// Top-down "Dogpit" arena simulation. Same authoritative/DOM-free contract and
// export surface as sim.js — main.js picks the module per match.
//
// The plane is x/y; z is hop height (a third axis for dodging ground hazards
// and crossing pits). KOs come from being knocked into pits, not blast zones.
import { TILE, GW, GH, W, H, T, B, STOCKS, ITEMS } from './consts.js';
import { makeRng } from './rng.js';
import { generateArena } from './mapgen_arena.js';
import { sawPos } from './mapgen.js';
import { moveEntity, tileAt, raycast, boxFree } from './physics.js';
import { CHARS } from './characters.js';

const PW = 18, PH = 14;
const ZGRAV = 0.34;
const VCAP = TILE - 2.5; // collision is single-pass AABB; stay under tile size

export function createGame(seed, defs) {
  const map = generateArena(seed);
  const g = {
    kind: 'arena', seed, tick: 0, map, players: [], ents: [], nextEnt: 1,
    rng: makeRng((seed ^ 0xD06600D) >>> 0),
    events: [], over: null, overT: 0, freeze: 170, dropTimer: 550,
  };
  defs.forEach((d, i) => g.players.push(makePlayer(d, i, map)));
  return g;
}

function makePlayer(d, i, map) {
  const sp = map.spawns[i % map.spawns.length];
  return {
    idx: i, charId: d.charId, name: d.name || CHARS[d.charId].name,
    x: sp.x, y: sp.y, vx: 0, vy: 0, z: 0, vz: 0, ang: i % 2 ? Math.PI : 0,
    w: PW, h: PH, face: i % 2 ? -1 : 1, falling: 0,
    onGround: true, landT: 0,
    dmg: 0, stocks: STOCKS, respawn: 0, invuln: 90,
    atkCd: 0, atkT: 0, hitMask: 0, minedSet: {},
    hitstun: 0, item: null, ammo: 0, shield: 0, boost: 0,
    prev: 0, st: {}, wallHit: 0,
  };
}

const alive = (p) => p.stocks > 0 && p.respawn <= 0 && p.falling <= 0;

export function step(g, inputs) {
  g.tick++;
  g.events.length = 0;
  if (g.freeze > 0) {
    g.freeze--;
    if (g.freeze === 0) g.events.push({ t: 'go' });
  }
  const frozen = g.freeze > 0 || !!g.over;

  for (const p of g.players) {
    const inp = frozen ? 0 : (inputs[p.idx] || 0);
    stepPlayer(g, p, inp, inp & ~p.prev);
    p.prev = inp;
  }
  stepEnts(g);
  stepSaws(g);

  if (!g.over && --g.dropTimer <= 0) {
    g.dropTimer = 520 + g.rng.int(0, 300);
    // care package lands on a random clear floor tile
    for (let t = 0; t < 40; t++) {
      const tx = g.rng.int(3, GW - 4), ty = g.rng.int(3, GH - 4);
      if (tileAt(g.map, tx, ty) === T.EMPTY) {
        spawnPickup(g, tx * TILE + 6, ty * TILE + 6, g.rng.pick(ITEMS));
        g.events.push({ t: 'drop' });
        break;
      }
    }
  }

  checkEnd(g);
  return g.events;
}

function stepPlayer(g, p, inp, pressed) {
  if (p.stocks <= 0) return;
  if (p.respawn > 0) {
    p.respawn--;
    if (p.respawn === 0) respawn(g, p);
    return;
  }
  // mid-fall into a pit: no control, shrink, then KO
  if (p.falling > 0) {
    p.falling--;
    p.vx *= 0.88; p.vy *= 0.88;
    p.x += p.vx; p.y += p.vy;
    if (p.falling === 0) kill(g, p);
    return;
  }

  const c = CHARS[p.charId], s = c.stats, st = p.st;
  if (p.invuln > 0 && g.freeze <= 0) p.invuln--;
  if (p.atkCd > 0) p.atkCd--;
  if (p.shield > 0) p.shield--;
  if (p.boost > 0) p.boost--;
  if (p.landT > 0) p.landT--;

  const bm = p.boost > 0 ? 1.45 : 1;
  const stunned = p.hitstun > 0;
  if (stunned) p.hitstun--;

