import { Ionicons } from '@expo/vector-icons';
import { useRouter } from 'expo-router';
import { useState } from 'react';
import {
  ActivityIndicator,
  Alert,
  Pressable,
  ScrollView,
  StyleSheet,
  Text,
  View,
} from 'react-native';
import { SafeAreaView } from 'react-native-safe-area-context';
import { useTalentRecommendation } from '../../src/hooks';
import { colors } from '../../src/theme';
import type { TalentCandidate, TalentRecommendationTab } from '../../src/types';

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

function Header({ companyName, onBack }: { companyName: string; 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>
      <View style={styles.headerCenter}>
        <Text style={styles.headerCompany}>{companyName}</Text>
        <Text style={styles.headerTitle}>人才推荐</Text>
      </View>
      <View style={styles.headerActions}>
        <Pressable style={styles.headerActionBtn} hitSlop={6}>
          <Ionicons name="search-outline" size={22} color={colors.textPrimary} />
        </Pressable>
        <Pressable style={styles.headerActionBtn} hitSlop={6}>
          <Ionicons name="options-outline" size={22} color={colors.textPrimary} />
        </Pressable>
      </View>
    </View>
  );
}

/* ===================== 子组件：Tab 栏 ===================== */

function TabBar({
  tabs,
  active,
  onChange,
}: {
  tabs: TalentRecommendationTab[];
  active: string;
  onChange: (key: string) => void;
}) {
  return (
    <View style={styles.tabBar}>
      {tabs.map((tab) => {
        const isActive = tab.key === active;
        return (
          <Pressable key={tab.key} style={styles.tabItem} onPress={() => onChange(tab.key)}>
            <Text style={[styles.tabLabel, isActive && styles.tabLabelActive]}>
              {tab.label}
              <Text style={[styles.tabCount, isActive && styles.tabCountActive]}>({tab.count})</Text>
            </Text>
            <View style={[styles.tabIndicator, isActive && styles.tabIndicatorActive]} />
          </Pressable>
        );
      })}
    </View>
  );
}

/* ===================== 子组件：今日推荐头部 ===================== */

function TodayHeader({ count, onReport }: { count: number; onReport: () => void }) {
  return (
    <View style={styles.todayHeader}>
      <View>
        <Text style={styles.todayTitle}>今日为你推荐</Text>
        <View style={styles.todayCountRow}>
          <Text style={styles.todayCount}>{count}</Text>
          <Text style={styles.todayUnit}>位优质候选人</Text>
        </View>
      </View>
      <Pressable style={styles.reportBtn} onPress={onReport}>
        <Text style={styles.reportBtnText}>查看人才市场报告</Text>
        <Ionicons name="chevron-forward" size={14} color={colors.primary} />
      </Pressable>
    </View>
  );
}

/* ===================== 子组件：候选人卡片 ===================== */

function CandidateCard({ candidate }: { candidate: TalentCandidate }) {
  const router = useRouter();
  return (
    <View style={styles.candidateCard}>
      <View style={styles.candidateHeader}>
        <View style={styles.avatar}>
          <Text style={styles.avatarText}>{candidate.avatar}</Text>
        </View>
        <View style={styles.candidateInfo}>
          <View style={styles.nameRow}>
            <Text style={styles.candidateName}>{candidate.name}</Text>
            <View style={styles.matchTag}>
              <Text style={styles.matchTagText}>{candidate.matchPercent}%</Text>
            </View>
          </View>
          <Text style={styles.candidateTitle}>{candidate.title}</Text>
          <Text style={styles.candidateMeta}>
            {candidate.age}岁 · {candidate.school}
          </Text>
          <Text style={styles.candidateSalary}>{candidate.expectedSalary}</Text>
        </View>
      </View>

      <View style={styles.scoreRow}>
        <Text style={styles.scoreLabel}>综合评分</Text>
        <Text style={styles.scoreValue}>{candidate.overallScore}</Text>
        <Text style={styles.percentileText}>超越 {candidate.percentile}% 候选人</Text>
      </View>

