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

public class JoystickController : MonoBehaviour, IDragHandler, IEndDragHandler
{
    public bool isDrag = false;
    public RectTransform joystickBackground; // 摇杆背景
    public RectTransform joystick;           // 摇杆
    public Camera playerCamera;              // 摄像机
    public float rotationSpeed = 5f;         // 摄像机旋转速度

    private Vector2 joystickInput = Vector2.zero;

    void Start()
    {
        // 初始化摇杆的位置
        joystick.anchoredPosition = Vector2.zero;
    }

    // 每帧更新摇杆的输入
    void Update()
    {
        if (joystickInput.magnitude > 0)
        {
            // 根据摇杆的输入控制摄像机旋转
            float horizontal = joystickInput.x;
            float vertical = joystickInput.y;

            // 水平旋转
            playerCamera.transform.Rotate(Vector3.up, horizontal * rotationSpeed * Time.deltaTime);

            // 垂直旋转
            playerCamera.transform.Rotate(Vector3.left, vertical * rotationSpeed * Time.deltaTime);
        }
    }

    // 摇杆拖动时更新摇杆位置和输入
    public void OnDrag(PointerEventData eventData)
    {
        isDrag = true;
        // 更新摇杆的位置
        joystick.anchoredPosition = joystickInput;

        Vector2 localPoint;
        // 将触摸位置从屏幕坐标转换为UI本地坐标
        RectTransformUtility.ScreenPointToLocalPointInRectangle(joystickBackground, eventData.position, eventData.pressEventCamera, out localPoint);
        
        // 计算摇杆的输入方向
        joystickInput = localPoint.normalized;

        // 限制摇杆的移动范围，确保它不会超出背景的边界
        if (localPoint.magnitude > joystickBackground.sizeDelta.x / 2)
        {
            joystickInput = localPoint.normalized * (joystickBackground.sizeDelta.x / 2);
        }

        
    }

    // 摇杆松开时重置摇杆位置
    public void OnEndDrag(PointerEventData eventData)
    {
        isDrag = false;
        joystick.anchoredPosition = Vector2.zero;
        joystickInput = Vector2.zero;
    }
}