import 'dart:async';
import 'dart:convert';

import 'package:dio/dio.dart';
import 'package:flutter/material.dart';
import 'package:kmobile/api/services/neft_service.dart';
import 'package:kmobile/api/services/rtgs_service.dart';
import 'package:kmobile/data/models/beneficiary.dart';
import 'package:kmobile/data/models/neft_transaction.dart';
import 'package:kmobile/data/models/payment_response.dart';
import 'package:kmobile/data/models/rtgs_transaction.dart';
import 'package:kmobile/di/injection.dart';
import 'package:kmobile/features/fund_transfer/screens/payment_animation.dart';
import 'package:kmobile/features/fund_transfer/screens/transaction_pin_screen.dart';
import '../../../l10n/app_localizations.dart';

enum TransactionMode { neft, rtgs }

class FundTransferAmountScreen extends StatefulWidget {
  final String debitAccountNo;
  final Beneficiary creditBeneficiary;
  final String remitterName;

  const FundTransferAmountScreen({
    super.key,
    required this.debitAccountNo,
    required this.creditBeneficiary,
    required this.remitterName,
  });

  @override
  State<FundTransferAmountScreen> createState() =>
      _FundTransferAmountScreenState();
}

class _FundTransferAmountScreenState extends State<FundTransferAmountScreen> {
  final _amountController = TextEditingController();
  final _formKey = GlobalKey<FormState>();
  TransactionMode _selectedMode = TransactionMode.neft;

  @override
  void dispose() {
    _amountController.dispose();
    super.dispose();
  }

  Widget _getBankLogo(String? bankName) {
    if (bankName != null && bankName.toLowerCase().contains('state bank of india')) {
      return Image.asset(
        'assets/images/sbi_logo.png',
        width: 40,
        height: 40,
      );
    } else {
      return const Icon(
        Icons.account_balance,
        size: 40,
        color: Colors.grey,
      );
    }
  }

  void _onProceed() {
    if (_formKey.currentState!.validate()) {
      final amount = double.tryParse(_amountController.text) ?? 0;

      if (_selectedMode == TransactionMode.rtgs && amount < 200000) {
        showDialog(
          context: context,
          builder: (ctx) => AlertDialog(
            title: const Text('Invalid Amount for RTGS'),
            content: const Text(
                'RTGS transactions require a minimum amount of 200,000. Please enter a higher amount or select NEFT as the transaction mode.'),
            actions: [
              TextButton(
                onPressed: () => Navigator.of(ctx).pop(),
                child: const Text('OK'),
              ),
            ],
          ),
        );
        return; // Stop further execution
      }

      Navigator.push(
        context,
        MaterialPageRoute(
          builder: (context) => TransactionPinScreen(
            onPinCompleted: (pinScreenContext, tpin) async {
              if (_selectedMode == TransactionMode.neft) {
                final neftTx = NeftTransaction(
                  fromAccount: widget.debitAccountNo,
                  toAccount: widget.creditBeneficiary.accountNo,
                  amount: _amountController.text,
                  ifscCode: widget.creditBeneficiary.ifscCode,
                  remitterName: widget.remitterName,
                  beneficiaryName: widget.creditBeneficiary.name,
                  tpin: tpin,
                );
                final neftService = getIt<NeftService>();

                final completer = Completer<PaymentResponse>();

                Navigator.of(pinScreenContext).pushReplacement(
                  MaterialPageRoute(
                    builder: (_) => PaymentAnimationScreen(
                        paymentResponse: completer.future),
                  ),
                );

                try {
                  final neftResponse =
                      await neftService.processNeftTransaction(neftTx);
                  final paymentResponse = PaymentResponse(
                    isSuccess: neftResponse.message.toUpperCase() == 'SUCCESS',
                    date: DateTime.now(),
                    creditedAccount: neftTx.toAccount,
                    amount: neftTx.amount,
                    currency: 'INR',
                    utr: neftResponse.utr,
                  );
                  completer.complete(paymentResponse);
                } on DioException catch(e) {
                  print('dio exception');
                  print(e.toString());
                
                  final error = jsonDecode(e.response.toString())['error'];
                  var errorMessage = 
                  {
                    "INCORRECT_TPIN" : "Please Enter the correct TPIN",
                    "INSUFFICIENT_FUNDS": "Your account does not have sufficient balance"
                  }[error] ?? "Something Went Wrong";
                
                    final paymentResponse = PaymentResponse(
                    isSuccess: false,
                    errorMessage: errorMessage,
                  );
                  completer.complete(paymentResponse);
                } catch (e) {
                  print('generic exception');
                  print(e.toString());
                  final paymentResponse = PaymentResponse(
                    isSuccess: false,
                    errorMessage: "Something went Wrong",
                  );
                  completer.complete(paymentResponse);
                }
              } else {
                final rtgsTx = RtgsTransaction(
                  fromAccount: widget.debitAccountNo,
                  toAccount: widget.creditBeneficiary.accountNo,
                  amount: _amountController.text,
                  ifscCode: widget.creditBeneficiary.ifscCode,
                  remitterName: widget.remitterName,
                  beneficiaryName: widget.creditBeneficiary.name,
                  tpin: tpin,
                );
                final rtgsService = getIt<RtgsService>();
                final completer = Completer<PaymentResponse>();

