import 'package:flutter/material.dart';
import 'package:flutter_svg/svg.dart';
import 'package:kmobile/api/services/beneficiary_service.dart';
import 'package:kmobile/data/models/ifsc.dart';
import 'package:kmobile/data/models/beneficiary.dart';
import 'package:kmobile/data/models/user.dart';
import 'beneficiary_result_page.dart';
import 'package:material_symbols_icons/material_symbols_icons.dart';
import '../../../di/injection.dart';
import '../../../l10n/app_localizations.dart';

class AddBeneficiaryScreen extends StatefulWidget {
  final List<User>? users;
  final int? selectedIndex;

  const AddBeneficiaryScreen({
    super.key,
    this.users,
    this.selectedIndex,
  });

  @override
  State<AddBeneficiaryScreen> createState() => _AddBeneficiaryScreen();
}

class _AddBeneficiaryScreen extends State<AddBeneficiaryScreen> {
  final _formKey = GlobalKey<FormState>();

  late User selectedUser = (widget.users ?? [])[widget.selectedIndex!];
  final TextEditingController accountNumberController = TextEditingController();
  final TextEditingController confirmAccountNumberController =
      TextEditingController();
  final TextEditingController nameController = TextEditingController();
  final TextEditingController bankNameController = TextEditingController();
  final TextEditingController branchNameController = TextEditingController();
  final TextEditingController ifscController = TextEditingController();
  final TextEditingController phoneController = TextEditingController();
  
  String? _beneficiaryName;
  bool _isValidating = false;
  bool _isBeneficiaryValidated = false;
  String? _validationError;

  late String accountType;

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addPostFrameCallback((_) {
      setState(() {
        accountType = AppLocalizations.of(context).savings;
      });
    });
  }

  

ifsc? _ifscData;
bool _isLoading = false; //for validateIFSC()

     void _validateIFSC() async {
      var beneficiaryService = getIt<BeneficiaryService>();
      final ifsc = ifscController.text.trim().toUpperCase();
      if (ifsc.isEmpty) return;
      setState(() {
        _isLoading = true;
        _ifscData = null;
      });

    final result = await beneficiaryService.validateIFSC(ifsc);

  setState(() {
    _isLoading = false;
    _ifscData = result;
  });

  if (result == null) {
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(content: Text(AppLocalizations.of(context).invalidIfsc)),
    );
    bankNameController.clear();
     branchNameController.clear();
  } else {
      print("${AppLocalizations.of(context).validIfsc}: ${result.bankName}, ${result.branchName}");
      bankNameController.text = result.bankName;
      branchNameController.text = result.branchName;
  }
 }

 
Future<void> _validateBeneficiary() async {
  // start spinner / disable button
  setState(() {
    _isValidating = true;
    _validationError = null;
    _isBeneficiaryValidated = false;
    nameController.text = ''; // clear previous name
  });

  final String accountNo = accountNumberController.text.trim();
  final String ifsc = ifscController.text.trim();
  final String remitter = selectedUser.name ?? ''; 

  final service = getIt<BeneficiaryService>();
  try {
    // Step 1: call validate API -> get refNo
    final String? refNo = await service.validateBeneficiary(
      accountNo: accountNo,
      ifscCode: ifsc,
      remitterName: remitter,
    );

    if (refNo == null || refNo.isEmpty) {
      setState(() {
        _validationError = 'Validation request failed. Please check details.';
        _isBeneficiaryValidated = false;
      });
      return;
    }

    // Step 2: poll checkValidationStatus for up to 30 seconds
    const int timeoutSeconds = 30;
    const int intervalSeconds = 2;
    int elapsed = 0;
    String? foundName;

    while (elapsed < timeoutSeconds) {
      final String? name = await service.checkValidationStatus(refNo);

      if (name != null && name.trim().isNotEmpty) {
        foundName = name.trim();
        break;
      }

      await Future.delayed(const Duration(seconds: intervalSeconds));
      elapsed += intervalSeconds;
    }

    if (foundName != null) {
      setState(() {
        nameController.text = foundName!;
        _isBeneficiaryValidated = true;
        _validationError = null;
      });
    } else {
      setState(() {
        _validationError = 'Beneficiary not found within timeout.';
        _isBeneficiaryValidated = false;
      });
    }
  } catch (e, st) {
    // handle unexpected errors
    // print or log if you want
    debugPrint('Error validating beneficiary: $e\n$st');
    setState(() {
      _validationError = 'Something went wrong. Please try again.';
      _isBeneficiaryValidated = false;
    });
  } finally {
    if (mounted) {
      setState(() {
        _isValidating = false;
      });
    }
  }
}



