ai2 extension

package edu.mit.appinventor;

import java.util.List;

import com.google.appinventor.components.annotations.DesignerComponent;
import com.google.appinventor.components.annotations.DesignerProperty;
import com.google.appinventor.components.annotations.PropertyCategory;
import com.google.appinventor.components.annotations.SimpleFunction;
import com.google.appinventor.components.annotations.SimpleObject;
import com.google.appinventor.components.annotations.SimpleProperty;
import com.google.appinventor.components.common.ComponentCategory;
import com.google.appinventor.components.common.PropertyTypeConstants;
import com.google.appinventor.components.runtime.AndroidNonvisibleComponent;
import com.google.appinventor.components.runtime.Canvas;
import com.google.appinventor.components.runtime.Component;
import com.google.appinventor.components.runtime.ComponentContainer;
import com.google.appinventor.components.runtime.ImageSprite;
import com.google.appinventor.components.runtime.errors.YailRuntimeError;

/**
 * This provides an interface for a canvas component, making it easy to create
 * grids of sprites. These grid tiles can be arranged in different sizes and
 * can be removed.
 *
 * @author Louis Van Steene
 */
@DesignerComponent(version=1,
        description="Arranges sprites on a canvas into a grid.",
        category=ComponentCategory.EXTENSION,
        nonVisible=true,
        iconName="images/extension.png")
@SimpleObject(external=true)
// @UsesPermissions()
public class GridAdapter extends AndroidNonvisibleComponent {

    private Canvas canvas;

    protected GridAdapter(ComponentContainer container) {
        super(container.$form());
    }

//  @SimpleFunction
//  public void AddGridToCanvas(Canvas canvas) {
//      this.canvas = canvas;
//  }

    @SimpleFunction(description="Turn sprites on the canvas into a grid.")
    public void GenerateGrid(int rows, int columns, List<ImageSprite> sprites) {
        if((rows * columns) < sprites.size()) {
            throw new YailRuntimeError("There aren't enough sprites in the canvas to do that.", "GridCanvas error");
        }
        try {
            for(int i = 0, row = 0, col = 0; i < sprites.size(); i++) {
                int width = canvas.Width();
                int height = canvas.Height();

                ImageSprite s = sprites.get(i);

                // set X and Y
                s.X((width / columns) * col);
                s.X((height / rows) * col);

                // set Width and Height
                s.Width(width / columns);
                s.Height(height / rows);

                // check if we have reached the end of this row
                if(col == columns - 1) {
                    // if we have, move onto the next row
                    if(row++ >= rows - 1) {
                        break;
                    }
                    // and go back to the beginning of the column
                    col = 0;
                }
            }
        } catch(Exception e) {
            throw new YailRuntimeError(e.getMessage(), "generate grid");
        }
    }

    /**
     * Returns the canvas object being concealed by a grid
     *
     * @return a {@link Canvas} in the editor
     */
    @SimpleProperty(
            category=PropertyCategory.BEHAVIOR,
            userVisible=true)
    public Component CanvasComponent() {
        return canvas;
    }

    /**
     * Specifies the canvas to be controlled by this class
     *
     * @param a {@link Canvas} in the editor
     *
     * @throws IllegalArgumentException if shape is not a legal value.
     */
    @SimpleProperty(description="The canvas to make into a grid.",
            userVisible=true)
    @DesignerProperty(editorType = PropertyTypeConstants.PROPERTY_TYPE_COMPONENT)
    public void CanvasComponent(Component component) {
        if(component instanceof Canvas) {
            canvas = (Canvas) component;
        } else {
            throw new YailRuntimeError("The CanvasComponent must be a Canvas!", "Illegal Argument");
        }
    }
}