import 'dart:async';
import 'dart:io';

import 'package:flutter/material.dart';
import 'package:learn_fazz/app_config.dart';
import 'package:learn_fazz/models/login_result.dart';
import 'package:learn_fazz/pages/dashboard_page.dart';
import 'package:learn_fazz/repositories/auth_repository.dart';
import 'package:learn_fazz/widgets/image_picker_bottom_sheet.dart';
import '../assets/learn_fazz_icons.dart';

class RegisterFormPage extends StatefulWidget {
  static String tag = '/register-form-page';

  static String kNoImageErrorMessage =
      'Please choose image first to be able to proceed.';

  @override
  _RegisterFormPageState createState() => _RegisterFormPageState();
}

class _RegisterFormPageState extends State<RegisterFormPage> {
  final GlobalKey<FormState> _formKey = GlobalKey<FormState>();
  final GlobalKey<FormFieldState<String>> _passKey =
      GlobalKey<FormFieldState<String>>();
  final Color borderColor = Colors.black.withOpacity(0.4);
  bool passwordVisible = true;
  bool confirmPasswordVisible = true;

  bool _isSubmitting = false;

  String _name;
  String _email;
  String _identificationNumber;
  String _password;
  String _passwordConfirmation;
  String _role;
  File _imageFile;

  @override
  Widget build(BuildContext context) {
    final Widget logo = _imageFile == null
        ? Container(
            child: CircleAvatar(
              radius: 72.0,
              backgroundColor: Colors.blue,
              foregroundColor: Colors.white,
              child: const Icon(LearnFazz.camera, size: 50.0),
            ),
            padding: const EdgeInsets.all(2.0), // border width
            decoration: const BoxDecoration(
              color: Colors.white, // border color
              shape: BoxShape.circle,
            ),
          )
        : CircleAvatar(
            radius: 72.0,
            child: ClipOval(child: Image.file(_imageFile)),
          );

    final Widget addPhotoLabel = InkWell(
      child: const Text(
        'Add Photo',
        key: Key('addPhotoLabel'),
        style: TextStyle(
            fontWeight: FontWeight.bold,
            fontSize: 18.0,
            decoration: TextDecoration.underline,
            color: Colors.white),
        textAlign: TextAlign.center,
      ),
      onTap: () async {
        final File _choosenImage = await showImagePickerBottomSheet(context);
        setState(() => _imageFile = _choosenImage);
      },
    );

    final TextFormField name = TextFormField(
      autofocus: true,
      validator: (String value) {
        if (value.isEmpty) {
          return 'Name cannot be empty';
        }
      },
      onSaved: (String val) => _name = val,
      style: const TextStyle(color: Colors.black, fontSize: 16.0),
      decoration: InputDecoration(
        fillColor: Colors.white,
        filled: true,
        hintText: 'Name',
        contentPadding: const EdgeInsets.fromLTRB(20.0, 10.0, 20.0, 10.0),
        border: OutlineInputBorder(
          borderRadius: BorderRadius.circular(32.0),
        ),
        enabledBorder: OutlineInputBorder(
          borderRadius: BorderRadius.circular(32.0),
          borderSide: BorderSide(width: 1.5, color: borderColor),
        ),
        prefixIcon: const Icon(LearnFazz.person_outline),
      ),
    );

    final TextFormField email = TextFormField(
      keyboardType: TextInputType.emailAddress,
      validator: (String value) {
        if (value.isEmpty) {
          return 'Email cannot be empty';
        } else if (value.isNotEmpty && !value.contains('@gmail.')) {
          return 'Invalid email address';
        }
      },
      onSaved: (String val) => _email = val,
      style: const TextStyle(color: Colors.black, fontSize: 16.0),
      decoration: InputDecoration(
        fillColor: Colors.white,
        filled: true,
        hintText: 'Email',
        contentPadding: const EdgeInsets.fromLTRB(20.0, 10.0, 20.0, 10.0),
        border: OutlineInputBorder(borderRadius: BorderRadius.circular(32.0)),
        enabledBorder: OutlineInputBorder(
          borderRadius: BorderRadius.circular(32.0),
          borderSide: BorderSide(width: 1.5, color: borderColor),
        ),
        prefixIcon: const Icon(LearnFazz.mail),
      ),
    );

    final TextFormField idNumber = TextFormField(
      keyboardType: TextInputType.number,
      validator: (String value) {
        if (value.isEmpty) {
          return 'Identification number cannot be empty';
        }
      },
      onSaved: (String identificationNumber) =>
          _identificationNumber = identificationNumber,
      style: const TextStyle(color: Colors.black, fontSize: 16.0),
      decoration: InputDecoration(
        fillColor: Colors.white,
        filled: true,
        hintText: 'Identification Number',
        contentPadding: const EdgeInsets.fromLTRB(20.0, 10.0, 20.0, 10.0),
        border: OutlineInputBorder(
          borderRadius: BorderRadius.circular(32.0),
        ),
        enabledBorder: OutlineInputBorder(
          borderRadius: BorderRadius.circular(32.0),
          borderSide: BorderSide(width: 1.5, color: borderColor),
        ),
        prefixIcon: const Icon(LearnFazz.id_card),
      ),
    );