      <View style={styles.tagRow}>
        {candidate.tags.map((tag) => (
          <View key={tag} style={styles.tag}>
            <Text style={styles.tagText}>{tag}</Text>
          </View>
        ))}
      </View>

      <View style={styles.candidateActions}>
        <Pressable style={styles.chatBtn} onPress={() => router.navigate('/enterprise-chat')}>
          <Text style={styles.chatBtnText}>发起沟通</Text>
        </Pressable>
        <Pressable style={styles.detailBtn} onPress={() => router.push('/candidate-detail?id=' + candidate.id)}>
          <Text style={styles.detailBtnText}>查看详情</Text>
        </Pressable>
      </View>
    </View>
  );
}

/* ===================== 子组件：人才池数据 ===================== */

function TalentPool({ stats, actions, onPressAction }: { stats: { id: string; value: string; label: string }[]; actions: PoolActionItem[]; onPressAction: (action: PoolActionItem) => void }) {
  return (
    <View style={styles.poolCard}>
      <Text style={styles.poolTitle}>人才池数据</Text>
      <View style={styles.poolStatsRow}>
        {stats.map((stat) => (
          <View key={stat.id} style={styles.poolStat}>
            <Text style={styles.poolStatValue}>{stat.value}</Text>
            <Text style={styles.poolStatLabel}>{stat.label}</Text>
          </View>
        ))}
      </View>
      <View style={styles.poolActions}>
        {actions.map((action) => (
          <Pressable key={action.label} style={styles.poolAction} onPress={() => onPressAction(action)}>
            <Ionicons name={action.icon as keyof typeof Ionicons.glyphMap} size={20} color={colors.textSecondary} />
            <Text style={styles.poolActionText}>{action.label}</Text>
          </Pressable>
        ))}
      </View>
    </View>
  );
}

/* ===================== 子组件：空状态 ===================== */

function EmptyState({
  actions,
  dataReference,
  onFilter,
}: {
  actions: string[];
  dataReference: { label: string; value: string }[];
  onFilter: () => void;
}) {
  return (
    <View style={styles.emptyCard}>
      <View style={styles.emptyIconWrap}>
        <Ionicons name="people-outline" size={48} color={colors.primary} />
      </View>
      <Text style={styles.emptyTitle}>暂无匹配候选人</Text>
      <Text style={styles.emptySubtitle}>当前筛选条件下没有较适合的候选人，试试调整筛选条件</Text>
      <Pressable style={styles.emptyBtn} onPress={onFilter} hitSlop={6}>
        <Text style={styles.emptyBtnText}>调整筛选条件</Text>
      </Pressable>

      <View style={styles.actionCard}>
        <View style={styles.actionHeader}>
          <Ionicons name="bulb-outline" size={18} color={colors.compareOrange} />
          <Text style={styles.actionTitle}>推荐操作</Text>
        </View>
        {actions.map((action, index) => (
          <View key={index} style={styles.actionRow}>
            <View style={styles.actionDot} />
            <Text style={styles.actionText}>{action}</Text>
          </View>
        ))}
      </View>

      <View style={styles.dataCard}>
        <Text style={styles.dataTitle}>数据参考</Text>
        {dataReference.map((item, index) => (
          <View key={index} style={styles.dataRow}>
            <Ionicons name="trending-up-outline" size={16} color={colors.success} />
            <Text style={styles.dataText}>
              {item.label}
              <Text style={styles.dataValue}> {item.value}</Text>
            </Text>
          </View>
        ))}
      </View>
    </View>
  );
}

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

/**
 * 人才池快捷操作项：带 route 的跳转目标页，无对应页面的弹「功能开发中」提示。
 * 与 enterprise-chat.tsx 的 QuickActionItem 保持同一约定。
 */
type PoolActionItem = { icon: string; label: string; route?: string };

const POOL_ACTIONS: PoolActionItem[] = [
  { icon: 'mail-outline', label: '批量发邀请' },
  { icon: 'document-text-outline', label: '批量发Offer' },
  { icon: 'calendar-outline', label: '面试评分', route: '/interview-score' },
  { icon: 'notifications-outline', label: '群发通知' },
];

export default function TalentRecommendationScreen() {
  const router = useRouter();
  const { recommendation, loading, error, refresh } = useTalentRecommendation();
  const [activeTab, setActiveTab] = useState('all');

