using Base;
using UnityEngine;

namespace CameraControl
{
    public class CameraControl : Utils.MonoSingleton<CameraControl>, ITick, ITickUI
    {
        // 当前被聚焦的目标实体
        public Entity.Entity focusedEntity = null;

        // Camera movement variables
        private Vector3 _dragOrigin;
        private bool _isDragging = false;
        private float _zoomSpeed = 5f;
        private float _minZoom = 2f;
        private float _maxZoom = 20f;

        private Camera _camera;

        protected override void OnStart()
        {
            _camera = Camera.main;
            if (_camera == null)
            {
                _camera = FindFirstObjectByType<Camera>();
            }
        }
        public void Tick()
        {
            if (focusedEntity)
            {
                // Follow the focused entity's position
                var targetPosition = new Vector3(
                    focusedEntity.Position.x,
                    focusedEntity.Position.y,
                    _camera.transform.position.z);

                _camera.transform.position = Vector3.Lerp(
                    _camera.transform.position,
                    targetPosition,
                    Time.fixedDeltaTime * 5f);
            }
        }

        public void TickUI()
        {
            HandleMiddleMouseDrag();
            HandleMouseZoom();
        }

        private void HandleMiddleMouseDrag()
        {
            // Start drag
            if (Input.GetMouseButtonDown(2)) // Middle mouse button
            {
                _dragOrigin = _camera.ScreenToWorldPoint(Input.mousePosition);
                _isDragging = true;
                focusedEntity = null; // Clear focus when manually moving camera
            }

            // During drag
            if (Input.GetMouseButton(2) && _isDragging)
            {
                var difference = _dragOrigin - _camera.ScreenToWorldPoint(Input.mousePosition);
                _camera.transform.position += difference;
            }

            // End drag
            if (Input.GetMouseButtonUp(2))
            {
                _isDragging = false;
            }
        }

        private void HandleMouseZoom()
        {
            var scroll = Input.GetAxis("Mouse ScrollWheel");
            if (scroll == 0) return;
            var newSize = _camera.orthographicSize - scroll * _zoomSpeed;
            _camera.orthographicSize = Mathf.Clamp(newSize, _minZoom, _maxZoom);
        }

  
    }
}