import { Ionicons } from '@expo/vector-icons';
import { useRouter } from 'expo-router';
import { ActivityIndicator, Pressable, ScrollView, StyleSheet, Switch, Text, View } from 'react-native';
import { SafeAreaView } from 'react-native-safe-area-context';
import { useNotificationSettings } from '../../src/hooks';
import { colors , spacing } from '../../src/theme';

/* ===================== 子组件：顶部导航 ===================== */

function Header({ onBack }: { onBack: () => void }) {
  return (
    <View style={styles.header}>
      <Pressable style={styles.headerBtn} onPress={onBack} hitSlop={8}>
        <Ionicons name="chevron-back" size={24} color={colors.textPrimary} />
      </Pressable>
      <Text style={styles.headerTitle}>消息通知</Text>
      <View style={styles.headerBtn} />
    </View>
  );
}

/* ===================== 页面 ===================== */

export default function NotificationSettingsScreen() {
  const router = useRouter();
  const { settings, loading, error, refresh, toggle, updatingId } = useNotificationSettings();

  return (
    <SafeAreaView style={styles.safeArea} edges={['top']}>
      <Header onBack={() => router.back()} />

      {loading ? (
        <View style={styles.stateBox}>
          <ActivityIndicator size="large" color={colors.primary} />
        </View>
      ) : error ? (
        <View style={styles.stateBox}>
          <Text style={styles.stateText}>加载失败，请重试</Text>
          <Pressable style={styles.retryBtn} onPress={refresh}>
            <Text style={styles.retryText}>重试</Text>
          </Pressable>
        </View>
      ) : settings.length === 0 ? (
        <View style={styles.stateBox}>
          <Ionicons name="notifications-off-outline" size={48} color={colors.textHint} />
          <Text style={styles.stateText}>暂无通知设置项</Text>
        </View>
      ) : (
        <ScrollView
          style={styles.scroll}
          contentContainerStyle={styles.content}
          showsVerticalScrollIndicator={false}
        >
          <Text style={styles.tip}>
            选择你希望接收的通知类型，重要通知建议保持开启。
          </Text>

          <View style={styles.card}>
            {settings.map((item, index) => {
              const isLast = index === settings.length - 1;
              return (
                <View key={item.id} style={[styles.row, isLast && styles.rowLast]}>
                  <View style={styles.rowBody}>
                    <Text style={styles.rowTitle}>{item.title}</Text>
                    <Text style={styles.rowDesc}>{item.description}</Text>
                  </View>
                  <Switch
                    value={item.enabled}
                    onValueChange={(next) => toggle(item.id, next)}
                    disabled={updatingId === item.id}
                    trackColor={{ false: colors.border, true: colors.primaryBorder }}
                    thumbColor={item.enabled ? colors.primary : colors.white}
                  />
                </View>
              );
            })}
          </View>
        </ScrollView>
      )}
    </SafeAreaView>
  );
}

const styles = StyleSheet.create({
  safeArea: {
    flex: 1,
    backgroundColor: colors.pageBg,
  },
  header: {
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'space-between',
    paddingHorizontal: spacing.card,
    height: 48,
    backgroundColor: colors.white,
    borderBottomWidth: 1,
    borderBottomColor: colors.borderLight,
  },
  headerBtn: {
    width: 40,
    height: 40,
    alignItems: 'center',
    justifyContent: 'center',
  },
  headerTitle: {
    fontSize: 17,
    fontWeight: '700',
    color: colors.textPrimary,
  },
  scroll: {
    flex: 1,
  },
  content: {
    padding: spacing.card,
    paddingBottom: 24,
  },
  tip: {
    fontSize: 12,
    lineHeight: 17,
    color: colors.textSecondary,
    marginBottom: 10,
    paddingHorizontal: 4,
  },
  card: {
    backgroundColor: colors.white,
    borderRadius: spacing.card,
    paddingHorizontal: spacing.card,
  },
  row: {
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'space-between',
    paddingVertical: 14,
    borderBottomWidth: 1,
    borderBottomColor: colors.borderLight,
  },
  rowLast: {
    borderBottomWidth: 0,
  },
  rowBody: {
    flex: 1,
    marginRight: 12,
  },
  rowTitle: {
    fontSize: 15,
    fontWeight: '600',
    color: colors.textPrimary,
  },
  rowDesc: {
    marginTop: 3,
    fontSize: 12,
    lineHeight: 16,
    color: colors.textSecondary,
  },
  stateBox: {
    flex: 1,
    alignItems: 'center',
    justifyContent: 'center',
  },
  stateText: {
    marginTop: 12,
    fontSize: 14,
    color: colors.textSecondary,
  },
  retryBtn: {
    marginTop: 16,
    paddingHorizontal: 24,
    paddingVertical: spacing.card,
    borderRadius: 18,
    backgroundColor: colors.primaryBtn,
  },
  retryText: {
    fontSize: 13,
    fontWeight: '600',
    color: colors.white,
  },
});