/**
 * Chat Screen - Text Chat with Julia AI
 *
 * Clean text chat interface with integrated voice calls.
 */

import React, { useState, useCallback, useRef, useEffect } from 'react';
import {
  View,
  Text,
  StyleSheet,
  FlatList,
  TextInput,
  TouchableOpacity,
  Modal,
  ActivityIndicator,
  Keyboard,
  Platform,
  Alert,
} from 'react-native';
import { KeyboardAvoidingView } from 'react-native-keyboard-controller';
import { Ionicons } from '@expo/vector-icons';
import { SafeAreaView } from 'react-native-safe-area-context';
import { useRouter } from 'expo-router';
import { activateKeepAwakeAsync, deactivateKeepAwake } from 'expo-keep-awake';
import { api } from '@/services/api';
import { useBeneficiary } from '@/contexts/BeneficiaryContext';
import { useVoiceTranscript } from '@/contexts/VoiceTranscriptContext';
import { useVoiceCall } from '@/contexts/VoiceCallContext';
import { AppColors, BorderRadius, FontSizes, Spacing } from '@/constants/theme';
import type { Message, Beneficiary } from '@/types';

// LiveKit imports
import {
  registerGlobals,
  LiveKitRoom,
  useVoiceAssistant,
  useConnectionState,
  useRoomContext,
  BarVisualizer,
  useTrackTranscription,
  useTracks,
} from '@livekit/react-native';
import { ConnectionState, RoomEvent, Track, TranscriptionSegment } from 'livekit-client';
import { getToken, type BeneficiaryData } from '@/services/livekitService';
import { useAuth } from '@/contexts/AuthContext';

// Register LiveKit globals (must be called before using LiveKit)
registerGlobals();

const API_URL = 'https://eluxnetworks.net/function/well-api/api';

// WellNuo API credentials (same as julia-agent)
const WELLNUO_USER = 'anandk';
const WELLNUO_PASSWORD = 'anandk_8';

// ============================================================================
// SINGLE_DEPLOYMENT_MODE
// When true: sends only deployment_id (no beneficiary_names_dict)
// When false: sends both deployment_id AND beneficiary_names_dict
//
// Use true for WellNuo Lite (single beneficiary per user)
// Use false for full WellNuo app (multiple beneficiaries)
// ============================================================================
const SINGLE_DEPLOYMENT_MODE = true;

// Keywords for question normalization (same as julia-agent/julia-ai/src/agent.py)
const STATUS_KEYWORDS = [
  /\bhow\s+is\b/i,
  /\bhow'?s\b/i,
  /\bhow\s+are\b/i,
  /\btell\s+me\s+about\b/i,
  /\bwhat'?s\s+up\s+with\b/i,
  /\bupdate\s+on\b/i,
  /\bstatus\b/i,
  /\bdoing\b/i,
  /\bfeeling\b/i,
  /\bcheck\s+on\b/i,
  /\bis\s+\w+\s+okay\b/i,
  /\bis\s+\w+\s+alright\b/i,
  /\bis\s+\w+\s+fine\b/i,
  /\bokay\?\b/i,
  /\balright\?\b/i,
];

const SUBJECT_KEYWORDS = [
  /\bdad\b/i,
  /\bfather\b/i,
  /\bferdinand\b/i,
  /\bhim\b/i,
  /\bhe\b/i,
  /\bmy\s+dad\b/i,
  /\bmy\s+father\b/i,
  /\bthe\s+patient\b/i,
  /\bloved\s+one\b/i,
  /\bparent\b/i,
  /\bgrandpa\b/i,
  /\bgrandfather\b/i,
];

/**
 * Transform user questions into format WellNuo API understands.
 * WellNuo API only responds with real sensor data for very specific phrases.
 * This function maps common user questions to those phrases.
 * (Same logic as julia-agent/julia-ai/src/agent.py normalize_question)
 */
function normalizeQuestion(userMessage: string): string {
  const msgLower = userMessage.toLowerCase().trim();

  const isStatusQuery = STATUS_KEYWORDS.some(pattern => pattern.test(msgLower));
  const isAboutRecipient = SUBJECT_KEYWORDS.some(pattern => pattern.test(msgLower));

  // If asking about the care recipient's general status
  if (isStatusQuery && isAboutRecipient) {
    console.log(`[Chat] Normalized '${userMessage}' -> 'how is dad doing'`);
    return 'how is dad doing';
  }

  // Generic status questions without clear subject - assume they mean the care recipient
  if (isStatusQuery && !isAboutRecipient) {
    console.log(`[Chat] Normalized '${userMessage}' -> 'how is dad doing' (assumed recipient)`);
    return 'how is dad doing';
  }

  // If no transformation needed, return original
  console.log(`[Chat] No normalization applied to: '${userMessage}'`);
  return userMessage;
}

