import 'package:flutter/material.dart';
import 'package:notas/theme/app_palette.dart';

class BiometricGateScreen extends StatefulWidget {
  const BiometricGateScreen({
    super.key,
    required this.isBusy,
    required this.onUnlockRequested,
  });

  final bool isBusy;
  final Future<void> Function() onUnlockRequested;

  @override
  State<BiometricGateScreen> createState() => _BiometricGateScreenState();
}

class _BiometricGateScreenState extends State<BiometricGateScreen> {
  bool _autoRequested = false;

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addPostFrameCallback((_) {
      if (mounted) {
        _requestUnlockOnce();
      }
    });
  }

  Future<void> _requestUnlockOnce() async {
    if (_autoRequested || widget.isBusy) {
      return;
    }

    _autoRequested = true;
    await widget.onUnlockRequested();
  }

  @override
  Widget build(BuildContext context) {
    final AppPalette palette = Theme.of(context).extension<AppPalette>()!;

    return Scaffold(
      body: Container(
        decoration: BoxDecoration(gradient: palette.backdropGradient),
        child: SafeArea(
          child: Column(
            children: [
              Expanded(
                child: Center(
                  child: SingleChildScrollView(
                    padding: const EdgeInsets.all(24),
                    child: ConstrainedBox(
                      constraints: const BoxConstraints(maxWidth: 460),
                      child: Container(
                        padding: const EdgeInsets.all(24),
                        decoration: BoxDecoration(
                          color: palette.cardBackground,
                          borderRadius: BorderRadius.circular(24),
                          border: Border.all(color: palette.border),
                          boxShadow: [
                            BoxShadow(
                              color: palette.shadowSoft,
                              blurRadius: 30,
                              offset: const Offset(0, 18),
                            ),
                          ],
                        ),
                        child: Column(
                          mainAxisSize: MainAxisSize.min,
                          crossAxisAlignment: CrossAxisAlignment.stretch,
                          children: [
                            Icon(
                              Icons.fingerprint,
                              size: 44,
                              color: IconTheme.of(context).color,
                            ),
                            const SizedBox(height: 16),
                            const Text(
                              'Desbloqueo biométrico',
                              textAlign: TextAlign.center,
                              style: TextStyle(
                                color: Colors.white,
                                fontSize: 28,
                                fontWeight: FontWeight.w700,
                              ),
                            ),
                            const SizedBox(height: 10),
                            Text(
                              'Pon tu huella o cara para entrar a tus notas.',
                              textAlign: TextAlign.center,
                              style: TextStyle(
                                color: palette.textSecondary,
                                height: 1.4,
                              ),
                            ),
                            const SizedBox(height: 22),
                            FilledButton(
                              onPressed: widget.isBusy
                                  ? null
                                  : widget.onUnlockRequested,
                              style: FilledButton.styleFrom(
                                padding: const EdgeInsets.symmetric(
                                  vertical: 14,
                                ),
                              ),
                              child: widget.isBusy
                                  ? const SizedBox(
                                      width: 18,
                                      height: 18,
                                      child: CircularProgressIndicator(
                                        strokeWidth: 2,
                                      ),
                                    )
                                  : const Text('Desbloquear'),
                            ),
                          ],
                        ),
                      ),
                    ),
                  ),
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}