import { describe, it, expect } from 'vitest'
import { AnimationState } from '../src/anim-state.js'
import { makeClipLib } from './fixtures.js'

describe('AnimationState 多轨道状态机', () => {
  it('多轨道后写覆盖互不串扰（验收 3）', () => {
    const s = new AnimationState(makeClipLib())
    s.setAnimation('lower_body', 'leg.walk', { mix: 0 })
    s.setAnimation('head', 'head.talk_shake', { mix: 0 })
    s.setAnimation('arm_r', 'arm_r.point_right', { mix: 0 })
    s.update(150) // 推进
    const off = s.sampleBones()
    // 腿骨带到增量
    expect(off.thigh_l).toBeDefined()
    expect(off.thigh_r).toBeDefined()
    // 头骨带到增量
    expect(off.head).toBeDefined()
    // 右臂骨带到 point_right 增量
    expect(off.upper_arm_r.drot).toBeCloseTo(90, 6)
    // 互不串扰：head track 不写腿骨；lower_body 不写头骨——各自只在自己集合里
    // upper_arm_r 的增量来自 arm_r，不被 head/leg 覆盖
    expect(off.upper_arm_r).toBeDefined()
  })

  it('交叉淡入中点混合 ≈0.5（验收 4）', () => {
    const s = new AnimationState(makeClipLib())
    // 从 point_right(drot=90) 切到 down(drot=0)，mix=160
    s.setAnimation('arm_r', 'arm_r.point_right', { mix: 0 })
    s.update(10)
    s.setAnimation('arm_r', 'arm_r.down', { mix: 160 })
    s.update(80) // t=80ms，权重≈0.5
    const off = s.sampleBones()
    // 新 clip(down=0) 与旧 clip(point_right=90) 混合，权重 0.5 → ≈45
    expect(off.upper_arm_r.drot).toBeGreaterThan(30)
    expect(off.upper_arm_r.drot).toBeLessThan(60)
  })

  it('mix 走完只剩新 clip（验收 4）', () => {
    const s = new AnimationState(makeClipLib())
    s.setAnimation('arm_r', 'arm_r.point_right', { mix: 0 })
    s.update(10)
    s.setAnimation('arm_r', 'arm_r.down', { mix: 160 })
    s.update(200) // 过 mix
    const off = s.sampleBones()
    expect(off.upper_arm_r.drot).toBeCloseTo(0, 6)
    expect(s.tracks.arm_r.prevClipId).toBeNull()
  })

  it('oneshot 超时回落 fallback（验收 5）', () => {
    const s = new AnimationState(makeClipLib())
    s.setAnimation('head', 'head.nod', { mix: 0, fallback: 'head.idle' })
    expect(s.tracks.head.clipId).toBe('head.nod')
    s.update(500) // head.nod duration=400，过时
    expect(s.tracks.head.clipId).toBe('head.idle')
  })

  it('reset 回各轨道默认 clip', () => {
    const s = new AnimationState(makeClipLib())
    s.setAnimation('lower_body', 'leg.walk', { mix: 0 })
    s.reset()
    expect(s.tracks.lower_body.clipId).toBe('leg.stand_together')
    expect(s.tracks.head.clipId).toBe('head.idle')
  })

  it('未知 clip / 已在播不打断', () => {
    const s = new AnimationState(makeClipLib())
    s.setAnimation('head', 'no.such.clip')
    expect(s.tracks.head.clipId).toBe('head.idle') // 未变
    const before = s.tracks.head.elapsed
    s.update(100)
    s.setAnimation('head', 'head.idle') // 已在播且无过渡 → 不打断（不归零 elapsed）
    expect(s.tracks.head.elapsed).toBeGreaterThanOrEqual(before)
  })
})