using UnityEngine;
using System.Collections;

public class FlyCamera : MonoBehaviour {
	
	/**
     * Writen by Windexglow 11-13-10.  Use it, edit it, steal it I don't care.
     * Converted to C# 27-02-13 - no credit wanted.
     * Added resetRotation, RF control, improved initial mouse position, 2015-03-11 - Roi Danton.
     * Simple flycam I made, since I couldn't find any others made public.
     * Made simple to use (drag and drop, done) for regular keyboard layout
     * wasdrf : basic movement
     * shift : Makes camera accelerate
     * space : Moves camera on X and Z axis only.  So camera doesn't gain any height
     */
	
	float mainSpeed = 10f; // Regular speed.
	float shiftAdd = 25f;  // Multiplied by how long shift is held.  Basically running.
	float maxShift = 100f; // Maximum speed when holding shift.
	float camSens = .35f;  // Camera sensitivity by mouse input.
	private Vector3 lastMouse = new Vector3(Screen.width/2, Screen.height/2, 0); // Kind of in the middle of the screen, rather than at the top (play).
	private float totalRun= 1.0f;

	void Start(){
		transform.localEulerAngles = Vector3.zero;
	}

	void Update () {
		
		// Mouse input.
		lastMouse = Input.mousePosition - lastMouse;
		lastMouse = new Vector3(-lastMouse.y * camSens, lastMouse.x * camSens, 0 );
		lastMouse = new Vector3(transform.eulerAngles.x + lastMouse.x , transform.eulerAngles.y + lastMouse.y, 0);
		transform.eulerAngles = lastMouse;
		lastMouse =  Input.mousePosition;
		
		// Keyboard commands.
		Vector3 p = getDirection();
		if (Input.GetKey (KeyCode.LeftShift)){
			totalRun += Time.deltaTime;
			p  = p * totalRun * shiftAdd;
			p.x = Mathf.Clamp(p.x, -maxShift, maxShift);
			p.y = Mathf.Clamp(p.y, -maxShift, maxShift);
			p.z = Mathf.Clamp(p.z, -maxShift, maxShift);
		}
		else{
			totalRun = Mathf.Clamp(totalRun * 0.5f, 1f, 1000f);
			p = p * mainSpeed;
		}
		
		p = p * Time.deltaTime;
		Vector3 newPosition = transform.position;
		if (Input.GetKey(KeyCode.V)){ //If player wants to move on X and Z axis only
			transform.Translate(p);
			newPosition.x = transform.position.x;
			newPosition.z = transform.position.z;
			transform.position = newPosition;
		}
		else{
			transform.Translate(p);
		}
		
	}
	
	private Vector3 getDirection() {
		Vector3 p_Velocity = new Vector3();
		if (Input.GetKey (KeyCode.W)){
			p_Velocity += new Vector3(0, 0 , 1);
		}
		if (Input.GetKey (KeyCode.S)){
			p_Velocity += new Vector3(0, 0, -1);
		}
		if (Input.GetKey (KeyCode.A)){
			p_Velocity += new Vector3(-1, 0, 0);
		}
		if (Input.GetKey (KeyCode.D)){
			p_Velocity += new Vector3(1, 0, 0);
		}
		if (Input.GetKey (KeyCode.R)){
			p_Velocity += new Vector3(0, 1, 0);
		}
		if (Input.GetKey (KeyCode.F)){
			p_Velocity += new Vector3(0, -1, 0);
		}
		return p_Velocity;
	}
	
	public void resetRotation(Vector3 lookAt) {
		transform.LookAt(lookAt);
	}
}