/**
 * Lane D selftests — player state machine, weather effects, interactions.  (PLAN3D §5-D.5)
 *
 * Everything asserted here is renderer-free: player.sim.js and interact.js import nothing, so this
 * suite is pure logic driven at fixed dt, never rAF. (rAF being throttled in a hidden tab is not
 * theoretical — this lane's dev harness froze mid-knockdown at stateT=0.333 until it was driven by
 * a fixed loop, which is exactly the trap Lane A called out.)
 *
 * The rig half of player.js — bone binding, head-bone scale, clip retarget — can't be asserted
 * headlessly; it needs a GL context and two GLB fetches. That is verified by hand in
 * web/world/dev_player.html and written up in THREADS.md: head bone 1.715 m at fig scale 0.983,
 * all six clips bound, Hips tracks correctly absent.
 */
import { PlayerSim, STATES, TUNE, clipFor } from '../player.sim.js';
import { Interact, wireYardActions } from '../interact.js';
import { assert, assertEq, assertClose, assertLess, fixedLoop } from '../testkit.js';
import { FIXED_DT } from '../contracts.js';
import { loadStorm, createWind } from '../weather.js';

const DT = FIXED_DT;

/** Steady wind blowing +X at `speed` m/s. */
const windX = (speed) => ({ x: speed, y: 0, z: 0 });

/** Drive the sim for `secs` at fixed dt. */
const drive = (sim, secs, input = {}, wind = null, t0 = 0) =>
  fixedLoop(secs, DT, (dt, t) => sim.step(dt, t0 + t, input, wind));

/** Count what a real storm actually does to a person standing mid-yard. */
function stormProfile(wind, tune, secs = 90) {
  const p = new PlayerSim({ start: { x: 0, y: 0, z: 4 }, tune });
  let stumbles = 0, knocks = 0, maxGust = 0, maxWind = 0, shovedFor = 0;
  fixedLoop(secs, DT, (dt, t) => {
    p.step(dt, t, {}, wind);
    maxGust = Math.max(maxGust, p.gust);
    maxWind = Math.max(maxWind, p.windSpeed);
    if (Math.hypot(p.shove.x, p.shove.z) > 0.15) shovedFor += dt;
    for (const e of p.events) if (e.type === 'state') {
      if (e.state === 'stumble') stumbles++;
      if (e.state === 'knocked') knocks++;
    }
    p.events.length = 0;
  });
  return { stumbles, knocks, maxGust, maxWind, shovedFor };
}

/** @param {import('../testkit.js').Suite} t */
export default async function run(t) {
  // The REAL storms, not a mock. Lane D's thresholds are meaningless except against the data they
  // fire on, and this sprint's decision 8 has B+C changing the downdraft semantics underneath us —
  // exactly the kind of edit that silently made StumbleBack unreachable the first time.
  const wild = createWind(await loadStorm('storm_02_wildnight'));
  const calm = createWind(await loadStorm('storm_01_gentle'));
  // ---------------------------------------------------------------- state machine table
  // The 17 clips actually in player_anims.glb (integrator baked the M3 pack; names logged in THREADS).
  // Verified against the real GLB in-browser: SHADES.player.view.clipNames matches this exactly.
  const PACK = new Set(['Idle', 'Walk', 'Run', 'Falling', 'CrouchToStand', 'Reaction',
    'ClimbLadder', 'Crank', 'Dig', 'PickUp', 'Carry', 'CarryTurn', 'CarryIdle', 'StandUp',
    'TakeCover', 'StumbleBack', 'PlantSeeds']);

  t.test('state table: every state\'s clip exists in player_anims.glb', () => {
    for (const [name, st] of Object.entries(STATES)) {
      assert(PACK.has(st.clip), `state ${name} wants missing clip ${st.clip}`);
      if (st.carryClip) assert(PACK.has(st.carryClip), `state ${name} wants missing ${st.carryClip}`);
    }
  });

  t.test('clipFor: carrying swaps the locomotion set, an interaction names its own verb', () => {
    const s = new PlayerSim();
    assertEq(clipFor(s), 'Idle', 'empty-handed idle');
    s.state = 'walk'; assertEq(clipFor(s), 'Walk');
    s.carrying = 'spare';
    assertEq(clipFor(s), 'Carry', 'carrying while walking');
    s.state = 'run'; assertEq(clipFor(s), 'Carry', 'no CarryRun clip exists — Carry covers it');
    s.state = 'idle'; assertEq(clipFor(s), 'CarryIdle', 'carrying while standing');
    s.state = 'busy'; s.busyClip = 'Crank';
    assertEq(clipFor(s), 'Crank', 'the verb wins over the carry set while busy');
    s.busyClip = null;
    assertEq(clipFor(s), 'Idle', 'busy with no named verb falls back to the table');
    // locked states have no carry variant — you drop what you held anyway
    s.carrying = 'spare'; s.state = 'knocked';
    assertEq(clipFor(s), 'Falling', 'knockdown always plays Falling');
  });

  t.test('state table: no stuck states — every locked state drains to a free one', () => {
    for (const [name, st] of Object.entries(STATES)) {
      if (!st.locked) continue;
      assert((st.next && st.secs > 0) || !!st.releasedBy,
        `locked state ${name} has neither a timed exit nor an external releaser`);
      if (st.next) assert(!!STATES[st.next], `state ${name}.next=${st.next} is not a state`);
    }
    for (const name of Object.keys(STATES)) {
      let cur = name, hops = 0;
      const seen = new Set();
      while (STATES[cur].locked && STATES[cur].next && hops < 16 && !seen.has(cur)) {
        seen.add(cur); cur = STATES[cur].next; hops++;
      }
      assert(!STATES[cur].locked || !!STATES[cur].releasedBy,
        `state ${name} chains into a dead end at ${cur}`);
    }
  });

