using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class FirstPersonController : MonoBehaviour
{
    // References
    public Transform cameraTransform;
    public CharacterController characterController;

    // Player settings
    public float cameraSensitivity;
    public float moveSpeed;
    public float moveInputDeadZone;

    // Touch detection
    int leftFingerId, rightFingerId;
    float halfScreenWidth;
    float mostScreenHeight;

    // Camera control
    Vector2 lookInput;
    float cameraPitch;

    // Player movement
    Vector2 moveTouchStartPosition;
    Vector2 moveInput;
    bool activeCtrl;

    // Start is called before the first frame update
    void Start()
    {
        // id = -1 means the finger is not being tracked
        leftFingerId = -1;
        rightFingerId = -1;

        // only calculate once
        halfScreenWidth = Screen.width / 2;
        mostScreenHeight = Screen.height * 7 / 10;
        activeCtrl = true;


        // calculate the movement input dead zone
        moveInputDeadZone = Mathf.Pow(Screen.height / moveInputDeadZone, 2);
    }
    public void activateControl()
    {
        activeCtrl = true;
    }
    public void deactivateControl()
    {
        activeCtrl = false;
    }

    // Update is called once per frame
    void Update()
    {
        if(activeCtrl == true)
        {
            GetTouchInput();


            if (rightFingerId != -1)
            {
                // Ony look around if the right finger is being tracked
                Debug.Log("Rotating");
                LookAround();
            }

            if (leftFingerId != -1)
            {
                // Ony move if the left finger is being tracked
                Debug.Log("Moving");
                Move();
            }
        }
    }
        // Handles input
       

    void GetTouchInput()
    {
        // Iterate through all the detected touches
        for (int i = 0; i < Input.touchCount; i++)
        {

            Touch t = Input.GetTouch(i);

            // Check each touch's phase
            switch (t.phase)
            {
                case TouchPhase.Began:

                    if (t.position.x < halfScreenWidth && leftFingerId == -1 && t.position.y < mostScreenHeight)
                    {
                        // Start tracking the left finger if it was not previously being tracked
                        leftFingerId = t.fingerId;

                        // Set the start position for the movement control finger
                        moveTouchStartPosition = t.position;
                    }
                    else if (t.position.x > halfScreenWidth && rightFingerId == -1 && t.position.y < mostScreenHeight)
                    {
                        // Start tracking the rightfinger if it was not previously being tracked
                        rightFingerId = t.fingerId;
                    }

                    break;
                case TouchPhase.Ended:
                case TouchPhase.Canceled:

                    if (t.fingerId == leftFingerId)
                    {
                        // Stop tracking the left finger
                        leftFingerId = -1;
                        Debug.Log("Stopped tracking left finger");
                    }
                    else if (t.fingerId == rightFingerId)
                    {
                        // Stop tracking the right finger
                        rightFingerId = -1;
                        Debug.Log("Stopped tracking right finger");
                    }

                    break;
                case TouchPhase.Moved:

                    // Get input for looking around
                    if (t.fingerId == rightFingerId)
                    {
                        lookInput = -t.deltaPosition * cameraSensitivity * Time.deltaTime;
                    }
                    else if (t.fingerId == leftFingerId)
                    {

                        // calculating the position delta from the start position
                        moveInput = t.position - moveTouchStartPosition;
                    }

                    break;
                case TouchPhase.Stationary:
                    // Set the look input to zero if the finger is still
                    if (t.fingerId == rightFingerId)
                    {
                        lookInput = Vector2.zero;
                    }
                    break;
            }
        }
    }

    void LookAround()
    {

        // vertical (pitch) rotation
        cameraPitch = Mathf.Clamp(cameraPitch - lookInput.y, -90f, 90f);
        cameraTransform.localRotation = Quaternion.Euler(cameraPitch, 0, 0);

        // horizontal (yaw) rotation
        transform.Rotate(transform.up, lookInput.x);
    }

    void Move()
    {

        // Don't move if the touch delta is shorter than the designated dead zone
        if (moveInput.sqrMagnitude <= moveInputDeadZone) return;

        // Multiply the normalized direction by the speed
        Vector2 movementDirection = moveInput.normalized * moveSpeed * Time.deltaTime;
        // Move relatively to the local transform's direction
        characterController.Move(transform.right * movementDirection.x + transform.forward * movementDirection.y);
    }

}