using System;
using Chernobyl.Mathematics.Geometry;

namespace Chernobyl.Mathematics.Collision
{
    /// <summary>
    /// An interface for objects that can be collided against and whose 
    /// collision status can be retrieved through an event.
    /// </summary>
    public interface ICollidable : IShape
    {
        /// <summary>
        /// An event that is raised when a <see cref="ICollidable"/> has
        /// started colliding with this <see cref="ICollidable"/>. When the
        /// collision has ended, <see cref="OnCollisionEnded"/> will be invoked.
        /// </summary>
        event EventHandler OnCollisionStarted;

        /// <summary>
        /// An event that is raised when the collision with a
        /// <see cref="ICollidable"/> has ended. This will event will be raised
        /// after the invocation of <see cref="OnCollisionStarted"/>.
        /// </summary>
        event EventHandler OnCollisionEnded;

        /// <summary>
        /// Called when this <see cref="ICollidable"/> has started colliding
        /// with another <see cref="ICollidable"/>.
        /// </summary>
        /// <param name="collider">The object that was just hit.</param>
        void HandleCollisionStarted(ICollidable collider);

        /// <summary>
        /// Called when this <see cref="ICollidable"/> has stopped colliding
        /// with another <see cref="ICollidable"/>.
        /// </summary>
        /// <param name="collider">The object that was just hit.</param>
        void HandleCollisionEnded(ICollidable collider);
    }
}