  // --- 8-way movement ---
  const dx = (inp & B.L ? -1 : 0) + (inp & B.R ? 1 : 0);
  const dy = (inp & B.U ? -1 : 0) + (inp & B.D ? 1 : 0);
  if (!stunned && !(st.charge > 0) && !st.anchor) {
    if (dx || dy) {
      const n = Math.hypot(dx, dy), ux = dx / n, uy = dy / n;
      const acc = s.accel * (p.z > 0 ? 0.55 : 1) * bm;
      p.vx += ux * acc;
      p.vy += uy * acc;
      const cap = s.run * bm, spd = Math.hypot(p.vx, p.vy);
      if (spd > cap) { // let dash overspeed decay instead of hard-clamping
        const k = Math.max(cap, spd - s.accel * 2) / spd;
        p.vx *= k; p.vy *= k;
      }
      p.ang = Math.atan2(uy, ux);
      if (dx) p.face = dx > 0 ? 1 : -1;
    } else if (p.z <= 0) {
      p.vx *= s.fric; p.vy *= s.fric;
      if (Math.hypot(p.vx, p.vy) < 0.1) { p.vx = 0; p.vy = 0; }
    } else {
      p.vx *= 0.99; p.vy *= 0.99;
    }
  } else if (stunned && p.z <= 0) {
    p.vx *= 0.9; p.vy *= 0.9;
  }

  // --- hop ---
  if (!stunned && (pressed & B.HOP) && p.z <= 0) {
    p.vz = 3.0;
    g.events.push({ t: 'jump', x: p.x, y: p.y });
  }

  // --- character specials ---
  updateCharArena(g, p, c, inp, pressed);

  // --- z physics ---
  const wasAir = p.z > 0;
  p.z += p.vz;
  if (!st.hover) p.vz -= ZGRAV;
  let justLanded = false;
  if (p.z <= 0) {
    if (wasAir) {
      justLanded = true;
      p.landT = 6;
      if (-p.vz > 2) g.events.push({ t: 'land', x: p.x, y: p.y + 5, v: 4 });
    }
    p.z = 0;
    if (p.vz < 0) p.vz = 0;
  }
  p.onGround = p.z <= 0;

  if (justLanded && st.pound) {
    st.pound = false;
    g.events.push({ t: 'pound', x: p.x, y: p.y });
    for (const o of g.players) {
      if (o === p || !alive(o) || o.z > 6) continue;
      const ox = o.x - p.x, oy = o.y - p.y, d = Math.hypot(ox, oy);
      if (d < 55) { const n = d || 1; hurt(g, o, 9, ox / n, oy / n, 6); }
    }
  }

  // --- integrate & wall-collide (y-axis hits count as walls here too) ---
  const res = moveEntity(p, g.map, {});
  p.wallHit = res.wall || ((res.ground || res.ceil) ? 2 : 0);

  // --- ground tile sensors ---
  if (p.z <= 0) {
    const t = tileAt(g.map, Math.floor(p.x / TILE), Math.floor(p.y / TILE));
    if (t === T.PIT) {
      p.falling = 36;
      p.atkT = 0; p.st.charge = 0; p.st.anchor = null;
      g.events.push({ t: 'fall', x: p.x, y: p.y });
      return;
    }
    if (t === T.PADTOP && p.vz <= 0) {
      p.vz = 4.6;
      g.events.push({ t: 'pad', x: p.x, y: p.y });
    }
    // spikes under any part of the footprint
    const hw = p.w / 2, hh = p.h / 2;
    const x0 = Math.floor((p.x - hw) / TILE), x1 = Math.floor((p.x + hw) / TILE);
    const y0 = Math.floor((p.y - hh) / TILE), y1 = Math.floor((p.y + hh) / TILE);
    for (let ty = y0; ty <= y1; ty++) for (let tx = x0; tx <= x1; tx++) {
      if (tileAt(g.map, tx, ty) === T.SPIKE) {
        const sx = tx * TILE + 6, sy = ty * TILE + 6;
        const n = Math.hypot(p.x - sx, p.y - sy) || 1;
        if (hurt(g, p, 9, (p.x - sx) / n, (p.y - sy) / n, 5.5)) {
          g.events.push({ t: 'spike', x: p.x, y: p.y });
        }
      }
    }
  }

