/**
 * Debug Screen - Voice Call Testing with Detailed Logs
 *
 * All-in-one screen for testing Julia AI voice:
 * - Start/End call buttons
 * - Real-time logs of all LiveKit events
 * - Copy logs button
 */

import React, { useState, useEffect, useRef, useCallback } from 'react';
import {
  View,
  Text,
  StyleSheet,
  FlatList,
  TouchableOpacity,
  Platform,
  Share,
  AppState,
  AppStateStatus,
} from 'react-native';
import { SafeAreaView } from 'react-native-safe-area-context';
import { Ionicons } from '@expo/vector-icons';
import * as Clipboard from 'expo-clipboard';
import { activateKeepAwakeAsync, deactivateKeepAwake } from 'expo-keep-awake';
import type { Room as RoomType } from 'livekit-client';
import { AppColors, BorderRadius, FontSizes, Spacing } from '@/constants/theme';
import { getToken, VOICE_NAME } from '@/services/livekitService';

type LogEntry = {
  id: string;
  time: string;
  message: string;
  type: 'info' | 'success' | 'error' | 'event';
};

type CallState = 'idle' | 'connecting' | 'connected' | 'ending';

export default function DebugScreen() {
  const [logs, setLogs] = useState<LogEntry[]>([]);
  const [callState, setCallState] = useState<CallState>('idle');
  const [callDuration, setCallDuration] = useState(0);
  const flatListRef = useRef<FlatList>(null);
  const roomRef = useRef<RoomType | null>(null);
  const callStartTimeRef = useRef<number | null>(null);
  const appStateRef = useRef<AppStateStatus>(AppState.currentState);

  // Add log entry
  const log = useCallback((message: string, type: LogEntry['type'] = 'info') => {
    const time = new Date().toLocaleTimeString('en-US', { hour12: false, hour: '2-digit', minute: '2-digit', second: '2-digit' });
    const ms = String(new Date().getMilliseconds()).padStart(3, '0');
    setLogs(prev => [...prev, {
      id: `${Date.now()}-${Math.random()}`,
      time: `${time}.${ms}`,
      message,
      type,
    }]);
  }, []);

  // Clear logs
  const clearLogs = useCallback(() => {
    setLogs([]);
  }, []);

  // Copy logs to clipboard
  const copyLogs = useCallback(async () => {
    const text = logs.map(l => `[${l.time}] ${l.message}`).join('\n');
    await Clipboard.setStringAsync(text);
    log('Logs copied to clipboard!', 'success');
  }, [logs, log]);

  // Share logs
  const shareLogs = useCallback(async () => {
    const text = logs.map(l => `[${l.time}] ${l.message}`).join('\n');
    try {
      await Share.share({ message: text, title: 'Voice Debug Logs' });
    } catch (e) {
      log(`Share failed: ${e}`, 'error');
    }
  }, [logs, log]);

  // Auto-scroll to bottom
  useEffect(() => {
    if (logs.length > 0) {
      setTimeout(() => flatListRef.current?.scrollToEnd({ animated: true }), 100);
    }
  }, [logs]);

  // Call duration timer
  useEffect(() => {
    if (callState !== 'connected') return;
    const interval = setInterval(() => {
      if (callStartTimeRef.current) {
        setCallDuration(Math.floor((Date.now() - callStartTimeRef.current) / 1000));
      }
    }, 1000);
    return () => clearInterval(interval);
  }, [callState]);

  // Handle app background/foreground
  useEffect(() => {
    const subscription = AppState.addEventListener('change', (nextAppState) => {
      if (appStateRef.current.match(/inactive|background/) && nextAppState === 'active') {
        log('App returned to foreground', 'event');
      } else if (appStateRef.current === 'active' && nextAppState.match(/inactive|background/)) {
        log('App went to background - call continues', 'event');
      }
      appStateRef.current = nextAppState;
    });
    return () => subscription.remove();
  }, [log]);

  // Start call
  const startCall = useCallback(async () => {
    if (callState !== 'idle') return;

    clearLogs();
    setCallState('connecting');
    setCallDuration(0);
    callStartTimeRef.current = null;

    try {
      log('=== STARTING VOICE CALL ===', 'info');

      // Keep screen awake
      await activateKeepAwakeAsync('voiceCall').catch(() => {});
      log('Screen keep-awake activated', 'info');

