/**
 * minigames/puzzle.js
 * 🧩 Zahlen-Puzzle — Schiebe die Kacheln in die richtige Reihenfolge! (15-Puzzle)
 */
window.MG_puzzle = (function() {

  const ID       = 'puzzle';
  const EMOJI    = '🧩';
  const NAME     = 'Zahlen-Puzzle';
  const DESC     = 'Schiebe die Kacheln in die richtige Reihenfolge (1–8)!';
  const CONTROLS = 'Mausklick / Pfeiltasten';
  const MULTI    = 1;

  function run(wrap, W, H, cfg, onDone) {
    const { canvas, ctx } = MGAPI.makeCanvas(wrap, W, H);
    const theme = cfg.theme || { primary: '#14b8a6' };

    const SIZE  = 3; // 3×3
    const PAD   = 20;
    const cellW = Math.floor((W - PAD * 2) / SIZE);
    const cellH = Math.floor((H - PAD * 2 - 30) / SIZE);
    const OX    = (W - SIZE * cellW) / 2;
    const OY    = 30 + (H - 30 - SIZE * cellH) / 2;

    // Ziel: 1 2 3 / 4 5 6 / 7 8 _
    const GOAL  = [1,2,3,4,5,6,7,8,0];
    let board   = [...GOAL];
    let moves   = 0;
    let stopped = false;
    let raf, endTimer, solved = false;

    // Mischeln (100 zufällige Züge)
    function shuffle() {
      for (let i = 0; i < 100; i++) {
        const ei  = board.indexOf(0);
        const er  = Math.floor(ei / SIZE), ec = ei % SIZE;
        const nbr = [];
        if (er > 0)       nbr.push(ei - SIZE);
        if (er < SIZE-1)  nbr.push(ei + SIZE);
        if (ec > 0)       nbr.push(ei - 1);
        if (ec < SIZE-1)  nbr.push(ei + 1);
        const ni = nbr[Math.floor(Math.random() * nbr.length)];
        [board[ei], board[ni]] = [board[ni], board[ei]];
      }
    }
    shuffle();

    function slideAt(idx) {
      if (solved) return;
      const ei  = board.indexOf(0);
      const er  = Math.floor(ei / SIZE), ec = ei % SIZE;
      const tr  = Math.floor(idx / SIZE), tc = idx % SIZE;
      const adj = (er === tr && Math.abs(ec - tc) === 1) ||
                  (ec === tc && Math.abs(er - tr) === 1);
      if (!adj) return;
      [board[ei], board[idx]] = [board[idx], board[ei]];
      moves++;
      if (board.join() === GOAL.join()) {
        solved = true;
        endTimer = setTimeout(() => onDone(true), 900);
      }
    }

    canvas.addEventListener('click', e => {
      const rect = canvas.getBoundingClientRect();
      const mx   = (e.clientX - rect.left) * (canvas.width  / rect.width / (window.devicePixelRatio || 1));
      const my   = (e.clientY - rect.top)  * (canvas.height / rect.height);
      for (let i = 0; i < SIZE * SIZE; i++) {
        const c = i % SIZE, r = Math.floor(i / SIZE);
        const x = OX + c * cellW, y = OY + r * cellH;
        if (mx >= x && mx < x + cellW - 4 && my >= y && my < y + cellH - 4)
          slideAt(i);
      }
    });

    const onKey = e => {
      const ei = board.indexOf(0);
      const map = { ArrowUp: SIZE, ArrowDown: -SIZE, ArrowLeft: 1, ArrowRight: -1 };
      const di  = map[e.key];
      if (di && ei + di >= 0 && ei + di < SIZE * SIZE) {
        e.preventDefault();
        slideAt(ei + di);
      }
    };
    document.addEventListener('keydown', onKey);

    function loop() {
      if (stopped) return;
      raf = requestAnimationFrame(loop);

      ctx.fillStyle = '#050508';
      ctx.fillRect(0, 0, W, H);

      MGAPI.text(ctx, `🧩 Züge: ${moves}`, W / 2, 18, { size: 12, color: theme.primary });

      for (let i = 0; i < SIZE * SIZE; i++) {
        const val = board[i];
        const c   = i % SIZE, r = Math.floor(i / SIZE);
        const x   = OX + c * cellW, y = OY + r * cellH;

        if (val === 0) {
          // Leerfeld
          MGAPI.roundRect(ctx, x+2, y+2, cellW-8, cellH-8, 8, 'rgba(255,255,255,0.03)', null);
          continue;
        }

        const isCorrect = val === GOAL[i];
        MGAPI.roundRect(ctx, x+2, y+2, cellW-8, cellH-8, 10,
          isCorrect ? `${theme.primary}33` : 'rgba(255,255,255,0.07)',
          isCorrect ? theme.primary        : 'rgba(255,255,255,0.15)');

        MGAPI.text(ctx, String(val), x + cellW/2 - 2, y + cellH/2 + 2,
          { size: Math.floor(cellH * 0.38), family: "'Fredoka One',cursive",
            color: isCorrect ? theme.primary : '#fff' });
      }

      if (solved)
        MGAPI.resultScreen(ctx, W, H, true, `In ${moves} Zügen gelöst!`);
    }

    raf = requestAnimationFrame(loop);
    return {
      stop() {
        stopped = true;
        clearTimeout(endTimer);
        cancelAnimationFrame(raf);
        document.removeEventListener('keydown', onKey);
      },
    };
  }

  function launch(wrap, W, H, cfg)  { return run(wrap, W, H, cfg, won => MGAPI.onResult(won)); }
  function preview(wrap, W, H, cfg) { return run(wrap, W, H, cfg, won => MGAPI.onResult(won)); }

  return { id: ID, emoji: EMOJI, name: NAME, desc: DESC, controls: CONTROLS, multi: MULTI, launch, preview };

})();