using System;

namespace Framework.Storage.Containers {

  /// <summary>Container providing access to persistent settings of the game</summary>
  /// <typeparam name="TState">Type of state stored in the container</typeparam>
  public interface IPersistentContainer<TState> where TState : class {

#if false
    /// <summary>Triggered when the settings should be reapplied</summary>
    /// <remarks>
    ///   <para>
    ///     Typically, you don't want to tightly integrate all your character controllers
    ///     and other game logic with the persistent state saving system and instead
    ///     create 'glue' objects which take the settings from a persistent container
    ///     and apply them at will.
    ///   </para>
    ///   <para>
    ///     This event can be used to signal to those 'glue' objects that they should
    ///     apply the current settings to the game's controllers again.
    ///   </para>
    ///   <para>
    ///     One danger of this event is that dead objects may keep hanging on to it.
    ///     Any 'glue' component needs to cleanly unsubscribe when it is being destroyed!
    ///   </para>
    /// </remarks>
    event Action Apply;
#endif   

    /// <summary>Accesses the informations stored in the state</summary>
    TState Access();

    /// <summary>Accesses the game-specific state</summary>
    /// <typeparam name="TSpecificState">
    ///   Game-specific type of state the game is storing 
    /// </typeparam>
    /// <returns>The game-specific state</returns>
    TSpecificState Access<TSpecificState>() where TSpecificState : TState;
    
    /// <summary>Loads the saved state of the container from disk</summary>
    void Load();

    /// <summary>Saves the current state of the container to disk</summary>
    void Save();

    /// <summary>Resets the container to its default settings</summary>
    void Reset();

  }

} // namespace Framework.Storage.Containers