    final TextFormField password = TextFormField(
      validator: (String value) {
        if (value.isEmpty) {
          return 'Password cannot be empty';
        } else if (value.length < 8) {
          return 'Password should\'ve at least 8 characters';
        }
      },
      onSaved: (String password) => _password = password,
      style: const TextStyle(color: Colors.black, fontSize: 16.0),
      obscureText: passwordVisible,
      key: _passKey,
      decoration: InputDecoration(
        fillColor: Colors.white,
        filled: true,
        hintText: 'Password',
        contentPadding: const EdgeInsets.fromLTRB(20.0, 10.0, 20.0, 10.0),
        border: OutlineInputBorder(
          borderRadius: BorderRadius.circular(32.0),
        ),
        enabledBorder: OutlineInputBorder(
          borderRadius: BorderRadius.circular(32.0),
          borderSide: BorderSide(width: 1.5, color: borderColor),
        ),
        prefixIcon: const Icon(LearnFazz.lock),
        suffixIcon: IconButton(
            icon: Icon(passwordVisible ? LearnFazz.eye : Icons.visibility_off),
            onPressed: () {
              setState(() {
                passwordVisible
                    ? passwordVisible = false
                    : passwordVisible = true;
              });
            }),
      ),
    );

    final TextFormField confirmPassword = TextFormField(
      validator: (String value) {
        final String password = _passKey.currentState.value;
        return (value == password) ? null : 'Password doesn\'t match';
      },
      onSaved: (String passwordConfirmation) =>
          _passwordConfirmation = passwordConfirmation,
      style: const TextStyle(color: Colors.black, fontSize: 16.0),
      obscureText: confirmPasswordVisible,
      decoration: InputDecoration(
        fillColor: Colors.white,
        filled: true,
        hintText: 'Confirm Password',
        contentPadding: const EdgeInsets.fromLTRB(20.0, 10.0, 20.0, 10.0),
        border: OutlineInputBorder(
          borderRadius: BorderRadius.circular(32.0),
        ),
        enabledBorder: OutlineInputBorder(
          borderRadius: BorderRadius.circular(32.0),
          borderSide: BorderSide(width: 1.5, color: borderColor),
        ),
        prefixIcon: const Icon(LearnFazz.lock),
        suffixIcon: IconButton(
          icon: Icon(
              confirmPasswordVisible ? LearnFazz.eye : Icons.visibility_off),
          onPressed: () {
            setState(() {
              confirmPasswordVisible
                  ? confirmPasswordVisible = false
                  : confirmPasswordVisible = true;
            });
          },
        ),
      ),
    );

    final Widget bottomNavigationBar =
        _isSubmitting ? LinearProgressIndicator() : null;

    return Scaffold(
      body: Builder(
        builder: (BuildContext context) => Container(
            decoration: const BoxDecoration(
                image: DecorationImage(
              image: AssetImage(
                  'lib/assets/images/blue-white-pattern-background.png'),
              fit: BoxFit.cover,
            )),
            child: Form(
              key: _formKey,
              child: ListView(
                padding: const EdgeInsets.only(
                    top: 100.0, left: 45.0, right: 45.0, bottom: 40.0),
                children: <Widget>[
                  logo,
                  const SizedBox(height: 10.0),
                  addPhotoLabel,
                  const SizedBox(height: 30.0),
                  name,
                  const SizedBox(height: 8.0),
                  email,
                  const SizedBox(height: 8.0),
                  idNumber,
                  const SizedBox(height: 8.0),
                  password,
                  const SizedBox(height: 8.0),
                  confirmPassword,
                  const SizedBox(height: 30.0),
                  InkWell(
                    key: const Key('registerButton'),
                    onTap: () => _validateThenPostToBackend(context),
                    child: Container(
                      height: 50.0,
                      decoration: BoxDecoration(
                        color: _isSubmitting
                            ? Colors.grey
                            : const Color(0xFF3A8FF3),
                        borderRadius: BorderRadius.circular(30.0),
                      ),
                      child: const Center(
                        child: Text(
                          'Register',
                          style: TextStyle(fontSize: 18.0, color: Colors.white),
                        ),
                      ),
                    ),
                  ),
                ],
              ),
            )),
      ),
      bottomNavigationBar: bottomNavigationBar,
    );
  }

  Future<void> _validateThenPostToBackend(BuildContext context) async {
    if (_isSubmitting) {
      return;
    }
    if (_formKey.currentState.validate()) {
      setState(() => _isSubmitting = true);
      _formKey.currentState.save();
      try {
        if (_imageFile == null) {
          throw RegisterFormPage.kNoImageErrorMessage;
        }
        final AuthRepository authRepository =
            AppConfig.of(context).authRepository;
        final LoginResult response = await authRepository.register(
          name: _name,
          email: _email,
          identificationNumber: _identificationNumber,
          password: _password,
          passwordConfirmation: _passwordConfirmation,
          role: _role,
          photo: _imageFile,
        );
        Navigator.of(context).push<dynamic>(MaterialPageRoute<dynamic>(
          builder: (BuildContext context) => DashboardPage(user: response.user),
        ));
      } catch (e) {
        Scaffold.of(context).showSnackBar(SnackBar(
            content: Text(e.toString()), duration: const Duration(seconds: 5)));
      }
      setState(() => _isSubmitting = false);
    }
  }
}