/* Reel Royale – ParticleEngine (Canvas, GPU-freundlich) */
export class ParticleEngine {
  constructor(canvas) {
    this.cv = canvas;
    this.ctx = canvas.getContext('2d');
    this.parts = [];
    this.ambient = [];
    this.mode = null;
    this.accent = '#ffce53';
    this.running = false;
    this.dpr = Math.min(window.devicePixelRatio || 1, 2);
    this._resize = this._resize.bind(this);
    window.addEventListener('resize', this._resize);
    this._resize();
  }
  _resize() {
    this.w = this.cv.clientWidth || window.innerWidth;
    this.h = this.cv.clientHeight || window.innerHeight;
    this.cv.width = this.w * this.dpr;
    this.cv.height = this.h * this.dpr;
    this.ctx.setTransform(this.dpr, 0, 0, this.dpr, 0, 0);
  }

  setMode(mode, accent) {
    this.mode = mode;
    if (accent) this.accent = accent;
    this.ambient = [];
    const count = mode ? 46 : 0;
    for (let i = 0; i < count; i++) this.ambient.push(this._spawnAmbient());
    this.start();
  }
  clearMode() { this.mode = null; this.ambient = []; }

  _spawnAmbient() {
    const m = this.mode;
    const base = { x: Math.random() * this.w, y: Math.random() * this.h, ttl: Infinity };
    switch (m) {
      case 'sand':   return { ...base, vx: 0.3 + Math.random(), vy: -0.1 + Math.random() * 0.3, r: 1 + Math.random() * 1.5, c: 'rgba(255,210,120,', a: 0.3 + Math.random() * 0.3, kind: 'dot' };
      case 'ember':  return { ...base, y: this.h + Math.random() * 60, vx: -0.4 + Math.random() * 0.8, vy: -0.6 - Math.random() * 1.1, r: 1 + Math.random() * 2, c: 'rgba(255,140,60,', a: 0.4 + Math.random() * 0.4, kind: 'glow' };
      case 'fire':   return { ...base, y: this.h + Math.random() * 60, vx: -0.5 + Math.random(), vy: -0.9 - Math.random() * 1.5, r: 1.5 + Math.random() * 3, c: 'rgba(255,110,40,', a: 0.4 + Math.random() * 0.5, kind: 'glow' };
      case 'bubble': return { ...base, y: this.h + Math.random() * 60, vx: -0.2 + Math.random() * 0.4, vy: -0.4 - Math.random() * 0.8, r: 2 + Math.random() * 4, c: 'rgba(150,225,255,', a: 0.2 + Math.random() * 0.3, kind: 'ring' };
      case 'leaf':   return { ...base, y: -20, vx: -0.4 + Math.random() * 0.8, vy: 0.4 + Math.random() * 0.7, r: 2 + Math.random() * 2, c: 'rgba(150,220,140,', a: 0.4 + Math.random() * 0.3, kind: 'dot', sway: Math.random() * 6 };
      case 'spark':  return { ...base, vx: -0.3 + Math.random() * 0.6, vy: -0.3 + Math.random() * 0.6, r: 1 + Math.random() * 1.5, c: 'rgba(255,200,110,', a: 0.3 + Math.random() * 0.4, kind: 'glow' };
      default:       return { ...base, vx: 0, vy: 0, r: 1, c: 'rgba(255,255,255,', a: 0.2, kind: 'dot' };
    }
  }

  _stepAmbient(p) {
    p.x += p.vx; p.y += p.vy;
    if (p.sway) p.x += Math.sin(p.y / 30) * 0.4;
    if (p.y < -30 || p.y > this.h + 40 || p.x < -30 || p.x > this.w + 30) Object.assign(p, this._spawnAmbient(), this.mode === 'leaf' ? { y: -20 } : {});
  }

