import { Ionicons } from '@expo/vector-icons';
import { useFocusEffect, useRouter } from 'expo-router';
import { useCallback, useState } from 'react';
import {
  ActivityIndicator,
  Pressable,
  ScrollView,
  StyleSheet,
  Text,
  View,
} from 'react-native';
import { SafeAreaView } from 'react-native-safe-area-context';
import { useLegalData, useLegalMembership } from '../src/hooks';
import { colors , spacing } from '../src/theme';
import type { LegalFAQ, LegalPlan, LegalService, LegalTemplate } from '../src/types';

/* ===================== 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}>阿布阿诺法律服务</Text>
      <View style={styles.headerBtn} />
    </View>
  );
}

/* ===================== 子组件：品牌卡片 ===================== */

function BrandCard({ name, company, slogan, logo }: { name: string; company: string; slogan: string; logo: string }) {
  return (
    <View style={styles.brandCard}>
      <View style={styles.brandLogo}>
        <Text style={styles.brandLogoText}>{logo}</Text>
      </View>
      <View style={styles.brandBody}>
        <Text style={styles.brandName}>{name}</Text>
        <Text style={styles.brandCompany}>{company}</Text>
        <Text style={styles.brandSlogan}>{slogan}</Text>
      </View>
    </View>
  );
}

/* ===================== 子组件：服务入口 ===================== */

function ServiceCard({
  service,
  isUnlocked,
  onPress,
}: {
  service: LegalService;
  /** 会员服务是否已解锁（已开通会员） */
  isUnlocked: boolean;
  onPress: () => void;
}) {
  const isMember = service.type === 'member';
  return (
    <Pressable
      style={[
        styles.serviceCard,
        isMember ? styles.serviceCardMember : styles.serviceCardFree,
      ]}
      onPress={onPress}
    >
      <View style={styles.serviceIconWrap}>
        <Ionicons name={service.icon as keyof typeof Ionicons.glyphMap} size={22} color={isMember ? colors.action : colors.primary} />
      </View>
      <View style={styles.serviceBody}>
        <View style={styles.serviceTitleRow}>
          <Text style={styles.serviceTitle}>{service.title}</Text>
          {isMember && (
            <View style={styles.memberTag}>
              <Text style={styles.memberTagText}>{isUnlocked ? '已开通' : '会员'}</Text>
            </View>
          )}
        </View>
        <Text style={styles.serviceDesc}>{service.description}</Text>
      </View>
      <Ionicons name="chevron-forward" size={18} color={colors.textHint} />
    </Pressable>
  );
}

/* ===================== 子组件：FAQ 卡片 ===================== */

function FAQItem({ faq }: { faq: LegalFAQ }) {
  const [expanded, setExpanded] = useState(false);
  return (
    <Pressable style={styles.faqItem} onPress={() => setExpanded((v) => !v)}>
      <View style={styles.faqRow}>
        <Text style={styles.faqQ}>{faq.question}</Text>
        <Ionicons name={expanded ? 'chevron-up' : 'chevron-down'} size={18} color={colors.textHint} />
      </View>
      {expanded && <Text style={styles.faqA}>{faq.answer}</Text>}
    </Pressable>
  );
}

/* ===================== 子组件：模板卡片 ===================== */

function TemplateCard({ template }: { template: LegalTemplate }) {
  return (
    <View style={styles.templateCard}>
      <Ionicons name={template.icon as keyof typeof Ionicons.glyphMap} size={22} color={colors.primary} />
      <View style={styles.templateBody}>
        <Text style={styles.templateName}>{template.name}</Text>
        <Text style={styles.templateDesc}>{template.description}</Text>
      </View>
    </View>
  );
}