// ============================================================================
// Voice Call Overlay Component
// ============================================================================

interface VoiceCallOverlayProps {
  onHangUp: () => void;
  onMinimize: () => void;
  onTranscript: (role: 'user' | 'assistant', text: string) => void;
  onDurationUpdate: (seconds: number) => void;
  beneficiaryName?: string;
}

function VoiceCallContent({ onHangUp, onMinimize, onTranscript, onDurationUpdate, beneficiaryName }: VoiceCallOverlayProps) {
  const room = useRoomContext();
  const connectionState = useConnectionState();
  const { state: agentState, audioTrack } = useVoiceAssistant();
  const [callDuration, setCallDuration] = useState(0);
  const [lastProcessedId, setLastProcessedId] = useState<string | null>(null);

  // Track all audio tracks for transcription
  const tracks = useTracks([Track.Source.Microphone], { onlySubscribed: true });

  // Get transcription from agent's audio track
  const { segments: agentSegments } = useTrackTranscription(audioTrack);

  // Get transcription from user's microphone
  const localTrack = tracks.find(t => t.participant?.isLocal);
  const { segments: userSegments } = useTrackTranscription(localTrack);

  // Process agent transcription
  useEffect(() => {
    if (agentSegments && agentSegments.length > 0) {
      const lastSegment = agentSegments[agentSegments.length - 1];
      if (lastSegment && lastSegment.final && lastSegment.id !== lastProcessedId) {
        setLastProcessedId(lastSegment.id);
        onTranscript('assistant', lastSegment.text);
        console.log('[VoiceCall] Agent said:', lastSegment.text);
      }
    }
  }, [agentSegments, lastProcessedId, onTranscript]);

  // Process user transcription
  const [lastUserSegmentId, setLastUserSegmentId] = useState<string | null>(null);
  useEffect(() => {
    if (userSegments && userSegments.length > 0) {
      const lastSegment = userSegments[userSegments.length - 1];
      if (lastSegment && lastSegment.final && lastSegment.id !== lastUserSegmentId) {
        setLastUserSegmentId(lastSegment.id);
        onTranscript('user', lastSegment.text);
        console.log('[VoiceCall] User said:', lastSegment.text);
      }
    }
  }, [userSegments, lastUserSegmentId, onTranscript]);

  // Call duration timer
  useEffect(() => {
    if (connectionState === ConnectionState.Connected) {
      const interval = setInterval(() => {
        setCallDuration(prev => {
          const newDuration = prev + 1;
          onDurationUpdate(newDuration);
          return newDuration;
        });
      }, 1000);
      return () => clearInterval(interval);
    }
  }, [connectionState, onDurationUpdate]);

  // Keep screen awake during call
  useEffect(() => {
    activateKeepAwakeAsync('voice-call');
    return () => {
      deactivateKeepAwake('voice-call');
    };
  }, []);

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

  // Get status text based on agent state
  const getStatusText = () => {
    if (connectionState === ConnectionState.Connecting) return 'Connecting...';
    if (connectionState === ConnectionState.Reconnecting) return 'Reconnecting...';
    if (connectionState !== ConnectionState.Connected) return 'Disconnected';

    switch (agentState) {
      case 'listening': return 'Listening...';
      case 'thinking': return 'Thinking...';
      case 'speaking': return 'Speaking...';
      case 'connecting': return 'Connecting to Julia...';
      case 'initializing': return 'Starting...';
      default: return 'Connected';
    }
  };

  return (
    <View style={voiceStyles.container}>
      <View style={voiceStyles.content}>
        {/* Avatar */}
        <View style={voiceStyles.avatarContainer}>
          <View style={[
            voiceStyles.avatar,
            agentState === 'speaking' && voiceStyles.avatarSpeaking,
          ]}>
            <Text style={voiceStyles.avatarText}>J</Text>
          </View>
          {agentState === 'speaking' && (
            <View style={voiceStyles.speakingRing} />
          )}
        </View>

        {/* Name and status */}
        <Text style={voiceStyles.name}>Julia AI</Text>
        {beneficiaryName && (
          <Text style={voiceStyles.beneficiary}>About {beneficiaryName}</Text>
        )}
        <Text style={voiceStyles.status}>{getStatusText()}</Text>

        {/* Duration */}
        {connectionState === ConnectionState.Connected && (
          <Text style={voiceStyles.duration}>{formatDuration(callDuration)}</Text>
        )}

        {/* Audio Visualizer */}
        {audioTrack && agentState === 'speaking' && (
          <View style={voiceStyles.visualizerContainer}>
            <BarVisualizer
              trackRef={{ participant: audioTrack.participant, source: Track.Source.Microphone, publication: audioTrack.publication }}
              barCount={5}
              options={{ minHeight: 10 }}
            />
          </View>
        )}
      </View>

      {/* Call controls */}
      <View style={voiceStyles.callControls}>
        {/* Minimize button */}
        <TouchableOpacity style={voiceStyles.minimizeButton} onPress={onMinimize}>
          <Ionicons name="chevron-down" size={28} color={AppColors.white} />
        </TouchableOpacity>

        {/* Hang up button */}
        <TouchableOpacity style={voiceStyles.hangUpButton} onPress={onHangUp}>
          <Ionicons name="call" size={32} color={AppColors.white} style={{ transform: [{ rotate: '135deg' }] }} />
        </TouchableOpacity>