  // --- attack ---
  if (!stunned && (pressed & B.ATK) && p.atkCd <= 0) {
    p.atkCd = 24; p.atkT = 7;
    p.hitMask = 0; p.minedSet = {};
    p.vx += Math.cos(p.ang) * 1.4;
    p.vy += Math.sin(p.ang) * 1.4;
    g.events.push({ t: 'bark', x: p.x, y: p.y, f: p.face });
  }
  if (p.atkT > 0) { p.atkT--; doAttack(g, p); }

  if (!stunned && (pressed & B.ITM) && p.item) useItem(g, p);
}

function updateCharArena(g, p, c, inp, pressed) {
  const st = p.st;
  const inputDir = () => {
    const dx = (inp & B.L ? -1 : 0) + (inp & B.R ? 1 : 0);
    const dy = (inp & B.U ? -1 : 0) + (inp & B.D ? 1 : 0);
    if (dx || dy) { const n = Math.hypot(dx, dy); return [dx / n, dy / n]; }
    return [Math.cos(p.ang), Math.sin(p.ang)];
  };
  switch (c.key) {

    case 'bolt': { // zoom dash, on a cooldown instead of landing-reset
      if (st.dashCd > 0) st.dashCd--;
      if ((pressed & B.SPC) && st.dashCd <= 0 && p.hitstun <= 0) {
        const [ux, uy] = inputDir();
        p.vx = ux * 8.6; p.vy = uy * 8.6;
        p.ang = Math.atan2(uy, ux);
        st.dashCd = 50;
        g.events.push({ t: 'dash', x: p.x, y: p.y });
      }
      break;
    }

    case 'tank': {
      if (st.chargeCd > 0) st.chargeCd--;
      if (st.charge > 0) {
        st.charge--;
        p.vx = Math.cos(st.chargeAng) * 6.4;
        p.vy = Math.sin(st.chargeAng) * 6.4;
        for (const o of g.players) {
          if (o !== p && alive(o) && o.z < 6 &&
              Math.abs(o.x - p.x) < 18 && Math.abs(o.y - p.y) < 16) {
            hurt(g, o, 10, Math.cos(st.chargeAng), Math.sin(st.chargeAng), 6.5);
            st.charge = 0;
          }
        }
        if (p.wallHit) { // x or y wall — stepPlayer encodes both
          st.charge = 0;
          g.events.push({ t: 'thud', x: p.x, y: p.y });
        }
      } else if ((pressed & B.SPC) && p.hitstun <= 0) {
        if (p.z <= 0 && st.chargeCd <= 0) {
          st.charge = 34; st.chargeCd = 80; st.chargeAng = p.ang;
          g.events.push({ t: 'charge', x: p.x, y: p.y });
        } else if (p.z > 0 && !st.pound) {
          st.pound = true;
          p.vz = -4.5; // slam down
        }
      }
      break;
    }

    case 'swing': { // zip-leash: latch a wall, get reeled in, slingshot out
      if (st.anchor) {
        if (pressed & B.SPC) { st.anchor = null; break; }
        const dx = st.anchor.x - p.x, dy = st.anchor.y - p.y;
        const d = Math.hypot(dx, dy) || 1;
        if (d < 16 || (pressed & B.HOP)) { // arrived, or slingshot release
          st.anchor = null;
          p.vx *= 1.18; p.vy *= 1.18;
          break;
        }
        const ux = dx / d, uy = dy / d;
        p.vx += (ux * 7 - p.vx) * 0.25;
        p.vy += (uy * 7 - p.vy) * 0.25;
        p.ang = Math.atan2(uy, ux);
      } else if ((pressed & B.SPC) && p.hitstun <= 0) {
        const hit = raycast(g.map, p.x, p.y, Math.cos(p.ang), Math.sin(p.ang), 175);
        if (hit) {
          st.anchor = { x: hit.x, y: hit.y };
          g.events.push({ t: 'grapple', x: hit.x, y: hit.y });
        } else {
          g.events.push({ t: 'whiff', x: p.x, y: p.y });
        }
      }
      break;
    }

