using FsCheck;
using FsCheck.Xunit;
using Microsoft.Extensions.Logging;
using MiAssessment.Core.Interfaces;
using MiAssessment.Core.Services;
using MiAssessment.Model.Models.System;
using Moq;
using Xunit;

namespace MiAssessment.Tests.Services;

/// <summary>
/// SystemService 属性测试
/// 验证系统配置服务的响应格式一致性
/// </summary>
public class SystemServicePropertyTests
{
    private readonly Mock<ILogger<SystemService>> _mockLogger = new();

    #region Property 8: 响应格式一致性 - GetAgreementAsync

    /// <summary>
    /// Property 8: GetAgreementAsync 返回包含 Content 属性的 AgreementDto
    /// *For any* GetAgreementAsync call, the returned AgreementDto SHALL have a Content property.
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.1, 16.1, 16.2, 16.3**
    /// </summary>
    [Property(MaxTest = 100)]
    public bool GetAgreementAsync_ReturnsAgreementDtoWithContentProperty(NonEmptyString content)
    {
        // Arrange
        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("user_agreement"))
            .ReturnsAsync(content.Get);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var result = service.GetAgreementAsync().GetAwaiter().GetResult();

        // Assert: 验证返回的 AgreementDto 包含 Content 属性且值正确
        return result != null && result.Content == content.Get;
    }

    /// <summary>
    /// Property 8: GetAgreementAsync 返回非空 DTO，即使配置值为空
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.1, 16.1, 16.2, 16.3**
    /// </summary>
    [Fact]
    public void GetAgreementAsync_ReturnsNonNullDto_WhenConfigValueIsNull()
    {
        // Arrange
        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("user_agreement"))
            .ReturnsAsync((string?)null);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var result = service.GetAgreementAsync().GetAwaiter().GetResult();

        // Assert: 即使配置值为空，也应返回非空 DTO
        Assert.NotNull(result);
        Assert.NotNull(result.Content);
        Assert.Equal(string.Empty, result.Content);
    }

    /// <summary>
    /// Property 8: GetAgreementAsync 返回非空 DTO，即使配置值为空字符串
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.1, 16.1, 16.2, 16.3**
    /// </summary>
    [Fact]
    public void GetAgreementAsync_ReturnsNonNullDto_WhenConfigValueIsEmpty()
    {
        // Arrange
        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("user_agreement"))
            .ReturnsAsync(string.Empty);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var result = service.GetAgreementAsync().GetAwaiter().GetResult();

        // Assert
        Assert.NotNull(result);
        Assert.NotNull(result.Content);
        Assert.Equal(string.Empty, result.Content);
    }

    /// <summary>
    /// Property 8: GetAgreementAsync 响应格式一致性 - Content 属性始终存在
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.1, 16.1, 16.2, 16.3**
    /// </summary>
    [Property(MaxTest = 100)]
    public bool GetAgreementAsync_ContentPropertyAlwaysExists(PositiveInt seed)
    {
        // Arrange: 使用不同的配置值
        var configValues = new string?[] { null, "", "协议内容", "用户协议\n第一条...", $"Agreement_{seed.Get}" };
        var configValue = configValues[seed.Get % configValues.Length];

        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("user_agreement"))
            .ReturnsAsync(configValue);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var result = service.GetAgreementAsync().GetAwaiter().GetResult();

        // Assert: Content 属性始终存在且不为 null
        return result != null && result.Content != null;
    }

    #endregion

    #region Property 8: 响应格式一致性 - GetPrivacyAsync

    /// <summary>
    /// Property 8: GetPrivacyAsync 返回包含 Content 属性的 PrivacyDto
    /// *For any* GetPrivacyAsync call, the returned PrivacyDto SHALL have a Content property.
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.2, 16.1, 16.2, 16.3**
    /// </summary>
    [Property(MaxTest = 100)]
    public bool GetPrivacyAsync_ReturnsPrivacyDtoWithContentProperty(NonEmptyString content)
    {
        // Arrange
        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("privacy_policy"))
            .ReturnsAsync(content.Get);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var result = service.GetPrivacyAsync().GetAwaiter().GetResult();