        {/* Placeholder for symmetry */}
        <View style={voiceStyles.controlPlaceholder} />
      </View>
    </View>
  );
}

const voiceStyles = StyleSheet.create({
  container: {
    flex: 1,
    backgroundColor: 'rgba(0, 0, 0, 0.95)',
    justifyContent: 'space-between',
    alignItems: 'center',
    paddingVertical: 60,
  },
  content: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
  },
  avatarContainer: {
    position: 'relative',
    marginBottom: Spacing.lg,
  },
  avatar: {
    width: 120,
    height: 120,
    borderRadius: 60,
    backgroundColor: AppColors.success,
    justifyContent: 'center',
    alignItems: 'center',
  },
  avatarSpeaking: {
    backgroundColor: AppColors.primary,
  },
  avatarText: {
    fontSize: 48,
    fontWeight: '600',
    color: AppColors.white,
  },
  speakingRing: {
    position: 'absolute',
    top: -10,
    left: -10,
    right: -10,
    bottom: -10,
    borderRadius: 70,
    borderWidth: 3,
    borderColor: AppColors.primary,
    opacity: 0.5,
  },
  name: {
    fontSize: FontSizes['2xl'],
    fontWeight: '600',
    color: AppColors.white,
    marginBottom: Spacing.xs,
  },
  beneficiary: {
    fontSize: FontSizes.base,
    color: 'rgba(255, 255, 255, 0.7)',
    marginBottom: Spacing.sm,
  },
  status: {
    fontSize: FontSizes.base,
    color: AppColors.success,
    marginBottom: Spacing.md,
  },
  duration: {
    fontSize: FontSizes.lg,
    color: 'rgba(255, 255, 255, 0.8)',
    fontVariant: ['tabular-nums'],
  },
  visualizerContainer: {
    marginTop: Spacing.xl,
    height: 60,
    width: 200,
  },
  callControls: {
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'center',
    gap: Spacing.xl,
    marginBottom: Spacing.xl,
  },
  minimizeButton: {
    width: 56,
    height: 56,
    borderRadius: 28,
    backgroundColor: 'rgba(255, 255, 255, 0.2)',
    justifyContent: 'center',
    alignItems: 'center',
  },
  hangUpButton: {
    width: 72,
    height: 72,
    borderRadius: 36,
    backgroundColor: AppColors.error,
    justifyContent: 'center',
    alignItems: 'center',
  },
  controlPlaceholder: {
    width: 56,
    height: 56,
  },
});

export default function ChatScreen() {
  const router = useRouter();
  const { currentBeneficiary, setCurrentBeneficiary } = useBeneficiary();
  const { addTranscriptEntry, clearTranscript } = useVoiceTranscript();
  const { user } = useAuth();
  const {
    callState,
    startCall,
    endCall: endVoiceCallContext,
    minimizeCall,
    maximizeCall,
    updateDuration,
    isCallActive,
  } = useVoiceCall();

  // Chat state
  const [messages, setMessages] = useState<Message[]>([
    {
      id: '1',
      role: 'assistant',
      content: 'Hello! I\'m Julia, your AI wellness assistant. You can type a message or tap the phone button to start a voice call.',
      timestamp: new Date(),
    },
  ]);
  const [sortNewestFirst, setSortNewestFirst] = useState(false);

  // Voice call state (local connecting state only)
  const [isConnectingVoice, setIsConnectingVoice] = useState(false);

  // Track if we've shown the voice call separator for current call
  const [hasShownVoiceSeparator, setHasShownVoiceSeparator] = useState(false);

  // Reset separator flag when starting a new call
  useEffect(() => {
    if (isCallActive && !hasShownVoiceSeparator) {
      // Will show separator on first voice message
    } else if (!isCallActive) {
      setHasShownVoiceSeparator(false);
    }
  }, [isCallActive]);
  const [input, setInput] = useState('');
  const [isSending, setIsSending] = useState(false);
  const flatListRef = useRef<FlatList>(null);

  // Beneficiary picker
  const [showBeneficiaryPicker, setShowBeneficiaryPicker] = useState(false);
  const [beneficiaries, setBeneficiaries] = useState<Beneficiary[]>([]);
  const [loadingBeneficiaries, setLoadingBeneficiaries] = useState(false);

  // Custom deployment ID from settings
  const [customDeploymentId, setCustomDeploymentId] = useState<string | null>(null);

  // Load custom deployment ID from settings
  useEffect(() => {
    const loadCustomDeploymentId = async () => {
      const saved = await api.getDeploymentId();
      setCustomDeploymentId(saved);
    };
    loadCustomDeploymentId();
  }, []);

  // Load beneficiaries
  const loadBeneficiaries = useCallback(async () => {
    setLoadingBeneficiaries(true);
    try {
      const response = await api.getAllBeneficiaries();
      if (response.ok && response.data) {
        setBeneficiaries(response.data);
        return response.data;
      }
      return [];
    } catch (error) {
      console.error('Failed to load beneficiaries:', error);
      return [];
    } finally {
      setLoadingBeneficiaries(false);
    }
  }, []);

