const canvas    = document.getElementById('gameCanvas');
const ctx       = canvas.getContext('2d');
const cysCanvas = document.getElementById('cystinstein-canvas');
const cysCtx    = cysCanvas.getContext('2d');

canvas.width  = window.innerWidth;
canvas.height = window.innerHeight;

const CX = canvas.width  / 2;
const CY = canvas.height / 2;

// ─── Leaderboard ─────────────────────────────────────────────────────────────
const LEADERBOARD_KEY    = 'sysdigger_leaderboard';
const LEADERBOARD_MAX    = 10;

function loadLeaderboard() {
    try {
        return JSON.parse(localStorage.getItem(LEADERBOARD_KEY)) || [];
    } catch {
        return [];
    }
}

function saveLeaderboard(board) {
    localStorage.setItem(LEADERBOARD_KEY, JSON.stringify(board));
}

function addEntry(name, score) {
    const board = loadLeaderboard();
    board.push({ name: name.trim() || 'Anonymous', score });
    board.sort((a, b) => b.score - a.score);
    const trimmed = board.slice(0, LEADERBOARD_MAX);
    saveLeaderboard(trimmed);
    return trimmed;
}

function renderLeaderboard(highlightEntry) {
    const board = loadLeaderboard();
    const tbody = document.getElementById('leaderboard-rows');
    tbody.innerHTML = '';

    if (board.length === 0) {
        const tr = document.createElement('tr');
        tr.innerHTML = `<td colspan="3" style="color:#555;text-align:center;padding:12px">No scores yet</td>`;
        tbody.appendChild(tr);
        return;
    }

    board.forEach((entry, i) => {
        const tr = document.createElement('tr');
        const isHighlight = highlightEntry &&
            entry.name  === highlightEntry.name &&
            entry.score === highlightEntry.score;

        if (isHighlight) tr.classList.add('highlight');
        else if (i === 0) tr.classList.add('rank-1');
        else if (i === 1) tr.classList.add('rank-2');
        else if (i === 2) tr.classList.add('rank-3');

        const medal = i === 0 ? '🥇' : i === 1 ? '🥈' : i === 2 ? '🥉' : i + 1;
        tr.innerHTML = `
            <td class="rank-num">${medal}</td>
            <td style="text-align:left">${escapeHtml(entry.name)}</td>
            <td style="text-align:right">${entry.score}</td>`;
        tbody.appendChild(tr);
    });
}

function escapeHtml(str) {
    return str.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;');
}

function topScore() {
    const board = loadLeaderboard();
    return board.length > 0 ? board[0].score : null;
}

// ─── State ───────────────────────────────────────────────────────────────────
let score         = 0;
let docks         = 0;
let gameOver      = false;
let gameStarted   = false;
let incomingAtoms = [];
let anchorPoints  = [];
let particles     = [];
let clickEffects  = [];
let lastSpawn     = 0;
let spawnInterval = SPAWN_INTERVAL_START;

const stars = Array.from({ length: STAR_COUNT }, () => ({
    x: Math.random() * canvas.width,
    y: Math.random() * canvas.height,
    r: Math.random() * STAR_RADIUS_MAX,
    a: STAR_ALPHA_MIN + Math.random() * STAR_ALPHA_RANGE
}));

// ─── Anchors ─────────────────────────────────────────────────────────────────
function initAnchors() {
    anchorPoints = [];
    for (let i = 0; i < NUM_ANCHORS; i++) {
        const angle = (i / NUM_ANCHORS) * Math.PI * 2 - Math.PI / 2;
        anchorPoints.push({
            x: CX + Math.cos(angle) * ANCHOR_RADIUS,
            y: CY + Math.sin(angle) * ANCHOR_RADIUS,
            angle,
            active: false,
            blockTimer: 0,
            pulsePhase: Math.random() * Math.PI * 2
        });
    }
}

// ─── Spawn ───────────────────────────────────────────────────────────────────
function spawnAtom() {
    const available = anchorPoints.map((_, i) => i).filter(i => !anchorPoints[i].active);
    if (available.length === 0) return;
    const idx = available[Math.floor(Math.random() * available.length)];
    incomingAtoms.push(new IncomingAtom(idx));
}

// ─── Input ───────────────────────────────────────────────────────────────────
canvas.addEventListener('click', e => {
    if (gameOver) return;
    const rect = canvas.getBoundingClientRect();
    const mx   = e.clientX - rect.left;
    const my   = e.clientY - rect.top;
    let hit    = false;

    anchorPoints.forEach((ap, i) => {
        if (!ap.active) return;
        if (Math.hypot(mx - ap.x, my - ap.y) > CLICK_RADIUS) return;

        const atom = incomingAtoms.find(a => a.anchorIndex === i && !a.dead);
        if (atom) {
            atom.dead     = true;
            ap.active     = false;
            ap.blockTimer = BLOCK_TIMER_FRAMES;
            score++;
            document.getElementById('score').textContent = `Score: ${score}`;
            burst(ap.x, ap.y, '#00ff88');
            clickEffects.push({ x: ap.x, y: ap.y, radius: 5, life: 1 });
            hit = true;
        }
    });

    if (!hit) clickEffects.push({ x: mx, y: my, radius: 5, life: 0.5 });
});

