// Copyright (c) 2020 Tudor Stanciu

using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.DependencyInjection;
using System;
using System.Threading.Tasks;
using Tuitio.Application.Services.Abstractions;
using Tuitio.Application.Tests.Fixtures;
using Tuitio.Domain.Data.DbContexts;
using Tuitio.Domain.Models.Account;
using Xunit;

namespace Tuitio.Application.Tests
{
    public class UserServiceTests : IClassFixture<DependencyInjectionFixture>, IDisposable
    {
        private readonly IServiceScope _tuitioScope;
        private readonly IUserService _userService;

        public UserServiceTests(DependencyInjectionFixture fixture)
        {
            _tuitioScope = fixture.ServiceProvider.GetRequiredService<IServiceScopeFactory>().CreateScope();
            _userService = _tuitioScope.ServiceProvider.GetRequiredService<IUserService>();
        }

        public void Dispose()
        {
            _tuitioScope.Dispose();
        }

        [Fact]
        public async Task Login_ShouldThrowArgumentExceptionIfUserNameIsNullOrEmptyString()
        {
            // Arrange
            var userName = "";
            var password = "";

            // Act

            // Assert
            await Assert.ThrowsAsync<ArgumentException>(nameof(userName), () => _userService.Login(userName, password));
            await Assert.ThrowsAsync<ArgumentException>(nameof(userName), () => _userService.Login(null, password));
        }

        [Fact]
        public async Task Login_ShouldThrowArgumentExceptionIfPasswordIsNullOrEmptyString()
        {
            // Arrange
            var userName = "tuitio.test.user";
            var password = "";

            // Act

            // Assert
            await Assert.ThrowsAsync<ArgumentException>(nameof(password), () => _userService.Login(userName, password));
            await Assert.ThrowsAsync<ArgumentException>(nameof(password), () => _userService.Login(userName, null));
        }

        [Fact]
        public async Task Login_ShouldReturnAValidToken()
        {
            // Arrange
            var userName = "tuitio.user";
            var password = "pass123";

            // Act
            var result = await _userService.Login(userName, password);

            // Assert
            Assert.NotNull(result);
            Assert.NotNull(result.Token);
            Assert.NotEmpty(result.Raw);
            Assert.Equal(userName, result.Token.UserName);
            Assert.True(result.Token.TokenId != Guid.Empty, "Token id cannot be an empty guid.");
            Assert.NotEmpty(result.Token.LockStamp);
            Assert.True(result.Token.ExpiresIn > 0, "Token expiration must be a positive number.");
            Assert.True((DateTime.UtcNow - result.Token.CreatedAt).TotalMinutes <= 1, "Token creation date must be within the last minute.");
        }

        [Fact]
        public async Task Login_ShouldSetCorrectLastLoginDate()
        {
            // Arrange
            var userName = "tuitio.user";
            var password = "pass123";
            var dbContext = _tuitioScope.ServiceProvider.GetRequiredService<TuitioDbContext>();
            await _userService.Login(userName, password);

            // Act
            var userFromDb = await dbContext.Users.FirstOrDefaultAsync(z => z.UserName == userName);

            // Assert
            Assert.NotNull(userFromDb);
            Assert.True(userFromDb.LastLoginDate.HasValue, "Last login date cannot be null after user login");
            Assert.True((DateTime.UtcNow - userFromDb.LastLoginDate.Value).TotalMinutes <= 1, "Last login date must be within the last minute.");
        }

        [Fact]
        public async Task Login_ShouldSaveTokenInDatabase()
        {
            // Arrange
            var userName = "tuitio.user";
            var password = "pass123";
            var dbContext = _tuitioScope.ServiceProvider.GetRequiredService<TuitioDbContext>();
            var loginResult = await _userService.Login(userName, password);

            // Act
            var userTokenFromDb = await dbContext.UserTokens.FirstOrDefaultAsync(z => z.TokenId == loginResult.Token.TokenId);

            // Assert
            Assert.NotNull(userTokenFromDb);
            Assert.True(loginResult.Token.TokenId != Guid.Empty, "Token id cannot be an empty guid.");
            Assert.True((DateTime.UtcNow - userTokenFromDb.ValidFrom).TotalMinutes <= 1, "Token valid from date must be within the last minute.");
            Assert.True(userTokenFromDb.ValidUntil > DateTime.UtcNow, "Token valid until date must be greater than the current date.");
        }

        [Fact]
        public async Task Login_ShouldReturnNullResultForWrongCredentials()
        {
            // Arrange
            var userName = "tuitio.user";
            var password = "wrong_password";

            // Act
            var result = await _userService.Login(userName, password);

            // Assert
            Assert.Null(result);
        }

        [Fact]
        public async Task Authorize_ShouldReturnAValidToken()
        {
            // Arrange
            var userName = "tuitio.user";
            var password = "pass123";
            var loginResult = await _userService.Login(userName, password);

            // Act
            var result = _userService.Authorize(loginResult.Raw);

            // Assert
            Assert.NotNull(result);
            Assert.Equal(userName, result.UserName);
            Assert.NotNull(result.SecurityStamp);
            Assert.NotNull(result.LockStamp);
            Assert.True(result.TokenId != Guid.Empty, "Token id cannot be an empty guid.");
            Assert.True(result.ExpiresIn > 0, "Token expiration must be a positive number.");
        }

        [Fact]
        public void Authorize_ShouldReturnNull()
        {
            // Arrange
            var unauthorizedToken = "unauthorized-token";

            // Act
            var result = _userService.Authorize(unauthorizedToken);

            // Assert
            Assert.Null(result);
        }

        [Fact]
        public async Task Logout_ShouldSuccessfullyLogoutTheUser()
        {
            // Arrange
            var userName = "tuitio.user";
            var password = "pass123";
            var loginResult = await _userService.Login(userName, password);

            // Act
            LogoutResult result;
            using (var scope = _tuitioScope.ServiceProvider.CreateScope())
            {
                var newUserService = scope.ServiceProvider.GetRequiredService<IUserService>();
                result = await newUserService.Logout(loginResult.Raw);
            }

            // Assert
            Assert.NotNull(result);
            Assert.Equal(userName, result.UserName);
            Assert.True((DateTime.UtcNow - result.LogoutDate).TotalMinutes <= 1, "Logout date must be within the last minute.");
        }

        [Fact]
        public async Task Logout_ShouldReturnNullResultForUnauthenticatedToken()
        {
            // Arrange
            var unauthenticatedToken = "unauthenticated-token";

            // Act
            var result = await _userService.Logout(unauthenticatedToken);

            // Assert
            Assert.Null(result);
        }
    }
}