  // ---------------------------------------------------------------- locomotion
  t.test('locomotion: idle -> walk -> run -> idle at the tuned speeds', () => {
    const sim = new PlayerSim();
    assertEq(sim.state, 'idle', 'spawns idle');
    assert(!sim.busy, 'idle is not busy');

    drive(sim, 1.0, { x: 0, z: 1, camYaw: 0 });
    assertEq(sim.state, 'walk', 'W walks');
    assertClose(sim.speed, TUNE.walkSpeed, 0.05, 'walk speed');

    drive(sim, 1.0, { x: 0, z: 1, run: true, camYaw: 0 });
    assertEq(sim.state, 'run', 'shift runs');
    assertClose(sim.speed, TUNE.runSpeed, 0.05, 'run speed');

    drive(sim, 1.0, {});
    assertEq(sim.state, 'idle', 'releasing input returns to idle');
    assertLess(sim.speed, 0.15, 'and stops');
  });

  t.test('locomotion: movement is relative to camera.yaw', () => {
    const a = new PlayerSim(); drive(a, 1.0, { x: 0, z: 1, camYaw: 0 });
    assertLess(a.pos.z, -0.5, 'at yaw 0, W drives -Z (three.js camera-forward)');
    assertClose(a.pos.x, 0, 1e-6, 'and not sideways');

    const b = new PlayerSim(); drive(b, 1.0, { x: 0, z: 1, camYaw: Math.PI / 2 });
    assertLess(b.pos.x, -0.5, 'at yaw 90 deg, the same key drives -X');
    assertClose(b.pos.z, 0, 1e-6, 'and not forward');

    assertClose(Math.abs(a.facing), Math.PI, 0.05, 'facing chases the movement direction');
  });

  // ---------------------------------------------------------------- weather on the player
  t.test('weather: wind slows you, capped at TUNE.slowMax', () => {
    const calm = new PlayerSim(); drive(calm, 2, { x: 0, z: 1, camYaw: 0 }, windX(0));
    const blow = new PlayerSim(); drive(blow, 2, { x: 0, z: 1, camYaw: 0 }, windX(20));
    assertLess(blow.speed, calm.speed, 'wind slows you');

    // Isolate the slow curve from the knockdown — in a real 1e4 m/s you are flat on your back
    // inside half a second (which is correct, and is what this assert used to accidentally measure).
    const gale = new PlayerSim({ tune: { knockWind: Infinity } });
    drive(gale, 2, { x: 0, z: 1, camYaw: 0 }, windX(1e4));
    assertClose(gale.speed, TUNE.walkSpeed * (1 - TUNE.slowMax), 0.05,
      'slow saturates at slowMax and never goes past it');
  });

  t.test('weather: steady wind reads as baseline, not as a gust', () => {
    const s = new PlayerSim();
    drive(s, 60, {}, windX(20));
    assertLess(s.gust, 1.0, 'the EMA learns a constant 20 m/s as base');
    assertLess(Math.hypot(s.shove.x, s.shove.z), 0.05, 'so it does not shove you forever');
  });

  t.test('weather: a gust over the baseline shoves you downwind, and scales with speed squared', () => {
    const s = new PlayerSim();
    drive(s, 30, {}, windX(6));            // learn a calm baseline
    const x0 = s.pos.x;
    drive(s, 1.6, {}, windX(22), 30);      // 16 m/s over baseline -> past shoveGustMin
    assert(s.pos.x - x0 > 0.05, `gust should shove downwind, dx=${(s.pos.x - x0).toFixed(3)}`);

    const push = (ws) => {
      const p = new PlayerSim();
      drive(p, 30, {}, windX(2));
      const p0 = p.pos.x;
      drive(p, 1.0, {}, windX(ws), 30);
      return p.pos.x - p0;
    };
    const p15 = push(15), p30 = push(30);
    assert(p30 > p15 * 2.5,
      `shove must grow faster than linearly with speed: ${p15.toFixed(3)} -> ${p30.toFixed(3)}`);
  });

  // ---------------------------------------------------------------- knockdown
  t.test('knockdown: needs SUSTAINED overload, like a sail corner letting go', () => {
    const brief = new PlayerSim();
    drive(brief, 0.3, {}, windX(TUNE.knockWind + 5));
    assert(brief.state !== 'knocked', 'a brief spike must not put you down');

    const held = new PlayerSim();
    held.carrying = 'spare';
    drive(held, TUNE.knockSustain + 0.2, {}, windX(TUNE.knockWind + 5));
    assertEq(held.state, 'knocked', 'sustained overload does');
    assertEq(held.carrying, null, 'and drops what you were carrying');
    assert(held.knockDir.x > 0.99, 'and you fall downwind');
  });

  t.test('knockdown: exposure bleeds off — flickering gusts never creep into one', () => {
    const s = new PlayerSim();
    fixedLoop(10, DT, (dt, t) => {
      const on = Math.round(t / DT) % 40 < 10;        // 0.17 s on, 0.5 s off
      s.step(dt, t, {}, windX(on ? TUNE.knockWind + 5 : 5));
    });
    assert(s.state !== 'knocked',
      `flickering gusts must not accumulate (exposure=${s.exposure.toFixed(3)})`);
  });