    case 'wisp': { // blink works exactly as in side view — through walls, over pits
      if (st.blinkCd > 0) st.blinkCd--;
      if ((pressed & B.SPC) && st.blinkCd <= 0 && p.hitstun <= 0) {
        const [ux, uy] = inputDir();
        for (let dist = 58; dist >= 12; dist -= 6) {
          const tx = p.x + ux * dist, ty = p.y + uy * dist;
          if (boxFree(g.map, tx, ty, p.w, p.h)) {
            g.events.push({ t: 'blink', x: p.x, y: p.y, x2: tx, y2: ty });
            p.x = tx; p.y = ty;
            p.vx = ux * 3.5; p.vy = uy * 3.5;
            p.ang = Math.atan2(uy, ux);
            st.blinkCd = 48;
            break;
          }
        }
      }
      break;
    }

    case 'rocket': { // hover: floats over pits/spikes/saws while fuel lasts
      st.hover = false;
      if (p.z <= 0) st.fuel = Math.min(70, (st.fuel ?? 70) + 2.4);
      if (st.fuel === undefined) st.fuel = 70;
      if ((inp & B.SPC) && st.fuel > 0 && p.hitstun <= 0) {
        st.fuel -= 1;
        st.hover = true;
        if (p.z < 5) p.vz = Math.max(p.vz, 0.9);
        else { p.z = 5; p.vz = 0; }
        if (g.tick % 5 === 0) g.events.push({ t: 'jet', x: p.x, y: p.y + 4 });
      }
      break;
    }
  }
}

function doAttack(g, p) {
  const ax = p.x + Math.cos(p.ang) * 17, ay = p.y + Math.sin(p.ang) * 17;
  const aw = 22, ah = 20;
  for (const o of g.players) {
    if (o === p || !alive(o)) continue;
    if (p.hitMask & (1 << o.idx)) continue;
    if (Math.abs(o.z - p.z) > 6) continue; // can't bite over/under a hopping dog
    if (Math.abs(o.x - ax) < (aw + o.w) / 2 && Math.abs(o.y - ay) < (ah + o.h) / 2) {
      p.hitMask |= 1 << o.idx;
      const n = Math.hypot(o.x - p.x, o.y - p.y) || 1;
      hurt(g, o, 8, (o.x - p.x) / n, (o.y - p.y) / n, 3.2);
      p.vx *= 0.6; p.vy *= 0.6;
    }
  }
  // crystals are full-height — mineable regardless of z
  const x0 = Math.floor((ax - aw / 2) / TILE), x1 = Math.floor((ax + aw / 2) / TILE);
  const y0 = Math.floor((ay - ah / 2) / TILE), y1 = Math.floor((ay + ah / 2) / TILE);
  for (let ty = y0; ty <= y1; ty++) for (let tx = x0; tx <= x1; tx++) {
    if (tileAt(g.map, tx, ty) !== T.CRYSTAL) continue;
    const i = ty * GW + tx;
    if (p.minedSet[i]) continue;
    p.minedSet[i] = 1;
    const hp = (g.map.hp[i] ?? 3) - 1;
    if (hp <= 0) breakTile(g, tx, ty, true);
    else {
      g.map.hp[i] = hp;
      g.events.push({ t: 'crack', i, hp, x: tx * TILE + 6, y: ty * TILE + 6 });
    }
  }
}

function breakTile(g, tx, ty, drop) {
  const i = ty * GW + tx;
  g.map.tiles[i] = T.EMPTY;
  delete g.map.hp[i];
  g.events.push({ t: 'tile', i, v: T.EMPTY, x: tx * TILE + 6, y: ty * TILE + 6 });
  if (drop) spawnPickup(g, tx * TILE + 6, ty * TILE + 6, g.rng.pick(ITEMS));
}

