import * as THREE from 'three';
import { buildSkeleton } from '../src/character/skeleton.js';
import { buildStick } from '../src/character/stick.js';
import {
  applyTiltAnimation,
  applyTiltClip,
  captureSkeletonKeyframe,
  clipAsModule,
  createTiltClip,
  deleteClipKeyframe,
  frameSpan,
  sanitizeTiltClip,
  sampleTiltStick,
  setClipKeyframe,
  smoothTiltClip,
} from '../src/anim/clip.js';
import { done, ok, section } from './harness.mjs';

section('Tilt clips capture and interpolate the native skeleton');
{
  const skel = buildSkeleton();
  const clip = createTiltClip({ name: 'test-motion', loop: false, shotSide: 'left' });
  skel.bones.upperArmL.quaternion.setFromAxisAngle(new THREE.Vector3(1, 0, 0), 0);
  setClipKeyframe(clip, captureSkeletonKeyframe(skel, 0));
  skel.bones.upperArmL.quaternion.setFromAxisAngle(new THREE.Vector3(1, 0, 0), Math.PI / 2);
  setClipKeyframe(clip, captureSkeletonKeyframe(skel, 1));

  skel.bones.upperArmL.quaternion.identity();
  ok(applyTiltClip(skel, clip, 0.5), 'a populated clip applies');
  const angle = 2 * Math.acos(skel.bones.upperArmL.quaternion.w);
  ok(Math.abs(angle - Math.PI / 4) < 1e-5, 'quaternions slerp halfway');
  ok(frameSpan(clip, 2).a.time === 1, 'non-looping clips clamp at the end');
  ok(sanitizeTiltClip(clip).shotSide === 'left', 'clip preserves its authored stick socket side');
}

section('clip validation, replacement, smoothing, and export');
{
  const skel = buildSkeleton();
  const clip = createTiltClip({ name: 'hip check' });
  setClipKeyframe(clip, captureSkeletonKeyframe(skel, 0));
  setClipKeyframe(clip, captureSkeletonKeyframe(skel, 0));
  ok(clip.keyframes.length === 1, 'setting the same time replaces a key');
  setClipKeyframe(clip, captureSkeletonKeyframe(skel, 0.5));
  setClipKeyframe(clip, captureSkeletonKeyframe(skel, 1));
  smoothTiltClip(clip);
  const copy = sanitizeTiltClip(JSON.parse(JSON.stringify(clip)));
  ok(copy.keyframes.length === 3 && copy.rig === 'tilt-23', 'serialized clips validate');
  const module = clipAsModule(copy);
  ok(module.includes('export const hip_check') && module.includes('applyTiltAnimation'), 'module export is drop-in runtime JavaScript');
  ok(deleteClipKeyframe(copy, 0.5) && copy.keyframes.length === 2, 'keys can be deleted');
}

section('stick landmarks survive storage and interpolate with the pose');
{
  const skel = buildSkeleton();
  const clip = createTiltClip({ loop: false });
  const a = captureSkeletonKeyframe(skel, 0);
  a.stick = { butt: [0.4, 0.2], grip: [0.45, 0.4], blade: [0.5, 0.8], target: [-0.2, 0.03, 0.6], roll: 0, confidence: 0.8 };
  const b = captureSkeletonKeyframe(skel, 1);
  b.stick = { butt: [0.6, 0.2], grip: [0.6, 0.4], blade: [0.8, 0.8], target: [0.4, 0.2, 1.0], roll: 0.4, confidence: 1 };
  setClipKeyframe(clip, a);
  setClipKeyframe(clip, b);
  const stick = sampleTiltStick(clip, 0.5);
  ok(Math.abs(stick.blade[0] - 0.65) < 1e-6, 'blade landmark interpolates');
  ok(Math.abs(stick.target[0] - 0.1) < 1e-6, 'rig-local blade target interpolates');
  ok(Number.isFinite(stick.angle), 'legacy butt/blade marks derive a stable shaft angle');
  ok(sanitizeTiltClip(JSON.parse(JSON.stringify(clip))).keyframes[0].stick.confidence === 0.8, 'stick metadata serializes');
}