  t.test('knockdown: knocked -> getup -> idle, unaided, and upright again', () => {
    const s = new PlayerSim();
    s.knockdown(0);
    assert(s.busy, 'knocked is locked');
    drive(s, 0.5, { x: 0, z: 1, camYaw: 0 });
    assertClose(s.pos.z, 0, 1e-9, 'knocked ignores movement input');
    assert(s.pitch > 0.99, 'body goes flat');
    drive(s, 1.1, {});
    assertEq(s.state, 'getup', 'knocked drains to getup on its own');
    drive(s, 1.4, {});
    assertEq(s.state, 'idle', 'getup drains to idle on its own');
    assertLess(s.pitch, 0.01, 'and the body is upright again');
    assert(!s.busy, 'player is free');
  });

  // ---------------------------------------------------------------- shelter (hold C)
  t.test('shelter: bracing survives a gust that floors you standing', () => {
    const gust = TUNE.knockWind + 8;                       // over the standing bar, under the braced one
    const standing = new PlayerSim();
    drive(standing, TUNE.knockSustain + 0.3, {}, windX(gust));
    assertEq(standing.state, 'knocked', 'standing, this gust floors you');

    const braced = new PlayerSim();
    drive(braced, TUNE.knockSustain + 0.3, { shelter: true }, windX(gust));
    assertEq(braced.state, 'shelter', 'braced, the same gust does not');
    assert(braced.busy, 'shelter is locked — you cannot walk while braced');
  });

  t.test('shelter: raises the bar, it does not remove it', () => {
    const s = new PlayerSim();
    drive(s, TUNE.knockSustain + 0.2, { shelter: true }, windX(TUNE.knockWind * TUNE.shelterKnockMult + 5));
    assertEq(s.state, 'knocked', 'a big enough gust still takes you off your feet, braced or not');
  });

  t.test('shelter: releasing the key always frees you — you are never stuck braced', () => {
    // steady wind (already learned as baseline, so no apparent gust): straight back to idle
    const s = new PlayerSim();
    drive(s, 30, {}, windX(20));
    drive(s, 1, { shelter: true }, windX(20));
    assertEq(s.state, 'shelter', 'braced');
    drive(s, 0.5, {}, windX(20));
    assertEq(s.state, 'idle', 'let go in steady wind → idle');
    assert(!s.busy, 'and free to move');
  });

  t.test('shelter: unbracing INTO the gust you were hiding from costs you your footing', () => {
    // Emergent, and worth pinning: bracing is a commitment. Let go early and the gust takes you.
    // This is what makes "wait for the lull" a decision rather than a formality.
    const g = new PlayerSim();
    drive(g, 30, {}, windX(4));                                   // learn a calm baseline
    drive(g, 1, { shelter: true }, windX(4 + TUNE.stumbleGust + 6), 30);
    assertEq(g.state, 'shelter', 'braced through the gust');
    drive(g, 0.2, {}, windX(4 + TUNE.stumbleGust + 6), 31);
    assert(g.state !== 'shelter', 'releasing always leaves shelter');
    assertEq(g.state, 'stumble', 'and straight into the gust → you stumble');
  });

  t.test('shelter: cannot brace from your back', () => {
    const s = new PlayerSim();
    s.knockdown(0);
    drive(s, 0.3, { shelter: true });
    assertEq(s.state, 'knocked', 'holding C while down does not hijack the knockdown');
  });

  t.test('shelter: the wind barely moves you while braced', () => {
    const push = (input) => {
      const p = new PlayerSim();
      drive(p, 30, input, windX(2));                       // learn a calm baseline
      const x0 = p.pos.x;
      drive(p, 1.2, input, windX(24), 30);
      return Math.abs(p.pos.x - x0);
    };
    assertLess(push({ shelter: true }), push({}) * 0.5, 'bracing must cut the shove hard');
  });

  // ---------------------------------------------------------------- stumble
  t.test('stumble: a gust below the knockdown bar still breaks your stride', () => {
    const s = new PlayerSim();
    drive(s, 30, {}, windX(3));                            // calm baseline
    drive(s, 0.4, {}, windX(3 + TUNE.stumbleGust + 4), 30);
    assertEq(s.state, 'stumble', 'gust over stumbleGust but under knockWind');
    assert(s.busy, 'stumble is locked');
    drive(s, 1.0, {}, windX(3), 31);
    assertEq(s.state, 'idle', 'and it drains on its own');
  });

  t.test('stumble: one gust hold must not stumble you twice', () => {
    const s = new PlayerSim();
    drive(s, 30, {}, windX(3));
    let stumbles = 0;
    const before = s.events.length;
    drive(s, 2.5, {}, windX(3 + TUNE.stumbleGust + 4), 30);   // a full ~1.7 s hold and then some
    for (const e of s.events.slice(before)) if (e.type === 'state' && e.state === 'stumble') stumbles++;
    assertEq(stumbles, 1, 'stumbleCooldown makes it punctuation, not a stutter');
  });

  t.test('stumble: bracing means you keep your feet', () => {
    const s = new PlayerSim();
    drive(s, 30, { shelter: true }, windX(3));
    drive(s, 0.5, { shelter: true }, windX(3 + TUNE.stumbleGust + 4), 30);
    assertEq(s.state, 'shelter', 'braced, the gust does not stumble you');
  });

