using System;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;

[RequireComponent(typeof(RectTransform))]
public class MarginElement : UIBehaviour, ILayoutElement
{
	public float minWidth
	{
		get
		{
			return this.preferredWidth;
		}
	}

	public float preferredWidth { get; private set; }

	public float flexibleWidth
	{
		get
		{
			return 0f;
		}
	}

	public float minHeight
	{
		get
		{
			return this.preferredHeight;
		}
	}

	public float preferredHeight { get; private set; }

	public float flexibleHeight
	{
		get
		{
			return 0f;
		}
	}

	public int layoutPriority
	{
		get
		{
			return this._layoutPriority;
		}
	}

	public void AffectSize(float? preferredWidth, float? preferredHeight)
	{
		this._preferredWidth = preferredWidth;
		this._preferredHeight = preferredHeight;
		this.TrackerLogics();
	}

	public void CalculateLayoutInputHorizontal()
	{
		this.TrackerLogics();
		if (this._preferredWidth != null)
		{
			this.preferredWidth = this._preferredWidth.Value;
		}
		else
		{
			this.preferredWidth = -1f;
		}
	}

	public void CalculateLayoutInputVertical()
	{
		this.TrackerLogics();
		if (this._preferredHeight != null)
		{
			this.preferredHeight = this._preferredHeight.Value;
		}
		else
		{
			this.preferredHeight = -1f;
		}
	}

	private void TrackerLogics()
	{
		if (this._rectTransform == null)
		{
			this._rectTransform = base.GetComponent<RectTransform>();
		}
		this._tracker.Clear();
		DrivenTransformProperties drivenProperties;
		if (this._preferredWidth != null && this._preferredHeight != null)
		{
			drivenProperties = DrivenTransformProperties.SizeDelta;
		}
		else if (this._preferredWidth != null)
		{
			drivenProperties = DrivenTransformProperties.SizeDeltaX;
		}
		else
		{
			if (this._preferredHeight == null)
			{
				return;
			}
			drivenProperties = DrivenTransformProperties.SizeDeltaY;
		}
		this._tracker.Add(this, this._rectTransform, drivenProperties);
	}

	[SerializeField]
	private int _layoutPriority = 1;

	private DrivenRectTransformTracker _tracker;

	private RectTransform _rectTransform;

	private float? _preferredWidth;

	private float? _preferredHeight;
}