  // 人才池快捷操作分发：有目标路由则跳转，无对应页面则提示「功能开发中」，
  // 避免按钮点击后无任何反馈。与 enterprise-chat.tsx 的 handleQuickAction 同约定。
  const handlePoolAction = (action: PoolActionItem) => {
    if (action.route) {
      router.push(action.route);
    } else {
      Alert.alert('提示', `${action.label}功能开发中，敬请期待`);
    }
  };

  // 以下两处原先绑的是空函数（() => {}），按钮点击后无任何反馈。
  // 暂无对应页面，按项目约定弹「功能开发中」提示。
  const handleReport = () => {
    Alert.alert('提示', '人才市场报告功能开发中，敬请期待');
  };

  const handleFilter = () => {
    Alert.alert('提示', '筛选条件功能开发中，敬请期待');
  };

  if (loading) {
    return (
      <SafeAreaView style={styles.container} edges={['top']}>
        <Header companyName="智联科技" onBack={() => router.back()} />
        <View style={styles.center}>
          <ActivityIndicator size="large" color={colors.primary} />
        </View>
      </SafeAreaView>
    );
  }

  if (error || !recommendation) {
    return (
      <SafeAreaView style={styles.container} edges={['top']}>
        <Header companyName="智联科技" onBack={() => router.back()} />
        <View style={styles.center}>
          <Ionicons name="alert-circle-outline" size={40} color={colors.danger} />
          <Text style={styles.tip}>加载失败</Text>
          <Pressable style={styles.retryBtn} onPress={refresh}>
            <Text style={styles.retryText}>重试</Text>
          </Pressable>
        </View>
      </SafeAreaView>
    );
  }

  return (
    <SafeAreaView style={styles.container} edges={['top', 'bottom']}>
      <Header companyName={recommendation.companyName} onBack={() => router.back()} />
      <TabBar tabs={recommendation.tabs} active={activeTab} onChange={setActiveTab} />
      <ScrollView contentContainerStyle={styles.body} showsVerticalScrollIndicator={false}>
        {recommendation.hasData ? (
          <View>
            <TodayHeader
              count={recommendation.todayCount}
              onReport={handleReport}
            />
            {recommendation.candidates.map((candidate) => (
              <CandidateCard key={candidate.id} candidate={candidate} />
            ))}
            <TalentPool
              stats={recommendation.poolStats}
              actions={POOL_ACTIONS}
              onPressAction={handlePoolAction}
            />
          </View>
        ) : (
          <EmptyState
            actions={recommendation.recommendedActions}
            dataReference={recommendation.dataReference}
            onFilter={handleFilter}
          />
        )}
      </ScrollView>
    </SafeAreaView>
  );
}

