import { useTheme } from '@/components/ThemeContext';
import { useInfiniteQuery } from '@tanstack/react-query';
import * as Clipboard from 'expo-clipboard';
import { useRouter } from 'expo-router';
import { ArrowLeft, CopyIcon, Gift, HandCoins, Plus, Users } from 'lucide-react-native';
import React, { useState } from 'react';
import { useTranslation } from 'react-i18next';
import {
  ActivityIndicator,
  FlatList,
  Platform,
  Pressable,
  RefreshControl,
  Share,
  StyleSheet,
  Text,
  TouchableOpacity,
  View
} from 'react-native';
import { SafeAreaView } from 'react-native-safe-area-context';
import { Toast } from 'toastify-react-native';
import { user_api } from '../lib/api';

const PAGE_SIZE = 10;

export function ReferralsTab() {
  const router = useRouter();
  const { isDark } = useTheme();
  const { t } = useTranslation();
  const [refreshing, setRefreshing] = useState(false);

  const theme = {
    background: isDark ? '#0f172a' : '#f8fafc',
    cardBg: isDark ? '#1e293b' : '#ffffff',
    text: isDark ? '#ffffff' : '#0f172a',
    subText: isDark ? '#94a3b8' : '#64748b',
    primary: '#3b82f6',
    success: '#10b981',
  };

  const { data, isLoading, isError, fetchNextPage, hasNextPage, refetch } = useInfiniteQuery({
    queryKey: ['my_referrals'],
    queryFn: async ({ pageParam = 1 }) => {
      const res = await user_api.my_referrals({
        page: pageParam,
        page_size: PAGE_SIZE,
      });

      const d = res.data.data;
      return {
        results: d.results ?? [],
        current_page: d.current_page,
        total_pages: d.total_pages,
      };
    },
    getNextPageParam: (lastPage) =>
      lastPage.current_page < lastPage.total_pages ? lastPage.current_page + 1 : undefined,
    initialPageParam: 1,
  });

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

  const onRefresh = async () => {
    setRefreshing(true);
    await refetch();
    setRefreshing(false);
  };

  // Clipboard + Share funksiyasi
  const handleCopyAndShare = async (code: string) => {
    const referralLink = `${code}`;

    // Clipboard-ga nusxa olish
    await Clipboard.setStringAsync(referralLink);

    // Share qilish
    try {
      await Share.share({
        message: referralLink,
        title: t('Referal linkni ulashish'),
      });
    } catch (err) {
      console.log('Share error:', err);
    }

    if (Platform.OS === 'android') {
      Toast.success(t('Refferal kopiya qilindi'));
    }
  };

  if (isLoading) {
    return (
      <SafeAreaView style={{ flex: 1, justifyContent: 'center', alignItems: 'center' }}>
        <ActivityIndicator size="large" />
      </SafeAreaView>
    );
  }

  if (isError) {
    return (
      <View style={[styles.center, { backgroundColor: theme.background }]}>
        <Text style={{ color: 'red' }}>{t('Xatolik yuz berdi')}</Text>
      </View>
    );
  }

  return (
    <View style={[styles.container, { backgroundColor: theme.background }]}>
      {/* Header */}
      <View style={styles.topHeader}>
        <Pressable onPress={() => router.push('/profile')}>
          <ArrowLeft color={theme.text} />
        </Pressable>
        <Text style={[styles.headerTitle, { color: theme.text }]}>{t('Refferallarim')}</Text>
        <Pressable onPress={() => router.push('/profile/added-referalls')}>
          <Plus color={theme.primary} />
        </Pressable>
      </View>

      <FlatList
        data={referrals}
        keyExtractor={(item) => item.id.toString()}
        contentContainerStyle={styles.list}
        refreshControl={
          <RefreshControl refreshing={refreshing} onRefresh={onRefresh} tintColor={theme.primary} />
        }
        onEndReached={() => hasNextPage && fetchNextPage()}
        renderItem={({ item }) => (
          <View style={[styles.card, { backgroundColor: theme.cardBg }]}>
            <View style={styles.cardRow}>
              <View style={styles.cardHeader}>
                <HandCoins size={20} color={theme.primary} />
                <Text style={[styles.code, { color: theme.text }]}>{item.code}</Text>
              </View>
              <TouchableOpacity onPress={() => handleCopyAndShare(item.code)}>
                <CopyIcon size={20} color={theme.primary} />
              </TouchableOpacity>
            </View>

            <Text style={{ color: theme.subText }}>{item.description}</Text>

            <View style={styles.footer}>
              <View style={styles.row}>
                <Users size={16} color={theme.subText} />
                <Text style={[styles.meta, { color: theme.subText }]}>
                  {item.referral_registered_count} {t('foydalanuvchi')}
                </Text>
              </View>

              <Text style={[styles.amount, { color: theme.success }]}>
                {item.referral_income_amount} {t("so'm")}
              </Text>
            </View>
          </View>
        )}
        ListEmptyComponent={() => (
          <View style={styles.emptyContainer}>
            <View
              style={[
                styles.emptyIconWrapper,
                { backgroundColor: theme.cardBg }
              ]}
            >
              <Gift size={40} color={theme.primary} />
            </View>

            <Text style={[styles.emptyTitle, { color: theme.text }]}>
              {t("Refferallar mavjud emas")}
            </Text>
          </View>
        )}
      />
    </View>
  );
}

const styles = StyleSheet.create({
  container: { flex: 1 },
  center: { flex: 1, justifyContent: 'center', alignItems: 'center' },

  topHeader: {
    flexDirection: 'row',
    justifyContent: 'space-between',
    padding: 16,
    alignItems: 'center',
  },
  headerTitle: { fontSize: 18, fontWeight: '700' },

  list: { padding: 16, gap: 12, paddingBottom: 30, flexGrow: 1 },

  card: {
    borderRadius: 16,
    padding: 16,
    gap: 10,
  },

  cardRow: {
    flexDirection: 'row',
    justifyContent: 'space-between',
    alignContent: 'center',
    alignItems: 'center',
  },

  cardHeader: {
    flexDirection: 'row',
    gap: 8,
    alignItems: 'center',
  },

  code: {
    fontSize: 16,
    fontWeight: '700',
  },

  footer: {
    flexDirection: 'row',
    justifyContent: 'space-between',
    marginTop: 6,
  },

  row: {
    flexDirection: 'row',
    gap: 6,
    alignItems: 'center',
  },

  meta: {},
  amount: {
    fontWeight: '700',
  },
  emptyContainer: {
    flex: 1,
    alignItems: 'center',
    justifyContent: 'center',
    paddingHorizontal: 30,
  },

  emptyIconWrapper: {
    width: 80,
    height: 80,
    borderRadius: 40,
    alignItems: 'center',
    justifyContent: 'center',
    marginBottom: 20,
    elevation: 4,
  },

  emptyTitle: {
    fontSize: 18,
    fontWeight: '700',
    marginBottom: 8,
    textAlign: 'center',
  },

  emptyDesc: {
    fontSize: 14,
    textAlign: 'center',
    marginBottom: 20,
    lineHeight: 20,
  },

  emptyButton: {
    paddingHorizontal: 24,
    paddingVertical: 12,
    borderRadius: 12,
  },

  emptyButtonText: {
    color: '#fff',
    fontWeight: '600',
    fontSize: 15,
  },
});