/* ===================== 子组件：会员套餐 ===================== */

function PlanCard({ plan, onPress }: { plan: LegalPlan; onPress?: () => void }) {
  return (
    <Pressable
      style={({ pressed }) => [
        styles.planCard,
        plan.recommended && styles.planCardRecommended,
        pressed && styles.planPressed,
      ]}
      onPress={onPress}
      disabled={!onPress}
    >
      {plan.recommended && (
        <View style={styles.recommendedTag}>
          <Text style={styles.recommendedText}>推荐</Text>
        </View>
      )}
      <Text style={styles.planName}>{plan.name}</Text>
      <View style={styles.planPriceRow}>
        <Text style={styles.planCurrency}>¥</Text>
        <Text style={styles.planPrice}>{plan.price}</Text>
        <Text style={styles.planPeriod}>{plan.period}</Text>
      </View>
      <View style={styles.benefits}>
        {plan.benefits.map((benefit, idx) => (
          <View key={idx} style={styles.benefitRow}>
            <Ionicons name="checkmark-circle" size={14} color={colors.success} />
            <Text style={styles.benefitText}>{benefit}</Text>
          </View>
        ))}
      </View>
      <View style={styles.planCtaRow}>
        <Text style={styles.planCtaText}>立即开通</Text>
        <Ionicons name="chevron-forward" size={16} color={colors.action} />
      </View>
    </Pressable>
  );
}

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

export default function LegalScreen() {
  const router = useRouter();
  const { brand, services, faqs, templates, plans, loading, error, refresh } = useLegalData();
  const { membership, refresh: refreshMembership } = useLegalMembership();

  // 返回本页时刷新会员态（支付成功后需即时反映）
  useFocusEffect(
    useCallback(() => {
      refreshMembership();
    }, [refreshMembership]),
  );

  const freeServices = services.filter((s) => s.type === 'free');
  const memberServices = services.filter((s) => s.type === 'member');

  const handleServicePress = (service: LegalService) => {
    if (service.action === 'chat') {
      router.push('/legal/chat');
    } else if (service.action === 'templates') {
      router.push('/legal/templates');
    } else if (service.action === 'faq') {
      router.push('/legal/faq');
    } else if (service.action === 'upgrade') {
      // 已开通会员 → 进入服务使用页（权益兑现）；未开通 → 引导开通
      if (membership) {
        router.push(`/legal/service?id=${service.id}`);
      } else {
        router.push('/legal/upgrade');
      }
    }
  };

  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>
      ) : (
        <ScrollView
          style={styles.scroll}
          contentContainerStyle={styles.content}
          showsVerticalScrollIndicator={false}
        >
          {brand && (
            <BrandCard
              name={brand.name}
              company={brand.company}
              slogan={brand.slogan}
              logo={brand.logo}
            />
          )}

          {/* 下面两个网格此前没有空态保护，同文件的模板/FAQ/套餐三处都做了 —— 统一补齐 */}
          <SectionTitle title="免费法律援助" />
          {freeServices.length === 0 ? (
            <EmptyGridHint text="暂无免费法律服务" />
          ) : (
            <View style={styles.serviceGrid}>
              {freeServices.map((service) => (
                <ServiceCard
                  key={service.id}
                  service={service}
                  isUnlocked={false}
                  onPress={() => handleServicePress(service)}
                />
              ))}
            </View>
          )}

          <SectionTitle title="会员法律服务" />
          {memberServices.length === 0 ? (
            <EmptyGridHint text="暂无会员法律服务" />
          ) : (
            <View style={styles.serviceGrid}>
              {memberServices.map((service) => (
                <ServiceCard
                  key={service.id}
                  service={service}
                  isUnlocked={Boolean(membership)}
                  onPress={() => handleServicePress(service)}
                />
              ))}
            </View>
          )}

          {templates.length > 0 && (
            <>
              <SectionTitle title="文书模板" />
              <View style={styles.templateGrid}>
                {templates.map((template) => (
                  <TemplateCard key={template.id} template={template} />
                ))}
              </View>
            </>
          )}

          {faqs.length > 0 && (
            <>
              <SectionTitle title="常见问题速查" />
              <View style={styles.faqCard}>
                {faqs.map((faq) => (
                  <FAQItem key={faq.id} faq={faq} />
                ))}
              </View>
            </>
          )}