const styles = StyleSheet.create({
  container: { flex: 1, backgroundColor: colors.pageBg },
  header: {
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'space-between',
    paddingHorizontal: 12,
    paddingVertical: 12,
    backgroundColor: colors.white,
  },
  headerBtn: { width: 40, alignItems: 'center' },
  headerCenter: { alignItems: 'center' },
  headerCompany: { fontSize: 12, color: colors.textSecondary },
  headerTitle: { fontSize: 17, fontWeight: '700', color: colors.textPrimary, marginTop: 2 },
  headerActions: {
    flexDirection: 'row',
    alignItems: 'center',
  },
  headerActionBtn: {
    width: 36,
    alignItems: 'center',
  },
  tabBar: {
    flexDirection: 'row',
    backgroundColor: colors.white,
    borderBottomWidth: 1,
    borderBottomColor: colors.borderLight,
  },
  tabItem: {
    flex: 1,
    alignItems: 'center',
    paddingTop: 8,
  },
  tabLabel: {
    fontSize: 14,
    color: colors.textSecondary,
    paddingBottom: 8,
  },
  tabLabelActive: {
    color: colors.textPrimary,
    fontWeight: '600',
  },
  tabCount: {
    fontSize: 12,
    color: colors.textHint,
    marginLeft: 2,
  },
  tabCountActive: {
    color: colors.primary,
  },
  tabIndicator: {
    height: 2,
    width: 24,
    borderRadius: 1,
    backgroundColor: 'transparent',
    marginBottom: -1,
  },
  tabIndicatorActive: {
    backgroundColor: colors.primary,
  },
  body: {
    padding: 16,
    paddingBottom: 24,
  },
  center: {
    flex: 1,
    alignItems: 'center',
    justifyContent: 'center',
    gap: 12,
  },
  tip: { fontSize: 14, color: colors.textSecondary },
  retryBtn: {
    marginTop: 8,
    paddingHorizontal: 24,
    paddingVertical: 8,
    borderRadius: 18,
    backgroundColor: colors.primaryBtn,
  },
  retryText: { color: colors.white, fontSize: 13, fontWeight: '600' },
  todayHeader: {
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'space-between',
    marginBottom: 12,
  },
  todayTitle: {
    fontSize: 13,
    color: colors.textSecondary,
  },
  todayCountRow: {
    flexDirection: 'row',
    alignItems: 'baseline',
    marginTop: 2,
  },
  todayCount: {
    fontSize: 28,
    fontWeight: '800',
    color: colors.primary,
  },
  todayUnit: {
    fontSize: 13,
    color: colors.textSecondary,
    marginLeft: 4,
  },
  reportBtn: {
    flexDirection: 'row',
    alignItems: 'center',
    backgroundColor: colors.primaryLight,
    borderRadius: 14,
    paddingHorizontal: 10,
    paddingVertical: 6,
  },
  reportBtnText: {
    fontSize: 12,
    color: colors.primary,
    fontWeight: '600',
    marginRight: 2,
  },
  candidateCard: {
    backgroundColor: colors.white,
    borderRadius: 12,
    padding: 16,
    marginBottom: 12,
  },
  candidateHeader: {
    flexDirection: 'row',
  },
  avatar: {
    width: 52,
    height: 52,
    borderRadius: 26,
    backgroundColor: colors.primaryLight,
    alignItems: 'center',
    justifyContent: 'center',
    marginRight: 12,
  },
  avatarText: {
    fontSize: 20,
    fontWeight: '700',
    color: colors.primary,
  },
  candidateInfo: {
    flex: 1,
  },
  nameRow: {
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'space-between',
  },
  candidateName: {
    fontSize: 16,
    fontWeight: '700',
    color: colors.textPrimary,
  },
  matchTag: {
    backgroundColor: colors.successLight,
    borderRadius: 10,
    paddingHorizontal: 8,
    paddingVertical: 2,
  },
  matchTagText: {
    fontSize: 12,
    fontWeight: '800',
    color: colors.successText,
  },
  candidateTitle: {
    fontSize: 13,
    color: colors.textSecondary,
    marginTop: 2,
  },
  candidateMeta: {
    fontSize: 12,
    color: colors.textHint,
    marginTop: 4,
  },
  candidateSalary: {
    fontSize: 13,
    color: colors.action,
    fontWeight: '600',
    marginTop: 4,
  },
  scoreRow: {
    flexDirection: 'row',
    alignItems: 'center',
    marginTop: 12,
  },
  scoreLabel: {
    fontSize: 13,
    color: colors.textSecondary,
  },
  scoreValue: {
    fontSize: 14,