  // Auto-select first beneficiary
  useEffect(() => {
    const autoSelect = async () => {
      if (!currentBeneficiary) {
        const loaded = await loadBeneficiaries();
        if (loaded.length > 0) {
          setCurrentBeneficiary(loaded[0]);
        }
      }
    };
    autoSelect();
  }, []);

  // Helper function to scroll to the latest message based on sort mode
  const scrollToLatestMessage = useCallback((animated = true) => {
    if (sortNewestFirst) {
      // When newest first, latest messages are at top (index 0)
      flatListRef.current?.scrollToOffset({ offset: 0, animated });
    } else {
      // When oldest first, latest messages are at bottom
      flatListRef.current?.scrollToEnd({ animated });
    }
  }, [sortNewestFirst]);

  // Scroll to latest when keyboard shows
  useEffect(() => {
    const keyboardShowListener = Keyboard.addListener(
      Platform.OS === 'ios' ? 'keyboardWillShow' : 'keyboardDidShow',
      () => {
        setTimeout(() => {
          scrollToLatestMessage(true);
        }, 100);
      }
    );
    return () => keyboardShowListener.remove();
  }, [scrollToLatestMessage]);

  const openBeneficiaryPicker = useCallback(() => {
    setShowBeneficiaryPicker(true);
    loadBeneficiaries();
  }, [loadBeneficiaries]);

  const selectBeneficiary = useCallback((beneficiary: Beneficiary) => {
    setCurrentBeneficiary(beneficiary);
    setShowBeneficiaryPicker(false);
  }, [setCurrentBeneficiary]);

  // ============================================================================
  // Voice Call Functions
  // ============================================================================

  // Start voice call
  const startVoiceCall = useCallback(async () => {
    if (isConnectingVoice || isCallActive) return;

    setIsConnectingVoice(true);
    console.log('[Chat] Starting voice call...');

    try {
      // Build beneficiary data for the agent
      // Priority: customDeploymentId from settings > currentBeneficiary > first beneficiary > fallback
      const beneficiaryData: BeneficiaryData = {
        deploymentId: customDeploymentId || currentBeneficiary?.id?.toString() || beneficiaries[0]?.id?.toString() || '21',
        beneficiaryNamesDict: {},
      };

      // Add names dict if not in single deployment mode
      if (!SINGLE_DEPLOYMENT_MODE) {
        beneficiaries.forEach(b => {
          beneficiaryData.beneficiaryNamesDict[b.id.toString()] = b.name;
        });
      }

      // Get LiveKit token
      const userIdStr = user?.user_id?.toString() || 'user-' + Date.now();
      const tokenResponse = await getToken(userIdStr, beneficiaryData);

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

      console.log('[Chat] Got voice token, connecting to room:', tokenResponse.data.roomName);

      // Clear previous transcript and start call via context
      clearTranscript();
      startCall({
        token: tokenResponse.data.token,
        wsUrl: tokenResponse.data.wsUrl,
        beneficiaryName: currentBeneficiary?.name,
        beneficiaryId: currentBeneficiary?.id?.toString(),
      });
    } catch (error) {
      console.error('[Chat] Voice call error:', error);
      Alert.alert(
        'Voice Call Error',
        error instanceof Error ? error.message : 'Failed to start voice call'
      );
    } finally {
      setIsConnectingVoice(false);
    }
  }, [isConnectingVoice, isCallActive, currentBeneficiary, beneficiaries, user, clearTranscript, startCall, customDeploymentId]);

  // End voice call
  const endVoiceCall = useCallback(() => {
    console.log('[Chat] Ending voice call...');
    endVoiceCallContext();
  }, [endVoiceCallContext]);

  // Handle voice transcript entries - add to chat in real-time
  const handleVoiceTranscript = useCallback((role: 'user' | 'assistant', text: string) => {
    if (!text.trim()) return;

    // Add separator before first voice message of this call
    if (!hasShownVoiceSeparator) {
      const separatorMessage: Message = {
        id: `voice-separator-${Date.now()}`,
        role: 'assistant',
        content: 'Voice Call',
        timestamp: new Date(),
        isSystem: true,
      };
      setMessages(prev => [...prev, separatorMessage]);
      setHasShownVoiceSeparator(true);
    }

    // Create voice message and add to chat immediately
    const voiceMessage: Message = {
      id: `voice-${Date.now()}-${Math.random().toString(36).slice(2)}`,
      role,
      content: text.trim(),
      timestamp: new Date(),
      isVoice: true,
    };

    setMessages(prev => [...prev, voiceMessage]);

    // Scroll to latest message (respects sort mode)
    setTimeout(() => {
      scrollToLatestMessage(true);
    }, 100);

    // Also store in transcript context for persistence
    addTranscriptEntry(role, text);
  }, [hasShownVoiceSeparator, addTranscriptEntry, scrollToLatestMessage]);

  // Cached API token for WellNuo
  const apiTokenRef = useRef<string | null>(null);