          {plans.length > 0 && (
            <>
              <SectionTitle title="会员套餐" />
              {membership && (
                <View style={styles.memberBanner}>
                  <Ionicons name="shield-checkmark" size={16} color={colors.action} />
                  <Text style={styles.memberBannerText}>
                    您已开通{membership.planName}，可畅享会员专属服务
                  </Text>
                </View>
              )}
              <View style={styles.planGrid}>
                {plans.map((plan) => (
                  <PlanCard
                    key={plan.id}
                    plan={plan}
                    onPress={() => router.push(`/legal/checkout?planId=${plan.id}`)}
                  />
                ))}
              </View>
            </>
          )}

          <Pressable style={styles.consultBtn} onPress={() => router.push('/legal/chat')}>
            <Ionicons name="chatbubble-ellipses-outline" size={18} color={colors.white} />
            <Text style={styles.consultText}>开始法律咨询</Text>
          </Pressable>
        </ScrollView>
      )}
    </SafeAreaView>
  );
}

/* ===================== 公共子组件 ===================== */

/** 服务网格的空态提示（区块级，不占满整屏） */
function EmptyGridHint({ text }: { text: string }) {
  return (
    <View style={styles.emptyHint}>
      <Ionicons name="documents-outline" size={28} color={colors.textHint} />
      <Text style={styles.emptyHintText}>{text}</Text>
    </View>
  );
}

function SectionTitle({ title }: { title: string }) {
  return (
    <View style={styles.sectionHeader}>
      <View style={styles.sectionBar} />
      <Text style={styles.sectionTitle}>{title}</Text>
    </View>
  );
}