    fontWeight: '800',
    color: colors.primary,
    marginLeft: 6,
  },
  percentileText: {
    fontSize: 12,
    color: colors.textHint,
    marginLeft: 8,
  },
  tagRow: {
    flexDirection: 'row',
    flexWrap: 'wrap',
    gap: 8,
    marginTop: 10,
  },
  tag: {
    backgroundColor: colors.pageBg,
    borderRadius: 6,
    paddingHorizontal: 8,
    paddingVertical: 3,
  },
  tagText: {
    fontSize: 11,
    color: colors.textSecondary,
  },
  candidateActions: {
    flexDirection: 'row',
    marginTop: 14,
    gap: 10,
  },
  chatBtn: {
    flex: 1,
    backgroundColor: colors.primaryBtn,
    borderRadius: 18,
    paddingVertical: 10,
    alignItems: 'center',
  },
  chatBtnText: {
    color: colors.white,
    fontSize: 14,
    fontWeight: '600',
  },
  detailBtn: {
    flex: 1,
    backgroundColor: colors.primaryLight,
    borderRadius: 18,
    paddingVertical: 10,
    alignItems: 'center',
  },
  detailBtnText: {
    color: colors.primary,
    fontSize: 14,
    fontWeight: '600',
  },
  poolCard: {
    backgroundColor: colors.white,
    borderRadius: 12,
    padding: 16,
    marginTop: 4,
  },
  poolTitle: {
    fontSize: 15,
    fontWeight: '700',
    color: colors.textPrimary,
    marginBottom: 12,
  },
  poolStatsRow: {
    flexDirection: 'row',
    justifyContent: 'space-between',
    marginBottom: 16,
  },
  poolStat: {
    flex: 1,
    alignItems: 'center',
  },
  poolStatValue: {
    fontSize: 18,
    fontWeight: '800',
    color: colors.textPrimary,
  },
  poolStatLabel: {
    fontSize: 11,
    color: colors.textSecondary,
    marginTop: 4,
  },
  poolActions: {
    flexDirection: 'row',
    justifyContent: 'space-around',
    paddingTop: 14,
    borderTopWidth: 1,
    borderTopColor: colors.borderLight,
  },
  poolAction: {
    alignItems: 'center',
  },
  poolActionText: {
    fontSize: 11,
    color: colors.textSecondary,
    marginTop: 4,
  },
  emptyCard: {
    backgroundColor: colors.white,
    borderRadius: 16,
    padding: 28,
    alignItems: 'center',
  },
  emptyIconWrap: {
    width: 88,
    height: 88,
    borderRadius: 44,
    backgroundColor: colors.primaryLight,
    alignItems: 'center',
    justifyContent: 'center',
    marginBottom: 16,
  },
  emptyTitle: {
    fontSize: 18,
    fontWeight: '700',
    color: colors.textPrimary,
    marginBottom: 8,
  },
  emptySubtitle: {
    fontSize: 13,
    color: colors.textSecondary,
    textAlign: 'center',
    marginBottom: 20,
  },
  emptyBtn: {
    backgroundColor: colors.primaryBtn,
    paddingHorizontal: 32,
    paddingVertical: 12,
    borderRadius: 24,
    marginBottom: 24,
  },
  emptyBtnText: {
    color: colors.white,
    fontSize: 15,
    fontWeight: '600',
  },
  actionCard: {
    width: '100%',
    backgroundColor: colors.actionLight,
    borderRadius: 12,
    padding: 16,
    marginBottom: 16,
    alignItems: 'flex-start',
  },
  actionHeader: {
    flexDirection: 'row',
    alignItems: 'center',
    marginBottom: 12,
  },
  actionTitle: {
    fontSize: 14,
    fontWeight: '700',
    color: colors.actionText,
    marginLeft: 8,
  },
  actionRow: {
    flexDirection: 'row',
    alignItems: 'flex-start',
    marginBottom: 10,
  },
  actionDot: {
    width: 6,
    height: 6,
    borderRadius: 3,
    backgroundColor: colors.action,
    marginTop: 6,
    marginRight: 10,
  },
  actionText: {
    flex: 1,
    fontSize: 13,
    color: colors.textPrimary,
    lineHeight: 18,
  },
  dataCard: {
    width: '100%',
    backgroundColor: colors.primaryLight,
    borderRadius: 12,
    padding: 16,
    alignItems: 'flex-start',
  },
  dataTitle: {
    fontSize: 14,
    fontWeight: '700',
    color: colors.primaryText,
    marginBottom: 12,
  },
  dataRow: {
    flexDirection: 'row',
    alignItems: 'flex-start',
    marginBottom: 10,
  },
  dataText: {
    flex: 1,
    fontSize: 13,
    color: colors.textPrimary,
    marginLeft: 10,
    lineHeight: 18,
  },
  dataValue: {
    color: colors.success,
    fontWeight: '700',
  },
});