  // ---------------------------------------------------------------- tuned against the REAL storms
  // These are the guard rails the pre-merge tuning didn't have. Every threshold below is only
  // meaningful relative to the storm JSON it fires on, so assert against the JSON.
  t.test('storm_02: every player threshold is actually REACHABLE in the real storm', () => {
    const p = stormProfile(wild, undefined);
    assert(p.maxGust > TUNE.stumbleGust,
      `StumbleBack is dead code: storm_02 gusts peak at ${p.maxGust.toFixed(1)} m/s over baseline, `
      + `but stumbleGust is ${TUNE.stumbleGust}. Lower it or ask Lane C for angrier gusts.`);
    assert(p.maxGust > TUNE.shoveGustMin, `gust shove unreachable: peak ${p.maxGust.toFixed(1)}`);
    assert(p.maxWind > TUNE.knockWind,
      `knockdown unreachable: storm_02 peaks at ${p.maxWind.toFixed(1)} m/s, knockWind is ${TUNE.knockWind}`);
  });

  t.test('storm_02: reads as shoved → stumbling → floored, in that order of frequency', () => {
    const p = stormProfile(wild, undefined);
    assert(p.stumbles >= 2, `a wild night should break your stride more than twice, got ${p.stumbles}`);
    assert(p.knocks >= 1, `and floor you at least once, got ${p.knocks}`);
    assert(p.stumbles > p.knocks,
      `stumble is the beat and knockdown the punchline — got ${p.stumbles} stumbles vs ${p.knocks} knocks`);
    assert(p.shovedFor > 10, `you should feel pushed for a real slice of the storm, got ${p.shovedFor.toFixed(1)}s`);
    assertLess(p.knocks, 8, `${p.knocks} knockdowns in 90 s is unplayable, not dramatic`);
  });

  t.test('storm_01: a calm day leaves you completely alone', () => {
    const p = stormProfile(calm, undefined);
    assertEq(p.stumbles, 0, 'no stumbles on a gentle day');
    assertEq(p.knocks, 0, 'no knockdowns on a gentle day');
    assertLess(p.shovedFor, 1, 'and essentially no shove');
  });

  t.test('storm_02: bracing is what makes the worst of it survivable', () => {
    const exposed = new PlayerSim({ start: { x: 0, y: 0, z: 4 } });
    const braced = new PlayerSim({ start: { x: 0, y: 0, z: 4 } });
    let exposedKnocks = 0, bracedKnocks = 0;
    fixedLoop(90, DT, (dt, tt) => {
      exposed.step(dt, tt, {}, wild);
      braced.step(dt, tt, { shelter: true }, wild);
      for (const e of exposed.events) if (e.state === 'knocked') exposedKnocks++;
      for (const e of braced.events) if (e.state === 'knocked') bracedKnocks++;
      exposed.events.length = 0; braced.events.length = 0;
    });
    assert(exposedKnocks > 0, 'storm_02 floors you if you just stand in it');
    assertLess(bracedKnocks, exposedKnocks, 'and bracing through it is strictly better');
  });

  // ---------------------------------------------------------------- the ladder (decision 12)
  // A fake ladder standing in for ladder.js's THREE half: same shape, no GLB, no scene. The real
  // one is verified by hand in the game; these pin the legs of the state machine.
  const fakeLadder = (opts = {}) => {
    const st = { placedAt: opts.placedAt || null, carried: false };
    return {
      needsLadder: (a) => !!a && a.type === 'house',
      workY: () => 2.35,
      // height only, mirroring the real ladder.js — see the note there on why testing for 'atTop'
      // here makes the repair cancel its own hold
      isWorking: (id) => st.placedAt === id && !!opts.player && opts.player.climbY > 2.2,
      servedAnchor: () => null,
      get placedAt() { return st.placedAt; },
      _place: (id) => { st.placedAt = id; },
      update() {}, dispose() {},
    };
  };

  t.test('ladder: climb is code-driven and lands in a work stance', () => {
    const s = new PlayerSim();
    assertEq(s.climbY, 0, 'starts on the ground');
    s.climbTo(2.35);
    assertEq(s.state, 'climb', 'climbing');
    assert(s.busy, 'you cannot be interrupted mid-rung');
    assertEq(clipFor(s), 'ClimbLadder', 'and ClimbLadder plays');
    drive(s, 0.5);
    assert(s.climbY > 0.3 && s.climbY < 2.35, `partway up, got ${s.climbY.toFixed(2)}`);
    drive(s, 3);
    assertEq(s.state, 'atTop', 'arrives in the work stance');
    assertClose(s.climbY, 2.35, 1e-6, 'at the top rung');
    assert(!s.busy, 'atTop must NOT be busy — the whole point is that hold-E works up there');
  });

  t.test('ladder: the fascia is out of reach from the ground and in reach from the top', () => {
    const s = new PlayerSim();
    const FASCIA_Y = 2.48;                       // measured in the real yard
    assertLess(s.reachY, FASCIA_Y, 'standing on the ground, a 1.72 m person cannot reach the bracket');
    s.climbTo(2.35); drive(s, 4);
    assert(s.reachY >= FASCIA_Y, `up the ladder they can, reach=${s.reachY.toFixed(2)}`);
  });

  t.test('ladder: you cannot walk while you are on it', () => {
    const s = new PlayerSim();
    s.climbTo(2.35); drive(s, 4);
    assertEq(s.state, 'atTop');
    const x0 = s.pos.x, z0 = s.pos.z;
    drive(s, 1.5, { x: 1, z: 1, run: true, camYaw: 0 });
    assertClose(s.pos.x, x0, 1e-9, 'WASD does not walk you off a ladder');
    assertClose(s.pos.z, z0, 1e-9);
    assertEq(s.state, 'atTop', 'and you stay in the work stance');
  });

