using System;
using UnityEngine;

[AddComponentMenu("NGUI/Tween/Tween Position Y")]
public class TweenPositionY : UITweener
{
	public float from;

	public float to;

	[HideInInspector]
	public bool worldSpace;

	private Transform mTrans;

	private UIRect mRect;

	public Transform cachedTransform
	{
		get
		{
			if (mTrans == null)
			{
				mTrans = base.transform;
			}
			return mTrans;
		}
	}

	[Obsolete("Use 'value' instead")]
	public float positionY
	{
		get
		{
			return Yvalue;
		}
		set
		{
			Yvalue = value;
		}
	}

	public float Yvalue
	{
		get
		{
			if (!worldSpace)
			{
				return cachedTransform.localPosition.y;
			}
			return cachedTransform.position.y;
		}
		set
		{
			if (mRect == null || !mRect.isAnchored || worldSpace)
			{
				if (worldSpace)
				{
					cachedTransform.position = new Vector3(cachedTransform.position.x, value, cachedTransform.position.z);
				}
				else
				{
					cachedTransform.localPosition = new Vector3(cachedTransform.localPosition.x, value, cachedTransform.localPosition.z);
				}
			}
			else
			{
				value -= cachedTransform.localPosition.y;
				NGUIMath.MoveRect(mRect, 0f, value);
			}
		}
	}

	private void Awake()
	{
		mRect = GetComponent<UIRect>();
	}

	protected override void OnUpdate(float factor, bool isFinished)
	{
		Yvalue = from * (1f - factor) + to * factor;
	}

	public static TweenPosition Begin(GameObject go, float duration, Vector3 pos)
	{
		TweenPosition tweenPosition = UITweener.Begin<TweenPosition>(go, duration);
		tweenPosition.from = tweenPosition.value;
		tweenPosition.to = pos;
		if (duration <= 0f)
		{
			tweenPosition.Sample(1f, isFinished: true);
			tweenPosition.enabled = false;
		}
		return tweenPosition;
	}

	public static TweenPosition Begin(GameObject go, float duration, Vector3 pos, bool worldSpace)
	{
		TweenPosition tweenPosition = UITweener.Begin<TweenPosition>(go, duration);
		tweenPosition.worldSpace = worldSpace;
		tweenPosition.from = tweenPosition.value;
		tweenPosition.to = pos;
		if (duration <= 0f)
		{
			tweenPosition.Sample(1f, isFinished: true);
			tweenPosition.enabled = false;
		}
		return tweenPosition;
	}

	[ContextMenu("Set 'From' to current value")]
	public override void SetStartToCurrentValue()
	{
		from = Yvalue;
	}

	[ContextMenu("Set 'To' to current value")]
	public override void SetEndToCurrentValue()
	{
		to = Yvalue;
	}

	[ContextMenu("Assume value of 'From'")]
	private void SetCurrentValueToStart()
	{
		Yvalue = from;
	}

	[ContextMenu("Assume value of 'To'")]
	private void SetCurrentValueToEnd()
	{
		Yvalue = to;
	}
}