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

import '../../core/data/remote/api_client.dart';
import '../../core/data/services/auth_controller.dart';
import '../../core/theme/app_colors.dart';
import '../../core/theme/app_theme.dart';
import '../../l10n/app_localizations.dart';
import 'auth_logic.dart';

/// 登录 / 注册页：邮箱 + 密码。
///
/// 风格沿用 FruitShorts 现有页面（深色卡片 + 圆角 + 主色蓝），不另起一套视觉。
class AuthPage extends StatefulWidget {
  const AuthPage({super.key, this.signUpMode = false});

  final bool signUpMode;

  @override
  State<AuthPage> createState() => _AuthPageState();
}

class _AuthPageState extends State<AuthPage> {
  late AuthLogic _logic;

  @override
  void initState() {
    super.initState();
    _logic = AuthLogic(signUpMode: widget.signUpMode);
  }

  String _errorText(AppLocalizations l10n, AuthFieldError error) {
    switch (error) {
      case AuthFieldError.emailRequired:
        return l10n.authEmailRequired;
      case AuthFieldError.emailInvalid:
        return l10n.authEmailInvalid;
      case AuthFieldError.passwordRequired:
        return l10n.authPasswordRequired;
      case AuthFieldError.passwordLength:
        return l10n.authPasswordLength;
      case AuthFieldError.passwordWeak:
        return l10n.authPasswordWeak;
    }
  }

  Future<void> _submit() async {
    final l10n = AppLocalizations.of(context)!;
    final invalid = _logic.validate();
    if (invalid != null) {
      setState(() => _logic.errorMessage = _errorText(l10n, invalid));
      return;
    }
    setState(() {
      _logic.busy = true;
      _logic.errorMessage = null;
    });
    final auth = context.read<AuthController>();
    try {
      if (_logic.signUpMode) {
        await auth.register(
          email: _logic.normalizedEmail,
          password: _logic.password,
        );
      } else {
        await auth.signIn(
          email: _logic.normalizedEmail,
          password: _logic.password,
        );
      }
      if (!mounted) return;
      Navigator.of(context).maybePop();
    } on ApiException catch (error) {
      // 后端文案已经是可直接展示的中文/印尼语提示，错误码不外露
      setState(() => _logic.errorMessage = error.message);
    } catch (_) {
      setState(() => _logic.errorMessage = l10n.authNetworkError);
    } finally {
      if (mounted) setState(() => _logic.busy = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context)!;
    return Theme(
      data: AppTheme.dark(),
      child: Scaffold(
        backgroundColor: AppColors.ink,
        appBar: AppBar(
          backgroundColor: AppColors.ink,
          elevation: 0,
          foregroundColor: Colors.white,
          title: Text(_logic.signUpMode ? l10n.signUp : l10n.signIn),
        ),
        body: SafeArea(
          child: ListView(
            padding: const EdgeInsets.fromLTRB(20, 12, 20, 28),
            children: [
              Text(
                _logic.signUpMode ? l10n.authSignUpTitle : l10n.authSignInTitle,
                style: const TextStyle(
                  color: Colors.white,
                  fontSize: 22,
                  fontWeight: FontWeight.w800,
                ),
              ),
              const SizedBox(height: 6),
              Text(
                l10n.authSubtitle,
                style: const TextStyle(color: AppColors.muted, fontSize: 13),
              ),
              const SizedBox(height: 22),
              _field(
                label: l10n.authEmailLabel,
                hint: 'name@example.com',
                keyboardType: TextInputType.emailAddress,
                onChanged: (value) => _logic.email = value,
                autofocus: true,
              ),
              const SizedBox(height: 14),
              _field(
                label: l10n.authPasswordLabel,
                hint: l10n.authPasswordHint,
                obscure: true,
                onChanged: (value) => _logic.password = value,
              ),
              if (_logic.errorMessage != null) ...[
                const SizedBox(height: 12),
                Row(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    const Icon(
                      Icons.error_outline,
                      color: Color(0xFFFF6B6B),
                      size: 16,
                    ),
                    const SizedBox(width: 6),
                    Expanded(
                      child: Text(
                        _logic.errorMessage!,
                        style: const TextStyle(
                          color: Color(0xFFFF6B6B),
                          fontSize: 13,
                        ),
                      ),
                    ),
                  ],
                ),
              ],
              const SizedBox(height: 22),
              SizedBox(
                height: 48,
                child: FilledButton(
                  style: FilledButton.styleFrom(
                    backgroundColor: AppColors.blue,
                    shape: RoundedRectangleBorder(
                      borderRadius: BorderRadius.circular(24),
                    ),
                  ),
                  onPressed: _logic.busy ? null : _submit,
                  child: _logic.busy
                      ? const SizedBox(
                          width: 18,
                          height: 18,
                          child: CircularProgressIndicator(
                            strokeWidth: 2,
                            color: Colors.white,
                          ),
                        )
                      : Text(
                          _logic.signUpMode ? l10n.signUp : l10n.signIn,
                          style: const TextStyle(
                            fontSize: 15,
                            fontWeight: FontWeight.w700,
                          ),
                        ),
                ),
              ),
              const SizedBox(height: 14),
              TextButton(
                onPressed: _logic.busy
                    ? null
                    : () => setState(() => _logic.toggleMode()),
                child: Text(
                  _logic.signUpMode
                      ? l10n.authSwitchToSignIn
                      : l10n.authSwitchToSignUp,
                  style: const TextStyle(
                    color: AppColors.blueSoft,
                    fontSize: 13,
                  ),
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }

  Widget _field({
    required String label,
    required String hint,
    required ValueChanged<String> onChanged,
    bool obscure = false,
    bool autofocus = false,
    TextInputType? keyboardType,
  }) {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Text(
          label,
          style: const TextStyle(
            color: AppColors.muted,
            fontSize: 12,
            fontWeight: FontWeight.w700,
          ),
        ),
        const SizedBox(height: 6),
        TextField(
          autofocus: autofocus,
          obscureText: obscure,
          keyboardType: keyboardType,
          onChanged: onChanged,
          style: const TextStyle(color: Colors.white, fontSize: 15),
          decoration: InputDecoration(
            hintText: hint,
            hintStyle: const TextStyle(color: Color(0xFF6C7280), fontSize: 14),
            filled: true,
            fillColor: AppColors.card,
            contentPadding: const EdgeInsets.symmetric(
              horizontal: 14,
              vertical: 14,
            ),
            border: OutlineInputBorder(
              borderRadius: BorderRadius.circular(12),
              borderSide: BorderSide.none,
            ),
          ),
        ),
      ],
    );
  }
}