package cn.sinata.xldutils.view;

import android.graphics.Matrix;
import android.graphics.RectF;
import android.view.MotionEvent;

public interface ZoomableController {

  /**
   * Listener interface.
   */
  public interface Listener {

    /**
     * Notifies the view that the transform changed.
     *
     * @param transform the new matrix
     */
    void onTransformChanged(Matrix transform);
  }

  /**
   * Enables the controller. The controller is enabled when the image has been loaded.
   *
   * @param enabled whether to enable the controller
   */
  void setEnabled(boolean enabled);

  /**
   * Gets whether the controller is enabled. This should return the last value passed to
   * {@link #setEnabled}.
   *
   * @return whether the controller is enabled.
   */
  boolean isEnabled();

  /**
   * Sets the listener for the controller to call back when the matrix changes.
   *
   * @param listener the listener
   */
  void setListener(Listener listener);

  /**
   * Gets the current scale factor. A convenience method for calculating the scale from the
   * transform.
   *
   * @return the current scale factor
   */
  float getScaleFactor();

  /**
   * Gets the current transform.
   *
   * @return the transform
   */
  Matrix getTransform();

  /**
   * Sets the bounds of the image post transform prior to application of the zoomable
   * transformation.
   *
   * @param imageBounds the bounds of the image
   */
  void setImageBounds(RectF imageBounds);

  /**
   * Sets the bounds of the view.
   *
   * @param viewBounds the bounds of the view
   */
  void setViewBounds(RectF viewBounds);

  /**
   * Allows the controller to handle a touch event.
   *
   * @param event the touch event
   * @return whether the controller handled the event
   */
  boolean onTouchEvent(MotionEvent event);
}