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

public class magnetGun : MonoBehaviour {

	public Camera camera;
	public GameObject crossHair;
	public thirdPersonController playerController;

	public string L_TRIGGER_INPUT;
	public string R_TRIGGER_INPUT;
	public string L_BUTTON_INPUT;
	public string R_BUTTON_INPUT;
	private bool L_Trigger_Down;
	
	public bool topScreen = true;
	private float playerScreen = 2;

	public GameObject gravityWell;
	private Collider GravityTarget;
	private Vector3 rayHitPoint;
	private Vector3 targetOffset;

	public float objectSpeed;
	public float magnetRange = 20;
	public float maxPullSpeed = 30;
	public float rotateSpeed;
	public float minDistance = 3.0f;
	public float impulsePower = 50.0f;

	private RigidbodyConstraints originalConstrants;
	private bool originalGravity;

	private float maxWalkSpeed;
	private Renderer lastTargetRenderer;
	private Color lastTargetColour;
	// Use this for initialization
	void Start () {
		if (topScreen)
			playerScreen = 2;
		else
			playerScreen = -1;

		maxWalkSpeed = playerController.movementSpeed;

	
	}
	
	// Update is called once per frame
	void Update () {

		float triggerL = Input.GetAxis(L_TRIGGER_INPUT);
		float triggerR = Input.GetAxis (R_TRIGGER_INPUT);


		Collider target = testItem ();

		crossHair.GetComponent<RawImage> ().color = Color.white;
		if (target != null){
			if (target.GetComponent<Collider>().tag == "moveable"){
				Debug.Log("Moveable Item");
				crossHair.GetComponent<RawImage>().color = Color.red;
				if (Vector3.Distance (rayHitPoint, camera.transform.position) <= minDistance) {
					crossHair.GetComponent<RawImage>().color = Color.blue;
				}
			}
			}

		updateColors (target);



		if (triggerL > 0) {
			if (!L_Trigger_Down) {
				pickUpItem (target);
				L_Trigger_Down = true;
			}
		} else {
			L_Trigger_Down = false;
			dropItem(GravityTarget);
		}

		impulsePush (target);
		moveItem (GravityTarget);
		pullItem (triggerR);
		rotateInput (GravityTarget);
		cameraRotateTest (GravityTarget);



	}



	private Collider testItem(){
		RaycastHit hit;

		//Vector3 rayDirection = camera.transform.rotation * Vector3.forward;
		//Ray ray = camera.ScreenPointToRay(new Vector3(Screen.width/2, Screen.height/2 + (Screen.height/6 * playerScreen), 0));
		
		Ray ray = camera.ScreenPointToRay(crossHair.transform.position);

		Debug.DrawRay (ray.origin, ray.direction*magnetRange, Color.green);

		if (Physics.Raycast (ray, out hit, magnetRange)) {
			if (hit.collider.tag == "moveable"){
				Debug.DrawRay (ray.origin,ray.direction*magnetRange, Color.red);
				rayHitPoint = hit.point;

			}


		}
		return hit.collider;
	}

	private void pickUpItem(Collider item){
		if (item != null) {
			if (item.tag == "moveable"){
				originalConstrants = item.attachedRigidbody.constraints;
				originalGravity = item.attachedRigidbody.useGravity;

				item.attachedRigidbody.useGravity = false;
				item.attachedRigidbody.drag = 3.0f;
				item.attachedRigidbody.constraints = RigidbodyConstraints.FreezeRotation | originalConstrants;
				//camera.transform.LookAt(item.transform.position);
				//playerController.cameraX = camera.transform.eulerAngles.x;
				//playerController.cameraY = camera.transform.eulerAngles.y;
				gravityWell.transform.position = rayHitPoint;
				GravityTarget = item;
				targetOffset = GravityTarget.transform.position - rayHitPoint + (Vector3.up * 0.05f);



				playerController.movementSpeed = 200.0f;

