import React from 'react';
import { Share, StyleSheet, Text, View, Pressable, Linking } from 'react-native';
import { NativeStackScreenProps } from '@react-navigation/native-stack';
import { Icon } from '../../../components/Icon';

import { Card, ScreenShell, Button } from '../../../components';
import { ServicesStackParamList } from '../../../navigation/types';
import { useTheme, fontFamily } from '../../../theme';
import { useSchemes } from '../hooks/useSchemes';
import { Accordion } from '../components/Accordion';

type Props = NativeStackScreenProps<ServicesStackParamList, 'SchemeDetails'>;

export default function SchemeDetailScreen({ route, navigation }: Props) {
  const { schemeId } = route.params;
  const theme = useTheme();
  const { schemes, bookmarks, toggleBookmark } = useSchemes();

  const scheme = schemes.find((s) => s.id === schemeId);
  const isBookmarked = bookmarks.includes(schemeId);

  if (!scheme) {
    return (
      <ScreenShell title="Not Found">
        <View style={styles.errorContainer}>
          <Text style={{ color: theme.colors.textPrimary }}>Scheme not found.</Text>
        </View>
      </ScreenShell>
    );
  }

  const handleShare = async () => {
    try {
      await Share.share({
        message: `${scheme.title}\n\n${scheme.description}\n\nLearn more on BankCBS!`,
        title: scheme.title,
      });
    } catch (error) {
      console.error('Error sharing scheme', error);
    }
  };

  const handleApply = async () => {
    if (scheme.isNew || scheme.type === 'GOVT_SCHEME') {
      navigation.navigate('SchemeEnrollment', { schemeId });
    } else if (scheme.applyUrl) {
      const supported = await Linking.canOpenURL(scheme.applyUrl);
      if (supported) {
        await Linking.openURL(scheme.applyUrl);
      }
    }
  };

  const rightContent = (
    <View style={styles.headerActions}>
      <Pressable onPress={handleShare} style={[styles.actionBtn, { backgroundColor: theme.colors.surfaceMuted }]}>
        <Icon name="share-social-outline" size={20} color={theme.colors.textPrimary} />
      </Pressable>
      <Pressable 
        onPress={() => toggleBookmark(schemeId)} 
        style={[styles.actionBtn, { backgroundColor: isBookmarked ? theme.tint(theme.colors.primary, 0.08) : theme.colors.surfaceMuted }]}
      >
        <Icon 
          name={isBookmarked ? 'bookmark' : 'bookmark-outline'} 
          size={20} 
          color={isBookmarked ? theme.colors.primary : theme.colors.textPrimary} 
        />
      </Pressable>
    </View>
  );

  return (
    <ScreenShell 
      title="Details" 
      subtitle={scheme.type.replace('_', ' ')}
      rightContent={rightContent}
    >
      <View style={styles.container}>
        <View style={styles.metaRow}>
          <View style={[styles.typeBadge, { backgroundColor: theme.tint(theme.colors.primary, 0.07) }]}>
            <Text style={[styles.typeText, { color: theme.colors.primary }]}>{scheme.type.replace('_', ' ')}</Text>
          </View>
          <View style={[styles.categoryBadge, { backgroundColor: theme.colors.surfaceMuted }]}>
            <Text style={[styles.categoryText, { color: theme.colors.textSecondary }]}>{scheme.category}</Text>
          </View>
        </View>

        <Text style={[styles.title, { color: theme.colors.textPrimary }]}>{scheme.title}</Text>
        
        <Card variant="glass" style={styles.overviewCard}>
          <Text style={[styles.description, { color: theme.colors.textSecondary }]}>
            {scheme.description}
          </Text>
        </Card>

        <View style={styles.section}>
          <Text style={[styles.sectionTitle, { color: theme.colors.textPrimary }]}>About the Scheme</Text>
          <Text style={[styles.contentText, { color: theme.colors.textPrimary }]}>
            {scheme.content}
          </Text>
        </View>

        {scheme.benefits && (
          <View style={styles.section}>
            <Text style={[styles.sectionTitle, { color: theme.colors.textPrimary }]}>Key Benefits</Text>
            {scheme.benefits.map((benefit, idx) => (
              <View key={idx} style={styles.listRow}>
                <Icon name="checkmark-circle" size={18} color={theme.colors.success} />
                <Text style={[styles.listText, { color: theme.colors.textSecondary }]}>{benefit}</Text>
              </View>
            ))}
          </View>
        )}

