using UnityEngine;
using System.Collections;

public class CameraClass : MonoBehaviour
{
	public Transform target;

	private const float deg = Mathf.Deg2Rad;
	
	private const float distance = 5.0f; //Lateral distance of camera from player.
	private const float zoomMax = 10f, zoomMin = 4f; //Min-Max camera zoom levels
	private float zoomTarget = 8,
	zoomVel = 0;
	
	//Camera rotation variables
	private float angle = 0,
	targetangle = 0.0f, 
	currentVel = 0.0f;
	
	private float yoffset = 1.8f,
	targetHeight = 0.0f,
	curHeight = 0.0f,
	verticalVel = 0.0f;
	
	private const float DEFAULT_ANGLE = 45;
	private const float DEFAULT_ZOOM = 8;
	
	private const float twoPi = Mathf.PI * 2;
	private const float deg45 = Mathf.PI / 4;
	
	private Vector3 point;
	
	private bool allowSmoothRot; //True when camera turn key is still held after initial rotation
	
	void Start () 
	{
		angle = deg45;
		targetangle = angle;
		
		point = target.transform.position;
		curHeight = point.y;
		targetHeight = curHeight;
		transform.LookAt(new Vector3(point.x, point.y - 0.5f, point.z));
	}
	
	void Update ()
	{
		//Camera Reset
		if(Input.GetButtonDown("Camera Reset"))
		{
			if(angle <= deg*180 && angle != deg*DEFAULT_ANGLE)
				targetangle = deg*DEFAULT_ANGLE;
			else if(angle > deg*180 && angle != deg*DEFAULT_ANGLE)
				targetangle = deg*(360 + DEFAULT_ANGLE);
			zoomTarget = DEFAULT_ZOOM;
		}
		//Rotate Camera 45 degrees on button press
		if(Input.GetButtonDown("Camera Left"))
		{
			targetangle += deg45;
			allowSmoothRot = false;
		}
		if(Input.GetButtonDown("Camera Right"))
		{
			targetangle -= deg45;
			allowSmoothRot = false;
		}

		//After initial rotation--
		//Move the camera left and right at a static speed, and update the target angle accordingly
		if(Input.GetButton("Camera Left"))
		{
			if(allowSmoothRot) angle += deg*1f;
			
			if(angle >= targetangle - deg*5)
			{
				targetangle += deg45;
				allowSmoothRot = true;
			}
		}
		else if(Input.GetButton("Camera Right"))
		{
			if(allowSmoothRot) angle -= deg*1f;
			
			if(angle <= targetangle + deg*5)
			{
				targetangle -= deg45;
				allowSmoothRot = true;
			}
		}

		//Move the camera toward/away from the player
		if(Input.GetButton("Camera Zoom In") && zoomTarget > zoomMin)
		{
			if(GetComponent<Camera>().orthographicSize < zoomTarget + 0.25f)
				zoomTarget -= 2f;
		}
		else if(Input.GetButton("Camera Zoom Out") && zoomTarget < zoomMax)
		{
			if(GetComponent<Camera>().orthographicSize > zoomTarget - 0.25f)
				zoomTarget += 2f;
		}
		if(GetComponent<Camera>().orthographicSize != zoomTarget)
		{
			GetComponent<Camera>().orthographicSize = Mathf.SmoothDamp(GetComponent<Camera>().orthographicSize, zoomTarget, ref zoomVel, .1f, 8f, Time.deltaTime);
			if(GetComponent<Camera>().orthographicSize < zoomTarget+.001f && GetComponent<Camera>().orthographicSize > zoomTarget-.001f)
			{
				GetComponent<Camera>().orthographicSize = zoomTarget;
			}
		}
		
		updateCamera(true);
	}
	
	public void updateCamera(bool applyRotation)
	{
		//If the camera rotation keys are not being pressed,
		if(!allowSmoothRot || (!Input.GetButton("Camera Left") && !Input.GetButton("Camera Right")))
		{
			if(angle != targetangle && applyRotation)
			{
				//Decelerate rotation toward target angle until it is reached
				angle = Mathf.SmoothDampAngle(angle, targetangle, ref currentVel, .2f, 8f, Time.deltaTime);
			}
			
			//Correct the floating point number when within a small range of the target angle
			if(angle < targetangle + 0.001f && angle > targetangle - 0.001f)
			{
				angle = targetangle;
				angle = Mathf.Repeat(angle, twoPi);//Keeps the angle variable between 0 and twoPi
				targetangle = angle;
				allowSmoothRot = false;
			}
		}
		
		//Follow Player
		point = target.transform.position;
		
		float xoffset = Mathf.Sin(angle) * distance;
		float zoffset = Mathf.Cos(angle) * distance;
		
		targetHeight = point.y;
		curHeight = Mathf.SmoothDamp(curHeight, targetHeight, ref verticalVel, .5f, 16f, Time.deltaTime);
		
		transform.position = new Vector3(point.x + xoffset, curHeight + GetComponent<Camera>().orthographicSize / yoffset,
		                                 point.z + zoffset);
		transform.LookAt(new Vector3(point.x, curHeight - 0.5f, point.z));
	}
	
	//Returns a relative angle in Radians where "steps" is the number of
	//45 degree turns clockwise from "toward" the camera
	public float getDirection(int steps) 
	{
		return Mathf.Repeat(this.angle + (deg45 * steps), twoPi);
	}
	
	public float getAngle()
	{
		return angle;
	}
}