import 'package:app_sensor/login_page.dart';
import 'package:flutter/material.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:firebase_auth/firebase_auth.dart';

class SignUpPage extends StatefulWidget {
  @override
  _SignUpPageState createState() => _SignUpPageState();
}

class _SignUpPageState extends State<SignUpPage> {
  final TextEditingController nameController = TextEditingController();
  final TextEditingController emailController = TextEditingController();
  final TextEditingController passwordController = TextEditingController();

  bool isEmailValid = false;
  bool isLoading = false;
  bool _obscurePassword = true;

  @override
  void initState() {
    super.initState();
    emailController.addListener(_validateEmail);
  }

  @override
  void dispose() {
    emailController.removeListener(_validateEmail);
    emailController.dispose();
    nameController.dispose();
    passwordController.dispose();
    super.dispose();
  }

  void _validateEmail() {
    setState(() {
      isEmailValid = emailController.text.endsWith('@gmail.com');
    });
  }

  Future<void> _saveUserData(String email, String password) async {
    SharedPreferences prefs = await SharedPreferences.getInstance();
    await prefs.setString('email', email);
    await prefs.setString('password', password);
  }

  Future<void> _registerUser() async {
    String email = emailController.text.trim();
    String password = passwordController.text.trim();
    String name = nameController.text.trim();

    if (name.isEmpty || password.isEmpty) {
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text('Nama dan Password tidak boleh kosong')),
      );
      return;
    }

    setState(() {
      isLoading = true;
    });

    try {
      await FirebaseAuth.instance.createUserWithEmailAndPassword(
        email: email,
        password: password,
      );

      await _saveUserData(email, password);

      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text('Registrasi berhasil! Silakan login.')),
      );

      Navigator.pushReplacement(
        context,
        MaterialPageRoute(builder: (_) => LoginPage()),
      );
    } on FirebaseAuthException catch (e) {
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text(e.message ?? 'Terjadi kesalahan saat registrasi')),
      );
    } finally {
      setState(() {
        isLoading = false;
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Container(
        width: double.infinity,
        height: double.infinity,
        decoration: const BoxDecoration(
          gradient: LinearGradient(
            colors: [
              Color(0xFFB3E5FC), // biru pastel muda
              Color(0xFFE1F5FE), // biru pastel pucat
            ],
            begin: Alignment.topLeft,
            end: Alignment.bottomRight,
          ),
        ),
        padding: const EdgeInsets.all(20.0),
        child: SingleChildScrollView(
          child: Column(
            children: [
              SizedBox(height: 60),
              Icon(Icons.person_add, size: 80, color: Colors.blueGrey[800]),
              SizedBox(height: 10),
              Text(
                "Buat Akun Baru",
                style: TextStyle(
                  fontSize: 24,
                  fontWeight: FontWeight.bold,
                  color: Colors.blueGrey[800],
                ),
              ),
              SizedBox(height: 30),
              Container(
                padding: EdgeInsets.all(20),
                decoration: BoxDecoration(
                  color: Colors.white.withOpacity(0.95),
                  borderRadius: BorderRadius.circular(16),
                  boxShadow: [
                    BoxShadow(
                      color: Colors.blueGrey.withOpacity(0.1),
                      blurRadius: 20,
                      offset: Offset(0, 10),
                    ),
                  ],
                ),
                child: Column(
                  children: [
                    TextField(
                      controller: nameController,
                      decoration: InputDecoration(
                        labelText: 'Nama',
                        prefixIcon: Icon(Icons.person, color: Colors.blueGrey),
                        border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
                      ),
                    ),
                    SizedBox(height: 15),
                    TextField(
                      controller: emailController,
                      keyboardType: TextInputType.emailAddress,
                      decoration: InputDecoration(
                        labelText: 'Email',
                        prefixIcon: Icon(Icons.email, color: Colors.blueGrey),
                        border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
                      ),
                    ),
                    SizedBox(height: 15),
                    TextField(
                      controller: passwordController,
                      obscureText: _obscurePassword,
                      decoration: InputDecoration(
                        labelText: 'Password',
                        prefixIcon: Icon(Icons.lock, color: Colors.blueGrey),
                        suffixIcon: IconButton(
                          icon: Icon(
                            _obscurePassword ? Icons.visibility_off : Icons.visibility,
                            color: Colors.blueGrey,
                          ),
                          onPressed: () {
                            setState(() {
                              _obscurePassword = !_obscurePassword;
                            });
                          },
                        ),
                        border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
                      ),
                    ),
                    if (!isEmailValid && emailController.text.isNotEmpty)
                      Padding(
                        padding: const EdgeInsets.only(top: 10),
                        child: Text(
                          'Email harus berakhiran @gmail.com',
                          style: TextStyle(color: Colors.redAccent),
                        ),
                      ),
                    SizedBox(height: 20),
                    ElevatedButton(
                      onPressed: isEmailValid && !isLoading ? _registerUser : null,
                      style: ElevatedButton.styleFrom(
                        backgroundColor: Color(0xFF81D4FA),
                        minimumSize: Size(double.infinity, 48),
                        shape: RoundedRectangleBorder(
                          borderRadius: BorderRadius.circular(12),
                        ),
                      ),
                      child: isLoading
                          ? CircularProgressIndicator(color: Colors.white)
                          : Text(
                              'DAFTAR',
                              style: TextStyle(
                                fontSize: 16,
                                fontWeight: FontWeight.bold,
                                color: Colors.white,
                                letterSpacing: 1.1,
                              ),
                            ),
                    ),
                    SizedBox(height: 10),
                    OutlinedButton(
                      onPressed: () {
                        Navigator.pop(context);
                      },
                      style: OutlinedButton.styleFrom(
                        minimumSize: Size(double.infinity, 48),
                        side: BorderSide(color: Colors.blueGrey),
                        shape: RoundedRectangleBorder(
                          borderRadius: BorderRadius.circular(12),
                        ),
                      ),
                      child: Text(
                        'KEMBALI',
                        style: TextStyle(
                          fontWeight: FontWeight.bold,
                          color: Colors.blueGrey[700],
                        ),
                      ),
                    ),
                  ],
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}