using BuildFlow.Shared.Domain.Errors;
using BuildFlow.Shared.Domain.Exceptions;
using FluentAssertions;
using Microsoft.EntityFrameworkCore;
using Monitoring.Application.ExternalSystems.Commands;
using Monitoring.Application.ExternalSystems.DTOs;
using Monitoring.Application.ExternalSystems.Handlers;
using Monitoring.Application.ExternalSystems.Queries;
using Monitoring.Infrastructure.Persistence;

namespace BuildFlow.Monitoring.Tests;

/// <summary>
/// [SOP-MONITORING] ExternalSystems 子域 Handler 全覆盖测试。
/// 覆盖: Create / List / GetDetail / Update（含无效类型、缺失、非法 JSON、凭证覆盖分支）。
/// 约定: 直接用 new Handler(db) 调 Handle；db 由 MonitoringTestDb.Create 提供（自动补审计字段）。
/// 用 Create handler 串联构造前置数据，避免直接依赖实体内部构造。
/// </summary>
public class ExternalSystemsHandlerTests
{
    private static MonitoringDbContext Db([System.Runtime.CompilerServices.CallerMemberName] string name = "")
        => MonitoringTestDb.Create(name);

    #region Create

    [Fact]
    public async Task Create_Valid_ReturnsDtoAndPersists()
    {
        await using var db = Db();
        var result = await new CreateExternalSystemCommandHandler(db).Handle(
            new CreateExternalSystemCommand("u号租", 1, "https://api.example.com", 300, null),
            CancellationToken.None);

        result.Should().NotBeNull();
        result.Name.Should().Be("u号租");
        result.SystemType.Should().Be(1);
        result.BaseUrl.Should().Be("https://api.example.com");
        result.IsEnabled.Should().BeTrue();
        result.PollIntervalSeconds.Should().Be(300);
        (await db.ExternalSystems.CountAsync()).Should().Be(1);
    }

    [Fact]
    public async Task Create_InvalidSystemType_ThrowsBusiness()
    {
        await using var db = Db();
        var act = async () => await new CreateExternalSystemCommandHandler(db).Handle(
            new CreateExternalSystemCommand("x", 999, "https://x", 0, null),
            CancellationToken.None);
        var ex = await act.Should().ThrowAsync<BusinessException>();
        ex.Which.Code.Should().Be(ErrorCode.InvalidParam);
    }

    #endregion

    #region List

    [Fact]
    public async Task List_Empty_ReturnsEmpty()
    {
        await using var db = Db();
        var result = await new ListExternalSystemsQueryHandler(db)
            .Handle(new ListExternalSystemsQuery(), CancellationToken.None);
        result.Should().BeEmpty();
    }

    [Fact]
    public async Task List_ReturnsAllDescendingByCreatedAt()
    {
        await using var db = Db();
        var create = new CreateExternalSystemCommandHandler(db);
        var a = await create.Handle(new CreateExternalSystemCommand("A", 1, "https://a", 1, null), CancellationToken.None);
        var b = await create.Handle(new CreateExternalSystemCommand("B", 1, "https://b", 1, null), CancellationToken.None);

        // 强制 A 更早创建，使倒序断言稳定
        var entA = await db.ExternalSystems.FirstAsync(x => x.Id == a.Id);
        entA.CreatedAt = DateTime.UtcNow.AddMinutes(-10);
        await db.SaveChangesAsync();

        var list = await new ListExternalSystemsQueryHandler(db)
            .Handle(new ListExternalSystemsQuery(), CancellationToken.None);
        list.Should().HaveCount(2);
        list[0].Name.Should().Be("B");
        list[1].Name.Should().Be("A");
    }

    #endregion

    #region GetDetail

    [Fact]
    public async Task GetDetail_Existing_ReturnsDetail()
    {
        await using var db = Db();
        var created = await new CreateExternalSystemCommandHandler(db).Handle(
            new CreateExternalSystemCommand("u号租", 1, "https://x", 60, null),
            CancellationToken.None);

        var detail = await new GetExternalSystemDetailQueryHandler(db)
            .Handle(new GetExternalSystemDetailQuery(created.Id), CancellationToken.None);
        detail.Should().NotBeNull();
        detail.Id.Should().Be(created.Id);
        detail.Name.Should().Be("u号租");
    }

    [Fact]
    public async Task GetDetail_NotFound_Throws()
    {
        await using var db = Db();
        var act = async () => await new GetExternalSystemDetailQueryHandler(db)
            .Handle(new GetExternalSystemDetailQuery(Guid.NewGuid()), CancellationToken.None);
        var ex = await act.Should().ThrowAsync<NotFoundException>();
        ex.Which.Code.Should().Be(ErrorCode.NotFound);
    }

    #endregion

    #region Update

    [Fact]
    public async Task Update_NameAndBaseUrl_Overwrites()
    {
        await using var db = Db();
        var created = await new CreateExternalSystemCommandHandler(db).Handle(
            new CreateExternalSystemCommand("old", 1, "https://old", 60, null),
            CancellationToken.None);
        var result = await new UpdateExternalSystemCommandHandler(db).Handle(
            new UpdateExternalSystemCommand(created.Id, "new", "https://new", null, null, null, null),
            CancellationToken.None);
        result.Name.Should().Be("new");
        result.BaseUrl.Should().Be("https://new");
    }

    [Fact]
    public async Task Update_NonExistent_ThrowsNotFound()
    {
        await using var db = Db();
        var act = async () => await new UpdateExternalSystemCommandHandler(db).Handle(
            new UpdateExternalSystemCommand(Guid.NewGuid(), "x", null, null, null, null, null),
            CancellationToken.None);
        var ex = await act.Should().ThrowAsync<NotFoundException>();
        ex.Which.Code.Should().Be(ErrorCode.NotFound);
    }

    [Fact]
    public async Task Update_InvalidParametersJson_ThrowsBusiness()
    {
        await using var db = Db();
        var created = await new CreateExternalSystemCommandHandler(db).Handle(
            new CreateExternalSystemCommand("x", 1, "https://x", 60, null),
            CancellationToken.None);
        var act = async () => await new UpdateExternalSystemCommandHandler(db).Handle(
            new UpdateExternalSystemCommand(created.Id, null, null, null, null, "{bad json", null),
            CancellationToken.None);
        var ex = await act.Should().ThrowAsync<BusinessException>();
        ex.Which.Code.Should().Be(ErrorCode.InvalidParam);
    }

    [Fact]
    public async Task Update_Credentials_Overwrites()
    {
        await using var db = Db();
        var created = await new CreateExternalSystemCommandHandler(db).Handle(
            new CreateExternalSystemCommand("x", 1, "https://x", 60, null),
            CancellationToken.None);
        var creds = new List<CredentialInput> { new("token", "ak", "av", true, null) };
        await new UpdateExternalSystemCommandHandler(db).Handle(
            new UpdateExternalSystemCommand(created.Id, null, null, null, null, null, creds),
            CancellationToken.None);

        var detail = await new GetExternalSystemDetailQueryHandler(db)
            .Handle(new GetExternalSystemDetailQuery(created.Id), CancellationToken.None);
        detail.Credentials.Should().HaveCount(1);
        detail.Credentials[0].Key.Should().Be("ak");
    }

    #endregion
}