using BuildFlow.Platform.Application.Permissions.Commands;
using BuildFlow.Platform.Application.Permissions.DTOs;
using BuildFlow.Platform.Application.Permissions.Handlers;
using BuildFlow.Platform.Application.Permissions.Queries;
using BuildFlow.Platform.Domain.Entities;
using BuildFlow.Platform.Infrastructure.Persistence;
using BuildFlow.Shared.Domain.Exceptions;
using FluentAssertions;
using Microsoft.EntityFrameworkCore;
using Xunit;

namespace BuildFlow.Platform.Tests.Permissions;

/// <summary>
/// [SOP-PLATFORM] 权限管理全 Handler 覆盖测试。
/// 覆盖:Create / Update / Delete / GetList / GetById / GetTree。
/// 飞书矩阵: platform/Permissions 子域(6 Handler 零覆盖→全补)
/// </summary>
public class PermissionHandlerTests
{
    private static PlatformDbContext CreateDb([System.Runtime.CompilerServices.CallerMemberName] string name = "")
        => PlatformTestDb.CreateDbContext(name);

    private static Permission NewPermission(string code, string? group = "TestGroup")
        => PlatformTestDb.WithAudit(new Permission
        {
            Name = $"权限_{code}",
            Code = code,
            Description = "desc",
            Group = group
        });

    [Fact]
    public async Task Create_Valid_ReturnsDto()
    {
        var db = CreateDb();
        var handler = new CreatePermissionCommandHandler(db);

        var result = await handler.Handle(
            new CreatePermissionCommand("创建用户", "user:create", "描述", "UserManagement"),
            CancellationToken.None);

        result.Code.Should().Be("user:create");
        result.Name.Should().Be("创建用户");
        (await db.Permissions.CountAsync()).Should().Be(1);
    }

    [Fact]
    public async Task Create_DuplicateCode_ThrowsBusiness()
    {
        var db = CreateDb();
        db.Permissions.Add(NewPermission("user:create"));
        await db.SaveChangesAsync();
        var handler = new CreatePermissionCommandHandler(db);

        var act = async () => await handler.Handle(
            new CreatePermissionCommand("重复", "user:create", null, null), CancellationToken.None);

        await act.Should().ThrowAsync<BusinessException>("Code 唯一,重复应拒绝");
    }

    [Fact]
    public async Task Update_Existing_OverwritesNullableFields()
    {
        var db = CreateDb();
        var p = NewPermission("user:read");
        db.Permissions.Add(p);
        await db.SaveChangesAsync();
        var handler = new UpdatePermissionCommandHandler(db);

        var result = await handler.Handle(
            new UpdatePermissionCommand(p.Id, "新名称", "新描述", "NewGroup"), CancellationToken.None);

        result.Name.Should().Be("新名称");
        result.Description.Should().Be("新描述");
        result.Group.Should().Be("NewGroup");
        result.Code.Should().Be("user:read", "Code 不可改");
    }

    [Fact]
    public async Task Update_NonExistent_ThrowsNotFound()
    {
        var db = CreateDb();
        var handler = new UpdatePermissionCommandHandler(db);

        var act = async () => await handler.Handle(
            new UpdatePermissionCommand(Guid.NewGuid(), "x", null, null), CancellationToken.None);

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

    [Fact]
    public async Task Delete_Existing_RemovesAndUnlinksRoles()
    {
        var db = CreateDb();
        var p = NewPermission("user:delete");
        var role = PlatformTestDb.WithAudit(new Role { Name = "Admin" });
        var link = new RolePermission { Role = role, Permission = p };
        db.Permissions.Add(p);
        db.Roles.Add(role);
        db.RolePermissions.Add(link);
        await db.SaveChangesAsync();
        var handler = new DeletePermissionCommandHandler(db);

        await handler.Handle(new DeletePermissionCommand(p.Id), CancellationToken.None);

        (await db.Permissions.AnyAsync(x => x.Id == p.Id)).Should().BeFalse("软删后不可见");
    }

    [Fact]
    public async Task Delete_NonExistent_ThrowsNotFound()
    {
        var db = CreateDb();
        var handler = new DeletePermissionCommandHandler(db);

        var act = async () => await handler.Handle(new DeletePermissionCommand(Guid.NewGuid()), CancellationToken.None);

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

    [Fact]
    public async Task GetList_ReturnsAll()
    {
        var db = CreateDb();
        db.Permissions.AddRange(NewPermission("p1"), NewPermission("p2"));
        await db.SaveChangesAsync();
        var handler = new GetPermissionListQueryHandler(db);

        var result = await handler.Handle(new GetPermissionListQuery(), CancellationToken.None);

        result.Should().HaveCount(2);
    }

    [Fact]
    public async Task GetById_Existing_ReturnsDto()
    {
        var db = CreateDb();
        var p = NewPermission("user:read");
        db.Permissions.Add(p);
        await db.SaveChangesAsync();
        var handler = new GetPermissionByIdQueryHandler(db);

        var result = await handler.Handle(new GetPermissionByIdQuery(p.Id), CancellationToken.None);

        result.Code.Should().Be("user:read");
    }

    [Fact]
    public async Task GetById_NonExistent_ThrowsNotFound()
    {
        var db = CreateDb();
        var handler = new GetPermissionByIdQueryHandler(db);

        var act = async () => await handler.Handle(new GetPermissionByIdQuery(Guid.NewGuid()), CancellationToken.None);

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

    [Fact]
    public async Task GetTree_GroupsByGroupField()
    {
        var db = CreateDb();
        db.Permissions.AddRange(
            NewPermission("a:1", "GroupA"),
            NewPermission("a:2", "GroupA"),
            NewPermission("b:1", "GroupB"));
        await db.SaveChangesAsync();
        var handler = new GetPermissionTreeQueryHandler(db);

        var tree = await handler.Handle(new GetPermissionTreeQuery(), CancellationToken.None);

        tree.Should().HaveCount(2);
        tree.First(g => g.Group == "GroupA").Permissions.Should().HaveCount(2);
        tree.First(g => g.Group == "GroupB").Permissions.Should().HaveCount(1);
    }

    [Fact]
    public async Task GetTree_NullGroup_GoesToUngrouped()
    {
        var db = CreateDb();
        db.Permissions.Add(NewPermission("no:group", null));
        await db.SaveChangesAsync();
        var handler = new GetPermissionTreeQueryHandler(db);

        var tree = await handler.Handle(new GetPermissionTreeQuery(), CancellationToken.None);

        tree.Should().ContainSingle();
        tree[0].Group.Should().Be("未分组");
    }
}