export function hurt(g, v, dmg, nx, ny, base) {
  if (v.invuln > 0 || v.respawn > 0 || v.stocks <= 0 || v.falling > 0) return false;
  if (v.shield > 0) { g.events.push({ t: 'block', x: v.x, y: v.y }); return false; }
  v.dmg += dmg;
  const m = (base + v.dmg * 0.062) / CHARS[v.charId].stats.weight;
  v.vx = Math.max(-VCAP, Math.min(VCAP, nx * m));
  v.vy = Math.max(-VCAP, Math.min(VCAP, ny * m));
  v.vz = Math.max(v.vz, 1.4); // little pop for juice
  if (v.z <= 0) v.z = 0.01;
  v.hitstun = Math.min(40, 9 + m * 1.6);
  v.invuln = 14;
  v.st.charge = 0; v.st.anchor = null; v.st.pound = false;
  v.atkT = 0;
  g.events.push({ t: 'hit', x: v.x, y: v.y, m });
  return true;
}

function useItem(g, p) {
  const it = p.item;
  const cx = Math.cos(p.ang), cy = Math.sin(p.ang);
  if (it === 'ball') {
    spawnEnt(g, { k: 'ball', x: p.x + cx * 12, y: p.y + cy * 12, vx: cx * 7 + p.vx * 0.3, vy: cy * 7 + p.vy * 0.3, w: 8, h: 8, own: p.idx, ttl: 240, age: 0 });
    g.events.push({ t: 'throw', x: p.x, y: p.y });
    if (--p.ammo <= 0) p.item = null;
  } else if (it === 'bomb') {
    spawnEnt(g, { k: 'bomb', x: p.x + cx * 10, y: p.y + cy * 10, vx: cx * 4.5 + p.vx * 0.4, vy: cy * 4.5 + p.vy * 0.4, w: 9, h: 9, own: p.idx, fuse: 75, age: 0 });
    g.events.push({ t: 'throw', x: p.x, y: p.y });
    p.item = null;
  } else if (it === 'shield') {
    p.shield = 260; p.item = null;
    g.events.push({ t: 'shield', x: p.x, y: p.y });
  } else if (it === 'boost') {
    p.boost = 320; p.item = null;
    g.events.push({ t: 'boost', x: p.x, y: p.y });
  } else if (it === 'heal') {
    p.dmg = Math.max(0, p.dmg - 35); p.item = null;
    g.events.push({ t: 'heal', x: p.x, y: p.y });
  }
}

function spawnEnt(g, e) {
  e.id = g.nextEnt++;
  g.ents.push(e);
  return e;
}

function spawnPickup(g, x, y, item) {
  spawnEnt(g, { k: 'pickup', x, y, vx: 0, vy: 0, w: 10, h: 10, item, ttl: 1400 });
}

function stepEnts(g) {
  for (const e of g.ents) {
    if (e.k === 'pickup') {
      e.ttl--;
      for (const p of g.players) {
        if (alive(p) && !p.item && Math.abs(p.x - e.x) < 14 && Math.abs(p.y - e.y) < 14) {
          p.item = e.item;
          if (e.item === 'ball') p.ammo = 3;
          e.dead = true;
          g.events.push({ t: 'pickup', x: e.x, y: e.y, item: e.item });
          break;
        }
      }
      if (e.ttl <= 0) e.dead = true;

    } else if (e.k === 'ball') {
      e.age++; e.ttl--;
      const pvx = e.vx, pvy = e.vy;
      const r = moveEntity(e, g.map, {});
      if (r.wall) e.vx = -pvx * 0.85;
      if (r.ground || r.ceil) e.vy = -pvy * 0.85; // top-down: ±y walls bounce too
      for (const p of g.players) {
        if (!alive(p) || p.z > 6) continue;
        if (p.idx === e.own && e.age < 30) continue;
        if (Math.abs(p.x - e.x) < (p.w + e.w) / 2 && Math.abs(p.y - e.y) < (p.h + e.h) / 2) {
          const n = Math.hypot(pvx, pvy) || 1;
          hurt(g, p, 6, pvx / n, pvy / n, 3.5);
          e.dead = true;
          break;
        }
      }
      // balls sail over pits (they're light); they just expire
      if (e.ttl <= 0) e.dead = true;

