import React, { useEffect, useRef, useState } from 'react'
import styles from './PreJoin.module.css'
import { ControlBar, ControlButton, MicrophoneMeter, modifierKeyLabel, isMacPlatform } from 'avanza-ui'
import { FiMic, FiVideo, FiSettings } from 'react-icons/fi'

type Props = {
  roomName?: string
  onProceed: () => void
  onCancel?: () => void
  serverUrl?: string
  token?: string
}

export default function PreJoin({ roomName, onProceed, onCancel }: Props) {
  const videoRef = useRef<HTMLVideoElement | null>(null)
  const [name, setName] = useState(() => {
    try { return localStorage.getItem('avanzacast_user') || '' } catch { return '' }
  })
  const [micEnabled, setMicEnabled] = useState(true)
  const [camEnabled, setCamEnabled] = useState(true)
  const [error, setError] = useState<string | null>(null)
  const [isChecking, setIsChecking] = useState(false)
  // checkbox state is local only; do NOT persist skip preference so PreJoin always appears
  const [skipNextTime, setSkipNextTime] = useState<boolean>(false)
  // keep preview stream active for meter and preview
  const [previewStream, setPreviewStream] = useState<MediaStream | null>(null)

  // Use shared platform utils
  const isMac = isMacPlatform()
  const modLabel = modifierKeyLabel()
  const micHint = `${modLabel.display} + D`
  const camHint = `${modLabel.display} + E`

  useEffect(() => {
    // ensure any old skip flag does not affect behavior: remove legacy key
    try { localStorage.removeItem('broadcast:skipPrejoin') } catch (e) {}
    // request preview stream whenever toggles change
    let mounted = true
    let localStream: MediaStream | null = null
    ;(async () => {
      try {
        if (!navigator?.mediaDevices?.getUserMedia) return
        localStream = await navigator.mediaDevices.getUserMedia({ audio: micEnabled, video: camEnabled })
        if (!mounted) {
          try { localStream.getTracks().forEach(t => t.stop()) } catch (e) {}
          return
        }
        setPreviewStream(localStream)
        if (videoRef.current) {
          videoRef.current.srcObject = localStream
          videoRef.current.play().catch(() => {})
        }
      } catch (e: any) {
        // ignore permission errors
      }
    })()

    // Keyboard shortcuts: toggle mic/camera. Support Ctrl on Windows/Linux and Meta (⌘) on macOS.
    const onKeyDown = (e: KeyboardEvent) => {
      // ignore when focused on input/textarea or when modifier keys conflict with browser shortcuts
      const active = document.activeElement;
      const tag = active && (active as HTMLElement).tagName;
      if (tag === 'INPUT' || tag === 'TEXTAREA' || (active as HTMLElement)?.isContentEditable) return;

      const mod = isMac ? e.metaKey : e.ctrlKey

      // Mod + D -> toggle mic
      if (mod && !e.shiftKey && (e.key === 'd' || e.key === 'D')) {
        e.preventDefault()
        setMicEnabled(v => !v)
      }

      // Mod + E -> toggle camera (requested)
      if (mod && !e.shiftKey && (e.key === 'e' || e.key === 'E')) {
        e.preventDefault()
        setCamEnabled(v => !v)
      }

      // Mod + Shift + C -> alternate camera shortcut (also supported)
      if ((e.ctrlKey || e.metaKey) && e.shiftKey && (e.key === 'c' || e.key === 'C')) {
        e.preventDefault()
        setCamEnabled(v => !v)
      }
    }
    window.addEventListener('keydown', onKeyDown)

    return () => {
      mounted = false
      if (localStream) {
        try { localStream.getTracks().forEach(t => t.stop()) } catch (e) {}
      }
      // clear previewStream state
      setPreviewStream(null)
      window.removeEventListener('keydown', onKeyDown)
    }
  }, [micEnabled, camEnabled])

