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

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

function Header({ progress, onBack }: { progress: 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.headerTitle}>霍兰德测评</Text>
        <Text style={styles.headerSub}>{progress}</Text>
      </View>
      <View style={styles.headerBtn} />
    </View>
  );
}

/* ===================== 子组件：六维分布条 ===================== */

function DimensionBars({ dimensions }: { dimensions: HollandDimension[] }) {
  return (
    <View style={styles.dimCard}>
      <Text style={styles.dimTitle}>当前六维分布</Text>
      <View style={styles.dimGrid}>
        {dimensions.map((d) => (
          <View key={d.type} style={styles.dimRow}>
            <Text style={styles.dimType}>{d.type}</Text>
            <Text style={styles.dimName}>{d.name}</Text>
            <View style={styles.dimTrack}>
              <View
                style={[
                  styles.dimFill,
                  { width: `${d.percent}%`, backgroundColor: hollandTypeColors[d.type] },
                ]}
              />
            </View>
            <Text style={styles.dimScore}>{d.score}</Text>
          </View>
        ))}
      </View>
    </View>
  );
}

/* ===================== 子组件：选项 ===================== */

function OptionButton({
  option,
  selected,
  onPress,
}: {
  option: HollandOption;
  selected: boolean;
  onPress: () => void;
}) {
  return (
    <Pressable style={[styles.option, selected && styles.optionActive]} onPress={onPress}>
      <Text style={[styles.optionText, selected && styles.optionTextActive]}>{option.label}</Text>
      {selected && <Ionicons name="checkmark-circle" size={20} color={colors.primary} />}
    </Pressable>
  );
}

/* ===================== 子组件：四态 ===================== */

function Loading() {
  return (
    <View style={styles.center}>
      <ActivityIndicator size="large" color={colors.primary} />
      <Text style={styles.tip}>正在加载测评…</Text>
    </View>
  );
}

function ErrorState({ onRetry }: { onRetry: () => void }) {
  return (
    <View style={styles.center}>
      <Ionicons name="help-circle-outline" size={40} color={colors.textHint} />
      <Text style={styles.tip}>测评加载失败</Text>
      <Pressable style={styles.retryBtn} onPress={onRetry} hitSlop={6}>
        <Text style={styles.retryText}>点击重试</Text>
      </Pressable>
    </View>
  );
}

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

export default function HollandQuestionScreen() {
  const router = useRouter();
  const { assessment, loading, error, refresh, submit } = useHollandAssessment();
  const [selectedValue, setSelectedValue] = useState<number | null>(null);
  const [localIndex, setLocalIndex] = useState(0);

  if (loading) {
    return (
      <SafeAreaView style={styles.container} edges={['top']}>
        <Header progress="加载中…" onBack={() => router.back()} />
        <Loading />
      </SafeAreaView>
    );
  }

  if (error || !assessment) {
    return (
      <SafeAreaView style={styles.container} edges={['top']}>
        <Header progress="" onBack={() => router.back()} />
        <ErrorState onRetry={refresh} />
      </SafeAreaView>
    );
  }

  const currentQuestion = Math.min(
    assessment.currentQuestionIndex + 1 + localIndex,
    assessment.totalQuestions,
  );
  const progressText = `第 ${currentQuestion}/${assessment.totalQuestions} 题`;

  const handleNext = async () => {
    if (selectedValue == null) return;
    await submit(assessment.question.id, selectedValue);
    setSelectedValue(null);
    const nextIndex = localIndex + 1;
    setLocalIndex(nextIndex);
    if (nextIndex >= 3 || assessment.currentQuestionIndex + 1 >= assessment.totalQuestions) {
      router.push('/holland-result');
    }
  };

  return (
    <SafeAreaView style={styles.container} edges={['top']}>
      <Header progress={progressText} onBack={() => router.back()} />
      <ScrollView contentContainerStyle={styles.body} showsVerticalScrollIndicator={false}>
        <DimensionBars dimensions={assessment.dimensions} />

        <View style={styles.questionCard}>
          <Text style={styles.questionTitle}>请根据你的兴趣程度选择</Text>
          <Text style={styles.questionText}>{assessment.question.text}</Text>
        </View>

