import React from 'react';
import { RefreshControl, ScrollView, StyleSheet, Text, View } from 'react-native';
import type { NativeStackScreenProps } from '@react-navigation/native-stack';
import Ionicons from '@react-native-vector-icons/ionicons';

import type { LoanStackParamList } from '../../../navigation/types';
import { Button, Card, EmptyState, Loader, ScreenShell } from '../../../components';
import { useTheme } from '../../../theme';
import { formatCurrency, formatDate, formatCompactCurrency } from '../../../utils/formatters';
import { useLoanDashboard } from '../hooks/useLoanDashboard';
import { LoanSummaryHero } from '../components/LoanSummaryHero';
import { LoanAccountCard } from '../components/LoanAccountCard';
import { LoanFilterChip } from '../components/LoanFilterChip';

import { LoanNotificationItem } from '../components/LoanNotificationItem';
import { useGetLoanNotificationsQuery } from '../services/loanApi';

type Props = NativeStackScreenProps<LoanStackParamList, 'LoanDashboard'>;

export default function LoanDashboardScreen({ navigation }: Props) {
  const theme = useTheme();
  const {
    activeLoans,
    applications,
    totalOutstanding,
    nextEmi,
    summary,
    unreadNotifications,
    isLoading,
    isError,
    refreshing,
    onRefresh,
  } = useLoanDashboard();

  // Mock notifications for demonstration on dashboard
  const { data: notifications } = useGetLoanNotificationsQuery();
  const recentNotifications = (notifications ?? []).slice(0, 2);

  return (
    <ScreenShell title="Loan Management" subtitle="Manage active loans and apply for new ones" scrollable={false}>
      <ScrollView
        showsVerticalScrollIndicator={false}
        contentContainerStyle={styles.scrollContent}
        refreshControl={
          <RefreshControl
            refreshing={refreshing}
            onRefresh={onRefresh}
            tintColor={theme.colors.primary}
            colors={[theme.colors.primary]}
          />
        }
      >
        {/* Hero Summary */}
        <LoanSummaryHero totalOutstanding={totalOutstanding} nextEmi={nextEmi} summary={summary} />

        {/* Notifications Section */}
        {recentNotifications.length > 0 && (
          <View style={styles.loanSection}>
            <View style={styles.sectionHeaderRow}>
              <Text style={[styles.sectionTitle, { color: theme.colors.textPrimary }]}>What's new</Text>
              {unreadNotifications > 0 && (
                <View style={[styles.unreadBadge, { backgroundColor: theme.colors.primary }]}>
                  <Text style={styles.unreadCount}>{unreadNotifications}</Text>
                </View>
              )}
            </View>
            <Card style={styles.notificationCard}>
              {recentNotifications.map((notif, index) => (
                <View key={notif.id}>
                  <LoanNotificationItem notification={notif} />
                  {index < recentNotifications.length - 1 && (
                    <View style={[styles.divider, { backgroundColor: theme.colors.cardBorder }]} />
                  )}
                </View>
              ))}
            </Card>
          </View>
        )}

        {/* Quick Actions */}
        <Card style={styles.actionCard}>
          <View style={styles.sectionHeader}>
            <Text style={[styles.sectionTitle, { color: theme.colors.textPrimary }]}>Quick actions</Text>
            <Text style={[styles.sectionSubtitle, { color: theme.colors.textSecondary }]}>
              Apply for a new loan, calculate EMI, or manage payments
            </Text>
          </View>
          <View style={styles.actionGrid}>
            <View style={styles.actionRow}>
              <View style={styles.actionCol}>
                <Button
                  title="Apply Loan"
                  onPress={() => navigation.navigate('LoanTypesListing')}
                  leftAccessory={<Ionicons name="add-circle-outline" size={18} color={theme.colors.white} />}
                />
              </View>
              <View style={styles.actionCol}>
                <Button
                  title="EMI Calculator"
                  variant="secondary"
                  onPress={() => navigation.navigate('LoanCalculator', {})}
                  leftAccessory={<Ionicons name="calculator-outline" size={18} color={theme.colors.textPrimary} />}
                />
              </View>
            </View>
            <View style={styles.actionRow}>
              <View style={styles.actionCol}>
                <Button
                  title="Track Application"
                  variant="secondary"
                  onPress={() => navigation.navigate('LoanTracking')}
                  leftAccessory={<Ionicons name="locate-outline" size={18} color={theme.colors.textPrimary} />}
                />
              </View>
              <View style={styles.actionCol}>
                <Button
                  title="Payment History"
                  variant="secondary"
                  onPress={() => navigation.navigate('LoanHistory')}
                  leftAccessory={<Ionicons name="time-outline" size={18} color={theme.colors.textPrimary} />}
                />
              </View>
            </View>
            <Button
              title="Documents"
              variant="secondary"
              onPress={() => navigation.navigate('LoanDocuments', {})}
              leftAccessory={<Ionicons name="document-text-outline" size={18} color={theme.colors.textPrimary} />}
            />
          </View>
        </Card>