  const handleProceed = async () => {
    setError(null)
    setIsChecking(true)
    try {
      // request permissions explicitly
      await navigator.mediaDevices.getUserMedia({ audio: micEnabled, video: camEnabled })
      // save name
      try { if (name) localStorage.setItem('avanzacast_user', name) } catch (e) {}
      // proceed to connect
      onProceed()
    } catch (e: any) {
      setError(e?.message || 'No se pudo acceder a la cámara/micrófono')
    } finally {
      setIsChecking(false)
    }
  }

  const toggleMic = async () => {
    setMicEnabled(v => !v)
  }

  const toggleCam = async () => {
    setCamEnabled(v => !v)
  }

  return (
    <div className={styles.prejoinContainer}>
      <div className={styles.card}>
        <div className={styles.header}>
          <div>Configura tu estudio</div>
          <div className={styles.note}>Entrar al estudio no iniciará automáticamente la transmisión.</div>
        </div>

        <div className={styles.contentRow}>
          <div className={styles.previewColumn}>
            <div className={styles.previewCard}>
              <video ref={videoRef} className={styles.videoEl} playsInline muted />
              <div className={styles.badge}>{name || 'Invitado'}</div>
              <div className={styles.micPanel}>
                <div className={styles.micPanelInner}>
                  <MicrophoneMeter level={previewStream ? 1 : 0} />
                  <div className={styles.micStatus}>{micEnabled ? 'El micrófono está funcionando' : 'Micrófono desactivado'}</div>
                </div>
              </div>
            </div>

            <div className={styles.controlsRow}>
              <ControlButton
                className={styles.controlButtonLocal}
                icon={<FiMic />}
                label={micEnabled ? 'Desactivar audio' : 'Activar audio'}
                active={micEnabled}
                danger={!micEnabled}
                layout="column"
                variant="studio"
                onClick={toggleMic}
                hint={micHint}
                size="md"
              />

              <ControlButton
                className={styles.controlButtonLocal}
                icon={<FiVideo />}
                label={camEnabled ? 'Detener cámara' : 'Iniciar cámara'}
                active={camEnabled}
                danger={!camEnabled}
                layout="column"
                variant="studio"
                onClick={toggleCam}
                hint={camHint}
                size="md"
              />

              <ControlButton
                className={styles.controlButtonLocal}
                icon={<FiSettings />}
                label={'Configuración'}
                active={true}
                layout="column"
                variant="studio"
                onClick={() => { /* abrir modal de settings si aplica */ }}
                size="md"
              />
            </div>

            {/* Leyenda de atajos: muestra las combinaciones detectadas (ej: ⌘ + D) */}
            <div className={styles.shortcutsLegend} aria-hidden="true">
              Atajos: <span className={styles.kbd}>{micHint}</span> mic · <span className={styles.kbd}>{camHint}</span> cámara
            </div>

          </div>

          <div className={styles.sideColumn}>
            {error && <div className={styles.error}>{error}</div>}

            <div className={styles.roomTitle}>Nombre para mostrar</div>
            <input className={styles.input} value={name} onChange={e => setName(e.target.value)} placeholder="Tu nombre" />

            <div className={styles.roomTitle}>Título (opcional)</div>
            <input className={styles.input} placeholder="p. ej.: Founder of Creativity Inc" />

            <div className={styles.checkboxRow}>
              <input id="skipNext" type="checkbox" checked={skipNextTime} onChange={e => setSkipNextTime(e.target.checked)} />
              <label htmlFor="skipNext">Omitir PreJoin la próxima vez</label>
            </div>

            <div className={styles.actions}>
              <button className={styles.cancelBtn} onClick={() => { onCancel?.() }}>Cancelar</button>
              <button className={styles.primaryBtn} onClick={handleProceed} disabled={isChecking}>{isChecking ? 'Comprobando...' : 'Entrar al estudio'}</button>
            </div>

          </div>
        </div>

      </div>
    </div>
  )
}