 String _selectedAccountType = 'Savings'; // default value

void validateAndAddBeneficiary() async {
  // Show spinner and disable UI
  showDialog(
    context: context,
    barrierDismissible: false, // Prevent dismiss on tap outside
    builder: (BuildContext context) {
      return WillPopScope(
        onWillPop: () async => false, // Disable back button
        child: const Center(
          child: CircularProgressIndicator(),
        ),
      );
    },
  );

  final beneficiary = Beneficiary(
    accountNo: accountNumberController.text.trim(),
    accountType: _selectedAccountType,
    name: nameController.text.trim(),
    ifscCode: ifscController.text.trim(),
  );

  var service = getIt<BeneficiaryService>();

  try {
    await service.sendForValidation(beneficiary);
    bool isFound = await service.checkIfFound(beneficiary.accountNo);

    if (context.mounted) {
      Navigator.pop(context); // Close the spinner
      Navigator.push(
        context,
        MaterialPageRoute(
          builder: (context) => BeneficiaryResultPage(isSuccess: isFound),
        ),
      );
    }
  } catch (e) {
    Navigator.pop(context); // Close the spinner
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(content: Text(AppLocalizations.of(context).somethingWentWrong)),
    );
  }
}


  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        leading: IconButton(
          icon: const Icon(Symbols.arrow_back_ios_new),
          onPressed: () {
            Navigator.pop(context);
          },
        ),
        title: Text(
          AppLocalizations.of(context).addBeneficiary,
          style: TextStyle(color: Colors.black, fontWeight: FontWeight.w500),
        ),
        centerTitle: false,
        actions: [
          Padding(
            padding: const EdgeInsets.only(right: 10.0),
            child: CircleAvatar(
              backgroundColor: Colors.grey[200],
              radius: 20,
              child: SvgPicture.asset(
                'assets/images/avatar_male.svg',
                width: 40,
                height: 40,
                fit: BoxFit.cover,
              ),
            ),
          ),
        ],
      ),
      body: SafeArea(
        child: Form(
          key: _formKey,
          child: Column(
            children: [
              Expanded(
                child: SingleChildScrollView(
                  physics: const AlwaysScrollableScrollPhysics(),
                  child: Padding(
                    padding: const EdgeInsets.all(10.0),
                    child: Column(
                      children: [
                        TextFormField(
                          controller: accountNumberController,
                          decoration: InputDecoration(
                            labelText: AppLocalizations.of(
                              context,
                            ).accountNumber,
                            // prefixIcon: Icon(Icons.person),
                            border: OutlineInputBorder(),
                            isDense: true,
                            filled: true,
                            fillColor: Theme.of(context).scaffoldBackgroundColor,
                            enabledBorder: const OutlineInputBorder(
                              borderSide: BorderSide(color: Colors.black),
                            ),
                            focusedBorder: const OutlineInputBorder(
                              borderSide: BorderSide(
                                color: Colors.black,
                                width: 2,
                              ),
                            ),
                          ),
                          obscureText: true,
                          keyboardType: TextInputType.number,
                          textInputAction: TextInputAction.next,
                          validator: (value) {
                            if (value == null || value.length < 10) {
                              return AppLocalizations.of(
                                context,
                              ).enterValidAccountNumber;
                            }
                            return null;
                          },
                        ),
                        const SizedBox(height: 24),
                        // Confirm Account Number
                        TextFormField(
                          controller: confirmAccountNumberController,
                          decoration: InputDecoration(
                            labelText: AppLocalizations.of(
                              context,
                            ).confirmAccountNumber,
                            // prefixIcon: Icon(Icons.person),
                            border: OutlineInputBorder(),
                            isDense: true,
                            filled: true,
                            fillColor: Theme.of(context).scaffoldBackgroundColor,
