import React, { useEffect, useState, useRef } from 'react';
import { 
  View, 
  Text, 
  ScrollView, 
  Image, 
  TouchableOpacity,
  ActivityIndicator,
  RefreshControl,
  StyleSheet,
  Animated,
} from 'react-native';
import { SafeAreaView } from 'react-native-safe-area-context';
import { useNavigation } from '@react-navigation/native';
import type { NativeStackNavigationProp } from '@react-navigation/native-stack';
import { ChevronRight, Clock, Tag } from 'lucide-react-native';

import { getAlbums, Album } from '../api/albums';
import { getMembers, Member } from '../api/members';
import { getUpcomingSchedules, Schedule } from '../api/schedules';
import { colors } from '../constants/colors';
import Header from '../components/common/Header';
import type { AlbumStackParamList } from '../navigation/AppNavigator';

type NavigationProp = NativeStackNavigationProp<AlbumStackParamList>;

// 전체 배경색 (tailwind bg-gray-50)
const BG_GRAY = '#F9FAFB';

export default function HomeScreen() {
  const navigation = useNavigation<NavigationProp>();
  const [members, setMembers] = useState<Member[]>([]);
  const [albums, setAlbums] = useState<Album[]>([]);
  const [schedules, setSchedules] = useState<Schedule[]>([]);
  const [loading, setLoading] = useState(true);
  const [refreshing, setRefreshing] = useState(false);
  
  // 애니메이션
  const fadeAnim = useRef(new Animated.Value(0)).current;
  const slideAnim = useRef(new Animated.Value(20)).current;

  const fetchData = async () => {
    try {
      const [membersData, albumsData, schedulesData] = await Promise.all([
        getMembers(),
        getAlbums(),
        getUpcomingSchedules(3),
      ]);
      setMembers(membersData.filter(m => !m.is_former));
      setAlbums(albumsData.slice(0, 2));
      setSchedules(schedulesData || []);
      
      // 애니메이션 시작
      Animated.parallel([
        Animated.timing(fadeAnim, {
          toValue: 1,
          duration: 500,
          useNativeDriver: true,
        }),
        Animated.timing(slideAnim, {
          toValue: 0,
          duration: 500,
          useNativeDriver: true,
        }),
      ]).start();
    } catch (error) {
      console.error('데이터 로드 오류:', error);
    } finally {
      setLoading(false);
      setRefreshing(false);
    }
  };

  useEffect(() => {
    fetchData();
  }, []);

  const onRefresh = () => {
    setRefreshing(true);
    fadeAnim.setValue(0);
    slideAnim.setValue(20);
    fetchData();
  };

  // 날짜 포맷
  const formatScheduleDate = (dateStr: string) => {
    const date = new Date(dateStr);
    const today = new Date();
    const currentYear = today.getFullYear();
    const currentMonth = today.getMonth();
    
    const scheduleYear = date.getFullYear();
    const scheduleMonth = date.getMonth();
    const isCurrentYear = scheduleYear === currentYear;
    const isCurrentMonth = isCurrentYear && scheduleMonth === currentMonth;
    
    const weekdays = ['일', '월', '화', '수', '목', '금', '토'];
    return {
      day: date.getDate(),
      weekday: weekdays[date.getDay()],
      year: scheduleYear,
      month: scheduleMonth + 1,
      isCurrentYear,
      isCurrentMonth,
    };
  };

  if (loading) {
    return (
      <SafeAreaView style={styles.container} edges={[]}>
        <Header />
        <View style={styles.loadingContainer}>
          <ActivityIndicator size="large" color={colors.primary} />
        </View>
      </SafeAreaView>
    );
  }

  return (
    <SafeAreaView style={styles.container} edges={[]}>
      {/* 공통 헤더 */}
      <Header />