      // Step 1: Register WebRTC globals
      log('Step 1: Importing @livekit/react-native...', 'info');
      const { registerGlobals, AudioSession } = await import('@livekit/react-native');

      if (typeof global.RTCPeerConnection === 'undefined') {
        log('Registering WebRTC globals...', 'info');
        registerGlobals();
        log('WebRTC globals registered', 'success');
      } else {
        log('WebRTC globals already registered', 'info');
      }

      // Step 2: Import livekit-client
      log('Step 2: Importing livekit-client...', 'info');
      const { Room, RoomEvent, ConnectionState, Track } = await import('livekit-client');
      log('livekit-client imported', 'success');

      // Step 3: Start iOS AudioSession
      if (Platform.OS === 'ios') {
        log('Step 3: Starting iOS AudioSession...', 'info');
        await AudioSession.startAudioSession();
        log('iOS AudioSession started', 'success');
      }

      // Step 4: Get token from server
      log('Step 4: Requesting token from server...', 'info');
      log(`Token server: wellnuo.smartlaunchhub.com/julia/token`, 'info');
      const result = await getToken(`user-${Date.now()}`);

      if (!result.success || !result.data) {
        throw new Error(result.error || 'Failed to get token');
      }

      const { token, wsUrl, roomName } = result.data;
      log(`Token received`, 'success');
      log(`Room: ${roomName}`, 'info');
      log(`WebSocket URL: ${wsUrl}`, 'info');

      // Step 5: Create room and setup listeners
      log('Step 5: Creating Room instance...', 'info');
      const room = new Room();
      roomRef.current = room;
      log('Room instance created', 'success');

      // Setup ALL event listeners
      log('Step 6: Setting up event listeners...', 'info');

      room.on(RoomEvent.ConnectionStateChanged, (state: any) => {
        log(`EVENT: ConnectionStateChanged → ${state}`, 'event');
        if (state === ConnectionState.Connected) {
          setCallState('connected');
          callStartTimeRef.current = Date.now();
        } else if (state === ConnectionState.Disconnected) {
          setCallState('idle');
        }
      });

      room.on(RoomEvent.Connected, () => {
        log('EVENT: Connected to room', 'success');
      });

      room.on(RoomEvent.Disconnected, (reason?: any) => {
        log(`EVENT: Disconnected. Reason: ${reason || 'unknown'}`, 'event');
      });

      room.on(RoomEvent.Reconnecting, () => {
        log('EVENT: Reconnecting...', 'event');
      });

      room.on(RoomEvent.Reconnected, () => {
        log('EVENT: Reconnected', 'success');
      });

      room.on(RoomEvent.ParticipantConnected, (participant: any) => {
        log(`EVENT: Participant connected: ${participant.identity}`, 'event');
      });

      room.on(RoomEvent.ParticipantDisconnected, (participant: any) => {
        log(`EVENT: Participant disconnected: ${participant.identity}`, 'event');
      });

      room.on(RoomEvent.TrackSubscribed, (track: any, publication: any, participant: any) => {
        log(`EVENT: Track subscribed: ${track.kind} from ${participant.identity}`, 'event');
        if (track.kind === Track.Kind.Audio) {
          log('Audio track from Julia AI - should hear voice now', 'success');
        }
      });

      room.on(RoomEvent.TrackUnsubscribed, (track: any, publication: any, participant: any) => {
        log(`EVENT: Track unsubscribed: ${track.kind} from ${participant.identity}`, 'event');
      });

      room.on(RoomEvent.TrackMuted, (publication: any, participant: any) => {
        log(`EVENT: Track muted by ${participant.identity}`, 'event');
      });

      room.on(RoomEvent.TrackUnmuted, (publication: any, participant: any) => {
        log(`EVENT: Track unmuted by ${participant.identity}`, 'event');
      });

      room.on(RoomEvent.ActiveSpeakersChanged, (speakers: any[]) => {
        if (speakers.length > 0) {
          log(`EVENT: Active speakers: ${speakers.map(s => s.identity).join(', ')}`, 'event');
        }
      });

      room.on(RoomEvent.DataReceived, (payload: any, participant: any) => {
        try {
          const data = JSON.parse(new TextDecoder().decode(payload));
          log(`EVENT: Data received: ${JSON.stringify(data).substring(0, 100)}`, 'event');
        } catch (e) {
          log(`EVENT: Data received (binary)`, 'event');
        }
      });

      room.on(RoomEvent.AudioPlaybackStatusChanged, () => {
        log(`EVENT: AudioPlaybackStatusChanged - canPlay: ${room.canPlaybackAudio}`, 'event');
      });

      room.on(RoomEvent.MediaDevicesError, (error: any) => {
        log(`EVENT: MediaDevicesError: ${error?.message || error}`, 'error');
      });

      room.on(RoomEvent.RoomMetadataChanged, (metadata: string) => {
        log(`EVENT: RoomMetadataChanged: ${metadata}`, 'event');
      });

      log('Event listeners set up', 'success');