  t.test('ladder: descending returns you to the ground and frees you', () => {
    const s = new PlayerSim();
    s.climbTo(2.35); drive(s, 4);
    s.climbTo(0);
    assertEq(s.state, 'climb', 'going down is the same clip');
    drive(s, 4);
    assertEq(s.state, 'idle', 'back on your feet');
    assertEq(s.climbY, 0);
    drive(s, 1, { x: 0, z: 1, camYaw: 0 });
    assertEq(s.state, 'walk', 'and walking again');
  });

  t.test('ladder: you cannot brace up there — both hands are on the rungs', () => {
    const s = new PlayerSim();
    s.climbTo(2.35); drive(s, 4);
    // a wind under even the ladder's lowered bar, so this isolates the brace refusal from the fall
    drive(s, 1, { shelter: true }, windX(TUNE.knockWind * TUNE.ladderKnockMult - 4));
    assertEq(s.state, 'atTop', 'holding C on a ladder does nothing');
  });

  t.test('ladder: the wind is meaner at height, and being blown off is a FALL', () => {
    // a wind that is survivable standing must be able to take you off the ladder
    const between = TUNE.knockWind * TUNE.ladderKnockMult + 2;   // over the ladder bar, under the standing one
    assertLess(between, TUNE.knockWind, 'the test wind must be survivable on the ground');

    const ground = new PlayerSim();
    drive(ground, TUNE.knockSustain + 0.5, {}, windX(between));
    assertEq(ground.state, 'idle', 'on your feet this wind is nothing');

    const up = new PlayerSim();
    up.climbTo(2.35); drive(up, 4);
    up.carrying = 'spare';
    drive(up, TUNE.knockSustain + 0.3, {}, windX(between));
    assertEq(up.state, 'knocked', 'the same wind takes you off the ladder');
    assertEq(up.climbY, 0, 'you are on the ground now, not floating at height');
    assertClose(up.fellFrom, 2.35, 1e-6, 'and the fall height is recorded');
    assertEq(up.carrying, null, 'you dropped the spare on the way down');
    drive(up, 3);
    assertEq(up.state, 'idle', 'the ladder gets the normal get-up chain for free');
  });

  t.test('ladder: needsLadder is scoped to the fascia, not to everything above head height', () => {
    const L = fakeLadder();
    assert(L.needsLadder({ type: 'house', pos: { y: 2.48 } }), 'the fascia bracket needs it');
    assert(!L.needsLadder({ type: 'post', pos: { y: 3.95 } }),
      'a 4 m post does NOT — you tension it from a cleat at the base');
    assert(!L.needsLadder({ type: 'tree', pos: { y: 5.05 } }),
      'nor a tree limb — that is a strop you throw');
  });

  t.test('ladder: fascia re-rig is gated on being up it; post re-rig is not', () => {
    const p = new PlayerSim({ start: { x: 0, y: 0, z: 0 } });
    const L = fakeLadder({ player: p });
    const anchors = [{ id: 'h2', type: 'house', pos: { x: 0, y: 2.48, z: 0.9 } },
      { id: 'p1', type: 'post', pos: { x: 0, y: 3.95, z: 0 } }];
    const corners = [{ anchorId: 'h2', broken: true }, { anchorId: 'p1', broken: true }];
    let repaired = [];
    const it = new Interact();
    wireYardActions(it, {
      ladder: L,
      world: { anchors },
      sailRig: { corners, repair: (i) => repaired.push(i), trim: () => {},
        cornerPos: () => ({ x: 0, y: 0.4, z: 0 }) },
    });
    p.carrying = 'spare';

    // the POST corner: repairable from the ground, exactly as it was before the ladder existed
    p.pos.x = 0; p.pos.z = 0;
    fixedLoop(3.3, DT, (dt, tt) => it.step(dt, tt, p, true));
    assert(repaired.includes(1), 'post corner still re-rigs from the ground — the ladder changed nothing here');

    // the FASCIA corner: same spare, standing right under it, refused
    repaired = []; p.carrying = 'spare'; p.pos.x = 0; p.pos.z = 0.9;
    it.latched = false;
    const near = it.nearest(p);
    assert(!near || near.id !== 'rerig_0', 'standing under the bracket is not enough');
    fixedLoop(3.3, DT, (dt, tt) => it.step(dt, tt, p, true));
    assert(!repaired.includes(0), 'fascia re-rig refused from the ground');

    // plant the ladder and climb it → now it lands
    L._place('h2');
    p.climbTo(2.35); drive(p, 4);
    assertEq(p.state, 'atTop');
    p.carrying = 'spare';
    it.latched = false;
    fixedLoop(3.3, DT, (dt, tt) => it.step(dt, tt, p, true));
    assert(repaired.includes(0), 'up the ladder, the fascia re-rig lands');
    assertEq(p.carrying, null, 'and it ate the spare');
  });

  t.test('ladder: the scripted loop — carry, plant, fetch spare, climb, repair, descend', () => {
    const p = new PlayerSim({ start: { x: 0, y: 0, z: 0 } });
    const L = fakeLadder({ player: p });
    const anchors = [{ id: 'h2', type: 'house', pos: { x: 0, y: 2.48, z: 0.9 } }];
    const corners = [{ anchorId: 'h2', broken: true }];
    let repaired = false;
    const it = new Interact();
    wireYardActions(it, { ladder: L, world: { anchors },
      sailRig: { corners, repair: () => { repaired = true; }, trim: () => {},
        cornerPos: () => ({ x: 0, y: 0.4, z: 0 }) } });

