import React, { useEffect } from 'react';
import { RefreshControl, ScrollView, StyleSheet, Text, View } from 'react-native';
import type { CompositeScreenProps } from '@react-navigation/native';
import type { BottomTabScreenProps } from '@react-navigation/bottom-tabs';
import type { NativeStackScreenProps } from '@react-navigation/native-stack';
import { Icon } from '../../../components/Icon';

import { Button, Card, EmptyState, InfoBanner, Loader, ScreenShell } from '../../../components';
import { useTheme } from '../../../theme';
import { formatCurrency, formatDate, formatTime } from '../../../utils/formatters';
import type { HomeStackParamList, MainTabParamList } from '../../../navigation/types';
import type { ApiError } from '../../../types/api';
import { describeError } from '../../../services/api/cbsErrors';
import { useApiErrorToast } from '../../../hooks/useApiErrorToast';
import { useGetFundTransferDetailQuery } from '../../payments/services/paymentsApi';
import { MODE_LABEL, humaniseReason, statusCopy, toneColors } from '../utils/transferStatus';

type Props = CompositeScreenProps<
  NativeStackScreenProps<HomeStackParamList, 'TransferDetail'>,
  BottomTabScreenProps<MainTabParamList>
>;

const when = (iso: string | null) => (iso ? `${formatDate(iso)}, ${formatTime(iso)}` : null);

export default function TransferDetailScreen({ navigation, route }: Props) {
  const theme = useTheme();
  const showError = useApiErrorToast();
  const { transferId } = route.params;

  // Always fetched fresh on open: reopening the screen is one of the two ways
  // the guide says a pending transfer should re-check its state.
  const { data, isLoading, isFetching, error, refetch } = useGetFundTransferDetailQuery(transferId, {
    refetchOnMountOrArgChange: true,
  });
  const apiError = error as ApiError | undefined;

  // A transfer that is not on this profile: close the detail and say why.
  useEffect(() => {
    if (apiError?.code === 'TRANSACTION_NOT_FOUND') {
      showError(apiError);
      navigation.goBack();
    }
  }, [apiError, navigation, showError]);

  if (isLoading) {
    return (
      <ScreenShell title="Transfer details">
        <Loader />
      </ScreenShell>
    );
  }

  if (!data) {
    const copy = describeError(apiError?.code);

    return (
      <ScreenShell title="Transfer details">
        <EmptyState
          title={copy.title}
          description={apiError?.message || copy.description}
          actionLabel="Try again"
          onAction={refetch}
        />
      </ScreenShell>
    );
  }

  const status = statusCopy(data.status);
  const colors = toneColors(status.tone, theme.colors);
  const showReason =
    Boolean(data.failureReason) && (data.status === 'FAILED' || data.status === 'MANUAL_REVIEW');

  const rows: Array<[string, string | null | undefined]> = [
    ['Paid to', data.payeeName],
    [data.mode === 'P2P' ? 'Mobile' : 'Account', data.payeeDisplay],
    ['IFSC', data.beneficiaryIfsc],
    ['MMID', data.beneficiaryMmid],
    ['Type', `IMPS · ${MODE_LABEL[data.mode] ?? data.mode}`],
    ['Remark', data.remark],
    ['Initiated', when(data.createdAt)],
    ['Last updated', when(data.updatedAt)],
  ];

