import React from 'react';
import { View, Text, StyleSheet, FlatList } from 'react-native';
import { NativeStackScreenProps } from '@react-navigation/native-stack';
import { Icon } from '../../../components/Icon';
import Animated, { FadeInUp } from 'react-native-reanimated';

import { ScreenShell } from '../../../components';
import { useTheme, fontFamily } from '../../../theme';
import { useAppSelector } from '../../../app/hooks';
import { selectCustomerById } from '../store/agentSelectors';
import type { AgentCustomersStackParamList } from '../navigation/agentNavigationTypes';
import { formatAgentCurrency, formatDateTime } from '../utils/agentFormatters';

import { AgentEmptyState } from '../components/AgentEmptyState';

type Props = NativeStackScreenProps<AgentCustomersStackParamList, 'CustomerInstallmentHistory'>;

export default function CustomerInstallmentHistoryScreen({ route, navigation }: Props) {
  const { customerId } = route.params;
  const theme = useTheme();
  
  const customer = useAppSelector(selectCustomerById(customerId));

  if (!customer) {
    return (
      <ScreenShell title="Installment History">
        <AgentEmptyState title="Error" description="Customer not found" />
      </ScreenShell>
    );
  }

  // Generate mock history based on totalCollected for demo purposes
  const history = Array.from({ length: 10 }).map((_, i) => {
    const isPaid = i < (customer.totalCollected / 500);
    const date = new Date();
    date.setDate(date.getDate() - (i * 30));
    return {
      id: `hist-${i}`,
      amount: 500,
      date: date.toISOString(),
      status: isPaid ? 'paid' : 'pending',
      receiptNo: isPaid ? `RCP-${date.getFullYear()}${String(date.getMonth()+1).padStart(2,'0')}${String(date.getDate()).padStart(2,'0')}-${1000+i}` : null,
    };
  });

  const renderItem = ({ item, index }: { item: any, index: number }) => (
    <Animated.View entering={FadeInUp.delay(index * 50)} style={[styles.card, { backgroundColor: theme.colors.surface, borderColor: theme.colors.cardBorder }]}>
      <View style={styles.leftSide}>
        <View style={[styles.iconFrame, { backgroundColor: item.status === 'paid' ? theme.tint(theme.colors.success, 0.08) : theme.tint(theme.colors.warning, 0.08) }]}>
          <Icon 
            name={item.status === 'paid' ? 'checkmark-circle' : 'time'} 
            size={20} 
            color={item.status === 'paid' ? theme.colors.success : theme.colors.warning} 
          />
        </View>
        <View>
          <Text style={[styles.date, { color: theme.colors.textPrimary }]}>{formatDateTime(item.date)}</Text>
          {item.receiptNo ? (
            <Text style={[styles.receipt, { color: theme.colors.textMuted }]}>{item.receiptNo}</Text>
          ) : (
            <Text style={[styles.receipt, { color: theme.colors.textMuted }]}>Pending Installment</Text>
          )}
        </View>
      </View>
      <View style={styles.rightSide}>
        <Text style={[styles.amount, { color: theme.colors.textPrimary }]}>{formatAgentCurrency(item.amount)}</Text>
        <Text style={[styles.status, { color: item.status === 'paid' ? theme.colors.success : theme.colors.warning }]}>
          {item.status.toUpperCase()}
        </Text>
      </View>
    </Animated.View>
  );

  return (
    <ScreenShell title="Installment History" scrollable={false}>
      <View style={[styles.header, { borderBottomColor: theme.colors.cardBorder }]}>
        <Text style={[styles.customerName, { color: theme.colors.textPrimary }]}>{customer.name}</Text>
        <Text style={[styles.accNumber, { color: theme.colors.textMuted }]}>
          {customer.accounts[0]?.type} A/C: {customer.accounts[0]?.accountNumber}
        </Text>
      </View>
      
      <FlatList
        data={history}
        keyExtractor={item => item.id}
        renderItem={renderItem}
        contentContainerStyle={styles.listContent}
        showsVerticalScrollIndicator={false}
      />
    </ScreenShell>
  );
}

const styles = StyleSheet.create({
  header: {
    padding: 16,
    paddingTop: 8,
    borderBottomWidth: 1,
  },
  customerName: {
    fontSize: 18,
    fontFamily: fontFamily.bold,
    marginBottom: 4,
  },
  accNumber: {
    fontSize: 14,
    fontFamily: fontFamily.mono,
  },
  listContent: {
    padding: 16,
  },
  card: {
    flexDirection: 'row',
    justifyContent: 'space-between',
    alignItems: 'center',
    padding: 16,
    borderRadius: 16,
    borderWidth: 1,
    marginBottom: 12,
  },
  leftSide: {
    flexDirection: 'row',
    alignItems: 'center',
    gap: 12,
  },
  iconFrame: {
    width: 40,
    height: 40,
    borderRadius: 20,
    alignItems: 'center',
    justifyContent: 'center',
  },
  date: {
    fontSize: 14,
    fontFamily: fontFamily.semibold,
    marginBottom: 2,
  },
  receipt: {
    fontSize: 11,
  },
  rightSide: {
    alignItems: 'flex-end',
  },
  amount: {
    fontSize: 15,
    fontFamily: fontFamily.bold,
    marginBottom: 2,
  },
  status: {
    fontSize: 10,
    fontFamily: fontFamily.bold,
  },
});