    // hands-full: the ladder and the spare compete for the same pair of hands
    assertEq(p.pickUp('ladder'), true, 'pick the ladder up');
    assertEq(p.pickUp('spare'), false, 'you cannot also carry a spare — that is the two-trip cost');
    assertEq(p.drop(), 'ladder', 'put it down');

    // trip 2: the spare, then up
    assertEq(p.pickUp('spare'), true);
    L._place('h2');
    p.climbTo(L.workY()); drive(p, 4);
    assertEq(p.state, 'atTop', 'up the ladder with the spare');
    it.latched = false;
    fixedLoop(3.3, DT, (dt, tt) => it.step(dt, tt, p, true));
    assert(repaired, 'fascia repaired at height');
    assertEq(p.carrying, null, 'spare consumed');

    // and back down
    p.climbTo(0); drive(p, 4);
    assertEq(p.state, 'idle', 'down and free');
    assertEq(p.climbY, 0);
  });

  // ---------------------------------------------------------------- solids collision
  t.test('collision: solids stop you, and the pushout slides you along them', () => {
    // one box: the yard's north wall, x -8..8, z -16..-10, waist high
    const wall = { x0: -8, x1: 8, z0: -16, z1: -10, y0: 0, y1: 3 };
    const R = 0.3;
    const collide = (x, z, feetY, headY) => {
      if (wall.y1 <= feetY + 0.05 || wall.y0 >= headY) return { x, z };
      const cx = Math.min(Math.max(x, wall.x0), wall.x1);
      const cz = Math.min(Math.max(z, wall.z0), wall.z1);
      const dx = x - cx, dz = z - cz, d2 = dx * dx + dz * dz;
      if (d2 >= R * R || d2 <= 1e-10) return { x, z };
      const d = Math.sqrt(d2);
      return { x: cx + dx / d * R, z: cz + dz / d * R };
    };

    const s = new PlayerSim({ start: { x: 0, y: 0, z: -5 }, collide });
    drive(s, 6, { x: 0, z: 1, run: true, camYaw: 0 }, null);   // camYaw 0 → forward is -Z
    assert(s.pos.z >= -10 - 1e-6, `must not enter the wall, z=${s.pos.z.toFixed(3)}`);
    assertClose(s.pos.z, -10 + R, 0.02, 'stops exactly one body radius off the face');

    // Diagonal into a LONG wall: blocked north, but must still slide east. The wall has to outrun
    // the player here — against the 16 m one above, a 4 s diagonal sprint rounds its east end and
    // gets past, which is correct behaviour and not what this assert is about.
    const long = { ...wall, x0: -100, x1: 100 };
    const collideLong = (x, z, feetY, headY) => {
      if (long.y1 <= feetY + 0.05 || long.y0 >= headY) return { x, z };
      const cx = Math.min(Math.max(x, long.x0), long.x1);
      const cz = Math.min(Math.max(z, long.z0), long.z1);
      const dx = x - cx, dz = z - cz, d2 = dx * dx + dz * dz;
      if (d2 >= R * R || d2 <= 1e-10) return { x, z };
      const d = Math.sqrt(d2);
      return { x: cx + dx / d * R, z: cz + dz / d * R };
    };
    const g = new PlayerSim({ start: { x: 0, y: 0, z: -5 }, collide: collideLong });
    drive(g, 4, { x: 1, z: 1, run: true, camYaw: 0 }, null);
    assertClose(g.pos.z, -10 + R, 0.02, 'held off the wall');
    assert(g.pos.x > 2, `pushout must preserve the tangential slide, x=${g.pos.x.toFixed(2)}`);
  });

  t.test('collision: you can walk under an overhang (eaves are above your head)', () => {
    // the real roof: y 2.99..3.21, reaching 0.4 m further into the yard than the wall below it
    const collide = (x, z, feetY, headY) => {
      const y0 = 2.99, y1 = 3.21;
      if (y1 <= feetY + 0.05 || y0 >= headY) return { x, z };   // filtered out for a 1.72 m body
      return { x, z: Math.max(z, -9.6 + 0.3) };                 // would wall you off if it applied
    };
    const s = new PlayerSim({ start: { x: 0, y: 0, z: -5 }, collide, height: 1.72 });
    drive(s, 4, { x: 0, z: 1, run: true, camYaw: 0 }, null);   // camYaw 0 → forward is -Z
    assert(s.pos.z < -9, `a 3 m eave must not block a 1.7 m person, z=${s.pos.z.toFixed(2)}`);
  });

  // ---------------------------------------------------------------- determinism (PLAN3D §4)
  t.test('determinism: two identical 50 s runs produce byte-equal traces', () => {
    const trace = () => {
      const s = new PlayerSim();
      const out = [];
      fixedLoop(50, DT, (dt, tt) => {
        const w = { x: 6 + 24 * Math.max(0, Math.sin(tt * 0.7)), y: 0, z: 3 * Math.cos(tt * 0.31) };
        s.step(dt, tt, { x: Math.sin(tt), z: Math.cos(tt * 0.5), run: tt % 4 < 2, camYaw: tt * 0.2 }, w);
        out.push(`${s.state}|${s.pos.x.toFixed(9)}|${s.pos.z.toFixed(9)}|${s.pitch.toFixed(9)}`);
      });
      return out.join(';');
    };
    assertEq(trace(), trace(), 'same inputs must give the same trace');
  });