// ─── Game flow ───────────────────────────────────────────────────────────────
function triggerGameOver() {
    gameOver = true;
    const best        = topScore();
    const isNewRecord = best === null || score > best;

    document.getElementById('final-score').textContent = `Score: ${score}`;
    document.getElementById('new-record').classList.toggle('visible', isNewRecord);

    const input = document.getElementById('player-name');
    input.value = '';
    setTimeout(() => input.focus(), 50);

    renderLeaderboard(null);
    document.getElementById('overlay').classList.add('active');
}

function submitScore() {
    const name  = document.getElementById('player-name').value.trim() || 'Anonymous';
    const entry = { name, score };
    addEntry(name, score);
    renderLeaderboard(entry);

    const best = topScore();
    updateHudBest(best);

    document.getElementById('name-form').style.display = 'none';
}

function restartGame() {
    score = docks = 0;
    gameOver      = false;
    gameStarted   = false;
    incomingAtoms = [];
    particles     = [];
    clickEffects  = [];
    lastSpawn     = 0;
    spawnInterval = SPAWN_INTERVAL_START;
    document.getElementById('score').textContent       = 'Score: 0';
    document.getElementById('docks-count').textContent = `0 / ${MAX_DOCKS} docks`;
    document.getElementById('name-form').style.display = 'flex';
    document.getElementById('overlay').classList.remove('active');
    document.getElementById('intro').classList.remove('hidden');
    startIdleTimer();
    initAnchors();
    updateCystinstein();
}

// ─── Attract mode ────────────────────────────────────────────────────────────
const ATTRACT_DELAY = 30_000;
let idleTimer = null;

function startIdleTimer() {
    clearTimeout(idleTimer);
    idleTimer = setTimeout(showAttract, ATTRACT_DELAY);
}

function showAttract() {
    document.getElementById('intro').classList.add('hidden');
    renderAttractLeaderboard();
    document.getElementById('attract').classList.remove('hidden');
}

function showIntro() {
    document.getElementById('attract').classList.add('hidden');
    document.getElementById('intro').classList.remove('hidden');
    startIdleTimer();
}

function renderAttractLeaderboard() {
    const board = loadLeaderboard();
    const tbody = document.getElementById('attract-rows');
    tbody.innerHTML = '';

    if (board.length === 0) {
        tbody.innerHTML = `<tr><td colspan="3" style="color:#555;text-align:center;padding:16px">No scores yet — be the first!</td></tr>`;
        return;
    }

    board.forEach((entry, i) => {
        const tr = document.createElement('tr');
        if      (i === 0) tr.classList.add('rank-1');
        else if (i === 1) tr.classList.add('rank-2');
        else if (i === 2) tr.classList.add('rank-3');
        const medal = i === 0 ? '🥇' : i === 1 ? '🥈' : i === 2 ? '🥉' : i + 1;
        tr.innerHTML = `
            <td class="rank-num">${medal}</td>
            <td style="text-align:left">${escapeHtml(entry.name)}</td>
            <td style="text-align:right">${entry.score}</td>`;
        tbody.appendChild(tr);
    });
}

function dismissAttract() {
    if (!document.getElementById('attract').classList.contains('hidden')) {
        showIntro();
    }
}

document.addEventListener('keydown', dismissAttract);
document.addEventListener('click',   dismissAttract);

function startGame() {
    clearTimeout(idleTimer);
    gameStarted = true;
    document.getElementById('intro').classList.add('hidden');
}

function updateHudBest(best) {
    document.getElementById('highscore').textContent = best !== null ? `Best: ${best}` : 'Best: —';
}

// ─── Enter key on name input ──────────────────────────────────────────────────
document.getElementById('player-name').addEventListener('keydown', e => {
    if (e.key === 'Enter') submitScore();
});

// ─── Main loop ───────────────────────────────────────────────────────────────
function gameLoop(ts) {
    drawBackground();

    if (gameStarted && !gameOver && ts - lastSpawn > spawnInterval) {
        spawnAtom();
        lastSpawn     = ts;
        spawnInterval = Math.max(SPAWN_INTERVAL_MIN, spawnInterval - SPAWN_DIFFICULTY_STEP);
    }

    incomingAtoms = incomingAtoms.filter(a => !a.dead);
    incomingAtoms.forEach(a => { a.update(); a.draw(); });

    drawCentralMolecule();
    drawAnchorPoints();
    drawParticles();
    drawClickEffects();

    requestAnimationFrame(gameLoop);
}

// ─── Boot ────────────────────────────────────────────────────────────────────
document.getElementById('intro').innerHTML =
    document.getElementById('intro').innerHTML.replace('${MAX_DOCKS}', MAX_DOCKS);
updateHudBest(topScore());
startIdleTimer();
initAnchors();
updateCystinstein();
requestAnimationFrame(gameLoop);