      // Step 7: Connect to room
      log('Step 7: Connecting to LiveKit room...', 'info');
      await room.connect(wsUrl, token, { autoSubscribe: true });
      log('Connected to room', 'success');

      // Step 8: Enable microphone
      log('Step 8: Enabling microphone...', 'info');
      await room.localParticipant.setMicrophoneEnabled(true);
      log('Microphone enabled', 'success');

      log(`Local participant: ${room.localParticipant.identity}`, 'info');
      log('=== CALL ACTIVE ===', 'success');

    } catch (err: any) {
      log(`ERROR: ${err?.message || err}`, 'error');
      log(`Stack: ${err?.stack?.substring(0, 200) || 'no stack'}`, 'error');
      setCallState('idle');
      deactivateKeepAwake('voiceCall');
    }
  }, [callState, log, clearLogs]);

  // End call
  const endCall = useCallback(async () => {
    if (callState === 'idle') return;

    log('=== ENDING CALL ===', 'info');
    setCallState('ending');

    try {
      if (roomRef.current) {
        log('Disconnecting from room...', 'info');
        await roomRef.current.disconnect();
        roomRef.current = null;
        log('Disconnected from room', 'success');
      }

      if (Platform.OS === 'ios') {
        log('Stopping iOS AudioSession...', 'info');
        const { AudioSession } = await import('@livekit/react-native');
        await AudioSession.stopAudioSession();
        log('iOS AudioSession stopped', 'success');
      }

      deactivateKeepAwake('voiceCall');
      log('Screen keep-awake deactivated', 'info');

    } catch (err: any) {
      log(`Error during cleanup: ${err?.message || err}`, 'error');
    }

    setCallState('idle');
    log('=== CALL ENDED ===', 'info');
  }, [callState, log]);

  // Format duration
  const formatDuration = (seconds: number): string => {
    const mins = Math.floor(seconds / 60);
    const secs = seconds % 60;
    return `${mins}:${secs.toString().padStart(2, '0')}`;
  };

  // Get log color
  const getLogColor = (type: LogEntry['type']): string => {
    switch (type) {
      case 'success': return '#4ade80';
      case 'error': return '#f87171';
      case 'event': return '#60a5fa';
      default: return '#e5e5e5';
    }
  };

  return (
    <SafeAreaView style={styles.container} edges={['top']}>
      {/* Header */}
      <View style={styles.header}>
        <Text style={styles.title}>Voice Debug</Text>
        <Text style={styles.subtitle}>{VOICE_NAME}</Text>
      </View>

      {/* Call Status */}
      <View style={styles.statusBar}>
        <View style={styles.statusLeft}>
          <View style={[
            styles.statusDot,
            { backgroundColor: callState === 'connected' ? '#4ade80' : callState === 'connecting' ? '#fbbf24' : '#6b7280' }
          ]} />
          <Text style={styles.statusText}>
            {callState === 'idle' && 'Ready'}
            {callState === 'connecting' && 'Connecting...'}
            {callState === 'connected' && `Connected ${formatDuration(callDuration)}`}
            {callState === 'ending' && 'Ending...'}
          </Text>
        </View>
        <Text style={styles.logCount}>{logs.length} logs</Text>
      </View>

      {/* Control Buttons */}
      <View style={styles.controls}>
        {callState === 'idle' ? (
          <TouchableOpacity style={styles.startButton} onPress={startCall}>
            <Ionicons name="call" size={24} color="#fff" />
            <Text style={styles.buttonText}>Start Call</Text>
          </TouchableOpacity>
        ) : (
          <TouchableOpacity
            style={styles.endButton}
            onPress={endCall}
            disabled={callState === 'ending'}
          >
            <Ionicons name="call" size={24} color="#fff" style={{ transform: [{ rotate: '135deg' }] }} />
            <Text style={styles.buttonText}>End Call</Text>
          </TouchableOpacity>
        )}