  // ---------------------------------------------------------------- interact
  const mk = () => {
    const sim = new PlayerSim({ start: { x: 0, y: 0, z: 0 } });
    const it = new Interact();
    let done = 0;
    it.register({ id: 'x', pos: { x: 0, y: 0, z: 0 }, radius: 1.5, holdSecs: 1, label: 'do it',
      onDone: () => { done++; } });
    return { sim, it, done: () => done };
  };

  t.test('interact: radius gates the action', () => {
    const { sim, it, done } = mk();
    sim.pos.x = 5;
    fixedLoop(2, DT, (dt, tt) => it.step(dt, tt, sim, true));
    assertEq(done(), 0, 'out of radius never fires');
    assert(!sim.busy, 'and never makes you busy');
  });

  t.test('interact: hold to completion fires once and hands the player back', () => {
    const { sim, it, done } = mk();
    fixedLoop(70 * DT, DT, (dt, tt) => it.step(dt, tt, sim, true));
    assertEq(done(), 1, 'fires once');
    assert(!sim.busy && sim.state === 'idle', 'player released');
    assert(it.events.some((e) => e.type === 'done' && e.id === 'x'), 'emits a done event');
  });

  t.test('interact: player is busy mid-hold, with a partial radial', () => {
    const { sim, it } = mk();
    fixedLoop(30 * DT, DT, (dt, tt) => it.step(dt, tt, sim, true));
    assert(sim.busy && sim.state === 'busy', 'busy while holding');
    assert(it.progress > 0.4 && it.progress < 0.6, `radial partway, got ${it.progress.toFixed(2)}`);
  });

  t.test('interact: one press, one action — a held key must not re-arm itself', () => {
    const { sim, it, done } = mk();
    fixedLoop(6.7, DT, (dt, tt) => it.step(dt, tt, sim, true));
    assertEq(done(), 1, 'holding E for 6.7 s over a 1 s action still fires once');
    it.step(DT, 7, sim, false);
    fixedLoop(70 * DT, DT, (dt, tt) => it.step(dt, 7 + tt, sim, true));
    assertEq(done(), 2, 'releasing re-arms it');
  });

  t.test('interact: releasing or walking away cancels the hold', () => {
    const a = mk();
    fixedLoop(30 * DT, DT, (dt, tt) => a.it.step(dt, tt, a.sim, true));
    a.it.step(DT, 0.5, a.sim, false);
    assertEq(a.it.progress, 0, 'release cancels');
    assert(!a.sim.busy && a.sim.state === 'idle', 'and frees the player');

    const b = mk();
    fixedLoop(30 * DT, DT, (dt, tt) => b.it.step(dt, tt, b.sim, true));
    b.sim.pos.x = 9;
    b.it.step(DT, 0.5, b.sim, true);
    assertEq(b.it.progress, 0, 'leaving the radius cancels');
    assertEq(b.done(), 0, 'without firing');
  });

  t.test('interact: a knockdown mid-hold aborts without stomping the knocked state', () => {
    const { sim, it, done } = mk();
    fixedLoop(30 * DT, DT, (dt, tt) => it.step(dt, tt, sim, true));
    sim.knockdown(0.5);
    it.step(DT, 0.51, sim, true);
    assertEq(it.progress, 0, 'hold aborted');
    assertEq(done(), 0, 'action did not fire');
    assertEq(sim.state, 'knocked', 'and the abort did not overwrite the knocked state');
  });

  t.test('interact: a hold survives the busy transition it causes', () => {
    // The bug this pins bit twice while building the ladder, and is invisible: canUse is re-checked
    // every frame to keep the hold alive, and starting the hold sets state='busy' — so any canUse
    // reading player.state goes false on frame one and cancels itself. Prompt looks dead, no error.
    const sim = new PlayerSim();
    const it = new Interact();
    let fired = 0;
    it.register({ id: 'ok', pos: { x: 0, y: 0, z: 0 }, radius: 2, holdSecs: 0.5,
      canUse: (p) => p.climbY < 0.02, onDone: () => { fired++; } });   // physical gate — fine
    fixedLoop(1, DT, (dt, tt) => it.step(dt, tt, sim, true));
    assertEq(fired, 1, 'a physically-gated action completes');

    const sim2 = new PlayerSim();
    const it2 = new Interact();
    let fired2 = 0;
    it2.register({ id: 'trap', pos: { x: 0, y: 0, z: 0 }, radius: 2, holdSecs: 0.5,
      canUse: (p) => p.state === 'idle', onDone: () => { fired2++; } });  // state gate — the trap
    fixedLoop(1, DT, (dt, tt) => it2.step(dt, tt, sim2, true));
    assertEq(fired2, 0,
      'a state-gated canUse cancels its own hold — documented on register(); gate on physical facts');
  });

  t.test('interact: canUse() gates on the carrying flag', () => {
    const sim = new PlayerSim();
    const it = new Interact();
    let fired = 0;
    it.register({ id: 'gated', pos: { x: 0, y: 0, z: 0 }, radius: 2, holdSecs: 0.5,
      canUse: (p) => !p.carrying, onDone: () => { fired++; } });
    sim.carrying = 'spare';
    fixedLoop(1, DT, (dt, tt) => it.step(dt, tt, sim, true));
    assertEq(fired, 0, 'hands full: gated');
    assert(!sim.busy, 'and never went busy');
    sim.carrying = null;
    fixedLoop(1, DT, (dt, tt) => it.step(dt, tt, sim, true));
    assertEq(fired, 1, 'fires once the gate opens');
  });

