using UnityEngine;
using System.Collections;

public class TouchAndDrag : MonoBehaviour {
    public float speed = 10f;
    public Camera camera;
    bool hasTappedObject = false;

    void Update () {
        if (Input.touchCount > 0) { // if the user is touching the screen
            if (Input.GetTouch(0).phase == TouchPhase.Began) { // if it's an initial touch
                Vector2 worldPoint = Camera.main.ScreenToWorldPoint( Input.touches[0].position );
                RaycastHit2D hit = Physics2D.Raycast( worldPoint, Vector2.zero ); // cast a ray from the finger position into the scene
                if (hit != null && hit.collider != null) { // if the ray hits something
                    Transform objectHit = hit.transform;
                    if (objectHit.tag == "Paddle") { // if the object hit is tagged as "paddle" (you could use name or any other parameter here, I just want to be sure the user is tapping the right thing)
                        Debug.Log("Test");
                        hasTappedObject = true; // set this variable to true
                    }
                }
            } else if (Input.GetTouch(0).phase == TouchPhase.Moved) { // else it the user already has his finger on the screen and is moving it around
                if (hasTappedObject) { // if the user tapped the paddle
                    Vector2 touchDeltaPosition = Input.GetTouch(0).deltaPosition; // get the movement of the finger
                    transform.Translate(0, touchDeltaPosition.y * speed, 0);     // move the paddle object by the amount of the movement of the finger
                }
            } else if (Input.GetTouch(0).phase == TouchPhase.Ended) { // if the user lifts his finger from the screen
                hasTappedObject = false; // tell unity that he's not touching any object
            }
        }
    }
}