namespace PhotoShare.Client.Core.Commands
{
    using System;
    using System.Collections.Generic;
    using System.ComponentModel.DataAnnotations;

    using Contracts;
    using PhotoShare.Client.Core.Dtos;
    using PhotoShare.Services.Contracts;

    public class RegisterUserCommand : ICommand
    {
        private readonly IUserService userService;

        public RegisterUserCommand(IUserService userService)
        {
            this.userService = userService;
        }

        // RegisterUser <username> <password> <repeat-password> <email>
        public string Execute(string[] data)
        {
            var username = data[0];
            var pass = data[1];
            var repeatedPass = data[2];
            var email = data[3];

            var userExist = this.userService.Exists(username);

            if (userExist)
            {
                throw new InvalidOperationException($"Username [{username}] is already taken!");
            }

            if (!pass.Equals(repeatedPass))
            {
                throw new ArgumentException("Passwords do not match!");
            }



            var registerUserDto = new RegisterUserDto { Username = username, Password = pass, Email = email };

            if (!IsValid(registerUserDto))
            {
                throw new ArgumentException("Invalid arguments inserted!");
            }

            this.userService.Register(username, pass, email);

            return $"User [{username}] was registered successfully!";
        }

        private bool IsValid(object obj)
        {
            var validationContext = new ValidationContext(obj);
            var validationResults = new List<ValidationResult>();

            return Validator.TryValidateObject(obj, validationContext, validationResults, true);
        }
    }
}