  // ---- Effekte ----
  burst(x, y, kind = 'gold', n = 24) {
    const palette = {
      gold: ['#ffce53', '#ffae2b', '#fff3c2'],
      fire: ['#ff7a2c', '#ff3b3b', '#ffd166'],
      water: ['#56d6ff', '#bdf0ff', '#3fb6d3'],
      confetti: ['#ff5d6c', '#56d6ff', '#4ad991', '#ffce53', '#c77dff'],
      spark: ['#ffe9a8', '#ffce53', '#fff'],
    }[kind] || ['#ffce53'];
    for (let i = 0; i < n; i++) {
      const a = Math.random() * Math.PI * 2;
      const sp = 1 + Math.random() * 6;
      this.parts.push({
        x, y, vx: Math.cos(a) * sp, vy: Math.sin(a) * sp - 2,
        g: 0.12, r: 2 + Math.random() * 3, ttl: 50 + Math.random() * 30, life: 0,
        color: palette[(Math.random() * palette.length) | 0],
        shape: kind === 'confetti' ? 'rect' : 'dot', rot: Math.random() * 6,
      });
    }
    this.start();
  }
  coinShower(n = 60) {
    for (let i = 0; i < n; i++) {
      this.parts.push({
        x: Math.random() * this.w, y: -20 - Math.random() * 200,
        vx: -0.5 + Math.random(), vy: 2 + Math.random() * 4, g: 0.08,
        r: 5 + Math.random() * 5, ttl: 120, life: 0, color: '#ffce53', shape: 'coin', rot: Math.random() * 6,
      });
    }
    this.start();
  }
  confetti(n = 90) {
    for (let i = 0; i < n; i++) {
      this.parts.push({
        x: Math.random() * this.w, y: -20 - Math.random() * 100,
        vx: -1 + Math.random() * 2, vy: 1.5 + Math.random() * 3, g: 0.05,
        r: 3 + Math.random() * 4, ttl: 150, life: 0,
        color: ['#ff5d6c', '#56d6ff', '#4ad991', '#ffce53', '#c77dff'][(Math.random() * 5) | 0],
        shape: 'rect', rot: Math.random() * 6, vr: -0.2 + Math.random() * 0.4,
      });
    }
    this.start();
  }
  /** Feuerwerk: mehrere zeitversetzte Explosionen oben im Bild (für besonders große Gewinne). */
  fireworks(shots = 6) {
    const kinds = ['gold', 'confetti', 'spark', 'fire', 'water'];
    for (let i = 0; i < shots; i++) {
      setTimeout(() => {
        const x = this.w * (0.18 + Math.random() * 0.64);
        const y = this.h * (0.12 + Math.random() * 0.4);
        this.burst(x, y, kinds[(Math.random() * kinds.length) | 0], 28);
      }, i * 360);
    }
  }

  start() { if (!this.running) { this.running = true; requestAnimationFrame(() => this._loop()); } }

  _loop() {
    const ctx = this.ctx;
    ctx.clearRect(0, 0, this.w, this.h);
    // Ambient
    for (const p of this.ambient) {
      this._stepAmbient(p);
      ctx.globalAlpha = p.a;
      ctx.fillStyle = p.c + '1)';
      if (p.kind === 'ring') { ctx.strokeStyle = p.c + '1)'; ctx.lineWidth = 1; ctx.beginPath(); ctx.arc(p.x, p.y, p.r, 0, 7); ctx.stroke(); }
      else if (p.kind === 'glow') { ctx.shadowBlur = 8; ctx.shadowColor = p.c + '1)'; ctx.beginPath(); ctx.arc(p.x, p.y, p.r, 0, 7); ctx.fill(); ctx.shadowBlur = 0; }
      else { ctx.beginPath(); ctx.arc(p.x, p.y, p.r, 0, 7); ctx.fill(); }
    }
    ctx.globalAlpha = 1;
    // Effekt-Partikel
    for (let i = this.parts.length - 1; i >= 0; i--) {
      const p = this.parts[i];
      p.life++; p.vy += p.g; p.x += p.vx; p.y += p.vy; p.rot += (p.vr || 0.05);
      const fade = 1 - p.life / p.ttl;
      if (fade <= 0 || p.y > this.h + 40) { this.parts.splice(i, 1); continue; }
      ctx.globalAlpha = Math.max(0, fade);
      ctx.fillStyle = p.color;
      ctx.save(); ctx.translate(p.x, p.y); ctx.rotate(p.rot);
      if (p.shape === 'rect') ctx.fillRect(-p.r, -p.r / 2, p.r * 2, p.r);
      else if (p.shape === 'coin') {
        ctx.shadowBlur = 8; ctx.shadowColor = '#ffce53';
        ctx.beginPath(); ctx.ellipse(0, 0, p.r * Math.abs(Math.cos(p.rot)) + 1, p.r, 0, 0, 7); ctx.fill();
        ctx.fillStyle = '#b9791a'; ctx.beginPath(); ctx.ellipse(0, 0, p.r * 0.4, p.r * 0.5, 0, 0, 7); ctx.fill();
      } else { ctx.beginPath(); ctx.arc(0, 0, p.r, 0, 7); ctx.fill(); }
      ctx.restore();
    }
    ctx.globalAlpha = 1; ctx.shadowBlur = 0;
    if (this.parts.length || this.ambient.length) requestAnimationFrame(() => this._loop());
    else this.running = false;
  }
}