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

public class PlayerCamera : MonoBehaviour
{
    public float normalSpeed = 0.0035f;
    public float shiftSpeed = 0.06f;
    public float zoomSpeed = -10.0f;
    public float rotateSpeed = 0.1f;

    public float maxHeight = 40f;
    public float minHeight = 6f;

    public Vector2 startMouseP;
    public Vector2 dragMouseP;

    private float speed;
    // Start is called before the first frame update
    void Start()
    {
        
    }

    // Update is called once per frame
    void Update()
    {
        // shift to speed UP
        if (Input.GetKey(KeyCode.LeftShift))
        {
            speed = shiftSpeed;
            zoomSpeed = 20.0f;
        }
        else
        {
            speed = normalSpeed;
            zoomSpeed = 10.0f;
        }

        float hsp = transform.position.y * speed * Input.GetAxis("Horizontal"); // horizontal movement speed
        float vsp = transform.position.y * speed * Input.GetAxis("Vertical"); // vertical movement speed
        float scrollSp = Mathf.Log(transform.position.y) * -zoomSpeed * Input.GetAxis("Mouse ScrollWheel"); // scroll speed

        // camera height limit
        if (transform.position.y + scrollSp > maxHeight)
        {
            scrollSp = maxHeight - transform.position.y;
        }
        else if (transform.position.y + scrollSp < minHeight)
        {
            scrollSp = minHeight - transform.position.y;
        }

        Vector3 verticalMove = new Vector3(0,scrollSp,0); // vertical movement
        Vector3 lateralMove = hsp * transform.right; // lateral movement in global world ignore camera facing
        Vector3 fowardMove = transform.forward; // forward movement in global world ignore camera facing
        fowardMove.y = 0; // ignore y axis
        fowardMove = vsp * fowardMove.normalized; // normalize the vector

        Vector3 move = verticalMove + lateralMove + fowardMove; // total movement
        transform.position += move; // move the camera
        CameraRotation();
    }

    void CameraRotation()
    {
        // camera rotation while press middle mousebutton
        if(Input.GetMouseButtonDown(2))
        {
            startMouseP = Input.mousePosition;
        }

        if (Input.GetMouseButton(2))
        {
            dragMouseP = Input.mousePosition;

            float dx = (dragMouseP - startMouseP).x * rotateSpeed;
            float dy = (dragMouseP - startMouseP).y * rotateSpeed;

            transform.rotation *= Quaternion.Euler(new Vector3(0, dx, 0));
            transform.GetChild(0).rotation *= Quaternion.Euler(new Vector3(-dy, 0, 0));

            startMouseP = dragMouseP;
        }
    }
}