// Alchemy Potion Sliding Block Puzzle (Schieberätsel)
(function() {
    const gridEl = document.getElementById('slidingGrid');
    if (!gridEl) return;

    const movesVal = document.getElementById('slidingMoves');
    const timerVal = document.getElementById('slidingTimer');
    const modalBackdrop = document.getElementById('modalBackdrop');
    const modalTitle = document.getElementById('modalTitle');
    const modalText = document.getElementById('modalText');
    const modalBtn = document.getElementById('modalBtn');
    const btnScramble = document.getElementById('btnScramble');

    const SIZE = 3; // 3x3 sliding puzzle (8 tiles + 1 blank)
    let tiles = [];
    let blankIndex = 8;
    let moves = 0;
    let timerInterval = null;
    let secondsElapsed = 0;
    let isSolved = false;

    // Tile images / potion runes
    const tileSymbols = [
        { id: 1, icon: "🧪", name: "Alraune", color: "#2ecc71" },
        { id: 2, icon: "🍷", name: "Brennnesselwein", color: "#e74c3c" },
        { id: 3, icon: "⚡", name: "Blitzphiole", color: "#f1c40f" },
        { id: 4, icon: "🔮", name: "Phönix-Träne", color: "#9b59b6" },
        { id: 5, icon: "🐉", name: "Drachenblut", color: "#e67e22" },
        { id: 6, icon: "💀", name: "Tobsuchtsgift", color: "#1abc9c" },
        { id: 7, icon: "💎", name: "Elixier des Lebens", color: "#3498db" },
        { id: 8, icon: "🕯️", name: "Ewige Flamme", color: "#d35400" },
        { id: 0, icon: "", name: "Leerer Runen-Sockel", color: "transparent" } // Blank
    ];

    function init() {
        tiles = [1, 2, 3, 4, 5, 6, 7, 8, 0];
        blankIndex = 8;
        moves = 0;
        secondsElapsed = 0;
        isSolved = false;
        if (movesVal) movesVal.innerText = moves;
        if (timerVal) timerVal.innerText = '0s';
        if (timerInterval) clearInterval(timerInterval);
        timerInterval = setInterval(() => {
            if (!isSolved) {
                secondsElapsed++;
                if (timerVal) timerVal.innerText = secondsElapsed + 's';
            }
        }, 1000);

        scramble();
        render();
    }

    function scramble() {
        // Perform 60 random valid moves from blank to ensure solvability
        for (let i = 0; i < 60; i++) {
            const neighbors = getNeighbors(blankIndex);
            const randomNeighbor = neighbors[Math.floor(Math.random() * neighbors.length)];
            tiles[blankIndex] = tiles[randomNeighbor];
            tiles[randomNeighbor] = 0;
            blankIndex = randomNeighbor;
        }
        moves = 0;
        if (movesVal) movesVal.innerText = moves;
    }

    function getNeighbors(idx) {
        const row = Math.floor(idx / SIZE);
        const col = idx % SIZE;
        const res = [];
        if (row > 0) res.push(idx - SIZE); // Up
        if (row < SIZE - 1) res.push(idx + SIZE); // Down
        if (col > 0) res.push(idx - 1); // Left
        if (col < SIZE - 1) res.push(idx + 1); // Right
        return res;
    }

    function render() {
        gridEl.innerHTML = '';
        tiles.forEach((val, idx) => {
            const tile = document.createElement('div');
            tile.className = 'sliding-tile' + (val === 0 ? ' blank' : '');
            tile.dataset.index = idx;

            if (val !== 0) {
                const info = tileSymbols.find(s => s.id === val);
                tile.innerHTML = `
                    <span class="tile-icon">${info.icon}</span>
                    <span class="tile-num">${val}</span>
                    <span class="tile-name">${info.name}</span>
                `;
                tile.style.borderColor = info.color;
            }

            tile.addEventListener('click', () => onTileClick(idx));
            gridEl.appendChild(tile);
        });
    }

    function onTileClick(idx) {
        if (isSolved) return;
        const neighbors = getNeighbors(idx);
        if (neighbors.includes(blankIndex)) {
            // Swap with blank
            tiles[blankIndex] = tiles[idx];
            tiles[idx] = 0;
            blankIndex = idx;
            moves++;
            if (movesVal) movesVal.innerText = moves;

            if (window.soundFX) window.soundFX.playStoneSlide();
            render();
            checkWin();
        }
    }

    function checkWin() {
        const winning = [1, 2, 3, 4, 5, 6, 7, 8, 0];
        const match = tiles.every((v, i) => v === winning[i]);
        if (match) {
            isSolved = true;
            clearInterval(timerInterval);
            if (window.soundFX) window.soundFX.playMagicSuccess();

            fetch('/api/sliding/complete', { method: 'POST' }).catch(console.error);

            modalTitle.innerText = "✨ Schieberätsel gelöst!";
            modalText.innerHTML = `Mit geschicktem Schieben hast du alle 8 alchemistischen Phiolen in die perfekte harmonische Ordnung gebracht!<br><br>
            <strong>Züge:</strong> ${moves}<br>
            <strong>Zeit:</strong> ${secondsElapsed} Sekunden<br><br>
            Die Runenplatte leuchtet golden auf und der Weg zur Flammenkammer öffnet sich!`;
            modalBtn.innerText = "Zur Flammenkammer 🧪";
            modalBtn.onclick = () => { window.location.href = '/bottles'; };
            modalBackdrop.classList.add('show');
        }
    }

    if (btnScramble) {
        btnScramble.addEventListener('click', () => {
            if (window.soundFX) window.soundFX.playStoneSlide();
            init();
        });
    }

    init();
})();