using Acr.UserDialogs;
using Plas.Datas;
using Plas.Menus;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Xamarin.Forms;

namespace Plas.Login
{
    public class LoginPageViewModel : BaseViewModel
    {
        private string mUsername;
        public string Username
        {
            get { return mUsername; }
            set
            {
                SetProperty(ref mUsername, value);
                Validate();
            }
        }

        private string mPassword;
        public string Password
        {
            get { return mPassword; }
            set
            {
                SetProperty(ref mPassword, value);
                Validate();
            }
        }

        private bool mEnabledLoginButton;
        public bool EnabledLoginButton
        {
            get { return mEnabledLoginButton; }
            set { SetProperty(ref mEnabledLoginButton, value); }
        }

        public bool AlreadyLogin
        {
            get
            {
                if (Application.Current.Properties.ContainsKey("isLogin"))
                {
                    return (bool)Application.Current.Properties["isLogin"];
                }
                else
                {
                    return false;
                }
            }

            set
            {
                Application.Current.Properties["isLogin"] = value;
                Application.Current.SavePropertiesAsync();
            }
        }

        public Command LoginCommand { get; private set; }

        private LoginDataProvider mDataProvider;

        public LoginPageViewModel()
        {
            LoginCommand = new Command(async () => await LoginAsync());
            EnabledLoginButton = false;
            mDataProvider = new LoginDataProvider();
        }

        private async Task LoginAsync()
        {
            IsBusy = true;

            bool isAuthorize = false;
            try
            {
                var response = await mDataProvider.GetListAsync();
                if (response != null &&
                    response.UserList != null &&
                    response.UserList.Count > 0)
                {
                    var user = response.UserList.FirstOrDefault(i => i.UserName == Username);
                    if (user != null && user.Password == this.Password)
                    {
                        isAuthorize = true;
                    }
                }
            }
            catch (Exception ex)
            {
                Debug.WriteLine(ex);
            }

            if (isAuthorize)
            {
                AlreadyLogin = true;
                await LoginProcess();
            }
            else
            {
                UserDialogs.Instance.Alert("Invalid username or password",
                                           "Failed to login");
            }

            IsBusy = false;
        }

        private void Validate()
        {
            if (!string.IsNullOrEmpty(Username) && !string.IsNullOrEmpty(Password))
            {
                EnabledLoginButton = true;
            }
            else
            {
                EnabledLoginButton = false;
            }
        }

        public async Task LoginProcess()
        {
            var dataLoader = new DataLoader();
            var isSuccess = await dataLoader.LoadData();
            if (isSuccess)
            {
                Application.Current.MainPage = new MenuPage();
            }
            else
            {
                UserDialogs.Instance.Alert("Failed to load data", "Error");
            }
        }
    }
}