using System;
using UnityEngine;

[Serializable]
public class RTlerp {
    public Vector2 sizeDelta_from;
    public Vector2 anchoredPosition_from;
    public Vector2 sizeDelta_to;
    public Vector2 anchoredPosition_to;

    public RTlerp(RectTransform rt_from, RectTransform rt_to = null) {
        sizeDelta_from        = rt_from.sizeDelta;
        anchoredPosition_from = rt_from.anchoredPosition;
        if (rt_to == null) return;
        sizeDelta_to        = rt_to.sizeDelta;
        anchoredPosition_to = rt_to.anchoredPosition;
    }

    public void SetFrom(RectTransform rt) {
        sizeDelta_from        = rt.sizeDelta;
        anchoredPosition_from = rt.anchoredPosition;
    }

    public void SetTo(RectTransform rt) {
        sizeDelta_to        = rt.sizeDelta;
        anchoredPosition_to = rt.anchoredPosition;
    }

    public void Lerp(RectTransform rt, float position) {
        rt.sizeDelta        = Vector2.Lerp(sizeDelta_from,        sizeDelta_to,        Mathf.Clamp01(position));
        rt.anchoredPosition = Vector2.Lerp(anchoredPosition_from, anchoredPosition_to, Mathf.Clamp01(position));
    }
}

public static class RectTransformExtension {
    public static void SetRTlerp(this RectTransform rt, RTlerp rtl, float position) {
        rtl.Lerp(rt, position);
    }
}