        {/* Active Loans */}
        <View style={styles.loanSection}>
          <View style={styles.sectionHeaderRow}>
            <View style={styles.sectionHeaderCopy}>
              <Text style={[styles.sectionTitle, { color: theme.colors.textPrimary }]}>Active loans</Text>
              <Text style={[styles.sectionSubtitle, { color: theme.colors.textSecondary }]}>
                {activeLoans.length} loan{activeLoans.length !== 1 ? 's' : ''} in your portfolio
              </Text>
            </View>
          </View>

          {isLoading && !activeLoans.length ? (
            <Card><Loader /></Card>
          ) : null}

          {isError && !activeLoans.length ? (
            <EmptyState
              title="Unable to load loans"
              description="Please pull to refresh or try again in a moment."
              actionLabel="Refresh"
              onAction={onRefresh}
            />
          ) : null}

          {!isLoading && !isError && !activeLoans.length ? (
            <EmptyState
              title="No active loans"
              description="Apply for a loan to finance your dreams with competitive interest rates."
              actionLabel="Apply for Loan"
              onAction={() => navigation.navigate('LoanTypesListing')}
            />
          ) : null}

          {activeLoans.map((loan) => (
            <LoanAccountCard
              key={loan.id}
              loan={loan}
              onPress={() => navigation.navigate('ActiveLoanDetails', { loanId: loan.id })}
            />
          ))}
        </View>

        {/* Recent Applications */}
        {applications.length > 0 && (
          <View style={styles.loanSection}>
            <Text style={[styles.sectionTitle, { color: theme.colors.textPrimary }]}>Recent applications</Text>
            {applications.map((app) => (
              <Card key={app.id} style={styles.applicationCard}>
                <View style={styles.appHeader}>
                  <View style={styles.appHeaderLeft}>
                    <Text style={[styles.appType, { color: theme.colors.textPrimary }]}>{app.type}</Text>
                    <Text style={[styles.appAmount, { color: theme.colors.textSecondary }]}>
                      {formatCurrency(app.amount)} · {formatDate(app.appliedDate)}
                    </Text>
                  </View>
                  <View
                    style={[
                      styles.appStatusBadge,
                      {
                        backgroundColor: app.status === 'Approved' ? '#10B98114' :
                          app.status === 'Rejected' ? '#EF444414' : `${theme.colors.primary}14`,
                      },
                    ]}
                  >
                    <Text
                      style={[
                        styles.appStatusText,
                        {
                          color: app.status === 'Approved' ? '#10B981' :
                            app.status === 'Rejected' ? '#EF4444' : theme.colors.primary,
                        },
                      ]}
                    >
                      {app.status}
                    </Text>
                  </View>
                </View>
              </Card>
            ))}
          </View>
        )}

        <View style={styles.bottomSpacer} />
      </ScrollView>
    </ScreenShell>
  );
}

const styles = StyleSheet.create({
  scrollContent: { gap: 18, paddingBottom: 24 },
  actionCard: { gap: 16 },
  sectionHeader: { gap: 4 },
  sectionTitle: { fontSize: 18, fontWeight: '800' },
  sectionSubtitle: { fontSize: 13, lineHeight: 18 },
  actionGrid: { gap: 12 },
  actionRow: { flexDirection: 'row', gap: 12 },
  actionCol: { flex: 1 },
  loanSection: { gap: 14 },
  sectionHeaderRow: { flexDirection: 'row', alignItems: 'center', justifyContent: 'space-between' },
  sectionHeaderCopy: { flex: 1, gap: 4 },
  applicationCard: { gap: 8 },
  unreadBadge: {
    paddingHorizontal: 8,
    paddingVertical: 2,
    borderRadius: 8,
    marginLeft: 8,
  },
  unreadCount: {
    color: '#FFF',
    fontSize: 12,
    fontWeight: '800',
  },
  notificationCard: { padding: 4, gap: 0 },
  divider: { height: 1, marginHorizontal: 12 },
  appHeader: { flexDirection: 'row', justifyContent: 'space-between', alignItems: 'center' },
  appHeaderLeft: { gap: 2 },
  appType: { fontSize: 15, fontWeight: '700' },
  appAmount: { fontSize: 12, fontWeight: '500' },
  appStatusBadge: { paddingHorizontal: 10, paddingVertical: 5, borderRadius: 999 },
  appStatusText: { fontSize: 12, fontWeight: '700' },
  bottomSpacer: { height: 60 },
});