using System.Diagnostics.CodeAnalysis;

namespace NeonSprawl.Server.Game.Npc;

/// <summary>
/// Session in-memory aggro holder store keyed by prototype NPC instance id (NEO-92).
/// HTTP projection lands in NEO-94; NEO-93 reads holder for behavior state transitions.
/// </summary>
public interface IThreatStateStore
{
    /// <summary>Reads threat for a known prototype NPC instance. Lazy-initializes an empty holder row.</summary>
    bool TryGet(string? npcInstanceId, [NotNullWhen(true)] out ThreatStateSnapshot snapshot);

    /// <summary>Sets or clears the aggro holder for a known prototype NPC instance.</summary>
    bool TrySetHolder(string? npcInstanceId, string? playerIdLowercaseOrNull);

    /// <summary>Clears the aggro holder for a known prototype NPC instance.</summary>
    bool TryClearHolder(string? npcInstanceId);
}