import React, { useState, useEffect, useLayoutEffect } from "react";
import {
  View,
  Text,
  StyleSheet,
  TouchableOpacity,
  ActivityIndicator,
} from "react-native";
import { useNavigation, useRoute } from "@react-navigation/native";
import { useRouter } from "expo-router";
import api from "@/services/axiosClient";
import { BASE_URL } from "@/constants/config";
import { useSnackbar } from "@/contexts/Snackbar";
import { SafeAreaView } from "react-native-safe-area-context";

// Import your success/failure icons
import SuccessIcon from "@/assets/icons/check_circle.svg";
import FailureIcon from "@/assets/icons/cancel.svg";
import PendingIcon from "@/assets/icons/pending.svg";

interface TransactionDetailData {
  id: number;
  amount: string;
  status: string;
  transaction_date: string | null;
  upi_handle: string;
  payment_mode: string[];
  paid_by_upi_handle: string | null;
  order_id: string;
  payment_reference_id: string | null;
  transaction_order_id: string;
}

interface TransactionResponse {
  success: boolean;
  data: {
    payments: TransactionDetailData[];
    pagination: {
      total_records: number;
      page_number: number;
      page_size: number;
    };
  };
}

export default function TransactionDetailScreen() {
  const navigation = useNavigation();
  const route = useRoute();
  const router = useRouter();
  const { showSnackbar } = useSnackbar();

  // Get payment ID from route params
  const { paymentId } = route.params as { paymentId: number };

  const [transactionData, setTransactionData] =
    useState<TransactionDetailData | null>(null);
  const [isLoading, setIsLoading] = useState(true);

  useLayoutEffect(() => {
    navigation.setOptions({
      headerStyle: {
        backgroundColor: "#F3F5F8",
      },
      headerTitle: "Transaction Detail",
      headerTitleStyle: {
        fontSize: 18,
        fontWeight: "600",
        color: "#111827",
      },
      headerLeft: () => (
        <TouchableOpacity
          onPress={() => router.back()}
          style={styles.backButton}
        >
          <Text style={styles.backText}>‹</Text>
        </TouchableOpacity>
      ),
    });
  }, [navigation, router]);

  useEffect(() => {
    fetchTransactionDetail();
  }, [paymentId]);

  const fetchTransactionDetail = async () => {
    try {
      setIsLoading(true);
      const response = await api.get(
        `${BASE_URL}/api/v1/payment-history?id=${paymentId}`
      );
      const result: TransactionResponse = response.data;

      if (result.success && result.data.payments.length > 0) {
        setTransactionData(result.data.payments[0]);
      } else {
        showSnackbar("Transaction details not found", "error");
        router.back();
      }
    } catch (err) {
      console.error("Error fetching transaction details:", err);
      const errorMessage =
        err instanceof Error ? err.message : "Something went wrong";
      showSnackbar(errorMessage, "error");
      router.back();
    } finally {
      setIsLoading(false);
    }
  };

  const formatCurrency = (amount: string) => {
    return `₹${parseFloat(amount).toLocaleString()}`;
  };

  const formatDateTime = (dateString: string | null) => {
    if (!dateString) return "--";
    const date = new Date(dateString);
    const dateStr = date.toLocaleDateString("en-IN", {
      day: "2-digit",
      month: "long",
      year: "numeric",
    });
    const timeStr = date.toLocaleTimeString("en-US", {
      hour: "numeric",
      minute: "2-digit",
      hour12: true,
    });
    const dayStr = date.toLocaleDateString("en-US", { weekday: "long" });
    return `${dateStr}, ${timeStr}, ${dayStr}`;
  };

  const getStatusIcon = (status: string) => {
    if (status.toLowerCase() === "confirmed") {
      return <SuccessIcon width={80} height={80} />;
    } else if (status.toLowerCase() === "pending") {
      return <PendingIcon width={80} height={80} />;
    } else {
      return <FailureIcon width={80} height={80} />;
    }
  };

  const getStatusText = (status: string) => {
    switch (status.toLowerCase()) {
      case "success":
      case "completed":
      case "confirmed":
        return "Payment successful";
      case "failure":
      case "failed":
        return "Payment failed";
      case "pending":
        return "Payment pending";
      default:
        return `Payment ${status}`;
    }
  };

  if (isLoading) {
    return (
      <SafeAreaView style={styles.container}>
        <View style={styles.loadingContainer}>
          <ActivityIndicator size="large" color="#00BE88" />
        </View>
      </SafeAreaView>
    );
  }

  if (!transactionData) {
    return (
      <SafeAreaView style={styles.container}>
        <View style={styles.errorContainer}>
          <Text style={styles.errorText}>Transaction not found</Text>
        </View>
      </SafeAreaView>
    );
  }

  return (
    <SafeAreaView style={styles.container}>
      <View style={styles.content}>
        {/* Status Icon */}
        <View style={styles.iconContainer}>
          {getStatusIcon(transactionData.status)}
        </View>

