import { create } from 'zustand'
import { PLAYBACK_SPEEDS } from '../types/areaSearch.types'

interface AnimationState {
  isPlaying: boolean
  currentTime: number         // Unix epoch ms
  startTime: number
  endTime: number
  playbackSpeed: number       // 1x ~ 1000x
  loop: boolean
  animationFrameId: number | null
  lastFrameTime: number

  play: () => void
  pause: () => void
  stop: () => void
  setPlaybackSpeed: (speed: number) => void
  setCurrentTime: (time: number) => void
  setProgressByRatio: (ratio: number) => void
  setTimeRange: (start: number, end: number) => void
  toggleLoop: () => void
  getProgress: () => number   // 0~100
  reset: () => void
}

export { PLAYBACK_SPEEDS }

export const useAreaAnimationStore = create<AnimationState>((set, get) => ({
  isPlaying: false,
  currentTime: 0,
  startTime: 0,
  endTime: 0,
  playbackSpeed: 100,
  loop: false,
  animationFrameId: null,
  lastFrameTime: 0,

  play: () => {
    const state = get()
    if (state.isPlaying) return
    if (state.startTime >= state.endTime) return

    if (state.currentTime >= state.endTime) {
      set({ currentTime: state.startTime })
    }

    set({ isPlaying: true, lastFrameTime: performance.now() })

    const animate = (timestamp: number) => {
      const s = get()
      if (!s.isPlaying) return

      const deltaMs = timestamp - s.lastFrameTime
      const increment = (deltaMs / 1000) * s.playbackSpeed * 1000
      let newTime = s.currentTime + increment

      if (newTime > s.endTime) {
        if (s.loop) {
          newTime = s.startTime
        } else {
          set({ isPlaying: false, currentTime: s.endTime, animationFrameId: null })
          return
        }
      }

      set({ currentTime: newTime, lastFrameTime: timestamp })
      const frameId = requestAnimationFrame(animate)
      set({ animationFrameId: frameId })
    }

    const frameId = requestAnimationFrame(animate)
    set({ animationFrameId: frameId })
  },

  pause: () => {
    const { animationFrameId } = get()
    if (animationFrameId !== null) cancelAnimationFrame(animationFrameId)
    set({ isPlaying: false, animationFrameId: null })
  },

  stop: () => {
    const { animationFrameId, startTime } = get()
    if (animationFrameId !== null) cancelAnimationFrame(animationFrameId)
    set({ isPlaying: false, animationFrameId: null, currentTime: startTime })
  },

  setPlaybackSpeed: (speed) => set({ playbackSpeed: speed }),

  setCurrentTime: (time) => set({ currentTime: time }),

  setProgressByRatio: (ratio) => {
    const { startTime, endTime } = get()
    const time = startTime + (endTime - startTime) * Math.max(0, Math.min(1, ratio))
    set({ currentTime: time })
  },

  setTimeRange: (start, end) => set({ startTime: start, endTime: end, currentTime: start }),

  toggleLoop: () => set((s) => ({ loop: !s.loop })),

  getProgress: () => {
    const { currentTime, startTime, endTime } = get()
    if (endTime <= startTime) return 0
    return ((currentTime - startTime) / (endTime - startTime)) * 100
  },

  reset: () => {
    const { animationFrameId } = get()
    if (animationFrameId !== null) cancelAnimationFrame(animationFrameId)
    set({
      isPlaying: false,
      currentTime: 0,
      startTime: 0,
      endTime: 0,
      playbackSpeed: 100,
      loop: false,
      animationFrameId: null,
      lastFrameTime: 0,
    })
  },
}))