        // Assert: 验证返回的 PrivacyDto 包含 Content 属性且值正确
        return result != null && result.Content == content.Get;
    }

    /// <summary>
    /// Property 8: GetPrivacyAsync 返回非空 DTO，即使配置值为空
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.2, 16.1, 16.2, 16.3**
    /// </summary>
    [Fact]
    public void GetPrivacyAsync_ReturnsNonNullDto_WhenConfigValueIsNull()
    {
        // Arrange
        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("privacy_policy"))
            .ReturnsAsync((string?)null);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var result = service.GetPrivacyAsync().GetAwaiter().GetResult();

        // Assert: 即使配置值为空，也应返回非空 DTO
        Assert.NotNull(result);
        Assert.NotNull(result.Content);
        Assert.Equal(string.Empty, result.Content);
    }

    /// <summary>
    /// Property 8: GetPrivacyAsync 返回非空 DTO，即使配置值为空字符串
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.2, 16.1, 16.2, 16.3**
    /// </summary>
    [Fact]
    public void GetPrivacyAsync_ReturnsNonNullDto_WhenConfigValueIsEmpty()
    {
        // Arrange
        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("privacy_policy"))
            .ReturnsAsync(string.Empty);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var result = service.GetPrivacyAsync().GetAwaiter().GetResult();

        // Assert
        Assert.NotNull(result);
        Assert.NotNull(result.Content);
        Assert.Equal(string.Empty, result.Content);
    }

    /// <summary>
    /// Property 8: GetPrivacyAsync 响应格式一致性 - Content 属性始终存在
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.2, 16.1, 16.2, 16.3**
    /// </summary>
    [Property(MaxTest = 100)]
    public bool GetPrivacyAsync_ContentPropertyAlwaysExists(PositiveInt seed)
    {
        // Arrange: 使用不同的配置值
        var configValues = new string?[] { null, "", "隐私政策", "隐私政策\n第一条...", $"Privacy_{seed.Get}" };
        var configValue = configValues[seed.Get % configValues.Length];

        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("privacy_policy"))
            .ReturnsAsync(configValue);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var result = service.GetPrivacyAsync().GetAwaiter().GetResult();

        // Assert: Content 属性始终存在且不为 null
        return result != null && result.Content != null;
    }

    #endregion

    #region Property 8: 响应格式一致性 - GetAboutAsync

    /// <summary>
    /// Property 8: GetAboutAsync 返回包含 Content 和 Version 属性的 AboutDto
    /// *For any* GetAboutAsync call, the returned AboutDto SHALL have Content and Version properties.
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.3, 16.1, 16.2, 16.3**
    /// </summary>
    [Property(MaxTest = 100)]
    public bool GetAboutAsync_ReturnsAboutDtoWithContentAndVersionProperties(NonEmptyString content, NonEmptyString version)
    {
        // Arrange
        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("about_us"))
            .ReturnsAsync(content.Get);
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("app_version"))
            .ReturnsAsync(version.Get);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var result = service.GetAboutAsync().GetAwaiter().GetResult();

        // Assert: 验证返回的 AboutDto 包含 Content 和 Version 属性且值正确
        return result != null && 
               result.Content == content.Get && 
               result.Version == version.Get;
    }

    /// <summary>
    /// Property 8: GetAboutAsync 返回非空 DTO，即使配置值为空
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.3, 16.1, 16.2, 16.3**
    /// </summary>
    [Fact]
    public void GetAboutAsync_ReturnsNonNullDto_WhenConfigValuesAreNull()
    {
        // Arrange
        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("about_us"))
            .ReturnsAsync((string?)null);
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("app_version"))
            .ReturnsAsync((string?)null);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var result = service.GetAboutAsync().GetAwaiter().GetResult();

        // Assert: 即使配置值为空，也应返回非空 DTO
        Assert.NotNull(result);
        Assert.NotNull(result.Content);
        Assert.NotNull(result.Version);
        Assert.Equal(string.Empty, result.Content);
    }