  // Get WellNuo API token (same credentials as julia-agent)
  const getWellNuoToken = useCallback(async (): Promise<string> => {
    if (apiTokenRef.current) {
      return apiTokenRef.current;
    }

    const nonce = Math.floor(Math.random() * 1000000).toString();
    const response = await fetch(API_URL, {
      method: 'POST',
      headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
      body: new URLSearchParams({
        function: 'credentials',
        clientId: 'MA_001',
        user_name: WELLNUO_USER,
        ps: WELLNUO_PASSWORD,
        nonce: nonce,
      }).toString(),
    });

    const data = await response.json();
    if (data.status === '200 OK' && data.access_token) {
      apiTokenRef.current = data.access_token;
      console.log('[Chat] WellNuo token obtained');
      return data.access_token;
    }
    throw new Error('Failed to authenticate with WellNuo API');
  }, []);

  // Text chat - send message via API (same as julia-agent)
  const sendTextMessage = useCallback(async () => {
    const trimmedInput = input.trim();
    if (!trimmedInput || isSending) return;

    const userMessage: Message = {
      id: Date.now().toString(),
      role: 'user',
      content: trimmedInput,
      timestamp: new Date(),
    };

    setMessages(prev => [...prev, userMessage]);
    setInput('');
    setIsSending(true);
    Keyboard.dismiss();

    try {
      // Get WellNuo API token (uses anandk credentials like julia-agent)
      const token = await getWellNuoToken();

      // Normalize question to format WellNuo API understands
      // (same logic as julia-agent/julia-ai/src/agent.py)
      const normalizedQuestion = normalizeQuestion(trimmedInput);

      // Build beneficiary_names_dict from all loaded beneficiaries
      // Format: {"21": "papa", "69": "David"}
      const beneficiaryNamesDict: Record<string, string> = {};
      beneficiaries.forEach(b => {
        beneficiaryNamesDict[b.id.toString()] = b.name;
      });

      // Get deployment_id: custom from settings > current beneficiary > first beneficiary > fallback
      const deploymentId = customDeploymentId || currentBeneficiary?.id?.toString() || beneficiaries[0]?.id?.toString() || '21';

      // Call API with EXACT same params as voice agent
      // SINGLE_DEPLOYMENT_MODE: sends only deployment_id (no beneficiary_names_dict)
      const requestParams: Record<string, string> = {
        function: 'ask_wellnuo_ai',
        clientId: 'MA_001',
        user_name: WELLNUO_USER,
        token: token,
        question: normalizedQuestion,
        deployment_id: deploymentId,
      };

      // Only add beneficiary_names_dict if NOT in single deployment mode
      if (!SINGLE_DEPLOYMENT_MODE) {
        requestParams.beneficiary_names_dict = JSON.stringify(beneficiaryNamesDict);
      }

      const response = await fetch(API_URL, {
        method: 'POST',
        headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
        body: new URLSearchParams(requestParams).toString(),
      });

      const data = await response.json();

      if (data.ok && data.response?.body) {
        const assistantMessage: Message = {
          id: (Date.now() + 1).toString(),
          role: 'assistant',
          content: data.response.body,
          timestamp: new Date(),
        };
        setMessages(prev => [...prev, assistantMessage]);
      } else {
        // Token might be expired, clear and retry once
        if (data.status === '401 Unauthorized') {
          apiTokenRef.current = null;
          throw new Error('Session expired, please try again');
        }
        throw new Error('Could not get response');
      }
    } catch (error) {
      const errorMessage: Message = {
        id: (Date.now() + 1).toString(),
        role: 'assistant',
        content: `Sorry, I encountered an error: ${error instanceof Error ? error.message : 'Unknown error'}`,
        timestamp: new Date(),
      };
      setMessages(prev => [...prev, errorMessage]);
    } finally {
      setIsSending(false);
    }
  }, [input, isSending, getWellNuoToken, customDeploymentId, currentBeneficiary, beneficiaries]);

  // Render message bubble
  const renderMessage = ({ item }: { item: Message }) => {
    const isUser = item.role === 'user';
    const isVoice = item.isVoice;
    const isSystem = item.isSystem;

    // System messages (like "Voice Call Transcript" separator)
    if (isSystem) {
      return (
        <View style={styles.systemMessageContainer}>
          <View style={styles.systemMessageLine} />
          <View style={styles.systemMessageBadge}>
            <Ionicons name="call" size={12} color={AppColors.textMuted} />
            <Text style={styles.systemMessageText}>{item.content.replace(/---/g, '').trim()}</Text>
          </View>
          <View style={styles.systemMessageLine} />
        </View>
      );
    }

    return (
      <View style={[styles.messageContainer, isUser ? styles.userMessageContainer : styles.assistantMessageContainer]}>
        {!isUser && (
          <View style={styles.avatarContainer}>
            <Text style={styles.avatarText}>J</Text>
          </View>
        )}
        <View style={[styles.messageBubble, isUser ? styles.userBubble : styles.assistantBubble, isVoice && styles.voiceBubble]}>
          {isVoice && (
            <View style={styles.voiceIndicator}>
              <Text style={styles.voiceIndicatorEmoji}>🎤</Text>
            </View>
          )}
          <Text style={[styles.messageText, isUser ? styles.userMessageText : styles.assistantMessageText]}>
            {item.content}
          </Text>
          <Text style={[styles.timestamp, isUser && styles.userTimestamp]}>
            {item.timestamp.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' })}
          </Text>
        </View>
      </View>
    );
  };