    } else if (e.k === 'bomb') {
      e.age++; e.fuse--;
      e.vx *= 0.96; e.vy *= 0.96; // slides to a stop
      const pvx = e.vx, pvy = e.vy;
      const r = moveEntity(e, g.map, {});
      if (r.wall) e.vx = -pvx * 0.6;
      if (r.ground || r.ceil) e.vy = -pvy * 0.6;
      // a bomb sliding onto a pit drops in
      if (tileAt(g.map, Math.floor(e.x / TILE), Math.floor(e.y / TILE)) === T.PIT) { e.dead = true; continue; }
      let contact = false;
      for (const p of g.players) {
        if (!alive(p) || p.z > 8) continue;
        if (p.idx === e.own && e.age < 15) continue;
        if (Math.abs(p.x - e.x) < 12 && Math.abs(p.y - e.y) < 12) { contact = true; break; }
      }
      if (e.fuse <= 0 || contact) { explode(g, e.x, e.y); e.dead = true; }
    }
  }
  g.ents = g.ents.filter(e => !e.dead);
}

function explode(g, x, y) {
  g.events.push({ t: 'boom', x, y });
  for (const p of g.players) {
    if (!alive(p) || p.z > 8) continue;
    const dx = p.x - x, dy = p.y - y;
    const d = Math.hypot(dx, dy);
    if (d < 48) {
      const n = d || 1;
      hurt(g, p, 14, dx / n, dy / n, 7);
    }
  }
  const tx0 = Math.floor((x - 48) / TILE), tx1 = Math.floor((x + 48) / TILE);
  const ty0 = Math.floor((y - 48) / TILE), ty1 = Math.floor((y + 48) / TILE);
  for (let ty = ty0; ty <= ty1; ty++) for (let tx = tx0; tx <= tx1; tx++) {
    if (tileAt(g.map, tx, ty) === T.CRYSTAL &&
        Math.hypot(tx * TILE + 6 - x, ty * TILE + 6 - y) < 48) {
      breakTile(g, tx, ty, true);
    }
  }
}

function stepSaws(g) {
  for (const s of g.map.saws) {
    const pos = sawPosOf(s);
    s.prog += s.speed / (pos.total || 1);
    s.x = pos.x; s.y = pos.y;
    if (g.freeze > 0 || g.over) continue;
    for (const p of g.players) {
      if (!alive(p) || p.z > 5) continue; // hop over the blade
      const dx = p.x - s.x, dy = p.y - s.y;
      const d = Math.hypot(dx, dy);
      if (d < 16) {
        const n = d || 1;
        if (hurt(g, p, 12, dx / n, dy / n, 6.5)) {
          g.events.push({ t: 'saw', x: p.x, y: p.y });
        }
      }
    }
  }
}

function sawPosOf(s) { return sawPos(s, s.prog); }

function kill(g, p) {
  p.stocks--;
  g.events.push({
    t: 'ko', idx: p.idx,
    x: Math.max(20, Math.min(W - 20, p.x)),
    y: Math.max(20, Math.min(H - 20, p.y)),
  });
  p.st = {}; p.item = null; p.ammo = 0; p.shield = 0; p.boost = 0;
  p.vx = 0; p.vy = 0; p.vz = 0; p.z = 0; p.falling = 0;
  p.hitstun = 0; p.atkT = 0; p.dmg = 0;
  p.x = -1000; p.y = -1000;
  p.respawn = p.stocks > 0 ? 80 : 0;
}

function respawn(g, p) {
  let best = g.map.spawns[0], bd = -1;
  for (const sp of g.map.spawns) {
    let d = 1e9;
    for (const o of g.players) {
      if (o !== p && alive(o)) d = Math.min(d, Math.hypot(o.x - sp.x, o.y - sp.y));
    }
    if (d > bd) { bd = d; best = sp; }
  }
  p.x = best.x; p.y = best.y;
  p.vx = 0; p.vy = 0; p.z = 0; p.vz = 0;
  p.invuln = 90; p.dmg = 0;
  g.events.push({ t: 'respawn', x: p.x, y: p.y });
}