    /// <summary>
    /// Property 8: GetAboutAsync Version 有默认值，当未配置时
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.3, 16.1, 16.2, 16.3**
    /// </summary>
    [Fact]
    public void GetAboutAsync_VersionHasDefaultValue_WhenNotConfigured()
    {
        // Arrange
        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("about_us"))
            .ReturnsAsync("关于我们内容");
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("app_version"))
            .ReturnsAsync((string?)null);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var result = service.GetAboutAsync().GetAwaiter().GetResult();

        // Assert: Version 应该有默认值 "1.0.0"
        Assert.NotNull(result);
        Assert.Equal("1.0.0", result.Version);
    }

    /// <summary>
    /// Property 8: GetAboutAsync Version 有默认值，当配置为空字符串时
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.3, 16.1, 16.2, 16.3**
    /// </summary>
    [Fact]
    public void GetAboutAsync_VersionHasDefaultValue_WhenConfiguredAsEmpty()
    {
        // Arrange
        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("about_us"))
            .ReturnsAsync("关于我们内容");
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("app_version"))
            .ReturnsAsync(string.Empty);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var result = service.GetAboutAsync().GetAwaiter().GetResult();

        // Assert: 当配置为空字符串时，应该返回空字符串（不是默认值）
        // 因为 SystemService 只在 null 时使用默认值
        Assert.NotNull(result);
        Assert.Equal(string.Empty, result.Version);
    }

    /// <summary>
    /// Property 8: GetAboutAsync 响应格式一致性 - Content 和 Version 属性始终存在
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.3, 16.1, 16.2, 16.3**
    /// </summary>
    [Property(MaxTest = 100)]
    public bool GetAboutAsync_ContentAndVersionPropertiesAlwaysExist(PositiveInt seed)
    {
        // Arrange: 使用不同的配置值组合
        var contentValues = new string?[] { null, "", "关于我们", "公司介绍\n...", $"About_{seed.Get}" };
        var versionValues = new string?[] { null, "", "1.0.0", "2.1.3", $"v{seed.Get % 10}.{seed.Get % 100}.{seed.Get % 1000}" };
        
        var contentValue = contentValues[seed.Get % contentValues.Length];
        var versionValue = versionValues[(seed.Get / contentValues.Length) % versionValues.Length];

        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("about_us"))
            .ReturnsAsync(contentValue);
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("app_version"))
            .ReturnsAsync(versionValue);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var result = service.GetAboutAsync().GetAwaiter().GetResult();

        // Assert: Content 和 Version 属性始终存在且不为 null
        return result != null && result.Content != null && result.Version != null;
    }

    #endregion

    #region 综合属性测试

    /// <summary>
    /// Property 8: 所有系统配置方法返回非空 DTO
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.1, 14.2, 14.3, 16.1, 16.2, 16.3**
    /// </summary>
    [Property(MaxTest = 100)]
    public bool AllSystemMethods_ReturnNonNullDtos(PositiveInt seed)
    {
        // Arrange: 随机配置值
        var configValues = new string?[] { null, "", $"Content_{seed.Get}" };
        var agreementValue = configValues[seed.Get % configValues.Length];
        var privacyValue = configValues[(seed.Get + 1) % configValues.Length];
        var aboutValue = configValues[(seed.Get + 2) % configValues.Length];
        var versionValue = configValues[(seed.Get + 3) % configValues.Length];

        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("user_agreement"))
            .ReturnsAsync(agreementValue);
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("privacy_policy"))
            .ReturnsAsync(privacyValue);
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("about_us"))
            .ReturnsAsync(aboutValue);
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("app_version"))
            .ReturnsAsync(versionValue);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var agreement = service.GetAgreementAsync().GetAwaiter().GetResult();
        var privacy = service.GetPrivacyAsync().GetAwaiter().GetResult();
        var about = service.GetAboutAsync().GetAwaiter().GetResult();

