/**
 * 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 } 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';

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));

/** @param {import('../testkit.js').Suite} t */
export default function run(t) {
  // ---------------------------------------------------------------- state machine table
  t.test('state table: every state\'s clip exists in player_anims.glb', () => {
    const clips = new Set(['Idle', 'Walk', 'Run', 'Falling', 'CrouchToStand', 'Reaction']);
    for (const [name, st] of Object.entries(STATES)) {
      assert(clips.has(st.clip), `state ${name} wants missing clip ${st.clip}`);
    }
  });

  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');
  });

  // ---------------------------------------------------------------- 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: 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('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');
  });
}