import 'package:flutter_gen/gen_l10n/app_localizations.dart';

import 'package:flutter/material.dart';
import 'package:kmobile/api/services/auth_service.dart';
import 'package:kmobile/di/injection.dart';

enum TPinMode { set, confirm }

class TpinSetScreen extends StatefulWidget {
  const TpinSetScreen({super.key});

  @override
  State<TpinSetScreen> createState() => _TpinSetScreenState();
}

class _TpinSetScreenState extends State<TpinSetScreen> {
  TPinMode _mode = TPinMode.set;
  final List<String> _tpin = [];
  String? _initialTpin;
  String? _errorText;

  void addDigit(String digit) {
    if (_tpin.length < 6) {
      setState(() {
        _tpin.add(digit);
        _errorText = null;
      });
      if (_tpin.length == 6) {
        _handleComplete();
      }
    }
  }

  void deleteDigit() {
    if (_tpin.isNotEmpty) {
      setState(() {
        _tpin.removeLast();
        _errorText = null;
      });
    }
  }

  void _handleComplete() async {
    final pin = _tpin.join();
    if (_mode == TPinMode.set) {
      setState(() {
        _initialTpin = pin;
        _tpin.clear();
        _mode = TPinMode.confirm;
      });
    } else if (_mode == TPinMode.confirm) {
      if (_initialTpin == pin) {
        final authService = getIt<AuthService>();
        try {
          await authService.setTpin(pin);
        } catch (e) {
          setState(() {
            _errorText = "${AppLocalizations.of(context).tpinFailed}";
            _tpin.clear();
          });
          return;
        }
        if (!mounted) return;
        // Show success dialog before popping
        await showDialog(
          context: context,
          barrierDismissible: false,
          builder: (ctx) => AlertDialog(
            shape:
                RoundedRectangleBorder(borderRadius: BorderRadius.circular(18)),
            title: Column(
              children: [
                Icon(Icons.check_circle, color: Colors.green, size: 60),
                SizedBox(height: 12),
                Text(AppLocalizations.of(context).success,
                    style: TextStyle(fontWeight: FontWeight.bold)),
              ],
            ),
            content: Text(
              AppLocalizations.of(context).tpinSetSuccess,
              textAlign: TextAlign.center,
            ),
            actions: [
              TextButton(
                onPressed: () {
                  Navigator.of(ctx).pop();
                },
                child: Text(AppLocalizations.of(context).ok,
                    style: TextStyle(fontSize: 16)),
              ),
            ],
          ),
        );
        if (mounted) {
          Navigator.of(context).pop();
        }
      } else {
        setState(() {
          _errorText = AppLocalizations.of(context).pinsMismatchRetry;
          _tpin.clear();
        });
      }
    }
  }

  Widget buildPinDots() {
    return Row(
      mainAxisAlignment: MainAxisAlignment.center,
      children: List.generate(6, (index) {
        return Container(
          margin: const EdgeInsets.all(8),
          width: 15,
          height: 15,
          decoration: BoxDecoration(
            shape: BoxShape.circle,
            color: index < _tpin.length ? Colors.black : Colors.grey[400],
          ),
        );
      }),
    );
  }

  Widget buildNumberPad() {
    List<List<String>> keys = [
      ['1', '2', '3'],
      ['4', '5', '6'],
      ['7', '8', '9'],
      ['Enter', '0', '<']
    ];

    return Column(
      children: keys.map((row) {
        return Row(
          mainAxisAlignment: MainAxisAlignment.spaceEvenly,
          children: row.map((key) {
            return Padding(
              padding: const EdgeInsets.all(8.0),
              child: GestureDetector(
                onTap: () {
                  if (key == '<') {
                    deleteDigit();
                  } else if (key == 'Enter') {
                    if (_tpin.length == 6) {
                      _handleComplete();
                    } else {
                      setState(() {
                        _errorText =
                            AppLocalizations.of(context).pleaseEnter6Digits;
                      });
                    }
                  } else if (key.isNotEmpty) {
                    addDigit(key);
                  }
                },
                child: Container(
                  width: 70,
                  height: 70,
                  decoration: BoxDecoration(
                    shape: BoxShape.circle,
                    color: Colors.grey[200],
                  ),
                  alignment: Alignment.center,
                  child: key == 'Enter'
                      ? const Icon(Icons.check)
                      : Text(
                          key == '<' ? '⌫' : key,
                          style: TextStyle(
                            fontSize: 20,
                            color: key == 'Enter' ? Colors.blue : Colors.black,
                          ),
                        ),
                ),
              ),
            );
          }).toList(),
        );
      }).toList(),
    );
  }

  String getTitle() {
    switch (_mode) {
      case TPinMode.set:
        return AppLocalizations.of(context).setNewTpin;
      case TPinMode.confirm:
        return AppLocalizations.of(context).confirmNewTpin;
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text(AppLocalizations.of(context).setTpin)),
      body: SafeArea(
        child: Column(
          children: [
            const Spacer(),
            const Icon(Icons.lock_outline, size: 60, color: Colors.blue),
            const SizedBox(height: 20),
            Text(
              getTitle(),
              style: const TextStyle(fontSize: 20, fontWeight: FontWeight.w500),
            ),
            const SizedBox(height: 20),
            buildPinDots(),
            if (_errorText != null)
              Padding(
                padding: const EdgeInsets.only(top: 8.0),
                child: Text(_errorText!,
                    style: const TextStyle(color: Colors.red)),
              ),
            const Spacer(),
            buildNumberPad(),
            const Spacer(),
          ],
        ),
      ),
    );
  }
}