        <TouchableOpacity style={styles.copyButton} onPress={copyLogs}>
          <Ionicons name="copy" size={20} color="#fff" />
          <Text style={styles.smallButtonText}>Copy</Text>
        </TouchableOpacity>

        <TouchableOpacity style={styles.shareButton} onPress={shareLogs}>
          <Ionicons name="share" size={20} color="#fff" />
          <Text style={styles.smallButtonText}>Share</Text>
        </TouchableOpacity>

        <TouchableOpacity style={styles.clearButton} onPress={clearLogs}>
          <Ionicons name="trash" size={20} color="#fff" />
          <Text style={styles.smallButtonText}>Clear</Text>
        </TouchableOpacity>
      </View>

      {/* Logs */}
      <FlatList
        ref={flatListRef}
        data={logs}
        keyExtractor={(item) => item.id}
        style={styles.logsList}
        contentContainerStyle={styles.logsContent}
        renderItem={({ item }) => (
          <Text style={[styles.logEntry, { color: getLogColor(item.type) }]}>
            <Text style={styles.logTime}>[{item.time}]</Text> {item.message}
          </Text>
        )}
        ListEmptyComponent={
          <View style={styles.emptyContainer}>
            <Ionicons name="terminal" size={48} color="#6b7280" />
            <Text style={styles.emptyText}>Press "Start Call" to begin</Text>
          </View>
        }
      />
    </SafeAreaView>
  );
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    backgroundColor: '#0f0f0f',
  },
  header: {
    padding: Spacing.md,
    borderBottomWidth: 1,
    borderBottomColor: '#333',
  },
  title: {
    fontSize: 24,
    fontWeight: '700',
    color: '#fff',
  },
  subtitle: {
    fontSize: 14,
    color: '#888',
    marginTop: 2,
  },
  statusBar: {
    flexDirection: 'row',
    justifyContent: 'space-between',
    alignItems: 'center',
    paddingHorizontal: Spacing.md,
    paddingVertical: Spacing.sm,
    backgroundColor: '#1a1a1a',
  },
  statusLeft: {
    flexDirection: 'row',
    alignItems: 'center',
  },
  statusDot: {
    width: 10,
    height: 10,
    borderRadius: 5,
    marginRight: 8,
  },
  statusText: {
    color: '#fff',
    fontSize: 14,
    fontWeight: '500',
  },
  logCount: {
    color: '#888',
    fontSize: 12,
  },
  controls: {
    flexDirection: 'row',
    padding: Spacing.md,
    gap: 10,
    borderBottomWidth: 1,
    borderBottomColor: '#333',
  },
  startButton: {
    flex: 1,
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'center',
    backgroundColor: '#22c55e',
    paddingVertical: 14,
    borderRadius: 12,
    gap: 8,
  },
  endButton: {
    flex: 1,
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'center',
    backgroundColor: '#ef4444',
    paddingVertical: 14,
    borderRadius: 12,
    gap: 8,
  },
  buttonText: {
    color: '#fff',
    fontSize: 16,
    fontWeight: '600',
  },
  copyButton: {
    alignItems: 'center',
    justifyContent: 'center',
    backgroundColor: '#3b82f6',
    paddingVertical: 10,
    paddingHorizontal: 12,
    borderRadius: 10,
  },
  shareButton: {
    alignItems: 'center',
    justifyContent: 'center',
    backgroundColor: '#8b5cf6',
    paddingVertical: 10,
    paddingHorizontal: 12,
    borderRadius: 10,
  },
  clearButton: {
    alignItems: 'center',
    justifyContent: 'center',
    backgroundColor: '#6b7280',
    paddingVertical: 10,
    paddingHorizontal: 12,
    borderRadius: 10,
  },
  smallButtonText: {
    color: '#fff',
    fontSize: 10,
    fontWeight: '500',
    marginTop: 2,
  },
  logsList: {
    flex: 1,
  },
  logsContent: {
    padding: Spacing.sm,
    paddingBottom: 100,
  },
  logEntry: {
    fontSize: 12,
    fontFamily: Platform.OS === 'ios' ? 'Menlo' : 'monospace',
    lineHeight: 18,
    marginBottom: 2,
  },
  logTime: {
    color: '#888',
  },
  emptyContainer: {
    alignItems: 'center',
    justifyContent: 'center',
    paddingTop: 100,
  },
  emptyText: {
    color: '#6b7280',
    fontSize: 16,
    marginTop: 12,
  },
});