        {scheme.eligibility && (
          <View style={styles.section}>
            <Text style={[styles.sectionTitle, { color: theme.colors.textPrimary }]}>Eligibility Criteria</Text>
            {scheme.eligibility.map((criterion, idx) => (
              <View key={idx} style={styles.listRow}>
                <Icon name="information-circle-outline" size={18} color={theme.colors.primary} />
                <Text style={[styles.listText, { color: theme.colors.textSecondary }]}>{criterion}</Text>
              </View>
            ))}
          </View>
        )}

        {scheme.premiumInfo && (
          <View style={styles.section}>
            <Text style={[styles.sectionTitle, { color: theme.colors.textPrimary }]}>Premium & Contributions</Text>
            <View style={[styles.highlightCard, { backgroundColor: theme.colors.surfaceMuted }]}>
              <Text style={[styles.highlightText, { color: theme.colors.textPrimary }]}>{scheme.premiumInfo}</Text>
            </View>
          </View>
        )}

        {scheme.faqs && scheme.faqs.length > 0 && (
          <View style={styles.section}>
            <Text style={[styles.sectionTitle, { color: theme.colors.textPrimary }]}>Frequently Asked Questions</Text>
            {scheme.faqs.map((faq, idx) => (
              <Accordion key={idx} title={faq.question}>
                <Text style={[styles.faqAnswer, { color: theme.colors.textSecondary }]}>
                  {faq.answer}
                </Text>
              </Accordion>
            ))}
          </View>
        )}

        {scheme.applyUrl && (
          <View style={styles.footerAction}>
            <Button 
               title={scheme.type === 'GOVT_SCHEME' ? "Enroll Now" : "Apply Now"} 
               onPress={handleApply}
            />
            <Text style={[styles.disclaimer, { color: theme.colors.textMuted }]}>
              {scheme.type === 'GOVT_SCHEME' 
                ? "* Enrolling digitally will trigger an OTP verification sent to your registered mobile."
                : "* Clicking Apply Now will redirect you to the official government portal."}
            </Text>
          </View>
        )}
      </View>
    </ScreenShell>
  );
}

const styles = StyleSheet.create({
  container: {
    paddingHorizontal: 16,
    paddingBottom: 40,
  },
  headerActions: {
    flexDirection: 'row',
    gap: 8,
  },
  actionBtn: {
    width: 40,
    height: 40,
    borderRadius: 12,
    alignItems: 'center',
    justifyContent: 'center',
  },
  metaRow: {
    flexDirection: 'row',
    gap: 8,
    alignItems: 'center',
    marginBottom: 12,
  },
  typeBadge: {
    paddingHorizontal: 10,
    paddingVertical: 4,
    borderRadius: 8,
  },
  typeText: {
    fontSize: 11,
    fontFamily: fontFamily.bold,
    letterSpacing: 0.1,
  },
  categoryBadge: {
    paddingHorizontal: 10,
    paddingVertical: 4,
    borderRadius: 8,
  },
  categoryText: {
    fontSize: 11,
    fontFamily: fontFamily.bold,
  },
  title: {
    fontSize: 24,
    fontFamily: fontFamily.bold,
    lineHeight: 30,
    marginBottom: 16,
  },
  overviewCard: {
    padding: 16,
    marginBottom: 24,
  },
  description: {
    fontSize: 15,
    lineHeight: 22,
    fontFamily: fontFamily.medium,
  },
  section: {
    marginBottom: 28,
  },
  sectionTitle: {
    fontSize: 18,
    fontFamily: fontFamily.bold,
    marginBottom: 12,
  },
  contentText: {
    fontSize: 16,
    lineHeight: 24,
  },
  listRow: {
    flexDirection: 'row',
    gap: 12,
    marginBottom: 10,
    alignItems: 'flex-start',
  },
  listText: {
    fontSize: 15,
    lineHeight: 20,
    flex: 1,
  },
  highlightCard: {
    padding: 16,
    borderRadius: 12,
  },
  highlightText: {
    fontSize: 15,
    fontFamily: fontFamily.semibold,
  },
  faqAnswer: {
    fontSize: 14,
    lineHeight: 20,
  },
  footerAction: {
    marginTop: 10,
    gap: 12,
  },
  disclaimer: {
    fontSize: 11,
    textAlign: 'center',
    fontStyle: 'italic',
  },
  errorContainer: {
    padding: 20,
    alignItems: 'center',
  },
});