using System.Collections.Generic;
using BaseGames.Core.Events;

namespace BaseGames.Core
{
    /// <summary>
    /// 可插件化的游戏状态行为接口。
    /// </summary>
    public interface IGameState
    {
        GameStateId Id { get; }

        /// <summary>合法的后继状态集合。GameStateMachine.TransitionTo() 据此校验。</summary>
        IReadOnlyCollection<GameStateId> ValidNextStates { get; }

        void OnEnter(GameStateId previousState);
        void OnExit(GameStateId nextState);

        /// <summary>每帧由 GameManager.Update() 调用（默认空实现）。</summary>
        void Tick(float deltaTime);
    }

}