using Grpc.Core;
using Mishima.Nexus.Wire.V1;

namespace Robotico.Nexus.Client.Tests.TestSupport;

/// <summary>
/// In-memory fake standing in for a real Nexus document engine host — the RPCs used by
/// <see cref="Robotico.Nexus.Client.Document.NexusDocumentClient"/> (Ping, CRUD, GetMany).
/// </summary>
public sealed class FakeDocumentEngineService : NexusDocumentEngineService.NexusDocumentEngineServiceBase
{
    private readonly Dictionary<(string Collection, string Id), string> _documents = [];

    /// <inheritdoc />
    public override Task<DocumentPingResponse> Ping(DocumentPingRequest request, ServerCallContext context)
    {
        NexusStatus? failure = FakeNexusTriggers.TryStatusFailure(context);
        return Task.FromResult(new DocumentPingResponse { Status = failure ?? NexusStatuses.Ok, EngineVersion = "fake" });
    }

    /// <inheritdoc />
    public override Task<DocumentUpsertResponse> UpsertDocument(DocumentUpsertRequest request, ServerCallContext context)
    {
        _documents[(request.CollectionName, request.DocumentId)] = request.JsonBody;
        return Task.FromResult(new DocumentUpsertResponse { Status = NexusStatuses.Ok });
    }

    /// <inheritdoc />
    public override Task<DocumentGetResponse> GetDocument(DocumentGetRequest request, ServerCallContext context)
    {
        if (_documents.TryGetValue((request.CollectionName, request.DocumentId), out string? body))
        {
            return Task.FromResult(new DocumentGetResponse { Status = NexusStatuses.Ok, Found = true, JsonBody = body });
        }

        return Task.FromResult(new DocumentGetResponse { Status = NexusStatuses.Ok, Found = false });
    }

    /// <inheritdoc />
    public override Task<DocumentCollectionGetManyResponse> CollectionGetMany(
        DocumentCollectionGetManyRequest request,
        ServerCallContext context)
    {
        DocumentCollectionGetManyResponse response = new() { Status = NexusStatuses.Ok };
        foreach (string id in request.DocumentIds)
        {
            if (!_documents.TryGetValue((request.CollectionName, id), out string? body))
            {
                continue;
            }

            response.Documents.Add(new DocumentCollectionDocumentWire
            {
                DocumentId = id,
                JsonBody = body,
            });
        }

        return Task.FromResult(response);
    }

    /// <inheritdoc />
    public override Task<DocumentDeleteResponse> DeleteDocument(DocumentDeleteRequest request, ServerCallContext context)
    {
        _documents.Remove((request.CollectionName, request.DocumentId));
        return Task.FromResult(new DocumentDeleteResponse { Status = NexusStatuses.Ok });
    }
}