  // ---------------------------------------------------------------- hands-full + wiring
  t.test('hands-full rule: one item at a time', () => {
    const sim = new PlayerSim();
    assertEq(sim.pickUp('spare'), true, 'first item accepted');
    assertEq(sim.pickUp('wrench'), false, 'second refused');
    assertEq(sim.carrying, 'spare', 'still holding the first');
    assertEq(sim.drop(), 'spare', 'drop returns it');
    assertEq(sim.carrying, null, 'hands empty');
  });

  t.test('interact: the action names the verb the player plays', () => {
    const sim = new PlayerSim();
    const it = new Interact();
    it.register({ id: 'crank', pos: { x: 0, y: 0, z: 0 }, radius: 2, holdSecs: 1, clip: 'Crank' });
    fixedLoop(30 * DT, DT, (dt, tt) => it.step(dt, tt, sim, true));
    assertEq(sim.busyClip, 'Crank', 'busyClip is set for the hold');
    assertEq(clipFor(sim), 'Crank', 'and that is what plays');
    it.step(DT, 1, sim, false);
    assertEq(sim.busyClip, null, 'cancelling clears the verb');
    assertEq(clipFor(sim), 'Idle', 'back to the table');
  });

  t.test('interact: the verb is cleared on completion, so carry clips win afterwards', () => {
    const sim = new PlayerSim();
    const it = new Interact();
    it.register({ id: 'take', pos: { x: 0, y: 0, z: 0 }, radius: 2, holdSecs: 0.5, clip: 'PickUp',
      onDone: (p, tt) => p.pickUp('spare', tt) });
    fixedLoop(1, DT, (dt, tt) => it.step(dt, tt, sim, true));
    assertEq(sim.carrying, 'spare', 'picked it up');
    assertEq(sim.busyClip, null, 'verb cleared');
    assertEq(clipFor(sim), 'CarryIdle', 'and the player now reads as carrying');
  });

  t.test('wireYardActions: reads corners LIVE, so attach() cannot strand the targets', () => {
    // Lane A's warning: attach() REPLACES the corners array. Capturing the corner object at wire
    // time would leave these gated on a `broken` flag nothing updates ever again.
    const rig = {
      corners: [{ anchorId: 'p1', broken: true, pos: { x: 0, y: 2, z: 0 } }],
      repair: () => {}, trim: () => {},
      cornerPos: (i) => rig.corners[i].pos,
    };
    const it = new Interact();
    wireYardActions(it, { sailRig: rig });
    const p = new PlayerSim({ start: { x: 0, y: 0, z: 0 } });
    p.carrying = 'spare';
    assertEq(it.nearest(p).id, 'rerig_0', 'broken corner offers a re-rig');

    // now do what attach() does: swap the whole array for fresh objects
    rig.corners = [{ anchorId: 'p1', broken: false, pos: { x: 0, y: 2, z: 0 } }];
    assertEq(it.nearest(p).id, 'trim_0', 'the NEW corner is unbroken → trim, not re-rig');
    rig.corners = [{ anchorId: 'p1', broken: true, pos: { x: 4, y: 2, z: 4 } }];
    assertEq(it.nearest(p), null, 'and it followed the corner when it moved out of range');
  });

  t.test('wireYardActions: prompts track a moving (flogging) corner', () => {
    const corner = { anchorId: 'p1', broken: false, pos: { x: 0, y: 2, z: 0 } };
    const rig = { corners: [corner], repair: () => {}, trim: () => {}, cornerPos: (i) => rig.corners[i].pos };
    const it = new Interact();
    wireYardActions(it, { sailRig: rig });
    const p = new PlayerSim({ start: { x: 0, y: 0, z: 0 } });
    assertEq(it.nearest(p).id, 'trim_0', 'in range at the start');
    corner.pos = { x: 9, y: 2, z: 9 };                 // the corner blows away
    assertEq(it.nearest(p), null, 'prompt follows it out of range, not pinned to where it was');
  });

  t.test('wireYardActions: duck-types against a half-landed world', () => {
    const empty = new Interact();
    wireYardActions(empty, {});
    assertEq(empty.targets.size, 0, 'no sailRig yet (Lane B) -> no actions, no crash');

    const it = new Interact();
    const corners = [{ anchorId: 'p1', broken: true, pos: { x: 0, y: 2, z: 0 }, load: 0 }];
    let repaired = -1;
    wireYardActions(it, {
      sailRig: { corners, repair: (i) => { repaired = i; }, trim: () => {} },
      world: { shedTable: { pos: { x: 10, y: 0, z: 0 } } },
    });
    assertEq(it.targets.size, 3, 're-rig + trim + spare table');

    const p = new PlayerSim({ start: { x: 0, y: 0, z: 0 } });
    fixedLoop(3.3, DT, (dt, tt) => it.step(dt, tt, p, true));
    assertEq(repaired, -1, 're-rig refuses without a spare');
    p.carrying = 'spare';
    fixedLoop(3.3, DT, (dt, tt) => it.step(dt, 10 + tt, p, true));
    assertEq(repaired, 0, 're-rig fires with a spare');
    assertEq(p.carrying, null, 'and consumes it');
  });
}