function checkEnd(g) {
  if (g.over) { g.overT++; return; }
  const standing = g.players.filter(p => p.stocks > 0);
  if (standing.length <= 1 && g.players.length > 1) {
    g.over = { winner: standing[0] ? standing[0].idx : -1 };
    g.overT = 0;
    g.events.push({ t: 'over', winner: g.over.winner });
  }
}

// --- snapshots: same contract as sim.js, plus z / facing-angle / falling ---
export function snapshot(g, events) {
  return {
    tick: g.tick, freeze: g.freeze, over: g.over, overT: g.overT,
    p: g.players.map(p => ({
      x: +p.x.toFixed(1), y: +p.y.toFixed(1),
      vx: +p.vx.toFixed(2), vy: +p.vy.toFixed(2),
      z: +p.z.toFixed(1), fa: +p.ang.toFixed(2), fl: p.falling,
      f: p.face, d: Math.round(p.dmg), s: p.stocks,
      og: p.z <= 0 ? 1 : 0, lt: p.landT | 0,
      r: p.respawn, iv: p.invuln, hs: p.hitstun, a: p.atkT,
      it: p.item, am: p.ammo, sh: p.shield, bo: p.boost,
      st: {
        an: p.st.anchor ? [Math.round(p.st.anchor.x), Math.round(p.st.anchor.y)] : 0,
        ch: p.st.charge > 0 ? 1 : 0, cc: p.st.chargeCd | 0,
        jet: p.st.hover ? 1 : 0, fu: p.st.fuel | 0,
        po: p.st.pound ? 1 : 0, da: (p.st.dashCd | 0) <= 0 ? 1 : 0, bc: p.st.blinkCd | 0,
      },
    })),
    e: g.ents.map(e => ({ id: e.id, k: e.k, x: Math.round(e.x), y: Math.round(e.y), item: e.item, f: e.fuse })),
    sw: g.map.saws.map(s => [Math.round(s.x || 0), Math.round(s.y || 0)]),
    ev: events,
  };
}

export function applySnapshot(g, s) {
  g.tick = s.tick; g.freeze = s.freeze; g.over = s.over; g.overT = s.overT;
  s.p.forEach((sp, i) => {
    const p = g.players[i];
    if (!p) return;
    p.x = sp.x; p.y = sp.y; p.vx = sp.vx; p.vy = sp.vy;
    p.z = sp.z; p.ang = sp.fa; p.falling = sp.fl;
    p.face = sp.f; p.dmg = sp.d; p.stocks = sp.s;
    p.onGround = !!sp.og; p.landT = sp.lt;
    p.respawn = sp.r; p.invuln = sp.iv; p.hitstun = sp.hs; p.atkT = sp.a;
    p.item = sp.it; p.ammo = sp.am; p.shield = sp.sh; p.boost = sp.bo;
    p.st = {
      anchor: sp.st.an ? { x: sp.st.an[0], y: sp.st.an[1] } : null,
      charge: sp.st.ch, chargeCd: sp.st.cc, hover: sp.st.jet, jet: sp.st.jet,
      fuel: sp.st.fu, pound: sp.st.po, dash: sp.st.da, blinkCd: sp.st.bc,
    };
  });
  g.ents = s.e.map(e => ({ ...e, fuse: e.f, vx: 0, vy: 0, w: 8, h: 8 }));
  s.sw.forEach((xy, i) => {
    const saw = g.map.saws[i];
    if (saw) { saw.x = xy[0]; saw.y = xy[1]; }
  });
  for (const ev of s.ev) {
    if (ev.t === 'tile') { g.map.tiles[ev.i] = ev.v; delete g.map.hp[ev.i]; }
    else if (ev.t === 'crack') g.map.hp[ev.i] = ev.hp;
  }
  return s.ev;
}