/******************************************************************************
 * Copyright (C) Ultraleap, Inc. 2011-2021.                                   *
 *                                                                            *
 * Use subject to the terms of the Apache License 2.0 available at            *
 * http://www.apache.org/licenses/LICENSE-2.0, or another agreement           *
 * between Ultraleap and you, your company or other organization.             *
 ******************************************************************************/

using Leap;
using Leap.Unity.Attributes;
using Leap.Unity.Space;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

namespace Leap.Unity.Interaction
{

    /// <summary>
    /// IInteractionBehaviour is the interface that defines all Interaction objects,
    /// specifying the minimum set of functionality required to make objects interactable.
    /// </summary>
    public interface IInteractionBehaviour /* : IInternalInteractionBehaviour */
    {

        // Properties from MonoBehaviour.
        string name { get; } // (subclass MonoBehaviour to satisfy)
        GameObject gameObject { get; } // ^
        Transform transform { get; } // ^

        // Properties for interaction.
        InteractionManager manager { get; }
        Rigidbody rigidbody { get; }
        ISpaceComponent space { get; } // OK to return null if this object is not in
                                       // curved space.

        // Interaction overrides.
        IgnoreHoverMode ignoreHoverMode { get; }
        bool ignorePrimaryHover { get; }
        bool ignoreContact { get; }
        IgnoreHoverMode ignoreGraspingMode { get; }
        bool ignoreGrasping { get; }

        // Interaction settings.
        bool allowMultiGrasp { get; }

        // Interaction layers.
        SingleLayer interactionLayer { get; }
        SingleLayer noContactLayer { get; }

        // Called by the Interaction Manager manually
        // every fixed (physics) frame.
        void FixedUpdateObject();

        // Interaction types:
        // - Hover
        //   -- Primary Hover
        // - Contact
        // - Grasping
        //   -- Suspension

        // Hover
        float GetHoverDistance(Vector3 worldPosition);
        void BeginHover(List<InteractionController> beganHovering);
        void EndHover(List<InteractionController> endedHovering);
        void StayHovered(List<InteractionController> currentlyHovering);

        // Primary hover
        void BeginPrimaryHover(List<InteractionController> beganPrimaryHovering);
        void EndPrimaryHover(List<InteractionController> endedPrimaryHovering);
        void StayPrimaryHovered(List<InteractionController> currentlyPrimaryHovering);

        // Contact
        void BeginContact(List<InteractionController> beganContact);
        void EndContact(List<InteractionController> endedContact);
        void StayContacted(List<InteractionController> currentlyContacting);

        // Grasping
        bool isGrasped { get; }
        void BeginGrasp(List<InteractionController> beganGrasping);
        void EndGrasp(List<InteractionController> endedGrasping);
        void StayGrasped(List<InteractionController> currentlyGrasping);

        // Suspension
        bool isSuspended { get; }
        void BeginSuspension(InteractionController beganSuspending);
        void EndSuspension(InteractionController endedSuspending);

    }

}