                Navigator.of(pinScreenContext).pushReplacement(
                  MaterialPageRoute(
                    builder: (_) => PaymentAnimationScreen(
                        paymentResponse: completer.future),
                  ),
                );

                try {
                  final rtgsResponse =
                      await rtgsService.processRtgsTransaction(rtgsTx);
                  final paymentResponse = PaymentResponse(
                    isSuccess: rtgsResponse.message.toUpperCase() == 'SUCCESS',
                    date: DateTime.now(),
                    creditedAccount: rtgsTx.toAccount,
                    amount: rtgsTx.amount,
                    currency: 'INR',
                    utr: rtgsResponse.utr,
                  );
                  completer.complete(paymentResponse);
                } on DioException catch(e) {
                  print('dio exception');
                  print(e.toString());
                
                  final error = jsonDecode(e.response.toString())['error'];
                  var errorMessage = 
                  {
                    "INCORRECT_TPIN" : "Please Enter the correct TPIN",
                    "INSUFFICIENT_FUNDS": "Your account does not have sufficient balance"
                  }[error] ?? "Something Went Wrong";
                
                    final paymentResponse = PaymentResponse(
                    isSuccess: false,
                    errorMessage: errorMessage,
                  );
                  completer.complete(paymentResponse);
                } catch (e) {
                  print('generic exception');
                  print(e.toString());
                  final paymentResponse = PaymentResponse(
                    isSuccess: false,
                    errorMessage: "Something went Wrong",
                  );
                  completer.complete(paymentResponse);
                }
              }
            },
          ),
        ),
      );
    }
  }

  @override
  Widget build(BuildContext context) {
    final loc = AppLocalizations.of(context);
    return Scaffold(
      appBar: AppBar(
        title: Text(loc.fundTransfer),
      ),
      body: Padding(
        padding: const EdgeInsets.all(16.0),
        child: Form(
          key: _formKey,
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              // Debit Account (User)
              Text(
                loc.debitFrom,
                style: Theme.of(context).textTheme.titleSmall,
              ),
              Card(
                elevation: 0,
                margin: const EdgeInsets.symmetric(vertical: 8.0),
                child: ListTile(
                  leading: Image.asset(
                    'assets/images/logo.png',
                    width: 40,
                    height: 40,
                  ),
                  title: Text(widget.remitterName),
                  subtitle: Text(widget.debitAccountNo),
                ),
              ),
              const SizedBox(height: 24),

              // Credit Account (Beneficiary)
              Text(
                "Credit To",
                style: Theme.of(context).textTheme.titleSmall,
              ),
              Card(
                elevation: 0,
                margin: const EdgeInsets.symmetric(vertical: 8.0),
                child: ListTile(
                  leading: _getBankLogo(widget.creditBeneficiary.bankName),
                  title: Text(widget.creditBeneficiary.name),
                  subtitle: Text(widget.creditBeneficiary.accountNo),
                ),
              ),
              const SizedBox(height: 24),

              // Transaction Mode Selection
              Text(
                "Select Transaction Mode",
                style: Theme.of(context).textTheme.titleMedium,
              ),
              const SizedBox(height: 12),
              Container(
                decoration: BoxDecoration(
                  color: Theme.of(context).cardColor,
                  borderRadius: BorderRadius.circular(12),
                  border: Border.all(color: Colors.grey.shade300),
                ),
                child: ToggleButtons(
                  isSelected: [
                    _selectedMode == TransactionMode.neft,
                    _selectedMode == TransactionMode.rtgs
                  ],
                  onPressed: (index) {
                    setState(() {
                      _selectedMode = TransactionMode.values[index];
                    });
                  },
                  borderRadius: BorderRadius.circular(10),
                  selectedColor: Theme.of(context).colorScheme.onPrimary,
                  fillColor: Theme.of(context).primaryColor,
                  color: Theme.of(context).colorScheme.onSurface,
                  borderColor: Colors.transparent,
                  selectedBorderColor: Colors.transparent,
                  splashColor: Theme.of(context).primaryColor.withOpacity(0.1),
                  highlightColor: Theme.of(context).primaryColor.withOpacity(0.05),
                  children: const [
                    Padding(
                      padding: EdgeInsets.symmetric(horizontal: 24.0, vertical: 12.0),
                      child: Text('NEFT'),
                    ),
                    Padding(
                      padding: EdgeInsets.symmetric(horizontal: 24.0, vertical: 12.0),
                      child: Text('RTGS'),
                    ),
                  ],
                ),
              ),
              const SizedBox(height: 24),

              // Amount
              TextFormField(
                controller: _amountController,
                keyboardType: TextInputType.number,
                decoration: InputDecoration(
                  labelText: loc.amount,
                  border: const OutlineInputBorder(),
                  prefixIcon: const Icon(Icons.currency_rupee),
                ),
                validator: (value) {
                  if (value == null || value.isEmpty) {
                    return loc.amountRequired;
                  }
                  if (double.tryParse(value) == null ||
                      double.parse(value) <= 0) {
                    return loc.validAmount;
                  }
                  return null;
                },
              ),
              const Spacer(),

              // Proceed Button
              SizedBox(
                width: double.infinity,
                child: ElevatedButton(
                  onPressed: _onProceed,
                  style: ElevatedButton.styleFrom(
                    padding: const EdgeInsets.symmetric(vertical: 16),
                  ),
                  child: const Text("Proceed"),
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}