  return (
    <SafeAreaView style={styles.container} edges={['top', 'bottom']}>
      {/* Header */}
      <View style={styles.header}>
        <TouchableOpacity style={styles.backButton} onPress={() => router.push('/(tabs)')}>
          <Ionicons name="arrow-back" size={24} color={AppColors.textPrimary} />
        </TouchableOpacity>
        <View style={styles.headerInfo}>
          <View style={styles.headerAvatar}>
            <Text style={styles.headerAvatarText}>J</Text>
          </View>
          <View>
            <Text style={styles.headerTitle}>Julia AI</Text>
            <Text style={styles.headerSubtitle}>
              {currentBeneficiary ? `About ${currentBeneficiary.name}` : 'Online'}
            </Text>
          </View>
        </View>
        <TouchableOpacity
          style={styles.headerButton}
          onPress={() => setSortNewestFirst(prev => !prev)}
        >
          <Ionicons
            name={sortNewestFirst ? 'arrow-up' : 'arrow-down'}
            size={22}
            color={AppColors.textSecondary}
          />
        </TouchableOpacity>
        <TouchableOpacity
          style={styles.headerButton}
          onPress={() => {
            Alert.alert(
              'Clear Chat',
              'Are you sure you want to clear all messages?',
              [
                { text: 'Cancel', style: 'cancel' },
                {
                  text: 'Clear',
                  style: 'destructive',
                  onPress: () => {
                    setMessages([
                      {
                        id: '1',
                        role: 'assistant',
                        content: 'Hello! I\'m Julia, your AI wellness assistant. You can type a message or tap the phone button to start a voice call.',
                        timestamp: new Date(),
                      },
                    ]);
                  },
                },
              ]
            );
          }}
        >
          <Ionicons name="trash-outline" size={22} color={AppColors.textSecondary} />
        </TouchableOpacity>
      </View>

      {/* Beneficiary Picker Modal */}
      <Modal
        visible={showBeneficiaryPicker}
        transparent
        animationType="slide"
        onRequestClose={() => setShowBeneficiaryPicker(false)}
      >
        <View style={styles.modalOverlay}>
          <View style={styles.modalContent}>
            <View style={styles.modalHeader}>
              <Text style={styles.modalTitle}>Select Beneficiary</Text>
              <TouchableOpacity onPress={() => setShowBeneficiaryPicker(false)}>
                <Ionicons name="close" size={24} color={AppColors.textPrimary} />
              </TouchableOpacity>
            </View>

            {loadingBeneficiaries ? (
              <View style={styles.modalLoading}>
                <ActivityIndicator size="large" color={AppColors.primary} />
              </View>
            ) : beneficiaries.length === 0 ? (
              <View style={styles.modalEmpty}>
                <Text style={styles.emptyText}>No beneficiaries found</Text>
              </View>
            ) : (
              <FlatList
                data={beneficiaries}
                keyExtractor={(item) => item.id.toString()}
                renderItem={({ item }) => (
                  <TouchableOpacity
                    style={[
                      styles.beneficiaryItem,
                      currentBeneficiary?.id === item.id && styles.beneficiaryItemSelected,
                    ]}
                    onPress={() => selectBeneficiary(item)}
                  >
                    <View style={styles.beneficiaryAvatar}>
                      <Text style={styles.beneficiaryAvatarText}>
                        {item.name.split(' ').map(n => n[0]).join('').slice(0, 2)}
                      </Text>
                    </View>
                    <View style={styles.beneficiaryInfo}>
                      <Text style={styles.beneficiaryName}>{item.name}</Text>
                    </View>
                    {currentBeneficiary?.id === item.id && (
                      <Ionicons name="checkmark-circle" size={24} color={AppColors.success} />
                    )}
                  </TouchableOpacity>
                )}
                style={styles.beneficiaryList}
              />
            )}
          </View>
        </View>
      </Modal>

      {/* Messages */}
      <KeyboardAvoidingView
        style={styles.chatContainer}
        behavior="padding"
      >
        <FlatList
          ref={flatListRef}
          data={sortNewestFirst ? [...messages].reverse() : messages}
          keyExtractor={(item) => item.id}
          renderItem={renderMessage}
          contentContainerStyle={styles.messagesList}
          showsVerticalScrollIndicator={false}
          onContentSizeChange={() => {
            scrollToLatestMessage(true);
          }}
        />

