using LehrerApp.Sync.Models;

namespace LehrerApp.Api;

public class PlainEventStore(EventStore eventStore)
{
    // Grade/ExamResult bewusst NICHT erlaubt: PlainSyncEvent.Payload ist Klartext-JSON (siehe
    // SyncModels.cs), beide Typen tragen aber eine StudentId plus Notenwert/-kommentar -
    // personenbezogene Daten dürfen laut TODO.md 10.3.3 nicht unverschlüsselt übertragen werden.
    private static readonly HashSet<string> Allowed = ["WorkTask", "Lesson"];

    public PlainPushResponse Push(string userId, List<PlainSyncEvent> events)
    {
        var permitted = events.Where(e => Allowed.Contains(e.EntityType)).ToList();
        var rejected  = events.Where(e => !Allowed.Contains(e.EntityType))
                              .Select(e => e.EventId).ToList();
        if (permitted.Count == 0) return new() { Success = true, RejectedEventIds = rejected };

        var syncEvents = permitted.Select(e => new SyncEvent
        {
            EventId = e.EventId, DeviceId = e.DeviceId,
            DeviceType = DeviceType.Companion,
            Timestamp = e.Timestamp, SequenceNr = 0,
            EntityType = e.EntityType, EntityId = e.EntityId,
            Operation = e.Operation, Payload = e.Payload,
        }).ToList();

        var result = eventStore.Push(userId, syncEvents);
        return new()
        {
            Success          = result.Success,
            ServerSequenceNr = result.ServerSequenceNr,
            RejectedEventIds = [.. result.ConflictingEventIds, .. rejected],
        };
    }
}