import { useTheme } from '@/components/ThemeContext';
import { useInfiniteQuery, useQueryClient } from '@tanstack/react-query';
import { useVideoPlayer, VideoPlayer, VideoView } from 'expo-video';
import { Play } from 'lucide-react-native';
import React, { useEffect, useRef, useState } from 'react';
import { useTranslation } from 'react-i18next';
import {
  ActivityIndicator,
  Animated,
  RefreshControl,
  StyleSheet,
  Text,
  TouchableOpacity,
  View,
} from 'react-native';
import { SafeAreaView } from 'react-native-safe-area-context';
import { announcement_api } from '../lib/api';
import AnnouncementCard from './AnnouncementCard';
import EmptyState from './EmptyState';

function VideoCard({ player }: { player: VideoPlayer }) {
  const [isPlaying, setIsPlaying] = useState(false);

  useEffect(() => {
    const subscription = player.addListener('playingChange', (state) => {
      setIsPlaying(state.isPlaying);
    });

    return () => {
      subscription.remove();
    };
  }, [player]);

  return (
    <View>
      <VideoView player={player} style={styles.video} contentFit="contain" />

      {!isPlaying && (
        <View style={styles.playOverlay}>
          <TouchableOpacity
            style={styles.playButton}
            onPress={() => {
              player.play();
              setIsPlaying(true);
            }}
          >
            <Play color="white" size={26} fill="black" />
          </TouchableOpacity>
        </View>
      )}
    </View>
  );
}

export default function DashboardScreen() {
  const queryClient = useQueryClient();
  const fadeAnim = useRef(new Animated.Value(0)).current;
  const { isDark } = useTheme();
  const { t, i18n } = useTranslation();

  const userLang = i18n.language.startsWith('ru')
    ? 'ru'
    : i18n.language.startsWith('en')
      ? 'en'
      : 'uz';

  const [selectedLang, setSelectedLang] = useState<'uz' | 'ru' | 'en'>(userLang);

  const theme = {
    background: isDark ? '#0f172a' : '#f8fafc',
    primary: '#2563eb',
    text: isDark ? '#f8fafc' : '#0f172a',
    loaderBg: isDark ? '#0f172a' : '#ffffff',
  };

  // Announcements query
  const { data, isLoading, isRefetching, fetchNextPage, hasNextPage } = useInfiniteQuery({
    queryKey: ['announcements_list'],
    queryFn: async ({ pageParam = 1 }) => {
      const res = await announcement_api.list({
        page: pageParam,
        page_size: 10,
      });
      return res.data.data;
    },
    getNextPageParam: (lastPage) =>
      lastPage.current_page < lastPage.total_pages ? lastPage.current_page + 1 : undefined,
    initialPageParam: 1,
  });

  const allAnnouncements = data?.pages.flatMap((p) => p.results) ?? [];

  useEffect(() => {
    fadeAnim.setValue(0);
    Animated.timing(fadeAnim, {
      toValue: 1,
      duration: 300,
      useNativeDriver: true,
    }).start();
  }, [allAnnouncements]);

  // Announcement videos
  const videos = {
    uz: require('@/assets/announcements-video/video_uz.mp4'),
    ru: require('@/assets/announcements-video/video_ru.mp4'),
    en: require('@/assets/announcements-video/video_en.mp4'),
  };

  // Government videos: faqat RU mavjud
  const govermentVideos: Partial<Record<'uz' | 'ru' | 'en', any>> = {
    ru: require('@/assets/goverment/video_ru.mp4'),
  };

  // Update selected language
  useEffect(() => {
    const lang = i18n.language.startsWith('ru')
      ? 'ru'
      : i18n.language.startsWith('en')
        ? 'en'
        : 'uz';
    setSelectedLang(lang);
  }, [i18n.language]);

  // 🔹 Hooks: conditional emas, har doim chaqiriladi
  const player = useVideoPlayer(videos[selectedLang], (player) => {
    player.loop = false;
    player.volume = 1;
    player.muted = false;
  });

  const govermentVideoSource = govermentVideos[selectedLang] ?? null;

  const player2 = useVideoPlayer(govermentVideoSource, (player) => {
    if (!govermentVideoSource) return; // no video, do nothing
    player.loop = false;
    player.volume = 1;
    player.muted = false;
  });

  const onRefresh = () => {
    queryClient.refetchQueries({ queryKey: ['announcements_list'] });
  };

  const loadMore = () => {
    if (hasNextPage) fetchNextPage();
  };

  const videoItems = [
    { id: '1', player },
    govermentVideoSource && { id: '2', player: player2 },
  ].filter(Boolean) as { id: string; player: VideoPlayer }[];

  const renderVideoHeader = () => (
    <View style={{ marginBottom: 8 }}>
      {videoItems.map((item) => (
        <View key={item.id} style={styles.videoContainer}>
          <VideoCard player={item.player} />
        </View>
      ))}
    </View>
  );

  if (isLoading) {
    return (
      <SafeAreaView style={[styles.container, { backgroundColor: theme.background }]}>
        <View style={[styles.loaderBox, { backgroundColor: theme.loaderBg }]}>
          <ActivityIndicator size="large" color={theme.primary} />
        </View>
      </SafeAreaView>
    );
  }

  return (
    <View style={[styles.container, { backgroundColor: theme.background }]}>
      <Text style={{ color: theme.text, fontSize: 20, marginVertical: 16 }}>
        {t("E'lonlar ro'yxati")}
      </Text>

      <Animated.FlatList
        style={{ flex: 1, opacity: fadeAnim }}
        data={allAnnouncements}
        keyExtractor={(item) => item.id.toString()}
        numColumns={2}
        columnWrapperStyle={styles.columnWrapper}
        renderItem={({ item }) => <AnnouncementCard announcement={item} />}
        ListHeaderComponent={renderVideoHeader}
        refreshControl={
          <RefreshControl
            refreshing={isRefetching}
            onRefresh={onRefresh}
            colors={[theme.primary]}
            tintColor={theme.primary}
            progressBackgroundColor={theme.background}
          />
        }
        ListEmptyComponent={<EmptyState onRefresh={onRefresh} isRefreshing={isRefetching} />}
        onEndReached={loadMore}
        onEndReachedThreshold={0.3}
        contentContainerStyle={{ paddingBottom: 80 }}
        showsVerticalScrollIndicator={false}
      />
    </View>
  );
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    paddingHorizontal: 16,
  },
  loaderBox: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
  },
  columnWrapper: {
    justifyContent: 'space-between',
    gap: 12,
  },
  videoContainer: {
    width: '100%',
    height: 250,
    marginBottom: 8,
    borderRadius: 12,
    overflow: 'hidden',
    backgroundColor: '#000',
  },
  video: {
    width: '100%',
    height: '100%',
  },
  playOverlay: {
    position: 'absolute',
    top: 0,
    left: 0,
    right: 0,
    bottom: 0,
    justifyContent: 'center',
    alignItems: 'center',
  },
  playButton: {
    backgroundColor: 'white',
    borderRadius: 50,
    width: 48,
    height: 48,
    justifyContent: 'center',
    alignItems: 'center',
  },
});