using UnityEngine;
using System.Collections;
using System.Collections.Generic;
using UnityEngine.UI;

namespace MoreMountains.Tools
{
	/// <summary>
	/// Camera extensions
	/// </summary>
	public static class MMCameraExtensions
	{
		/// <summary>
		/// Returns the width of the camera in world space units, at the specified depths for perspective cameras, everywhere for orthographic ones
		/// </summary>
		/// <param name="camera"></param>
		/// <param name="depth"></param>
		/// <returns></returns>
		public static float MMCameraWorldSpaceWidth(this Camera camera, float depth = 0f)
		{
			if (camera.orthographic)
			{
				return camera.aspect * camera.orthographicSize * 2f;
			}
			else
			{
				float fieldOfView = camera.fieldOfView * Mathf.Deg2Rad;
				return camera.aspect * depth * Mathf.Tan(fieldOfView);
			}
		}

		/// <summary>
		/// Returns the height of the camera in world space units, at the specified depths for perspective cameras, everywhere for orthographic ones
		/// </summary>
		/// <param name="camera"></param>
		/// <param name="depth"></param>
		/// <returns></returns>
		public static float MMCameraWorldSpaceHeight(this Camera camera, float depth = 0f)
		{
			if (camera.orthographic)
			{
				return camera.orthographicSize * 2f;
			}
			else
			{
				float fieldOfView = camera.fieldOfView * Mathf.Deg2Rad;
				return depth * Mathf.Tan(fieldOfView);
			}
		}
	}
}