paint-ui/core/commands/move-command.ts

import { BaseCommand } from './base-command';
import { useLayerStore } from '@/store/layer-store';

/**
 * Command for moving a layer
 * Captures start and end positions for undo/redo
 */
export class MoveCommand extends BaseCommand {
  private layerId: string;
  private beforePosition: { x: number; y: number };
  private afterPosition: { x: number; y: number } | null = null;

  constructor(layerId: string, beforePosition: { x: number; y: number }) {
    super('Move Layer');
    this.layerId = layerId;
    this.beforePosition = beforePosition;
  }

  /**
   * Capture the final position after the move is complete
   */
  captureAfterPosition(x: number, y: number): void {
    this.afterPosition = { x, y };
  }

  execute(): void {
    if (!this.afterPosition) {
      // No-op on first execute (position already set during drag)
      return;
    }

    // Restore after position (for redo)
    const { updateLayer } = useLayerStore.getState();
    updateLayer(this.layerId, {
      x: this.afterPosition.x,
      y: this.afterPosition.y,
      updatedAt: Date.now(),
    });
  }

  undo(): void {
    const { updateLayer } = useLayerStore.getState();
    updateLayer(this.layerId, {
      x: this.beforePosition.x,
      y: this.beforePosition.y,
      updatedAt: Date.now(),
    });
  }

  /**
   * Check if this move actually changed position
   */
  hasChanged(): boolean {
    if (!this.afterPosition) return false;
    return (
      this.beforePosition.x !== this.afterPosition.x ||
      this.beforePosition.y !== this.afterPosition.y
    );
  }
}