      <ScrollView
        style={styles.scrollView}
        refreshControl={
          <RefreshControl refreshing={refreshing} onRefresh={onRefresh} />
        }
        showsVerticalScrollIndicator={false}
        contentContainerStyle={styles.scrollContent}
      >
        {/* 히어로 섹션 - bg-gradient-to-br from-primary to-primary-dark py-12 px-4 */}
        <Animated.View style={[styles.heroSection, { opacity: fadeAnim }]}>
          <View style={styles.heroOverlay} />
          <View style={styles.heroContent}>
            <Text style={styles.heroTitle}>fromis_9</Text>
            <Text style={styles.heroSubtitle}>프로미스나인</Text>
            <Text style={styles.heroText}>
              인사드리겠습니다. 둘, 셋!{'\n'}
              이제는 약속해 소중히 간직해,{'\n'}
              당신의 아이돌로 성장하겠습니다!
            </Text>
          </View>
          {/* 장식 원 */}
          <View style={[styles.decorCircle, styles.decorCircle1]} />
          <View style={[styles.decorCircle, styles.decorCircle2]} />
        </Animated.View>

        {/* 멤버 섹션 */}
        <Animated.View 
          style={[
            styles.section,
            { opacity: fadeAnim, transform: [{ translateY: slideAnim }] }
          ]}
        >
          <View style={styles.sectionHeader}>
            <Text style={styles.sectionTitle}>멤버</Text>
            <TouchableOpacity style={styles.moreButton}>
              <Text style={styles.moreButtonText}>전체보기</Text>
              <ChevronRight size={16} color={colors.primary} />
            </TouchableOpacity>
          </View>
          <View style={styles.membersGrid}>
            {members.slice(0, 5).map((member) => (
              <View key={member.id} style={styles.memberItem}>
                <View style={styles.memberImageContainer}>
                  {member.image_url && (
                    <Image
                      source={{ uri: member.image_url }}
                      style={styles.memberImage}
                    />
                  )}
                </View>
                <Text style={styles.memberName} numberOfLines={1}>
                  {member.name}
                </Text>
              </View>
            ))}
          </View>
        </Animated.View>

        {/* 앨범 섹션 */}
        <Animated.View 
          style={[
            styles.section, 
            { opacity: fadeAnim, transform: [{ translateY: slideAnim }] }
          ]}
        >
          <View style={styles.sectionHeader}>
            <Text style={styles.sectionTitle}>앨범</Text>
            <TouchableOpacity 
              style={styles.moreButton}
              onPress={() => navigation.navigate('AlbumList')}
            >
              <Text style={styles.moreButtonText}>전체보기</Text>
              <ChevronRight size={16} color={colors.primary} />
            </TouchableOpacity>
          </View>
          <View style={styles.albumsGrid}>
            {albums.map((album) => (
              <TouchableOpacity
                key={album.id}
                style={styles.albumCard}
                onPress={() => navigation.navigate('AlbumDetail', { name: album.folder_name })}
                activeOpacity={0.98}
              >
                <View style={styles.albumImageContainer}>
                  <Image
                    source={{ uri: album.cover_thumb_url || album.cover_medium_url }}
                    style={styles.albumImage}
                  />
                </View>
                <View style={styles.albumInfo}>
                  <Text style={styles.albumTitle} numberOfLines={1}>
                    {album.title}
                  </Text>
                  <Text style={styles.albumYear}>
                    {album.release_date?.slice(0, 4)}
                  </Text>
                </View>
              </TouchableOpacity>
            ))}
          </View>
        </Animated.View>

        {/* 일정 섹션 */}
        <Animated.View 
          style={[
            styles.scheduleSection,
            { opacity: fadeAnim, transform: [{ translateY: slideAnim }] }
          ]}
        >
          <View style={styles.sectionHeader}>
            <Text style={styles.sectionTitle}>다가오는 일정</Text>
            <TouchableOpacity style={styles.moreButton}>
              <Text style={styles.moreButtonText}>전체보기</Text>
              <ChevronRight size={16} color={colors.primary} />
            </TouchableOpacity>
          </View>
          {schedules.length > 0 ? (
            <View style={styles.schedulesList}>
              {schedules.map((schedule) => {
                const dateInfo = formatScheduleDate(schedule.date);
                const memberList = schedule.member_names 
                  ? schedule.member_names.split(',').map(n => n.trim()).filter(Boolean)
                  : [];
                
                return (
                  <TouchableOpacity
                    key={schedule.id} 
                    style={styles.scheduleCard}
                    activeOpacity={0.98}
                  >
                    {/* 날짜 영역 */}
                    <View style={styles.scheduleDateContainer}>
                      {!dateInfo.isCurrentYear && (
                        <Text style={styles.scheduleDateExtra}>
                          {dateInfo.year}.{dateInfo.month}
                        </Text>
                      )}
                      {dateInfo.isCurrentYear && !dateInfo.isCurrentMonth && (
                        <Text style={styles.scheduleDateExtra}>
                          {dateInfo.month}월
                        </Text>
                      )}
                      <Text style={styles.scheduleDay}>{dateInfo.day}</Text>
                      <Text style={styles.scheduleWeekday}>{dateInfo.weekday}</Text>
                    </View>
                    
