using System.Collections.Generic;
using System;
using UnityEngine;

internal static class YieldInstructionCache
{
    class FloatComparer : IEqualityComparer<float>
    {
        bool IEqualityComparer<float>.Equals(float x, float y)
        {
            return x == y;
        }
        int IEqualityComparer<float>.GetHashCode(float obj)
        {
            return obj.GetHashCode();
        }
    }

    public static readonly WaitForEndOfFrame WaitForEndOfFrame = new WaitForEndOfFrame();
    public static readonly WaitForFixedUpdate WaitForFixedUpdate = new WaitForFixedUpdate();
    private static readonly Dictionary<float, WaitForSeconds> _timeInterval = new Dictionary<float, WaitForSeconds>(new FloatComparer());
    private static readonly Dictionary<Func<bool>, WaitUntil> _waitUntil = new Dictionary<Func<bool>, WaitUntil>();  // DG

    public static WaitForSeconds WaitForSeconds(float seconds)
    {
        WaitForSeconds wfs;
        if (!_timeInterval.TryGetValue(seconds, out wfs))
            _timeInterval.Add(seconds, wfs = new WaitForSeconds(seconds));
        return wfs;
    }

    // DG(20.05.08): parameter 없는 람다식 WaitUntil.
    public static WaitUntil WaitUntil(Func<bool> func)
    {
        WaitUntil wu;
        if (!_waitUntil.TryGetValue(func, out wu))
            _waitUntil.Add(func, wu = new WaitUntil(func));
        return wu;
    }
}