import { useEffect, useRef, useState } from 'react'
import { useNavigate } from 'react-router-dom'
import { WEBHOOK_URL } from '../lib/webrtc'

export default function WatchRoom({ sessionId }) {
  const navigate      = useNavigate()
  const chatEndRef    = useRef(null)
  const [messages,    setMessages]  = useState([])
  const [connected,   setConnected] = useState(false)
  const [copied,      setCopied]    = useState(false)

  const watchUrl = `${window.location.origin}${window.location.pathname}#/watch/${sessionId}`

  useEffect(() => {
    chatEndRef.current?.scrollIntoView({ behavior: 'smooth' })
  }, [messages])

  useEffect(() => {
    const es = new EventSource(`${WEBHOOK_URL}/events?session=${sessionId}`)

    es.onopen = () => setConnected(true)

    es.onmessage = e => {
      try {
        const data = JSON.parse(e.data)
        const responses = data.responses || []
        const msgs = []

        // User transcript — non-streaming entry with out.user_input
        const userEntry = responses.find(r => !r.streaming && r.out?.user_input)
        if (userEntry) {
          const text = userEntry.out.user_input
            .replace(/<turn-visual-context>[\s\S]*?<\/turn-visual-context>/g, '')
            .replace(/<non-verbal-elements>[\s\S]*?<\/non-verbal-elements>/g, '')
            .trim()
          if (text) msgs.push({ role: 'user', text })
        }

        // AI text — main LLM only (prev_llm is audio filler, not transcript)
        const aiRaw = responses
          .filter(r => r.streaming && r.chunk && r.node === 'llm')
          .map(r => r.chunk)
          .join('')
        const aiText = aiRaw
          .split(/<\|speak\|>/)
          .map(seg => seg.replace(/<\|hangup\|>\S*/g, '').trim())
          .filter(Boolean)
          .join(' ')
          .trim()
        if (aiText) msgs.push({ role: 'ai', text: aiText })

        if (msgs.length) setMessages(prev => [...prev, ...msgs])
      } catch {}
    }

    es.onerror = () => setConnected(false)

    return () => es.close()
  }, [sessionId])

  function copyLink() {
    navigator.clipboard.writeText(watchUrl).then(() => {
      setCopied(true)
      setTimeout(() => setCopied(false), 2000)
    })
  }

  return (
    <div style={s.root}>
      {/* sidebar */}
      <aside style={s.sidebar}>
        <div style={s.sideTop}>
          <button style={s.back} onClick={() => navigate('/')}>← home</button>

          <p style={s.sideLabel}>watching session</p>
          <p style={s.sessionId}>{sessionId}</p>

          <div style={{ ...s.dot, background: connected ? 'var(--accent)' : 'var(--muted)', animation: connected ? 'blink .8s step-end infinite' : 'none' }} />
          <p style={s.connLabel}>{connected ? 'live' : 'waiting…'}</p>
        </div>

        <div style={s.sideDivider} />

        <div style={s.sideBottom}>
          <p style={s.shareSectionLabel}>Share this view</p>
          <p style={s.shareUrl}>{watchUrl}</p>
          <button
            style={{ ...s.copyBtn, ...(copied ? s.copyBtnDone : {}) }}
            onClick={copyLink}
          >
            {copied ? 'Copied!' : 'Copy link'}
          </button>
        </div>
      </aside>

      {/* main chat area */}
      <main style={s.main}>
        <header style={s.header}>
          <span style={s.headerLabel}>Live Transcript</span>
          {messages.length > 0 && (
            <span style={s.msgCount}>{messages.length} messages</span>
          )}
        </header>

        <div style={s.chatScroll}>
          {messages.length === 0 ? (
            <div style={s.emptyState}>
              <span style={s.emptyIcon}>◈</span>
              <p style={s.emptyTitle}>Waiting for the interview to begin</p>
              <p style={s.emptyHint}>Messages will appear here in real time as the conversation unfolds.</p>
            </div>
          ) : (
            messages.map((msg, i) => (
              <div key={i} style={{ ...s.msgRow, ...(msg.role === 'user' ? s.msgRowUser : s.msgRowAi) }}>
                <span style={{ ...s.role, color: msg.role === 'user' ? 'var(--user-ring)' : 'var(--ai-ring)' }}>
                  {msg.role === 'user' ? 'Candidate' : 'Interviewer'}
                </span>
                <div style={{ ...s.bubble, ...(msg.role === 'user' ? s.bubbleUser : s.bubbleAi) }}>
                  {msg.text}
                </div>
              </div>
            ))
          )}
          <div ref={chatEndRef} />
        </div>
      </main>
    </div>
  )
}

const s = {
  root: {
    height: '100vh',
    display: 'flex',
    flexDirection: 'row',
    overflow: 'hidden',
  },