                    {/* 세로 구분선 */}
                    <View style={styles.scheduleDivider} />
                    
                    {/* 내용 영역 */}
                    <View style={styles.scheduleContent}>
                      <Text style={styles.scheduleTitle} numberOfLines={2}>
                        {schedule.title}
                      </Text>
                      <View style={styles.scheduleMeta}>
                        {schedule.time && (
                          <View style={styles.scheduleMetaItem}>
                            <Clock size={12} color="#9CA3AF" />
                            <Text style={styles.scheduleMetaText}>
                              {schedule.time.slice(0, 5)}
                            </Text>
                          </View>
                        )}
                        {schedule.category_name && (
                          <View style={styles.scheduleMetaItem}>
                            <Tag size={12} color="#9CA3AF" />
                            <Text style={styles.scheduleMetaText}>
                              {schedule.category_name}
                            </Text>
                          </View>
                        )}
                      </View>
                      {memberList.length > 0 && (
                        <View style={styles.memberTags}>
                          {(memberList.length >= 5 ? ['프로미스나인'] : memberList).map((name, i) => (
                            <View key={i} style={styles.memberTag}>
                              <Text style={styles.memberTagText}>{name}</Text>
                            </View>
                          ))}
                        </View>
                      )}
                    </View>
                  </TouchableOpacity>
                );
              })}
            </View>
          ) : (
            <View style={styles.emptySchedule}>
              <Text style={styles.emptyText}>다가오는 일정이 없습니다</Text>
            </View>
          )}
        </Animated.View>
      </ScrollView>
    </SafeAreaView>
  );
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    backgroundColor: BG_GRAY,
  },
  loadingContainer: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
    backgroundColor: BG_GRAY,
  },
  
  // 헤더
  header: {
    backgroundColor: '#FFFFFF',
    paddingVertical: 14,
    alignItems: 'center',
    shadowColor: '#000',
    shadowOffset: { width: 0, height: 1 },
    shadowOpacity: 0.05,
    shadowRadius: 2,
    elevation: 2,
  },
  headerTitle: {
    fontSize: 20,
    fontWeight: 'bold',
    color: colors.primary,
  },
  
  scrollView: {
    flex: 1,
  },
  scrollContent: {
    paddingBottom: 0,
  },
  
  // 히어로 섹션
  heroSection: {
    backgroundColor: colors.primary,
    paddingVertical: 48,
    paddingHorizontal: 16,
    position: 'relative',
    overflow: 'hidden',
  },
  heroOverlay: {
    ...StyleSheet.absoluteFillObject,
    backgroundColor: 'rgba(0,0,0,0.1)',
  },
  heroContent: {
    alignItems: 'center',
  },
  heroTitle: {
    fontSize: 30,
    fontWeight: 'bold',
    color: '#FFFFFF',
    marginBottom: 4,
  },
  heroSubtitle: {
    fontSize: 18,
    color: '#FFFFFF',
    fontWeight: '300',
    marginBottom: 12,
  },
  heroText: {
    fontSize: 14,
    color: 'rgba(255,255,255,0.8)',
    textAlign: 'center',
    lineHeight: 22,
  },
  decorCircle: {
    position: 'absolute',
    borderRadius: 999,
    backgroundColor: 'rgba(255,255,255,0.1)',
  },
  decorCircle1: {
    width: 128,
    height: 128,
    right: -32,
    top: -32,
  },
  decorCircle2: {
    width: 96,
    height: 96,
    left: -24,
    bottom: -24,
    backgroundColor: 'rgba(255,255,255,0.05)',
  },
  
