using Api.SeaHavenIndustries.Infrastructure;
using Data.SeaHavenIndustries;
using FluentAssertions;
using Microsoft.AspNetCore.Identity;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Options;
using Moq;
using SeaHaven.DataServices.Interfaces;
using SeaHaven.Services.Configuration;
using SeaHaven.Services.DTOs;
using SeaHaven.Services.Helpers;
using SeaHaven.Services.Implementation;
using SeaHaven.Services.Interfaces;
using Xunit;

namespace Api.SeaHavenIndustries.Tests;

/// <summary>
/// Exercises the password rule through the same Identity registration the API
/// host uses, so these assertions describe the rule that runs in production.
/// </summary>
public sealed class PasswordPolicyTests : IAsyncDisposable
{
    private const string CurrentPassword = "Current1!";
    private readonly ServiceProvider _provider;
    private readonly AsyncServiceScope _scope;

    public PasswordPolicyTests()
    {
        var services = new ServiceCollection();
        services.AddLogging();
        services.AddDbContext<ApplicationDbContext>(options =>
            options.UseInMemoryDatabase(Guid.NewGuid().ToString()));
        services.AddSeaHavenIdentity();
        _provider = services.BuildServiceProvider();
        _scope = _provider.CreateAsyncScope();
    }

    private UserManager<ApplicationUser> UserManager =>
        _scope.ServiceProvider.GetRequiredService<UserManager<ApplicationUser>>();

    [Theory]
    [InlineData("Ab1!x", "PasswordTooShort")]
    [InlineData("abc12!", "PasswordRequiresUpper")]
    [InlineData("Abcde!", "PasswordRequiresDigit")]
    [InlineData("Abcde1", "PasswordRequiresNonAlphanumeric")]
    public async Task Policy_RejectsPasswordMissingOneRule(string password, string expectedCode)
    {
        var user = new ApplicationUser { UserName = "policy@example.com", Email = "policy@example.com" };

        var errors = await ValidateAsync(user, password);

        errors.Select(error => error.Code).Should().Equal(expectedCode);
    }

    [Theory]
    [InlineData("Abc1!x")]
    [InlineData("ABC12!")]
    public async Task Policy_AcceptsSixCharacterPasswordMeetingEveryRule(string password)
    {
        var user = new ApplicationUser { UserName = "policy@example.com", Email = "policy@example.com" };

        var errors = await ValidateAsync(user, password);

        errors.Should().BeEmpty();
    }

    [Fact]
    public void Registration_AppliesSharedPolicyOptions()
    {
        var options = _scope.ServiceProvider.GetRequiredService<IOptions<IdentityOptions>>().Value.Password;

        options.RequiredLength.Should().Be(6);
        options.RequireUppercase.Should().BeTrue();
        options.RequireDigit.Should().BeTrue();
        options.RequireNonAlphanumeric.Should().BeTrue();
        options.RequireLowercase.Should().BeFalse();
    }

    [Fact]
    public async Task ChangePassword_WrongCurrentPassword_IsRejectedBeforeNewPasswordIsEvaluated()
    {
        var user = await CreateUserAsync();
        var service = NewAuthenticationService();

        var result = await service.ChangePasswordAsync(user.Id, "Wrong1!", "weak", CancellationToken.None);

        result.Status.Should().Be(ChangePasswordStatus.CurrentPasswordIncorrect);
        (await UserManager.CheckPasswordAsync(user, CurrentPassword)).Should().BeTrue();
    }

    [Fact]
    public async Task ChangePassword_CorrectCurrentPasswordAndWeakNewPassword_IsRejectedByPolicy()
    {
        var user = await CreateUserAsync();
        var service = NewAuthenticationService();

        var result = await service.ChangePasswordAsync(user.Id, CurrentPassword, "abcdef", CancellationToken.None);

        result.Status.Should().Be(ChangePasswordStatus.PasswordRejected);
        (await UserManager.CheckPasswordAsync(user, CurrentPassword)).Should().BeTrue();
    }

    [Fact]
    public async Task ChangePassword_CorrectCurrentPasswordAndCompliantNewPassword_ChangesPassword()
    {
        var user = await CreateUserAsync();
        var service = NewAuthenticationService();

        var result = await service.ChangePasswordAsync(user.Id, CurrentPassword, "Next2@x", CancellationToken.None);

        result.Status.Should().Be(ChangePasswordStatus.Succeeded);
        var reloaded = await UserManager.FindByIdAsync(user.Id);
        (await UserManager.CheckPasswordAsync(reloaded!, "Next2@x")).Should().BeTrue();
    }

