// systems/SelectionSystem.js
import { clearSelection, addToSelection, setActiveUnit } from './ControlMode.js';

export class SelectionSystem {
  constructor(scene) {
    this.scene = scene;
    this.selectionBox = null;

    scene.events.on('selection-start', this.onStart, this);
    scene.events.on('selection-update', this.onUpdate, this);
    scene.events.on('selection-end', this.onEnd, this);
    scene.events.on('select-unit', this.onSelectUnit, this);
  }

  onStart(pos) {
    if (!this.selectionBox) {
      this.selectionBox = this.scene.add.rectangle(pos.x, pos.y, 1, 1, 0x00ff00, 0.3)
        .setStrokeStyle(1, 0xffffff)
        .setVisible(true);
    } else {
      this.selectionBox.setPosition(pos.x, pos.y).setSize(1, 1).setVisible(true);
    }
  }

  onUpdate(rect) {
    if (this.selectionBox && this.selectionBox.visible) {
      // 更新选择框的位置和大小
      this.selectionBox.setPosition(rect.centerX, rect.centerY);
      this.selectionBox.setSize(rect.width, rect.height);
    }
  }

  onSelectUnit(unit) {
    // 清除所有单位的选中状态
    this.scene.unitGroup.getChildren().forEach(u => {
      if (u.setSelected) {
        u.setSelected(false);
      }
    });
    
    // 清除当前选择
    clearSelection();
    
    // 选择点击的单位
    setActiveUnit(unit);
    addToSelection(unit);
    
    // 设置选中状态
    if (unit.setSelected) {
      unit.setSelected(true);
    }
    
    this.scene.events.emit('units-selected', [unit]);
  }
  
  onEnd(rect) {
    if (this.selectionBox) {
      this.selectionBox.setVisible(false);
    }

    const units = this.scene.unitGroup.getChildren();
    const selected = units.filter(unit => {
      const unitRect = unit.getBounds();
      return Phaser.Geom.Rectangle.Overlaps(rect, unitRect);
    });
    


    // 先清除所有单位的选中状态
    units.forEach(unit => {
      if (unit.setSelected) {
        unit.setSelected(false);
      }
    });

    clearSelection();

    if (selected.length > 0) {
      // 先设置激活单位
      setActiveUnit(selected[0]);
      // 然后添加所有选中的单位（包括激活单位）
      selected.forEach(unit => {
        addToSelection(unit);
        if (unit.setSelected) {
          unit.setSelected(true);
        }
      });
      this.scene.events.emit('units-selected', selected);
    }
  }
}