                            enabledBorder: const OutlineInputBorder(
                              borderSide: BorderSide(color: Colors.black),
                            ),
                            focusedBorder: const OutlineInputBorder(
                              borderSide: BorderSide(
                                color: Colors.black,
                                width: 2,
                              ),
                            ),
                          ),
                          keyboardType: TextInputType.number,
                          textInputAction: TextInputAction.next,
                          validator: (value) {
                            if (value == null || value.isEmpty) {
                              return AppLocalizations.of(
                                context,
                              ).reenterAccountNumber;
                            }
                            if (value != accountNumberController.text) {
                              return AppLocalizations.of(
                                context,
                              ).accountMismatch;
                            }
                            return null;
                          },
                        ),
                        const SizedBox(height: 24),
                        // 🔹 IFSC Code Field
                        TextFormField(
                          controller: ifscController,
                          decoration: InputDecoration(
                            labelText: AppLocalizations.of(context).ifscCode,
                            border: const OutlineInputBorder(),
                            isDense: true,
                            filled: true,
                            fillColor: Theme.of(context).scaffoldBackgroundColor,
                            enabledBorder: const OutlineInputBorder(
                              borderSide: BorderSide(color: Colors.black),
                            ),
                            focusedBorder: const OutlineInputBorder(
                              borderSide: BorderSide(
                                color: Colors.black,
                                width: 2,
                              ),
                            ),
                          ),
                          textCapitalization: TextCapitalization.characters,
                          textInputAction: TextInputAction.next,
                          onFieldSubmitted: (_) {
                            _validateIFSC();
                          },
                          onChanged: (value) {
                            final trimmed = value.trim().toUpperCase();
                            if (trimmed.length < 11) {
                              // clear bank/branch if backspace or changed
                              bankNameController.clear();
                              branchNameController.clear();
                            }
                          },
                          validator: (value) {
                            final pattern = RegExp(r'^[A-Z]{4}0[A-Z0-9]{6}$');
                            if (value == null || value.trim().isEmpty) {
                              return AppLocalizations.of(context).enterIfsc;
                            } else if (!pattern.hasMatch(
                              value.trim().toUpperCase(),
                            )) {
                              return AppLocalizations.of(
                                context,
                              ).invalidIfscFormat;
                            }
                            return null;
                          },
                        ),

                        const SizedBox(height: 24),
                        // 🔹 Bank Name (Disabled)
                        TextFormField(
                          controller: bankNameController,
                          enabled: false, // changed from readOnly to disabled
                          decoration: InputDecoration(
                            labelText: AppLocalizations.of(context).bankName,
                            border: const OutlineInputBorder(),
                            isDense: true,
                            filled: true,
                            fillColor: Theme.of(context).dialogBackgroundColor, // disabled color
                            enabledBorder: const OutlineInputBorder(
                              borderSide: BorderSide(color: Colors.black),
                            ),
                            focusedBorder: const OutlineInputBorder(
                              borderSide: BorderSide(
                                color: Colors.black,
                                width: 2,
                              ),
                            ),
                          ),
                        ),