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,
  },
  brandCard: {
    flexDirection: 'row',
    alignItems: 'center',
    backgroundColor: colors.primaryLight,
    borderRadius: spacing.card,
    padding: spacing.card,
    marginBottom: 8,
    borderWidth: 1,
    borderColor: colors.primaryBorder,
  },
  brandLogo: {
    width: 56,
    height: 56,
    borderRadius: 28,
    backgroundColor: colors.white,
    alignItems: 'center',
    justifyContent: 'center',
  },
  brandLogoText: {
    fontSize: 28,
  },
  brandBody: {
    flex: 1,
    marginLeft: 12,
  },
  brandName: {
    fontSize: 18,
    fontWeight: '700',
    color: colors.primaryText,
  },
  brandCompany: {
    marginTop: 2,
    fontSize: 12,
    color: colors.textSecondary,
  },
  brandSlogan: {
    marginTop: 4,
    fontSize: 13,
    fontWeight: '600',
    color: colors.primary,
  },
  sectionHeader: {
    flexDirection: 'row',
    alignItems: 'center',
    marginTop: 20,
    marginBottom: 10,
  },
  sectionBar: {
    width: 4,
    height: 16,
    borderRadius: 2,
    backgroundColor: colors.primary,
    marginRight: 8,
  },
  sectionTitle: {
    fontSize: 16,
    fontWeight: '700',
    color: colors.textPrimary,
  },
  serviceGrid: {
    gap: 8,
  },
  emptyHint: {
    backgroundColor: colors.surface,
    borderRadius: spacing.card,
    padding: spacing.card,
    alignItems: 'center',
    gap: 8,
  },
  emptyHintText: {
    fontSize: 13,
    color: colors.textSecondary,
  },
  serviceCard: {
    flexDirection: 'row',
    alignItems: 'center',
    padding: spacing.card,
    borderRadius: spacing.card,
    backgroundColor: colors.white,
  },
  serviceCardFree: {
    borderLeftWidth: 3,
    borderLeftColor: colors.primary,
  },
  serviceCardMember: {
    borderLeftWidth: 3,
    borderLeftColor: colors.action,
  },
  serviceIconWrap: {
    width: 40,
    height: 40,
    borderRadius: 20,
    backgroundColor: colors.pageBg,
    alignItems: 'center',
    justifyContent: 'center',
  },
  serviceBody: {
    flex: 1,
    marginLeft: 12,
    marginRight: 8,
  },
  serviceTitleRow: {
    flexDirection: 'row',
    alignItems: 'center',
    gap: 6,
  },
  serviceTitle: {
    fontSize: 15,
    fontWeight: '700',
    color: colors.textPrimary,
  },
  memberTag: {
    paddingHorizontal: 6,
    paddingVertical: 2,
    borderRadius: 4,
    backgroundColor: colors.actionLight,
  },
  memberTagText: {
    fontSize: 10,
    fontWeight: '700',
    color: colors.actionText,
  },
  serviceDesc: {
    marginTop: 2,
    fontSize: 12,
    color: colors.textSecondary,
    lineHeight: 17,
  },
  templateGrid: {
    gap: 8,
  },
  templateCard: {
    flexDirection: 'row',
    alignItems: 'center',
    padding: spacing.card,
    borderRadius: spacing.card,
    backgroundColor: colors.white,
  },
  templateBody: {
    flex: 1,
    marginLeft: 12,
  },
  templateName: {
    fontSize: 14,
    fontWeight: '700',
    color: colors.textPrimary,
  },
  templateDesc: {
    marginTop: 2,
    fontSize: 12,
    color: colors.textSecondary,
  },
  faqCard: {
    backgroundColor: colors.white,
    borderRadius: spacing.card,
    paddingHorizontal: spacing.card,
  },
  faqItem: {
    paddingVertical: 12,
    borderBottomWidth: 1,
    borderBottomColor: colors.borderLight,
  },
  faqRow: {
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'space-between',
  },
  faqQ: {
    flex: 1,
    fontSize: 14,
    fontWeight: '600',
    color: colors.textPrimary,
    marginRight: 8,
  },
  faqA: {
    marginTop: 8,
    fontSize: 13,
    lineHeight: 19,
    color: colors.textSecondary,
  },
  planGrid: {
    flexDirection: 'row',
    gap: 8,
  },
  planCard: {
    flex: 1,
    padding: spacing.card,
    borderRadius: spacing.card,
    backgroundColor: colors.white,
    borderWidth: 1,
    borderColor: colors.border,
  },
  planPressed: {
    opacity: 0.85,
  },
  planCtaRow: {
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'flex-end',
    marginTop: 12,
    gap: 2,
  },
  planCtaText: {
    fontSize: 13,
    fontWeight: '700',
    color: colors.action,
  },
  memberBanner: {
    flexDirection: 'row',
    alignItems: 'center',
    gap: 6,
    paddingHorizontal: spacing.card,
    paddingVertical: spacing.card,
    borderRadius: spacing.card,
    backgroundColor: colors.actionLight,
    borderWidth: 1,
    borderColor: colors.action,
    marginBottom: 8,
  },
  memberBannerText: {
    flex: 1,
    fontSize: 13,
    fontWeight: '600',
    color: colors.actionText,
  },
  planCardRecommended: {
    borderColor: colors.action,
    backgroundColor: colors.actionLight,
  },
  recommendedTag: {
    alignSelf: 'flex-start',
    paddingHorizontal: 6,
    paddingVertical: 2,
    borderRadius: 4,
    backgroundColor: colors.action,
    marginBottom: 8,
  },
  recommendedText: {
    fontSize: 10,
    fontWeight: '700',
    color: colors.white,
  },
  planName: {
    fontSize: 15,
    fontWeight: '700',
    color: colors.textPrimary,
  },
  planPriceRow: {
    flexDirection: 'row',
    alignItems: 'baseline',
    marginTop: 8,
    marginBottom: 10,
  },
  planCurrency: {
    fontSize: 14,
    fontWeight: '700',
    color: colors.actionText,
  },
  planPrice: {
    fontSize: 28,
    fontWeight: '700',
    color: colors.actionText,
  },
  planPeriod: {
    fontSize: 13,
    color: colors.textSecondary,
  },
  benefits: {
    gap: 6,
  },
  benefitRow: {
    flexDirection: 'row',
    alignItems: 'center',
    gap: 6,
  },
  benefitText: {
    fontSize: 12,
    color: colors.textSecondary,
  },
  consultBtn: {
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'center',
    gap: 8,
    marginTop: 20,
    height: 48,
    borderRadius: spacing.card,
    backgroundColor: colors.primaryBtn,
  },
  consultText: {
    fontSize: 15,
    fontWeight: '700',
    color: colors.white,
  },
  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,
  },
});