SelectionInputSystem.cs

using System;
using Leopotam.EcsLite;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Input;
using RTS;

public class SelectionInputSystem : IEcsRunSystem
{
    private EcsWorld _world;
    private EcsPool<SelectionBox> _selectionPool;
    private int _selectionEntity = -1;  // ID сущности с selection box (если активна)

    public Action startSelect;
    public Action endSelect;

    private Camera _camera;
    public SelectionInputSystem(EcsWorld world, Camera camera)
    {
        _world = world;
        _camera = camera;
        _selectionPool = _world.GetPool<SelectionBox>();
    }

    public void Run(IEcsSystems systems)
    {
        Vector2 mousePosition = Game1.MouseGlobalPosition;

        // Если левая кнопка только что нажата
        if (Game1.CurrentMouseState.LeftButton == ButtonState.Pressed && Game1.PreviousMouseState.LeftButton == ButtonState.Released)
        {
            // Создаём новую сущность для selection box
            _selectionEntity = _world.NewEntity();
            ref SelectionBox selection = ref _selectionPool.Add(_selectionEntity);
            selection.StartPosition = mousePosition;
            selection.CurrentPosition = mousePosition;
            selection.IsActive = true;
            selection.Bounds = new Rectangle((int)mousePosition.X, (int)mousePosition.Y, 0, 0);
            startSelect?.Invoke();
        }
        // Если левая кнопка зажата и selection активна
        else if (Game1.CurrentMouseState.LeftButton == ButtonState.Pressed && _selectionEntity != -1 && _selectionPool.Has(_selectionEntity))
        {
            ref SelectionBox selection = ref _selectionPool.Get(_selectionEntity);
            selection.CurrentPosition = mousePosition;
            // Вычисляем границы: от min(start, current) до max(start, current)
            int x = (int)MathHelper.Min(selection.StartPosition.X, mousePosition.X);
            int y = (int)MathHelper.Min(selection.StartPosition.Y, mousePosition.Y);
            int width = (int)MathHelper.Max(selection.StartPosition.X, mousePosition.X) - x;
            int height = (int)MathHelper.Max(selection.StartPosition.Y, mousePosition.Y) - y;
            selection.Bounds = new Rectangle(x, y, width, height);

        }
        // Если левая кнопка отпущена и selection активна
        else if (Game1.CurrentMouseState.LeftButton == ButtonState.Released && Game1.PreviousMouseState.LeftButton == ButtonState.Pressed && _selectionEntity != -1)
        {
            // Деактивируем selection box (здесь можно добавить логику выделения юнитов внутри Bounds)
            if (_selectionPool.Has(_selectionEntity))
            {
                ref SelectionBox selection = ref _selectionPool.Get(_selectionEntity);
                selection.IsActive = false;
                // Опционально: удалить сущность или оставить для рендеринга последнего состояния
                // _world.DelEntity(_selectionEntity);
                // _selectionEntity = -1;

            }
        }
    }
}