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

using UnityEngine;
using UnityEngine.UI;

/// <summary>
/// Tween the camera's field of view.
/// </summary>

[RequireComponent(typeof(Camera))]
public class TweenFOV : Tweener
{
	public float from = 45f;
	public float to = 45f;

	Camera mCam;

	public Camera cachedCamera { get { if (mCam == null) mCam = GetComponent<Camera>(); return mCam; } }

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

	public float value { get { return cachedCamera.fieldOfView; } set { cachedCamera.fieldOfView = 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 TweenFOV Begin (GameObject go, float duration, float to)
	{
		TweenFOV comp = Tweener.Begin<TweenFOV>(go, duration);
		comp.from = comp.value;
		comp.to = to;

		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; }
}