using UnityEngine;
using System.Collections;

public class Joystick : MonoBehaviour {

	public bool view = true;

	public Vector2 output;

	public Texture2D stick;
	public Texture2D back;

	public GUIStyle stickStyle;
	public GUIStyle backStyle;

	public Vector2 position = new Vector2(0.15f, 0.75f);

	public float stickSize = 0.175f;
	public float backSize = 0.225f;

	public float activeRadius = 0.2f;

	public Vector2 input;

	public bool touched;

	void Update ()
	{
		stickStyle.normal.background = stick;
		backStyle.normal.background = back;

		float s = ((Screen.width + Screen.height) / 2) * stickSize;
		float b = ((Screen.width + Screen.height) / 2) * backSize;

		float posX = position.x * Screen.width;
		float posY = position.y * Screen.height;

		if(Application.platform == RuntimePlatform.Android)
		{
			for(int i = 0;i < Input.touchCount;i++)
			{
				float x = Input.GetTouch(i).position.x;
				float y = Screen.height - Input.GetTouch(i).position.y;

				if(Vector2.Distance( new Vector2(posX, posY), new Vector2(x, y) ) < (((Screen.width + Screen.height) / 2) * activeRadius))
				{
					input = new Vector2(x, y);
				}
			}
		}else
			input = new Vector2(Input.mousePosition.x, Screen.height - Input.mousePosition.y);

		if(Input.GetMouseButton(0) || touched)
		{
			if(Vector2.Distance( new Vector2(posX, posY), input ) < (((Screen.width + Screen.height) / 2) * activeRadius))
			{
				float x = (input.x - posX) / (b / 2);
				float y = -(input.y - posY) / (b / 2);
				output = new Vector2(x, y);
			}
		}else
		{
			output = Vector2.zero;
		}
	}

	void OnGUI ()
	{
		if(view)
		{
			float s = ((Screen.width + Screen.height) / 2) * stickSize;
			float b = ((Screen.width + Screen.height) / 2) * backSize;

			float stickX = Screen.width * position.x - s / 2 - Mathf.Clamp(-output.x, -1f, 1f) * (b / 2);
			float stickY = Screen.height * position.y - s / 2 - Mathf.Clamp(output.y, -1f, 1f) * (b / 2);

			GUI.Box ( new Rect(stickX, stickY, s, s), "", stickStyle); // Stick

			GUI.Box ( new Rect(Screen.width * position.x - b / 2, Screen.height * position.y - b / 2, b, b), "", backStyle); // Back
		}
	}
}