                        const SizedBox(height: 24),
                        // 🔹 Branch Name (Disabled)
                        TextFormField(
                          controller: branchNameController,
                          enabled: false, // changed from readOnly to disabled
                          decoration: InputDecoration(
                            labelText: AppLocalizations.of(context).branchName,
                            border: const OutlineInputBorder(),
                            isDense: true,
                            filled: true,
                            fillColor: Theme.of(context).dialogBackgroundColor,
                            enabledBorder: const OutlineInputBorder(
                              borderSide: BorderSide(color: Colors.black),
                            ),
                            focusedBorder: const OutlineInputBorder(
                              borderSide: BorderSide(
                                color: Colors.black,
                                width: 2,
                              ),
                            ),
                          ),
                        ),
//Validate Beneficiary Name
if (!_isBeneficiaryValidated)
  Padding(
    padding: const EdgeInsets.only(top: 12.0),
    child: SizedBox(
      width: double.infinity,
      child: ElevatedButton(
        onPressed: _isValidating
            ? null
            : () {
                if (
                    confirmAccountNumberController.text ==
                        accountNumberController.text) {
                  _validateBeneficiary();
                } else {
                  setState(() {
                    _validationError =
                        'Please enter a valid and matching account number.';
                  });
                }
              },
        child: _isValidating
            ? const SizedBox(
                width: 20,
                height: 20,
                child: CircularProgressIndicator(strokeWidth: 2),
              )
            : const Text('Validate Beneficiary'),
      ),
    ),
  ),
                        //Beneficiary Name (Disabled)
                        TextFormField(
  controller: nameController,
  enabled: false,
  decoration: InputDecoration(
    labelText: AppLocalizations.of(context).beneficiaryName,
    border: const OutlineInputBorder(),
    isDense: true,
    filled: true,
    fillColor: Theme.of(context).dialogBackgroundColor,
    enabledBorder: const OutlineInputBorder(
      borderSide: BorderSide(color: Colors.black),
    ),
    focusedBorder: const OutlineInputBorder(
      borderSide: BorderSide(color: Colors.black, width: 2),
    ),
  ),
  textInputAction: TextInputAction.next,
  validator: (value) => value == null || value.isEmpty
      ? AppLocalizations.of(context).nameRequired
      : null,
),
                        const SizedBox(height: 24),
                        // 🔹 Account Type Dropdown
                        DropdownButtonFormField<String>(
                          value: accountType,
                          decoration: InputDecoration(
                            labelText: AppLocalizations.of(context).accountType,
                            border: const OutlineInputBorder(),
                            isDense: true,
                            filled: true,
                            fillColor: Theme.of(context).scaffoldBackgroundColor,
                            enabledBorder: const OutlineInputBorder(
                              borderSide: BorderSide(color: Colors.black),
                            ),
                            focusedBorder: const OutlineInputBorder(
                              borderSide: BorderSide(
                                color: Colors.black,
                                width: 2,
                              ),
                            ),
                          ),
                          items:
                              [
                                    AppLocalizations.of(context).savings,
                                    AppLocalizations.of(context).current,
                                  ]
                                  .map(
                                    (type) => DropdownMenuItem(
                                      value: type,
                                      child: Text(type),
                                    ),
                                  )
                                  .toList(),
                          onChanged: (value) {
                            setState(() {
                              accountType = value!;
                            });
                          },
                        ),

                        const SizedBox(height: 24),
                        TextFormField(
                          controller: phoneController,
                          keyboardType: TextInputType.phone,
                          decoration: InputDecoration(
                            labelText: AppLocalizations.of(context).phone,
                            prefixIcon: const Icon(Icons.phone),
                            border: const OutlineInputBorder(),
                            isDense: true,
                            filled: true,
                            fillColor: Theme.of(context).scaffoldBackgroundColor,
                            enabledBorder: const OutlineInputBorder(
                              borderSide: BorderSide(color: Colors.black),
                            ),
                            focusedBorder: const OutlineInputBorder(
                              borderSide: BorderSide(
                                color: Colors.black,
                                width: 2,
                              ),
                            ),
                          ),
                          textInputAction: TextInputAction.done,
                          validator: (value) =>
                              value == null || value.length != 10
                              ? AppLocalizations.of(context).enterValidPhone
                              : null,
                        ),
                        const SizedBox(height: 35),
                      ],
                    ),
                  ),
                ),
              ),
              Padding(
                padding: const EdgeInsets.all(16.0),
                child: SizedBox(
                  width: 250,
                  child: ElevatedButton(
                    onPressed:
                    validateAndAddBeneficiary,
                    style: ElevatedButton.styleFrom(
                      shape: const StadiumBorder(),
                      padding: const EdgeInsets.symmetric(vertical: 16),
                      backgroundColor: Theme.of(context).primaryColorDark,
                      foregroundColor: Theme.of(context).scaffoldBackgroundColor,
                    ),
                    child: Text(AppLocalizations.of(context).validateAndAdd),
                  ),
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}