using IdentityServer.Application.Services.Abstractions;
using IdentityServer.Application.Stores;
using IdentityServer.Domain.Abstractions;
using IdentityServer.Domain.Entities;
using IdentityServer.Domain.Models;
using IdentityServer.Domain.Repositories;
using System;
using System.Threading.Tasks;

namespace IdentityServer.Application.Services
{
    internal class UserService : IUserService
    {
        private readonly ITokenStore _securityStore;
        private readonly IIdentityRepository _identityRepository;
        private readonly ITokenService _tokenService;
        private readonly IConfigProvider _configProvider;
        private readonly IHashingService _hashingService;

        public UserService(ITokenStore securityStore, IIdentityRepository identityRepository, ITokenService tokenService, IConfigProvider configProvider, IHashingService hashingService)
        {
            _securityStore=securityStore;
            _identityRepository=identityRepository;
            _tokenService=tokenService;
            _configProvider=configProvider;
            _hashingService=hashingService;
        }

        public async Task<Token> Authenticate(string userName, string password)
        {
            var passwordHash = _hashingService.HashSha256(password);
            var user = await _identityRepository.GetUser(userName, passwordHash);
            var valid = ValidateUser(user);
            if (!valid)
                return null;

            var token = _tokenService.GenerateToken(user);
            _securityStore.SetToken(token, user.UserId);
            await _identityRepository.UpdateUserAfterAuthentication(user, token);

            return token;
        }

        public TokenCore Authorize(string token)
        {
            var tokenCore = _securityStore.ValidateAndGetTokenCore(token);
            if (tokenCore == null)
                return null;

            return tokenCore;
        }

        private bool ValidateUser(AppUser user)
        {
            if (user == null)
                return false;

            if (user.FailedLoginAttempts.HasValue && user.FailedLoginAttempts.Value > _configProvider.Restrictions.MaxFailedLoginAttempts)
                return false;

            return true;
        }
    }
}