  sidebar: {
    width: 220,
    flexShrink: 0,
    borderRight: '1px solid var(--border)',
    background: 'var(--surface)',
    display: 'flex',
    flexDirection: 'column',
    padding: '24px 18px',
    gap: 0,
  },
  sideTop: {
    display: 'flex',
    flexDirection: 'column',
    gap: 6,
  },
  back: {
    alignSelf: 'flex-start',
    fontFamily: 'var(--mono)',
    fontSize: 10,
    color: 'var(--muted)',
    background: 'none',
    border: 'none',
    cursor: 'pointer',
    letterSpacing: '.08em',
    padding: 0,
    marginBottom: 20,
  },
  sideLabel: {
    fontFamily: 'var(--mono)',
    fontSize: 8,
    letterSpacing: '.22em',
    textTransform: 'uppercase',
    color: 'var(--muted)',
  },
  sessionId: {
    fontFamily: 'var(--mono)',
    fontSize: 10,
    color: 'var(--text)',
    wordBreak: 'break-all',
    lineHeight: 1.5,
    marginBottom: 8,
  },
  dot: {
    width: 6,
    height: 6,
    borderRadius: '50%',
    flexShrink: 0,
  },
  connLabel: {
    fontFamily: 'var(--mono)',
    fontSize: 9,
    letterSpacing: '.18em',
    textTransform: 'uppercase',
    color: 'var(--muted)',
    marginTop: -4,
  },
  sideDivider: {
    height: 1,
    background: 'var(--border)',
    margin: '20px 0',
  },
  sideBottom: {
    display: 'flex',
    flexDirection: 'column',
    gap: 8,
  },
  shareSectionLabel: {
    fontFamily: 'var(--mono)',
    fontSize: 8,
    letterSpacing: '.22em',
    textTransform: 'uppercase',
    color: 'var(--muted)',
    marginBottom: 2,
  },
  shareUrl: {
    fontFamily: 'var(--mono)',
    fontSize: 9,
    color: 'var(--muted)',
    wordBreak: 'break-all',
    lineHeight: 1.5,
  },
  copyBtn: {
    fontFamily: 'var(--mono)',
    fontSize: 9,
    letterSpacing: '.12em',
    padding: '7px 0',
    borderRadius: 6,
    border: '1px solid var(--border2)',
    background: 'transparent',
    color: 'var(--text)',
    cursor: 'pointer',
    width: '100%',
    textAlign: 'center',
    transition: 'border-color .15s, color .15s',
    marginTop: 4,
  },
  copyBtnDone: {
    color: 'var(--accent)',
    borderColor: 'var(--accent)',
  },

  main: {
    flex: 1,
    display: 'flex',
    flexDirection: 'column',
    overflow: 'hidden',
  },
  header: {
    display: 'flex',
    alignItems: 'center',
    justifyContent: 'space-between',
    padding: '0 28px',
    height: 56,
    borderBottom: '1px solid var(--border)',
    flexShrink: 0,
  },
  headerLabel: {
    fontFamily: 'var(--mono)',
    fontSize: 11,
    letterSpacing: '.18em',
    textTransform: 'uppercase',
    color: 'var(--muted)',
  },
  msgCount: {
    fontFamily: 'var(--mono)',
    fontSize: 10,
    color: 'var(--muted)',
    background: 'var(--border2)',
    padding: '2px 8px',
    borderRadius: 10,
  },

  chatScroll: {
    flex: 1,
    overflowY: 'auto',
    padding: '24px 28px',
    display: 'flex',
    flexDirection: 'column',
    gap: 16,
  },

  emptyState: {
    display: 'flex',
    flexDirection: 'column',
    alignItems: 'center',
    justifyContent: 'center',
    gap: 12,
    flex: 1,
    paddingTop: 80,
  },
  emptyIcon: {
    fontSize: 32,
    color: 'var(--muted)',
    opacity: .4,
  },
  emptyTitle: {
    fontFamily: 'var(--sans)',
    fontSize: 15,
    fontWeight: 600,
    color: 'var(--text)',
    opacity: .6,
  },
  emptyHint: {
    fontFamily: 'var(--mono)',
    fontSize: 11,
    color: 'var(--muted)',
    textAlign: 'center',
    maxWidth: 360,
    lineHeight: 1.6,
    letterSpacing: '.06em',
  },

  msgRow: {
    display: 'flex',
    flexDirection: 'column',
    gap: 5,
    maxWidth: 640,
  },
  msgRowUser: { alignSelf: 'flex-end', alignItems: 'flex-end' },
  msgRowAi:   { alignSelf: 'flex-start', alignItems: 'flex-start' },

  role: {
    fontFamily: 'var(--mono)',
    fontSize: 8,
    letterSpacing: '.2em',
    textTransform: 'uppercase',
  },
  bubble: {
    fontSize: 13,
    lineHeight: 1.6,
    padding: '10px 14px',
    borderRadius: 12,
    wordBreak: 'break-word',
  },
  bubbleUser: {
    background: 'rgba(200,240,96,.08)',
    border: '1px solid rgba(200,240,96,.18)',
    color: 'var(--text)',
    borderBottomRightRadius: 3,
  },
  bubbleAi: {
    background: 'var(--surface)',
    border: '1px solid var(--border2)',
    color: 'var(--text)',
    borderBottomLeftRadius: 3,
  },
}