section('applied stick guides constrain the 3D shaft through both hands');
{
  const skel = buildSkeleton();
  const mover = new THREE.Group();
  mover.add(skel.rootBone);
  const stick = buildStick(null, null, 0);
  stick.attachTo(skel.bones.handR);
  const clip = createTiltClip({ loop: false });
  const frame = captureSkeletonKeyframe(skel, 0);
  frame.stick = {
    butt: [0.2, 0.2], grip: [0.3, 0.3], blade: [0.8, 0.8],
    target: [0, 0, 0], angle: 0.5, roll: 0.2, alignHands: true, confidence: 1,
  };
  setClipKeyframe(clip, frame);
  const skater = { skelData: skel, mover, stick };
  ok(applyTiltAnimation(skater, clip, 0), 'two-hand guide applies');

  const shaftA = new THREE.Vector3();
  const shaftB = new THREE.Vector3();
  const lowerHand = skel.bones.handL.getWorldPosition(new THREE.Vector3());
  stick.shaftSegment(shaftA, shaftB);
  const shaft = shaftB.clone().sub(shaftA);
  const t = THREE.MathUtils.clamp(lowerHand.clone().sub(shaftA).dot(shaft) / shaft.lengthSq(), 0, 1);
  const closest = shaftA.clone().addScaledVector(shaft, t);
  ok(shaftA.distanceTo(skel.bones.handR.getWorldPosition(new THREE.Vector3())) < 1e-6, 'shaft starts at the socket hand');
  ok(closest.distanceTo(lowerHand) < 1e-6, 'shaft crosses the lower hand in depth as well as screen space');
  ok(sanitizeTiltClip(JSON.parse(JSON.stringify(clip))).keyframes[0].stick.alignHands, 'two-hand constraint survives save/load');
}

section('equivalent stick-line directions do not bake a false half-turn');
{
  const skel = buildSkeleton();
  const clip = createTiltClip({ loop: false });
  for (const [time, angle] of [[0, 0.2], [0.5, Math.PI - 0.1], [1, 0.3]]) {
    const frame = captureSkeletonKeyframe(skel, time);
    frame.stick = {
      butt: [0.2, 0.2], grip: [0.3, 0.3], blade: [0.8, 0.8],
      target: [0, 0, 0], angle, roll: 0, confidence: 1,
    };
    setClipKeyframe(clip, frame);
  }
  const clean = sanitizeTiltClip(clip);
  const delta = Math.abs(clean.keyframes[1].stick.angle - clean.keyframes[0].stick.angle);
  ok(delta < Math.PI / 2, 'a PI-flipped detector result stays on the nearest shaft-line branch');
}

section('stick playback follows the actual socket bone');
{
  const skel = buildSkeleton();
  const mover = new THREE.Group();
  mover.add(skel.rootBone);
  const stickGroup = new THREE.Group();
  skel.bones.handL.add(stickGroup);
  const clip = createTiltClip({ loop: false, shotSide: 'left' });
  const frame = captureSkeletonKeyframe(skel, 0);
  frame.stick = {
    butt: [0.2, 0.2], grip: [0.3, 0.3], blade: [0.8, 0.8],
    target: [0, 0, 0], angle: -0.4, roll: 0, confidence: 1,
  };
  setClipKeyframe(clip, frame);
  let actualHand = null;
  const skater = {
    skelData: skel,
    mover,
    stick: {
      group: stickGroup,
      aimAt(_target, hand) { actualHand = hand.clone(); },
    },
  };
  applyTiltAnimation(skater, clip, 0);
  const expectedHand = skel.bones.handL.getWorldPosition(new THREE.Vector3());
  ok(actualHand?.distanceTo(expectedHand) < 1e-6, 'left socket playback anchors at handL instead of handR');
}

done('animation clip');