import React, { useEffect, useRef, useState } from 'react';
import { View, Text, StyleSheet, TouchableOpacity, Dimensions, Platform, Alert, Image } from 'react-native';
import { useRouter } from 'expo-router';
import * as WebBrowser from 'expo-web-browser';
import { Trans, useTranslation } from 'react-i18next';
import { SafeAreaView } from 'react-native-safe-area-context';
import { setConsentAccepted, getConsentAccepted } from '../../src/storage/appStorage';
import { fetchLegalLinks } from '@/src/services/legalApi';
import { getOnboardingCompleted } from '@/src/storage/appStorage';
import { API_BASE_URL } from '@/src/constants/env';

// 导入 SVG 组件
import FlowersBg from '../../assets/images/index/flowers_endbg.svg';
import WelcomeBtn from '../../assets/images/index/welcome_btn.svg';

const { width, height } = Dimensions.get('window');

export default function SplashScreen() {
  const router = useRouter();
  const { t } = useTranslation();
  const [showConsent, setShowConsent] = useState(false);
  const [links, setLinks] = useState<{ privacy?: string; terms?: string }>({});
  const [linksLoading, setLinksLoading] = useState(false);
  const mountedRef = useRef(true);

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

  useEffect(() => {
    return () => {
      mountedRef.current = false;
    };
  }, []);

  const checkConsent = async () => {
    const accepted = await getConsentAccepted();
    setShowConsent(!accepted);
    if (accepted) {
      // 已同意协议则直接分发到目标页，避免先回到 /（index）再二次跳转导致“闪一下”
      const completed = await getOnboardingCompleted();
      if (completed) {
        router.replace('/(app)/home');
      } else {
        router.replace('/(onboarding)/onboarding');
      }
    }
  };

  const handleAgree = async () => {
    await setConsentAccepted(true);
    setShowConsent(false);
    // 跳转到 onboarding 流程
    router.replace('/(onboarding)/onboarding');
  };

  const openLink = async (url: string) => {
    try {
      await WebBrowser.openBrowserAsync(url);
    } catch (error) {
      Alert.alert(t('common.error'), t('common.openLinkError'));
    }
  };

  async function refreshLegalLinks(): Promise<{ privacy?: string; terms?: string }> {
    if (mountedRef.current) setLinksLoading(true);
    try {
      const res = await fetchLegalLinks();
      const next = { privacy: res.privacyPolicyUrl, terms: res.termsOfUseUrl };
      if (mountedRef.current) setLinks(next);
      return next;
    } catch (e) {
      // 不阻塞主流程：失败时不崩溃，链接入口仍可点（会提示）
      if (__DEV__) console.log('[LegalLinks] 拉取失败（splash）:', e);
      if (mountedRef.current) setLinks({});
      return {};
    } finally {
      if (mountedRef.current) setLinksLoading(false);
    }
  }

  async function handleOpenLegal(type: 'privacy' | 'terms') {
    const currentUrl = type === 'privacy' ? links.privacy : links.terms;
    if (currentUrl) {
      await openLink(currentUrl);
      return;
    }

    // 链接还没拿到/拉取失败：点击时主动再拉一次，避免“点了没反应”
    const next = await refreshLegalLinks();
    const nextUrl = type === 'privacy' ? next.privacy : next.terms;
    if (nextUrl) {
      await openLink(nextUrl);
      return;
    }

    const msg =
      typeof __DEV__ !== 'undefined' && __DEV__
        ? t('consent.linkUnavailableDev', { baseUrl: API_BASE_URL })
        : t('consent.linkUnavailable');
    Alert.alert(t('common.notice'), msg);
  }

