using BuildFlow.Shared.Domain.Errors;
using BuildFlow.Shared.Domain.Exceptions;
using FluentAssertions;
using IM.Application.Chat.Commands;
using IM.Application.Chat.Handlers;
using IM.Infrastructure.Persistence;
using Microsoft.EntityFrameworkCore;
using Xunit;

namespace BuildFlow.IM.Tests.Chat;

/// <summary>
/// RemoveGroupMemberCommandHandler：群不存在 NotFound；管理员移除群主 Business；
/// 普通成员自助退群成功（同步移出会话参与者）。
/// </summary>
public class RemoveGroupMemberCommandHandlerTests
{
    private static readonly Guid OwnerId = Guid.Parse("22222222-2222-2222-2222-222222222222");
    private static readonly Guid MemberId = Guid.Parse("33333333-3333-3333-3333-333333333333");
    private static readonly Guid AdminId = Guid.Parse("30000000-0000-0000-0000-000000000001");
    private const string Name = "group-1";

    [Fact]
    public async Task Throws_not_found_when_group_missing()
    {
        await using var db = IMTestDb.Create();
        var handler = new RemoveGroupMemberCommandHandler(db);
        var act = async () => await handler.Handle(new RemoveGroupMemberCommand(Guid.NewGuid(), OwnerId, MemberId), CancellationToken.None);

        var ex = await act.Should().ThrowAsync<NotFoundException>();
        ex.Which.Code.Should().Be(ErrorCode.NotFound);
    }

    [Fact]
    public async Task Admin_cannot_remove_owner()
    {
        await using var db = IMTestDb.Create();
        var (_, groupId) = await IMTestDb.SeedGroupAsync(db, Name, OwnerId, AdminId);
        var handler = new RemoveGroupMemberCommandHandler(db);
        var act = async () => await handler.Handle(new RemoveGroupMemberCommand(groupId, AdminId, OwnerId), CancellationToken.None);

        var ex = await act.Should().ThrowAsync<BusinessException>();
        ex.Which.Code.Should().Be(ErrorCode.Business);
    }

    [Fact]
    public async Task Member_can_remove_self()
    {
        await using var db = IMTestDb.Create();
        var (convId, groupId) = await IMTestDb.SeedGroupAsync(db, Name, OwnerId, MemberId);
        var handler = new RemoveGroupMemberCommandHandler(db);
        await handler.Handle(new RemoveGroupMemberCommand(groupId, MemberId, MemberId), CancellationToken.None);

        (await db.GroupMembers.AnyAsync(m => m.GroupId == groupId && m.UserId == MemberId)).Should().BeFalse();
        (await db.ConversationParticipants.AnyAsync(p => p.ConversationId == convId && p.UserId == MemberId)).Should().BeFalse();
    }
}