        {/* Input */}
        <View style={styles.inputContainer}>
          {/* Voice Call Button */}
          <TouchableOpacity
            style={[
              styles.voiceButton,
              (isConnectingVoice || isCallActive) && styles.voiceButtonConnecting,
            ]}
            onPress={isCallActive ? maximizeCall : startVoiceCall}
            disabled={isConnectingVoice}
          >
            {isConnectingVoice ? (
              <ActivityIndicator size="small" color={AppColors.primary} />
            ) : isCallActive ? (
              <Ionicons name="call" size={20} color={AppColors.success} />
            ) : (
              <Ionicons name="call" size={20} color={AppColors.primary} />
            )}
          </TouchableOpacity>

          <TextInput
            style={styles.input}
            placeholder="Type a message..."
            placeholderTextColor={AppColors.textMuted}
            value={input}
            onChangeText={setInput}
            multiline
            maxLength={1000}
            onSubmitEditing={sendTextMessage}
          />
          <TouchableOpacity
            style={[styles.sendButton, (!input.trim() || isSending) && styles.sendButtonDisabled]}
            onPress={sendTextMessage}
            disabled={!input.trim() || isSending}
          >
            <Ionicons
              name={isSending ? 'hourglass' : 'send'}
              size={20}
              color={input.trim() && !isSending ? AppColors.white : AppColors.textMuted}
            />
          </TouchableOpacity>
        </View>
      </KeyboardAvoidingView>