  // 拉取协议链接（由后端按语言下发；默认 EN）
  useEffect(() => {
    void refreshLegalLinks();
  }, []);

  const bgDecorationTop = 363;
  const bgDecorationHeight = height * 0.6;
  const contentTop = bgDecorationTop + (bgDecorationHeight * 0.25);

  return (
    <View style={styles.container}>
      {/* 中间的背景装饰 SVG (现在放在上面，作为上层) */}
      <View style={[styles.bgDecorationContainer, { top: bgDecorationTop }]}>
        <FlowersBg width={width + 10} height={bgDecorationHeight} />
      </View>

      {/* 顶部的花图片 (现在放在下面，作为下层) */}
      <View style={styles.topImageContainer}>
        <Image
          source={require('../../assets/images/index/index_flowers.png')}
          style={styles.topImage}
          resizeMode="contain"
        />
      </View>

      {/* 文案内容 */}
      <View style={[styles.contentContainer, { position: 'absolute', top: contentTop }]}>
        <Text style={styles.titleText}>
          {t('consent.title')}
          {'\n'}
          {t('consent.subtitle')}
        </Text>
      </View>

      <SafeAreaView style={styles.bottomContainer} edges={['bottom']}>
        {showConsent && (
          <>
            <TouchableOpacity
              onPress={handleAgree}
              activeOpacity={0.8}
              style={styles.buttonWrapper}
              accessibilityRole="button"
              accessibilityLabel={t('consent.agree')}
            >
              <WelcomeBtn width={87} height={57} />
            </TouchableOpacity>

            <Text style={styles.noticeText}>
              <Trans
                i18nKey="consent.noticeRich"
                values={{
                  privacyLabel: t('consent.privacy'),
                  termsLabel: t('consent.terms'),
                  privacySuffix: !links.privacy && linksLoading ? t('consent.linkLoadingSuffix') : '',
                  termsSuffix: !links.terms && linksLoading ? t('consent.linkLoadingSuffix') : '',
                }}
                components={{
                  privacy: (
                    <Text
                      style={[styles.noticeLinkText, !links.privacy && styles.noticeLinkTextDisabled]}
                      onPress={() => void handleOpenLegal('privacy')}
                      suppressHighlighting
                    />
                  ),
                  terms: (
                    <Text
                      style={[styles.noticeLinkText, !links.terms && styles.noticeLinkTextDisabled]}
                      onPress={() => void handleOpenLegal('terms')}
                      suppressHighlighting
                    />
                  ),
                }}
              />
            </Text>
          </>
        )}
      </SafeAreaView>
    </View>
  );
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    backgroundColor: '#F5D3B5', // 匹配 Figma 背景色
    alignItems: 'center',
  },
  topImageContainer: {
    marginTop: 60,
    zIndex: 1, // 降低层级
  },
  topImage: {
    width: 308,
    height: 354,
  },
  bgDecorationContainer: {
    position: 'absolute',
    left: -3,
    zIndex: 2, // 提高层级，使其覆盖在图片之上
  },
  contentContainer: {
    alignItems: 'center',
    zIndex: 3,
  },
  titleText: {
    fontSize: 30,
    lineHeight: 42,
    color: '#772F00', // 匹配 Figma 文字颜色
    textAlign: 'center',
    fontWeight: '600',
    fontFamily: Platform.OS === 'ios' ? 'STIX Two Text' : 'serif',
  },
  bottomContainer: {
    position: 'absolute',
    bottom: 60,
    width: '100%',
    alignItems: 'center',
    zIndex: 4,
  },
  buttonWrapper: {
    marginBottom: 40,
  },
  noticeText: {
    marginTop: 10,
    paddingHorizontal: 28,
    fontSize: 12,
    lineHeight: 16,
    textAlign: 'center',
    color: 'rgba(119, 47, 0, 0.45)',
  },
  noticeLinkText: {
    fontSize: 12,
    // 颜色区分：协议链接更醒目
    color: 'rgba(119, 47, 0, 0.75)',
    textDecorationLine: 'underline',
    fontWeight: '600',
  },
  noticeLinkTextDisabled: {
    opacity: 0.55,
  },
});