				if (!topScreen){
					playerController.cameraSpeedX = 0.0f;
					playerController.cameraSpeedY = 0.0f;
				}
			}
		}
	}

	private void impulsePush (Collider item){
		if (item != null) {
			if (item.tag == "moveable" && Input.GetButtonDown("Quick Push")){
				Vector3 direction = (transform.position - item.transform.position).normalized;

				item.attachedRigidbody.AddForce(direction * impulsePower * maxPullSpeed* item.attachedRigidbody.mass,ForceMode.Impulse );
			}
		}
	}

	private void moveItem(Collider item){
		if (item != null) {
			float step = objectSpeed * Time.deltaTime;
			Vector3 direction = gravityWell.transform.position - item.transform.position + targetOffset;
			direction = Vector3.ClampMagnitude(direction,1.0f);

			item.attachedRigidbody.AddForce(direction * objectSpeed * Time.deltaTime);

		}
	}

	private void dropItem(Collider item){
		if (item != null) {
			item.attachedRigidbody.useGravity = originalGravity;
			item.attachedRigidbody.drag = 0.0f;
			item.attachedRigidbody.constraints = originalConstrants;

			if(topScreen)
				item.attachedRigidbody.velocity = Vector3.ClampMagnitude (item.attachedRigidbody.velocity, 5);
			GravityTarget = null;

			
			playerController.movementSpeed = maxWalkSpeed;

			playerController.cameraSpeedX = 250.0f;
			playerController.cameraSpeedY = 120.0f;
		}

	}

	private void pullItem(float speed){

		float step = maxPullSpeed * speed * Time.deltaTime;

		Vector3 maxPull;
		maxPull = camera.transform.position + (camera.transform.rotation * Vector3.forward);


		if ((Vector3.Distance (gravityWell.transform.position, camera.transform.position) > minDistance && Vector3.Distance (gravityWell.transform.position, camera.transform.position) < magnetRange) || maxPullSpeed<1) {
			gravityWell.transform.position = Vector3.MoveTowards (gravityWell.transform.position, maxPull, step);

			if ((Vector3.Distance (gravityWell.transform.position, camera.transform.position) > magnetRange) && !topScreen)
				dropItem (GravityTarget);
		}

	}

	private void rotateInput(Collider item){
		if (item != null) {
				if (Input.GetButtonDown(L_BUTTON_INPUT))
					StartCoroutine (rotateItem(item,new Vector3 (0,90,0),0.3f));
				if (Input.GetButtonDown(R_BUTTON_INPUT))
					StartCoroutine (rotateItem(item,new Vector3 (90,0,0),0.3f));
		}
	}

	IEnumerator rotateItem (Collider item, Vector3 byAngles, float inTime){

		Quaternion startAngle = item.transform.rotation;
		Quaternion endAngle = Quaternion.Euler (item.transform.eulerAngles + byAngles);

		for (float i = 0; i < 1; i+=Time.deltaTime/inTime) {
			item.transform.rotation = Quaternion.Lerp(startAngle,endAngle,i);
			yield return null;
		}


	}

	public void cameraRotateTest(Collider item){

		if (item != null) {
			//Debug.Log ("distance test: " + Vector3.Distance (gravityWell.transform.position, camera.transform.position));
			if (Vector3.Distance (gravityWell.transform.position, camera.transform.position) <= minDistance) {
				playerController.cameraSpeedX = 250.0f;
				playerController.cameraSpeedY = 120.0f;
			} else {
				playerController.cameraSpeedX = 0.0f;
				playerController.cameraSpeedY = 0.0f;
			}

		}
	}

	public void updateColors(Collider target){

		if (target != null && target.tag == "moveable") {
			lastTargetRenderer = target.GetComponent<Renderer> ();

			if (lastTargetRenderer.material.color != Color.white) {
				lastTargetColour = lastTargetRenderer.material.color;
				lastTargetRenderer.material.color = Color.white;
			}


		} else {
			if (lastTargetRenderer != null)
				lastTargetRenderer.material.color = lastTargetColour;
		}


	}
	
}