using System;
using UnityEngine;
using UnityEngine.Video;

namespace OctoCore.Transitions
{
    /// <summary>
    /// Contract for a scene-transition visual effect (eyelid blink, plain fade, etc.).
    /// Lives inside the OctoCore package and has zero dependency on any concrete
    /// implementation or third-party tweening library. OctoNavigation only ever
    /// talks to this interface, never to a concrete type.
    /// </summary>
    public interface IOctoSceneTransition
    {
        /// <summary>True while a transition sequence is currently animating.</summary>
        bool IsBusy { get; }

        /// <summary>
        /// Assigns the visual content (clip/material) to use for the next CloseEyes() call.
        /// Pass a null clip for a plain transition with no video overlay.
        /// </summary>
        void SetClip(VideoClip clip, Material material);

        /// <summary>
        /// Enables or disables the eyelid/video layer swap for the next CloseEyes()/OpenEyes()
        /// sequence, if the implementation supports it. Implementations that don't support
        /// layer swapping can treat this as a no-op.
        /// </summary>
        void SetLayerSwapEnabled(bool enabled);

        /// <summary>Closes the transition over the given duration and invokes the callback on completion.</summary>
        void CloseEyes(float duration, Action onComplete);

        /// <summary>Opens the transition over the given duration and invokes the callback on completion.</summary>
        void OpenEyes(float duration, Action onComplete);

        /// <summary>Stops and hides any video overlay currently playing.</summary>
        void HideVideo();

        /// <summary>Reveals the video overlay after the given delay, if a clip is assigned.</summary>
        void ShowVideoAfterDelay(float delay);

        /// <summary>
        /// Hides the video overlay after the given delay. Lets a caller make the video
        /// disappear partway through the opening animation instead of only once it has
        /// fully finished.
        /// </summary>
        void HideVideoAfterDelay(float delay);
    }
}