/// Email/password sign-in against PocketBase.
library;

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:pocketbase/pocketbase.dart';
import 'package:provider/provider.dart';

import '../providers/auth_provider.dart';
import '../utils/constants.dart';
import '../widgets/app_text_field.dart';
import '../widgets/responsive_body.dart';

class LoginScreen extends StatefulWidget {
  const LoginScreen({super.key, this.asRoot = false});

  /// When true (cold start / auth gate), stay put on success so [AuthGate]
  /// rebuilds into the shell. When false, pop with `true` for modal sign-in.
  final bool asRoot;

  @override
  State<LoginScreen> createState() => _LoginScreenState();
}

class _LoginScreenState extends State<LoginScreen> {
  final _formKey = GlobalKey<FormState>();
  final _emailController = TextEditingController();
  final _passwordController = TextEditingController();
  bool _busy = false;
  bool _obscurePassword = true;

  @override
  void dispose() {
    _emailController.dispose();
    _passwordController.dispose();
    super.dispose();
  }

  Future<void> _submit() async {
    if (_busy) return;
    if (!(_formKey.currentState?.validate() ?? false)) return;

    setState(() => _busy = true);
    final auth = context.read<AuthController>();
    try {
      await auth.login(
        email: _emailController.text,
        password: _passwordController.text,
      );
      // Lets iOS/Android password managers offer to save / confirm the login.
      TextInput.finishAutofillContext();
      if (!mounted) return;
      if (!widget.asRoot) {
        Navigator.of(context).pop(true);
      }
    } on ClientException catch (error) {
      if (!mounted) return;
      final message = error.response['message'] as String? ??
          'Sign-in failed. Check email and password.';
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text(message)),
      );
    } catch (error) {
      if (!mounted) return;
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text('Could not reach $kPocketBaseUrl')),
      );
    } finally {
      if (mounted) setState(() => _busy = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);

    return Scaffold(
      appBar: AppBar(
        title: const Text('Sign in'),
        automaticallyImplyLeading: !widget.asRoot,
      ),
      body: ResponsiveBody(
        child: ListView(
          padding: const EdgeInsets.fromLTRB(16, 24, 16, 32),
          children: [
            Text(
              widget.asRoot ? 'Welcome to $kAppName' : 'Sync account',
              style: theme.textTheme.headlineSmall,
            ),
            const SizedBox(height: 8),
            Text(
              widget.asRoot
                  ? 'Sign in to sync labels, notes, and transactions across '
                      'your devices. You can connect your bank afterward.'
                  : 'Sign in to link this device with PocketBase. Labels, notes, '
                      'and bank transactions sync across your devices.',
              style: theme.textTheme.bodyMedium?.copyWith(
                color: theme.colorScheme.onSurfaceVariant,
              ),
            ),
            const SizedBox(height: 24),
            AutofillGroup(
              child: Form(
                key: _formKey,
                child: Column(
                  children: [
                    AppTextField(
                      controller: _emailController,
                      label: 'Email',
                      keyboardType: TextInputType.emailAddress,
                      textInputAction: TextInputAction.next,
                      autofocus: true,
                      autofillHints: const [
                        AutofillHints.email,
                        AutofillHints.username,
                      ],
                      validator: (value) {
                        final text = value?.trim() ?? '';
                        if (text.isEmpty) return 'Enter your email';
                        if (!text.contains('@')) return 'Enter a valid email';
                        return null;
                      },
                    ),
                    const SizedBox(height: 16),
                    TextFormField(
                      controller: _passwordController,
                      obscureText: _obscurePassword,
                      textInputAction: TextInputAction.done,
                      autofillHints: const [AutofillHints.password],
                      enableSuggestions: false,
                      autocorrect: false,
                      onFieldSubmitted: (_) => _submit(),
                      validator: (value) {
                        if (value == null || value.isEmpty) {
                          return 'Enter your password';
                        }
                        return null;
                      },
                      decoration: InputDecoration(
                        labelText: 'Password',
                        suffixIcon: IconButton(
                          tooltip: _obscurePassword
                              ? 'Show password'
                              : 'Hide password',
                          onPressed: () => setState(
                            () => _obscurePassword = !_obscurePassword,
                          ),
                          icon: Icon(
                            _obscurePassword
                                ? Icons.visibility_outlined
                                : Icons.visibility_off_outlined,
                          ),
                        ),
                      ),
                    ),
                    const SizedBox(height: 24),
                    FilledButton.icon(
                      onPressed: _busy ? null : _submit,
                      icon: _busy
                          ? SizedBox(
                              width: 18,
                              height: 18,
                              child: CircularProgressIndicator(
                                strokeWidth: 2,
                                color: theme.colorScheme.onPrimary,
                              ),
                            )
                          : const Icon(Icons.login),
                      label: Text(_busy ? 'Signing in…' : 'Sign in'),
                    ),
                  ],
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }
}