    [Theory]
    [InlineData("ConcurrencyFailure")]
    [InlineData("PasswordMismatch")]
    [InlineData("DefaultError")]
    public async Task ChangePassword_NonPolicyIdentityFailure_IsNotReportedAsAWeakPassword(string code)
    {
        var user = new ApplicationUser { Id = "member-1", UserName = "member@example.com" };
        var userManager = new Mock<UserManager<ApplicationUser>>(
            Mock.Of<IUserStore<ApplicationUser>>(), null!, null!, null!, null!, null!, null!, null!, null!);
        userManager.Setup(m => m.FindByIdAsync(user.Id)).ReturnsAsync(user);
        userManager.Setup(m => m.CheckPasswordAsync(user, CurrentPassword)).ReturnsAsync(true);
        userManager.Setup(m => m.ChangePasswordAsync(user, CurrentPassword, "Next2@x"))
            .ReturnsAsync(IdentityResult.Failed(new IdentityError { Code = code, Description = "failed" }));
        var service = new AuthenticationService(
            userManager.Object,
            Microsoft.Extensions.Options.Options.Create(new JwtOptions { Secret = new string('x', 64) }),
            Mock.Of<IUserDataService>(),
            Mock.Of<IForgetPasswordDataService>(),
            Mock.Of<IPasswordResetEmailQueue>(),
            new InMemoryPasswordResetThrottle(TimeProvider.System),
            TimeProvider.System,
            Mock.Of<ISessionStampService>());

        var result = await service.ChangePasswordAsync(user.Id, CurrentPassword, "Next2@x", CancellationToken.None);

        result.Status.Should().Be(ChangePasswordStatus.Failed);
    }

    [Theory]
    [InlineData("PasswordTooShort", true)]
    [InlineData("PasswordRequiresUpper", true)]
    [InlineData("PasswordRequiresDigit", true)]
    [InlineData("PasswordRequiresNonAlphanumeric", true)]
    [InlineData("ConcurrencyFailure", false)]
    [InlineData("PasswordMismatch", false)]
    public void IsPolicyRejection_MatchesOnlyThePasswordRuleCodes(string code, bool expected)
    {
        IdentityPasswordPolicy.IsPolicyRejection(IdentityResult.Failed(new IdentityError { Code = code }))
            .Should().Be(expected);
    }

    [Fact]
    public async Task ChangePassword_CancelledToken_Throws()
    {
        var service = NewAuthenticationService();
        using var cancellation = new CancellationTokenSource();
        cancellation.Cancel();

        var act = () => service.ChangePasswordAsync("any", CurrentPassword, "Next2@x", cancellation.Token);

        await act.Should().ThrowAsync<OperationCanceledException>();
    }

    [Fact]
    public async Task ResetPassword_WeakPassword_IsRejectedAndKeepsCode()
    {
        var user = await CreateUserAsync();
        var forget = new Mock<IForgetPasswordDataService>();
        var salt = PasswordResetCodeSecrets.NewSalt();
        forget.Setup(f => f.GetByEmailAsync(user.Email!, It.IsAny<CancellationToken>()))
            .ReturnsAsync(new ForgetPasswordCode
            {
                Id = 7,
                Email = user.Email!,
                UserId = user.Id,
                CodeSalt = salt,
                CodeHash = PasswordResetCodeSecrets.Hash(PasswordResetCodeSecrets.DeriveKey(new string('x', 64)), salt, "123456"),
                ExpiresAtUtc = DateTime.UtcNow.AddMinutes(10)
            });
        forget.Setup(f => f.TryConsumeAttemptAsync(7, It.IsAny<int>(), It.IsAny<DateTime>(), It.IsAny<CancellationToken>()))
            .ReturnsAsync(true);
        var service = NewAuthenticationService(forget);

        var reset = await service.ResetPasswordAsync(user.Email!, "123456", "abcdef", CancellationToken.None);

        reset.Should().BeFalse();
        (await UserManager.CheckPasswordAsync(user, CurrentPassword)).Should().BeTrue();
        forget.Verify(f => f.RemoveByEmailAsync(It.IsAny<string>(), It.IsAny<CancellationToken>()), Times.Never);
        forget.Verify(f => f.RefundAttemptAsync(7, It.IsAny<CancellationToken>()), Times.Once);
    }

    private async Task<IReadOnlyList<IdentityError>> ValidateAsync(ApplicationUser user, string password)
    {
        var errors = new List<IdentityError>();
        foreach (var validator in UserManager.PasswordValidators)
        {
            var result = await validator.ValidateAsync(UserManager, user, password);
            errors.AddRange(result.Errors);
        }

        return errors;
    }

    private async Task<ApplicationUser> CreateUserAsync()
    {
        var user = new ApplicationUser { UserName = "member@example.com", Email = "member@example.com" };
        var created = await UserManager.CreateAsync(user, CurrentPassword);
        created.Succeeded.Should().BeTrue();
        return user;
    }

    private AuthenticationService NewAuthenticationService(Mock<IForgetPasswordDataService>? forget = null) =>
        new(
            UserManager,
            Microsoft.Extensions.Options.Options.Create(new JwtOptions { Secret = new string('x', 64) }),
            Mock.Of<IUserDataService>(),
            (forget ?? new Mock<IForgetPasswordDataService>()).Object,
            Mock.Of<IPasswordResetEmailQueue>(),
            new InMemoryPasswordResetThrottle(TimeProvider.System),
            TimeProvider.System,
            Mock.Of<ISessionStampService>());

    public async ValueTask DisposeAsync()
    {
        await _scope.DisposeAsync();
        await _provider.DisposeAsync();
    }
}