  // 섹션 공통
  section: {
    paddingHorizontal: 16,
    paddingVertical: 24,
  },
  scheduleSection: {
    paddingHorizontal: 16,
    paddingTop: 16,
    paddingBottom: 16,
  },
  sectionHeader: {
    flexDirection: 'row',
    justifyContent: 'space-between',
    alignItems: 'center',
    marginBottom: 16,
  },
  sectionTitle: {
    fontSize: 18,
    fontWeight: 'bold',
    color: '#111827',
  },
  moreButton: {
    flexDirection: 'row',
    alignItems: 'center',
    gap: 4,
  },
  moreButtonText: {
    fontSize: 14,
    color: colors.primary,
  },
  
  // 멤버 섹션
  membersGrid: {
    flexDirection: 'row',
    justifyContent: 'space-between',
  },
  memberItem: {
    alignItems: 'center',
    width: '18%',
  },
  memberImageContainer: {
    width: 56,
    height: 56,
    borderRadius: 28,
    overflow: 'hidden',
    backgroundColor: '#E5E7EB',
    marginBottom: 4,
  },
  memberImage: {
    width: '100%',
    height: '100%',
  },
  memberName: {
    fontSize: 12,
    fontWeight: '500',
    color: '#111827',
    textAlign: 'center',
  },
  
  // 앨범 섹션
  albumsGrid: {
    flexDirection: 'row',
    gap: 12,
  },
  albumCard: {
    flex: 1,
    backgroundColor: '#FFFFFF',
    borderRadius: 12,
    overflow: 'hidden',
    shadowColor: '#000',
    shadowOffset: { width: 0, height: 1 },
    shadowOpacity: 0.05,
    shadowRadius: 3,
    elevation: 2,
  },
  albumImageContainer: {
    aspectRatio: 1,
    backgroundColor: '#E5E7EB',
  },
  albumImage: {
    width: '100%',
    height: '100%',
  },
  albumInfo: {
    padding: 12,
  },
  albumTitle: {
    fontSize: 14,
    fontWeight: '500',
    color: '#111827',
  },
  albumYear: {
    fontSize: 12,
    color: '#9CA3AF',
    marginTop: 2,
  },
  
  // 일정 섹션
  schedulesList: {
    gap: 12,
  },
  scheduleCard: {
    flexDirection: 'row',
    backgroundColor: '#FFFFFF',
    padding: 16,
    borderRadius: 12,
    borderWidth: 1,
    borderColor: '#F3F4F6',
    shadowColor: '#000',
    shadowOffset: { width: 0, height: 1 },
    shadowOpacity: 0.03,
    shadowRadius: 2,
    elevation: 1,
  },
  scheduleDateContainer: {
    alignItems: 'center',
    justifyContent: 'center',
    minWidth: 50,
  },
  scheduleDateExtra: {
    fontSize: 10,
    color: '#9CA3AF',
    fontWeight: '500',
  },
  scheduleDay: {
    fontSize: 24,
    fontWeight: 'bold',
    color: colors.primary,
  },
  scheduleWeekday: {
    fontSize: 12,
    color: '#9CA3AF',
    fontWeight: '500',
  },
  scheduleDivider: {
    width: 1,
    backgroundColor: '#F3F4F6',
    marginHorizontal: 16,
  },
  scheduleContent: {
    flex: 1,
  },
  scheduleTitle: {
    fontSize: 14,
    fontWeight: '600',
    color: '#1F2937',
    lineHeight: 20,
  },
  scheduleMeta: {
    flexDirection: 'row',
    gap: 12,
    marginTop: 8,
  },
  scheduleMetaItem: {
    flexDirection: 'row',
    alignItems: 'center',
    gap: 4,
  },
  scheduleMetaText: {
    fontSize: 12,
    color: '#9CA3AF',
  },
  memberTags: {
    flexDirection: 'row',
    flexWrap: 'wrap',
    gap: 4,
    marginTop: 8,
  },
  memberTag: {
    backgroundColor: colors.primary + '1A',
    paddingHorizontal: 8,
    paddingVertical: 2,
    borderRadius: 10,
  },
  memberTagText: {
    fontSize: 10,
    color: colors.primary,
    fontWeight: '500',
  },
  emptySchedule: {
    paddingVertical: 32,
    alignItems: 'center',
  },
  emptyText: {
    color: '#9CA3AF',
  },
});