        {/* Amount */}
        <Text style={styles.amount}>
          {formatCurrency(transactionData.amount)}
        </Text>

        {/* Status Text */}
        <Text style={styles.statusText}>
          {getStatusText(transactionData.status)}
        </Text>

        {/* Date Time */}
        <Text style={styles.dateTime}>
          {formatDateTime(transactionData.transaction_date)}
        </Text>

        {/* Transaction Details Card */}
        <View style={styles.detailsCard}>
          <Text style={styles.detailsTitle}>Transaction Details</Text>

          <DetailRow
            label="Payment mode"
            value={transactionData.payment_mode.join(", ") || "--"}
          />

          <DetailRow
            label="Paid to"
            value={transactionData.upi_handle || "--"}
          />

          <DetailRow
            label="Paid by"
            value={transactionData.paid_by_upi_handle || "--"}
          />

          <DetailRow
            label="Order ID"
            value={transactionData.order_id || "--"}
          />

          <DetailRow
            label="Transaction ID"
            value={transactionData.transaction_order_id || "--"}
          />

          <DetailRow
            label="RRN"
            value={transactionData.payment_reference_id || "--"}
            isLast={true}
          />
        </View>
      </View>
    </SafeAreaView>
  );
}

const DetailRow = ({
  label,
  value,
  isLast = false,
}: {
  label: string;
  value: string;
  isLast?: boolean;
}) => (
  <View style={[styles.detailRow, isLast && styles.detailRowLast]}>
    <Text style={styles.detailLabel}>{label}</Text>
    <Text style={styles.detailValue}>{value}</Text>
  </View>
);

const styles = StyleSheet.create({
  container: {
    flex: 1,
    backgroundColor: "#F3F5F8",
  },
  loadingContainer: {
    flex: 1,
    justifyContent: "center",
    alignItems: "center",
  },
  errorContainer: {
    flex: 1,
    justifyContent: "center",
    alignItems: "center",
  },
  errorText: {
    fontSize: 16,
    color: "#6B7280",
  },
  content: {
    flex: 1,
    padding: 16,
    alignItems: "center",
  },
  backButton: {
    paddingLeft: 16,
    paddingRight: 8,
    paddingVertical: 8,
  },
  backText: {
    fontSize: 24,
    color: "#111827",
    fontWeight: "300",
  },
  iconContainer: {
    marginTop: 32,
    marginBottom: 16,
  },
  successIcon: {
    width: 60,
    height: 60,
    borderRadius: 30,
    backgroundColor: "#00BE88",
    justifyContent: "center",
    alignItems: "center",
  },
  failureIcon: {
    width: 60,
    height: 60,
    borderRadius: 30,
    backgroundColor: "#EF4444",
    justifyContent: "center",
    alignItems: "center",
  },
  checkmark: {
    color: "white",
    fontSize: 24,
    fontWeight: "bold",
  },
  xmark: {
    color: "white",
    fontSize: 20,
    fontWeight: "bold",
  },
  amount: {
    fontSize: 20,
    fontWeight: "600",
    color: "#252A34",
    marginBottom: 16,
  },
  statusText: {
    fontSize: 14,
    fontWeight: "400",
    color: "#252A34",
    marginBottom: 4,
  },
  dateTime: {
    fontSize: 14,
    color: "#252A34",
    textAlign: "center",
    marginBottom: 24,
  },
  detailsCard: {
    backgroundColor: "#FCFCFC",
    borderRadius: 8,
    padding: 16,
    width: "100%",
  },
  detailsTitle: {
    fontSize: 14,
    fontWeight: "600",
    color: "#252A34",
    marginBottom: 8,
  },
  detailRow: {
    flexDirection: "row",
    justifyContent: "space-between",
    alignItems: "flex-start",
    paddingVertical: 8,
    borderBottomWidth: 1,
    borderBottomColor: "#E5E9F0",
  },
  detailRowLast: {
    borderBottomWidth: 0,
  },
  detailLabel: {
    fontSize: 14,
    color: "#252A34",
    flex: 1,
  },
  detailValue: {
    fontSize: 14,
    fontWeight: "600",
    color: "#252A34",
    flex: 1,
    textAlign: "right",
  },
});