  return (
    <ScreenShell title="Transfer details" scrollable={false}>
      <ScrollView
        showsVerticalScrollIndicator={false}
        contentContainerStyle={styles.content}
        refreshControl={
          <RefreshControl
            refreshing={isFetching}
            onRefresh={refetch}
            tintColor={theme.colors.primary}
            colors={[theme.colors.primary]}
          />
        }
      >
        {/* ── the outcome ───────────────────────────────────────────────── */}
        <Card style={styles.hero}>
          <View style={[styles.statusIcon, { backgroundColor: colors.surface }]}>
            <Icon name={status.icon} size={30} color={colors.tone} />
          </View>
          <Text style={[theme.text.balance, { color: theme.colors.textPrimary }]}>
            {formatCurrency(data.amount)}
          </Text>
          <View style={[styles.badge, { backgroundColor: colors.surface, borderColor: colors.border }]}>
            {/* `simple` break strategy: Android's default `highQuality` measures
                a custom font as fitting on one line, then wraps it on draw, so
                the last word ("pending") was clipped outside the pill. */}
            <Text
              textBreakStrategy="simple"
              style={[theme.text.bodyStrong, styles.badgeText, { color: colors.tone }]}
            >
              {status.label}
            </Text>
          </View>
          {showReason ? (
            <Text style={[theme.text.body, styles.centre, { color: theme.colors.danger }]}>
              {humaniseReason(data.failureReason as string)}
            </Text>
          ) : null}
        </Card>

        {data.status === 'PENDING_RECONCILIATION' || data.status === 'PROCESSING' ? (
          <InfoBanner
            tone="warning"
            message="Your bank is still confirming this transfer. Don't send it again — refresh in a little while to see the final status."
          />
        ) : null}

        {data.status === 'PENDING_OTP' ? (
          <InfoBanner
            tone="info"
            message="This transfer was never confirmed with an OTP, so no money has left your account."
          />
        ) : null}

        {data.status === 'MANUAL_REVIEW' ? (
          <InfoBanner
            tone="warning"
            message="Your bank is reviewing this transfer. Contact support and quote the reference below if you need help."
          />
        ) : null}

        {/* ── the reference the customer quotes ─────────────────────────── */}
        <Card style={styles.section}>
          <Text style={[theme.text.eyebrow, { color: theme.colors.textMuted }]}>Reference</Text>
          <Text selectable style={[theme.text.code, { color: theme.colors.textPrimary }]}>
            {data.referenceId}
          </Text>
          <Text style={[theme.text.caption, { color: theme.colors.textMuted }]}>
            Press and hold to copy
          </Text>
        </Card>

        <Card style={styles.section}>
          {rows
            .filter(([, value]) => Boolean(value))
            .map(([label, value]) => (
              <View key={label} style={styles.detailRow}>
                <Text style={[theme.text.body, { color: theme.colors.textSecondary }]}>{label}</Text>
                <Text
                  style={[theme.text.bodyStrong, styles.detailValue, { color: theme.colors.textPrimary }]}
                >
                  {value}
                </Text>
              </View>
            ))}
        </Card>

        {status.refreshable ? (
          <Button
            title={isFetching ? 'Checking…' : 'Refresh status'}
            variant="secondary"
            onPress={refetch}
            disabled={isFetching}
          />
        ) : null}

        {data.status === 'MANUAL_REVIEW' || data.status === 'FAILED' ? (
          <Button
            title="Get help"
            variant="ghost"
            onPress={() => navigation.navigate('Profile', { screen: 'HelpSupport' })}
          />
        ) : null}
      </ScrollView>
    </ScreenShell>
  );
}

const styles = StyleSheet.create({
  content: {
    gap: 14,
    paddingBottom: 24,
  },
  hero: {
    alignItems: 'center',
    gap: 10,
    paddingVertical: 24,
  },
  statusIcon: {
    width: 60,
    height: 60,
    borderRadius: 30,
    alignItems: 'center',
    justifyContent: 'center',
  },
  badgeText: {
    textAlign: 'center',
  },
  badge: {
    maxWidth: '100%',
    paddingHorizontal: 12,
    paddingVertical: 4,
    borderRadius: 999,
    borderWidth: 1,
  },
  centre: {
    textAlign: 'center',
  },
  section: {
    gap: 6,
    padding: 16,
  },
  detailRow: {
    flexDirection: 'row',
    justifyContent: 'space-between',
    gap: 16,
    paddingVertical: 6,
  },
  detailValue: {
    flex: 1,
    textAlign: 'right',
  },
});