import { create } from 'zustand'
import type { Podcast } from '@/types'
import { isExternalUrl, getEmbedInfo } from '@/lib/embed'

// Hidden iframe manager for external content
let hiddenIframe: HTMLIFrameElement | null = null

function destroyIframe() {
  if (hiddenIframe) {
    hiddenIframe.remove()
    hiddenIframe = null
  }
}

function createHiddenIframe(embedUrl: string) {
  destroyIframe()
  const iframe = document.createElement('iframe')
  iframe.src = embedUrl
  iframe.allow = 'autoplay; encrypted-media'
  iframe.style.cssText = 'position:fixed;width:1px;height:1px;left:-10px;top:-10px;opacity:0;pointer-events:none;'
  document.body.appendChild(iframe)
  hiddenIframe = iframe
}

interface PlayerState {
  current: Podcast | null
  isPlaying: boolean
  isExternal: boolean
  progress: number
  duration: number
  volume: number
  audio: HTMLAudioElement | null

  play: (podcast: Podcast) => void
  toggle: () => void
  pause: () => void
  seek: (time: number) => void
  setVolume: (vol: number) => void
  setProgress: (progress: number) => void
  setDuration: (duration: number) => void
}

export const usePlayerStore = create<PlayerState>((set, get) => ({
  current: null,
  isPlaying: false,
  isExternal: false,
  progress: 0,
  duration: 0,
  volume: 0.8,
  audio: null,

  play: (podcast) => {
    const { audio, current } = get()
    const external = isExternalUrl(podcast.audio_url)

    // Resume same podcast
    if (current?.id === podcast.id) {
      if (external) {
        const embed = getEmbedInfo(podcast.audio_url)
        if (embed) createHiddenIframe(embed.embedUrl)
        set({ isPlaying: true })
        return
      }
      if (audio) {
        audio.play()
        set({ isPlaying: true })
        return
      }
    }

    // Stop previous
    if (audio) {
      audio.pause()
      audio.removeAttribute('src')
    }
    destroyIframe()

    // External: play via hidden iframe
    if (external) {
      const embed = getEmbedInfo(podcast.audio_url)
      if (embed) createHiddenIframe(embed.embedUrl)
      set({ audio: null, current: podcast, isPlaying: true, isExternal: true, progress: 0, duration: podcast.duration_seconds || 0 })
      return
    }

    const newAudio = new Audio(podcast.audio_url)
    newAudio.volume = get().volume

    newAudio.addEventListener('timeupdate', () => {
      set({ progress: newAudio.currentTime })
    })
    newAudio.addEventListener('loadedmetadata', () => {
      set({ duration: newAudio.duration })
    })
    newAudio.addEventListener('ended', () => {
      set({ isPlaying: false, progress: 0 })
    })

    newAudio.play()
    set({ audio: newAudio, current: podcast, isPlaying: true, isExternal: false, progress: 0 })
  },

  toggle: () => {
    const { audio, isPlaying, isExternal, current } = get()
    if (isExternal) {
      if (isPlaying) {
        destroyIframe()
      } else {
        const embed = current ? getEmbedInfo(current.audio_url) : null
        if (embed) createHiddenIframe(embed.embedUrl)
      }
      set({ isPlaying: !isPlaying })
      return
    }
    if (!audio) return
    if (isPlaying) {
      audio.pause()
    } else {
      audio.play()
    }
    set({ isPlaying: !isPlaying })
  },

  pause: () => {
    const { isExternal } = get()
    if (isExternal) destroyIframe()
    get().audio?.pause()
    set({ isPlaying: false })
  },

  seek: (time) => {
    const { audio } = get()
    if (!audio) return
    audio.currentTime = time
    set({ progress: time })
  },

  setVolume: (vol) => {
    const { audio } = get()
    if (audio) audio.volume = vol
    set({ volume: vol })
  },

  setProgress: (progress) => set({ progress }),
  setDuration: (duration) => set({ duration }),
}))