//----------------------------------------------
//            NGUI: Next-Gen UI kit
// Copyright © 2011-2014 Tasharen Entertainment
//----------------------------------------------

using UnityEngine;
using UnityEngine.UI;

/// <summary>
/// Tween the object's position.
/// </summary>

public class TweenPosition : Tweener
{
	public Vector3 from;
	public Vector3 to;

	[HideInInspector]
	public bool worldSpace = false;

	Transform mTrans;
    RectTransform mRectTrans;

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

    public RectTransform cachedRectTransform { get { if (mRectTrans == null) mRectTrans = GetComponent<RectTransform>(); return mRectTrans; } }

	/// <summary>
	/// Tween's current value.
	/// </summary>

	public Vector3 value
	{
		get
		{
			return worldSpace ? cachedTransform.position : cachedTransform.localPosition;
		}
		set
		{
            if (worldSpace) cachedTransform.position = value;
            else cachedTransform.localPosition = value;
		}
	}

	/// <summary>
	/// Tween the value.
	/// </summary>

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

	/// <summary>
	/// Start the tweening operation.
	/// </summary>

	static public TweenPosition Begin (GameObject go, float duration, Vector3 pos)
	{
		TweenPosition comp = Tweener.Begin<TweenPosition>(go, duration);
		comp.from = comp.value;
		comp.to = pos;

		if (duration <= 0f)
		{
			comp.Sample(1f, true);
			comp.enabled = false;
		}
		return comp;
	}

	/// <summary>
	/// Start the tweening operation.
	/// </summary>

	static public TweenPosition Begin (GameObject go, float duration, Vector3 pos, bool worldSpace)
	{
		TweenPosition comp = Tweener.Begin<TweenPosition>(go, duration);
		comp.worldSpace = worldSpace;
		comp.from = comp.value;
		comp.to = pos;

		if (duration <= 0f)
		{
			comp.Sample(1f, true);
			comp.enabled = false;
		}
		return comp;
	}

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

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

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

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