using BuildFlow.Platform.Application.Users.DTOs;
using BuildFlow.Platform.Application.Users.Handlers;
using BuildFlow.Platform.Application.Users.Queries;
using File.Application.Features.Files.DTOs;
using File.Application.Features.Files.Queries;
using MediatR;
using NSubstitute;
using Xunit;

namespace BuildFlow.Platform.Tests.Users;

/// <summary>
/// 批量用户摘要查询测试。覆盖去重、缺失用户过滤、头像返回和空输入短路。
/// </summary>
public class GetUserSummariesQueryHandlerTests
{
    [Fact]
    public async Task Handle_ShouldReturnDistinctExistingUsersByGuid()
    {
        await using var db = PlatformTestDb.CreateDbContext();
        var aliceId = Guid.NewGuid();
        var bobId = Guid.NewGuid();
        var missingId = Guid.NewGuid();
        var alice = await PlatformTestDb.SeedUserAsync(db, aliceId, "alice");
        var bob = await PlatformTestDb.SeedUserAsync(db, bobId, "bob");
        alice.Avatar = "avatars/alice.png";
        bob.Avatar = null;
        await db.SaveChangesAsync();
        var mediator = Substitute.For<IMediator>();
        mediator.Send(Arg.Any<ResolveFilePreviewPathsQuery>(), Arg.Any<CancellationToken>())
            .Returns(Task.FromResult<IReadOnlyList<FilePreviewPathDto>>(
            [
                new("avatars/alice.png", "/api/files/preview?objectKey=avatars%2Falice.png")
            ]));
        var handler = new GetUserSummariesQueryHandler(db, mediator);

        var result = await handler.Handle(
            new GetUserSummariesQuery([aliceId, bobId, aliceId, missingId]),
            CancellationToken.None);

        Assert.Equal(2, result.Count);
        Assert.Equal(new UserSummaryDto(
            aliceId,
            "alice",
            "/api/files/preview?objectKey=avatars%2Falice.png"), result[aliceId]);
        Assert.Equal(new UserSummaryDto(bobId, "bob", null), result[bobId]);
        Assert.False(result.ContainsKey(missingId));
        await mediator.Received(1).Send(
            Arg.Is<ResolveFilePreviewPathsQuery>(query =>
                query.References.SequenceEqual(new string?[] { "avatars/alice.png" })),
            Arg.Any<CancellationToken>());
    }

    [Fact]
    public async Task Handle_EmptyIds_ShouldReturnEmptyResult()
    {
        await using var db = PlatformTestDb.CreateDbContext();
        var mediator = Substitute.For<IMediator>();
        var handler = new GetUserSummariesQueryHandler(db, mediator);

        var result = await handler.Handle(new GetUserSummariesQuery([]), CancellationToken.None);

        Assert.Empty(result);
        Assert.Empty(mediator.ReceivedCalls());
    }
}