches = !showAllMatches;
            toggleBtn.textContent = showAllMatches ? 'Show Future Matches' : 'Show All Matches';
            renderTable();
        };
    }

    const nextSeasonBtn = document.getElementById('next-season-btn');
    if (nextSeasonBtn) {
        nextSeasonBtn.onclick = () => {
            viewingNextSeason = !viewingNextSeason;
            nextSeasonBtn.textContent = viewingNextSeason ? 'Current Season' : 'Next Season';
            // Reset "show all" toggle when switching seasons
            showAllMatches = false;
            if (toggleBtn) toggleBtn.textContent = 'Show All Matches';
            initialLoad = true;
            renderTable();
        };
    }
});