        // Assert: 所有方法都返回非空 DTO
        return agreement != null && privacy != null && about != null;
    }

    /// <summary>
    /// Property 8: 所有系统配置方法的响应属性不为 null
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.1, 14.2, 14.3, 16.1, 16.2, 16.3**
    /// </summary>
    [Property(MaxTest = 100)]
    public bool AllSystemMethods_ResponsePropertiesAreNotNull(PositiveInt seed)
    {
        // Arrange: 随机配置值
        var configValues = new string?[] { null, "", $"Content_{seed.Get}" };
        var agreementValue = configValues[seed.Get % configValues.Length];
        var privacyValue = configValues[(seed.Get + 1) % configValues.Length];
        var aboutValue = configValues[(seed.Get + 2) % configValues.Length];
        var versionValue = configValues[(seed.Get + 3) % configValues.Length];

        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("user_agreement"))
            .ReturnsAsync(agreementValue);
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("privacy_policy"))
            .ReturnsAsync(privacyValue);
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("about_us"))
            .ReturnsAsync(aboutValue);
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("app_version"))
            .ReturnsAsync(versionValue);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var agreement = service.GetAgreementAsync().GetAwaiter().GetResult();
        var privacy = service.GetPrivacyAsync().GetAwaiter().GetResult();
        var about = service.GetAboutAsync().GetAwaiter().GetResult();

        // Assert: 所有响应属性都不为 null
        return agreement.Content != null && 
               privacy.Content != null && 
               about.Content != null && 
               about.Version != null;
    }

    /// <summary>
    /// Property 8: 配置值正确传递到响应中
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.1, 14.2, 14.3, 16.1, 16.2, 16.3**
    /// </summary>
    [Property(MaxTest = 100)]
    public bool ConfigValues_CorrectlyPassedToResponse(NonEmptyString agreementContent, NonEmptyString privacyContent, NonEmptyString aboutContent, NonEmptyString version)
    {
        // Arrange
        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("user_agreement"))
            .ReturnsAsync(agreementContent.Get);
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("privacy_policy"))
            .ReturnsAsync(privacyContent.Get);
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("about_us"))
            .ReturnsAsync(aboutContent.Get);
        mockConfigService
            .Setup(x => x.GetConfigValueAsync("app_version"))
            .ReturnsAsync(version.Get);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var agreement = service.GetAgreementAsync().GetAwaiter().GetResult();
        var privacy = service.GetPrivacyAsync().GetAwaiter().GetResult();
        var about = service.GetAboutAsync().GetAwaiter().GetResult();

        // Assert: 配置值正确传递到响应中
        return agreement.Content == agreementContent.Get &&
               privacy.Content == privacyContent.Get &&
               about.Content == aboutContent.Get &&
               about.Version == version.Get;
    }

    /// <summary>
    /// Property 8: 空配置值时使用默认值或空字符串
    /// 
    /// **Feature: miniapp-api, Property 8: 响应格式一致性**
    /// **Validates: Requirements 14.1, 14.2, 14.3, 16.1, 16.2, 16.3**
    /// </summary>
    [Fact]
    public void NullConfigValues_UseDefaultOrEmptyString()
    {
        // Arrange
        var mockConfigService = new Mock<IConfigService>();
        mockConfigService
            .Setup(x => x.GetConfigValueAsync(It.IsAny<string>()))
            .ReturnsAsync((string?)null);

        var service = new SystemService(mockConfigService.Object, _mockLogger.Object);

        // Act
        var agreement = service.GetAgreementAsync().GetAwaiter().GetResult();
        var privacy = service.GetPrivacyAsync().GetAwaiter().GetResult();
        var about = service.GetAboutAsync().GetAwaiter().GetResult();

        // Assert
        Assert.Equal(string.Empty, agreement.Content);
        Assert.Equal(string.Empty, privacy.Content);
        Assert.Equal(string.Empty, about.Content);
        Assert.Equal("1.0.0", about.Version); // Version 有默认值
    }

    #endregion
}