        <View style={styles.options}>
          {assessment.options.map((option) => (
            <OptionButton
              key={option.value}
              option={option}
              selected={selectedValue === option.value}
              onPress={() => setSelectedValue(option.value)}
            />
          ))}
        </View>

        <View style={styles.footer}>
          <Pressable style={[styles.navBtn, styles.navBtnPrev]} onPress={() => router.back()}>
            <Text style={styles.navBtnPrevText}>上一题</Text>
          </Pressable>
          <Pressable
            style={[
              styles.navBtn,
              styles.navBtnNext,
              selectedValue == null && styles.navBtnNextDisabled,
            ]}
            onPress={handleNext}
            disabled={selectedValue == null}
          >
            <Text style={styles.navBtnNextText}>下一题</Text>
          </Pressable>
        </View>
      </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' },
  headerTitle: { fontSize: 17, fontWeight: '700', color: colors.textPrimary },
  headerSub: { fontSize: 12, color: colors.textHint, marginTop: 2 },
  body: { padding: 8, paddingBottom: 32 },
  dimCard: {
    backgroundColor: colors.white,
    borderRadius: 8,
    padding: 8,
    marginBottom: 8,
    borderWidth: 1,
    borderColor: colors.borderLight,
  },
  dimTitle: { fontSize: 15, fontWeight: '700', color: colors.textPrimary, marginBottom: 14 },
  dimGrid: { flexDirection: 'row', flexWrap: 'wrap', gap: 10 },
  dimRow: {
    width: '47%',
    flexDirection: 'row',
    alignItems: 'center',
  },
  dimType: {
    width: 18,
    fontSize: 13,
    fontWeight: '800',
    color: colors.textPrimary,
  },
  dimName: {
    width: 36,
    fontSize: 12,
    color: colors.textSecondary,
  },
  dimTrack: {
    flex: 1,
    height: 6,
    borderRadius: 3,
    backgroundColor: colors.borderLight,
    overflow: 'hidden',
  },
  dimFill: { height: 6, borderRadius: 3 },
  dimScore: {
    width: 28,
    fontSize: 12,
    fontWeight: '700',
    color: colors.textPrimary,
    textAlign: 'right',
  },
  questionCard: {
    backgroundColor: colors.white,
    borderRadius: 8,
    padding: 8,
    marginBottom: 8,
    borderWidth: 1,
    borderColor: colors.borderLight,
    alignItems: 'center',
  },
  questionTitle: { fontSize: 13, color: colors.textHint, marginBottom: 16 },
  questionText: {
    fontSize: 20,
    fontWeight: '700',
    color: colors.textPrimary,
    textAlign: 'center',
    lineHeight: 28,
  },
  options: { gap: 8, marginBottom: 20 },
  option: {
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'space-between',
    backgroundColor: colors.white,
    borderRadius: 8,
    paddingVertical: 8,
    paddingHorizontal: 8,
    borderWidth: 1,
    borderColor: colors.borderLight,
  },
  optionActive: {
    backgroundColor: colors.primaryLight,
    borderColor: colors.primary,
  },
  optionText: { fontSize: 15, color: colors.textPrimary },
  optionTextActive: { fontWeight: '700', color: colors.primaryText },
  footer: {
    flexDirection: 'row',
    gap: 12,
  },
  navBtn: {
    flex: 1,
    borderRadius: 12,
    paddingVertical: 14,
    alignItems: 'center',
  },
  navBtnPrev: {
    backgroundColor: colors.white,
    borderWidth: 1,
    borderColor: colors.border,
  },
  navBtnPrevText: { fontSize: 15, fontWeight: '600', color: colors.textPrimary },
  navBtnNext: { backgroundColor: colors.primaryBtn },
  navBtnNextDisabled: { backgroundColor: colors.textDisabled },
  navBtnNextText: { fontSize: 15, fontWeight: '700', color: colors.white },
  center: {
    flex: 1,
    alignItems: 'center',
    justifyContent: 'center',
    paddingHorizontal: 40,
    gap: 12,
  },
  tip: { fontSize: 14, color: colors.textSecondary },
  retryBtn: {
    paddingHorizontal: 18,
    paddingVertical: 8,
    borderRadius: 16,
    backgroundColor: colors.primaryLight,
  },
  retryText: { fontSize: 13, fontWeight: '600', color: colors.primaryText },
});