namespace UnityEngine.AdaptivePerformance.Samsung.Android
{
    /// <summary>
    /// Event handler declaration.
    /// </summary>
    public delegate void VariableRefreshRateEventHandler();

    /// <summary>
    /// Interface of the Samsung Variable Refresh Rate API.
    /// </summary>
    public interface IVariableRefreshRate
    {
        /// <summary>
        /// List of supported display refresh rates.
        /// </summary>
        int[] SupportedRefreshRates { get; }

        /// <summary>
        /// The current display refresh rate.
        /// </summary>
        int CurrentRefreshRate { get; }

        /// <summary>
        /// Change the current display refresh rate to the value referenced by the given index from the list of supported refresh rates.
        /// </summary>
        /// <param name="index"></param>
        /// <returns>True if the display refresh rate was updated successfully, false otherwise. Returns false if the requested refresh rate is larger than the `Application.targetFrameRate`. **Note:** There is a delay before the actual refresh rate and the value of `Screen.currentResolution.refreshRate` are updated.</returns>
        bool SetRefreshRateByIndex(int index);

        /// <summary>
        /// Event that is called if the current display refresh rate or the list of supported refresh rate is changed externally, for example by changing display settings.
        /// </summary>
        event VariableRefreshRateEventHandler RefreshRateChanged;
    }

    /// <summary>
    /// Holds the global instance to the Variable Refresh Rate API.
    /// </summary>
    public static class VariableRefreshRate
    {
        /// <summary>
        /// Global instance to access the variable refresh API.
        /// Can be null if variable refresh rate is not supported.
        /// </summary>
        static public IVariableRefreshRate Instance { get; set; }
    }
}