      {/* Voice Call Modal */}
      <Modal
        visible={isCallActive && !callState.isMinimized}
        animationType="slide"
        presentationStyle="fullScreen"
        onRequestClose={minimizeCall}
      >
        <SafeAreaView style={{ flex: 1, backgroundColor: 'black' }} edges={['top', 'bottom']}>
          {callState.token && callState.wsUrl ? (
            <LiveKitRoom
              serverUrl={callState.wsUrl}
              token={callState.token}
              connect={true}
              audio={true}
              video={false}
              onConnected={() => console.log('[Chat] LiveKit connected')}
              onDisconnected={endVoiceCall}
              onError={(error) => {
                console.error('[Chat] LiveKit error:', error);
                Alert.alert('Voice Call Error', error.message);
                endVoiceCall();
              }}
            >
              <VoiceCallContent
                onHangUp={endVoiceCall}
                onMinimize={minimizeCall}
                onTranscript={handleVoiceTranscript}
                onDurationUpdate={updateDuration}
                beneficiaryName={currentBeneficiary?.name}
              />
            </LiveKitRoom>
          ) : (
            <View style={{ flex: 1, justifyContent: 'center', alignItems: 'center' }}>
              <ActivityIndicator size="large" color={AppColors.primary} />
              <Text style={{ color: 'white', marginTop: 16 }}>Connecting...</Text>
            </View>
          )}
        </SafeAreaView>
      </Modal>
    </SafeAreaView>
  );
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    backgroundColor: AppColors.surface,
  },
  header: {
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'space-between',
    paddingHorizontal: Spacing.md,
    paddingVertical: Spacing.sm,
    backgroundColor: AppColors.background,
    borderBottomWidth: 1,
    borderBottomColor: AppColors.border,
  },
  backButton: {
    padding: Spacing.xs,
    marginRight: Spacing.sm,
  },
  headerInfo: {
    flex: 1,
    flexDirection: 'row',
    alignItems: 'center',
  },
  headerAvatar: {
    width: 40,
    height: 40,
    borderRadius: BorderRadius.full,
    backgroundColor: AppColors.success,
    justifyContent: 'center',
    alignItems: 'center',
    marginRight: Spacing.sm,
  },
  headerAvatarText: {
    fontSize: FontSizes.lg,
    fontWeight: '600',
    color: AppColors.white,
  },
  headerTitle: {
    fontSize: FontSizes.lg,
    fontWeight: '600',
    color: AppColors.textPrimary,
  },
  headerSubtitle: {
    fontSize: FontSizes.sm,
    color: AppColors.success,
  },
  headerButton: {
    padding: Spacing.xs,
    marginLeft: Spacing.sm,
  },
  chatContainer: {
    flex: 1,
  },
  messagesList: {
    padding: Spacing.md,
    paddingBottom: Spacing.lg,
  },
  messageContainer: {
    flexDirection: 'row',
    marginBottom: Spacing.md,
    alignItems: 'flex-end',
  },
  userMessageContainer: {
    justifyContent: 'flex-end',
  },
  assistantMessageContainer: {
    justifyContent: 'flex-start',
  },
  avatarContainer: {
    width: 32,
    height: 32,
    borderRadius: BorderRadius.full,
    backgroundColor: AppColors.success,
    justifyContent: 'center',
    alignItems: 'center',
    marginRight: Spacing.xs,
  },
  avatarText: {
    fontSize: FontSizes.sm,
    fontWeight: '600',
    color: AppColors.white,
  },
  messageBubble: {
    maxWidth: '75%',
    padding: Spacing.sm + 4,
    borderRadius: BorderRadius.lg,
  },
  userBubble: {
    backgroundColor: AppColors.primary,
    borderBottomRightRadius: BorderRadius.sm,
  },
  assistantBubble: {
    backgroundColor: AppColors.background,
    borderBottomLeftRadius: BorderRadius.sm,
  },
  messageText: {
    fontSize: FontSizes.base,
    lineHeight: 22,
  },
  userMessageText: {
    color: AppColors.white,
  },
  assistantMessageText: {
    color: AppColors.textPrimary,
  },
  timestamp: {
    fontSize: FontSizes.xs,
    color: AppColors.textMuted,
    marginTop: Spacing.xs,
    alignSelf: 'flex-end',
  },
  userTimestamp: {
    color: 'rgba(255,255,255,0.7)',
  },
  inputContainer: {
    flexDirection: 'row',
    alignItems: 'flex-end',
    padding: Spacing.md,
    backgroundColor: AppColors.background,
    borderTopWidth: 1,
    borderTopColor: AppColors.border,
  },
  input: {
    flex: 1,
    backgroundColor: AppColors.surface,
    borderRadius: BorderRadius.xl,
    paddingHorizontal: Spacing.md,
    paddingVertical: Spacing.sm,
    fontSize: FontSizes.base,
    color: AppColors.textPrimary,
    maxHeight: 100,
    marginRight: Spacing.sm,
  },
  voiceButton: {
    width: 44,
    height: 44,
    borderRadius: BorderRadius.full,
    backgroundColor: AppColors.surface,
    justifyContent: 'center',
    alignItems: 'center',
    marginRight: Spacing.sm,
    borderWidth: 1,
    borderColor: AppColors.primary,
  },
  voiceButtonConnecting: {
    borderColor: AppColors.success,
    backgroundColor: 'rgba(90, 200, 168, 0.1)',
  },
  sendButton: {
    width: 44,
    height: 44,
    borderRadius: BorderRadius.full,
    backgroundColor: AppColors.primary,
    justifyContent: 'center',
    alignItems: 'center',
  },
  sendButtonDisabled: {
    backgroundColor: AppColors.surface,
  },
  // Modal styles
  modalOverlay: {
    flex: 1,
    backgroundColor: 'rgba(0, 0, 0, 0.5)',
    justifyContent: 'flex-end',
  },
  modalContent: {
    backgroundColor: AppColors.background,
    borderTopLeftRadius: BorderRadius.xl,
    borderTopRightRadius: BorderRadius.xl,
    maxHeight: '70%',
    paddingBottom: Spacing.xl,
  },
  modalHeader: {
    flexDirection: 'row',
    justifyContent: 'space-between',
    alignItems: 'center',
    padding: Spacing.md,
    borderBottomWidth: 1,
    borderBottomColor: AppColors.border,
  },
  modalTitle: {
    fontSize: FontSizes.lg,
    fontWeight: '600',
    color: AppColors.textPrimary,
  },
  modalLoading: {
    padding: Spacing.xl,
    alignItems: 'center',
  },
  modalEmpty: {
    padding: Spacing.xl,
    alignItems: 'center',
  },
  emptyText: {
    fontSize: FontSizes.base,
    color: AppColors.textSecondary,
  },
  beneficiaryList: {
    paddingHorizontal: Spacing.md,
  },
  beneficiaryItem: {
    flexDirection: 'row',
    alignItems: 'center',
    padding: Spacing.md,
    backgroundColor: AppColors.surface,
    borderRadius: BorderRadius.md,
    marginTop: Spacing.sm,
  },
  beneficiaryItemSelected: {
    backgroundColor: AppColors.primaryLight || '#E3F2FD',
    borderWidth: 1,
    borderColor: AppColors.primary,
  },
  beneficiaryAvatar: {
    width: 44,
    height: 44,
    borderRadius: BorderRadius.full,
    backgroundColor: AppColors.primary,
    justifyContent: 'center',
    alignItems: 'center',
    marginRight: Spacing.md,
  },
  beneficiaryAvatarText: {
    fontSize: FontSizes.base,
    fontWeight: '600',
    color: AppColors.white,
  },
  beneficiaryInfo: {
    flex: 1,
  },
  beneficiaryName: {
    fontSize: FontSizes.base,
    fontWeight: '500',
    color: AppColors.textPrimary,
  },
  // Voice message styles
  voiceBubble: {
    borderWidth: 1,
    borderColor: 'rgba(59, 130, 246, 0.3)',
  },
  voiceIndicator: {
    position: 'absolute',
    top: 6,
    right: 6,
  },
  voiceIndicatorEmoji: {
    fontSize: 10,
  },
  // System message styles
  systemMessageContainer: {
    flexDirection: 'row',
    alignItems: 'center',
    marginVertical: Spacing.md,
    paddingHorizontal: Spacing.md,
  },
  systemMessageLine: {
    flex: 1,
    height: 1,
    backgroundColor: AppColors.border,
  },
  systemMessageBadge: {
    flexDirection: 'row',
    alignItems: 'center',
    paddingHorizontal: Spacing.sm,
    paddingVertical: 4,
    backgroundColor: AppColors.surface,
    borderRadius: BorderRadius.sm,
    marginHorizontal: Spacing.sm,
  },
  systemMessageText: {
    fontSize: FontSizes.xs,
    color: AppColors.textMuted,
    marginLeft: 4,
  },
});