Synnefo

/*

 * Copyright 2011 GRNET S.A. All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or

 * without modification, are permitted provided that the following

 * conditions are met:

 *

 *   1. Redistributions of source code must retain the above

 *      copyright notice, this list of conditions and the following

 *      disclaimer.

 *

 *   2. Redistributions in binary form must reproduce the above

 *      copyright notice, this list of conditions and the following

 *      disclaimer in the documentation and/or other materials

 *      provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS

 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR

 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF

 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED

 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN

 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

 * POSSIBILITY OF SUCH DAMAGE.

 *

 * The views and conclusions contained in the software and

 * documentation are those of the authors and should not be

 * interpreted as representing official policies, either expressed

 * or implied, of GRNET S.A.

 */

package gr.grnet.pithos.web.client;

import com.google.gwt.cell.client.Cell.Context;

import com.google.gwt.cell.client.ClickableTextCell;

import com.google.gwt.core.client.GWT;

import com.google.gwt.resources.client.ClientBundle;

import com.google.gwt.resources.client.ImageResource;

import com.google.gwt.safehtml.client.SafeHtmlTemplates;

import com.google.gwt.safehtml.shared.SafeHtml;

import com.google.gwt.safehtml.shared.SafeHtmlBuilder;

import com.google.gwt.safehtml.shared.SafeHtmlUtils;

import com.google.gwt.user.cellview.client.Header;

import com.google.gwt.user.client.ui.AbstractImagePrototype;

/**

 * A {@link Header} subclass that maintains sorting state and displays an icon

 * to indicate the sort direction.

 */

public class SortableHeader extends Header<String> {

  interface Template extends SafeHtmlTemplates {

    @Template("<div style=\"position:relative;cursor:hand;cursor:pointer;"

        + "padding-right:{0}px;\">{1}<div>{2}</div></div>")

    SafeHtml sorted(int imageWidth, SafeHtml arrow, String text);

    @Template("<div style=\"position:relative;cursor:hand;cursor:pointer;"

        + "padding-right:{0}px;\"><div style=\"position:absolute;display:none;"

        + "\"></div><div>{1}</div></div>")

    SafeHtml unsorted(int imageWidth, String text);

  }

  private static Template template;

  /**

   * Image resources.

   */

  public static interface Resources extends ClientBundle {

    ImageResource downArrow();

    ImageResource upArrow();

  }

  private static final Resources RESOURCES = GWT.create(Resources.class);

  private static final int IMAGE_WIDTH = 16;

  private static final SafeHtml DOWN_ARROW = makeImage(RESOURCES.downArrow());

  private static final SafeHtml UP_ARROW = makeImage(RESOURCES.upArrow());

  private static SafeHtml makeImage(ImageResource resource) {

    AbstractImagePrototype proto = AbstractImagePrototype.create(resource);

    String html = proto.getHTML().replace("style='",

        "style='position:absolute;right:0px;top:0px;");

    return SafeHtmlUtils.fromTrustedString(html);

  }

  private boolean reverseSort = false;

  private boolean sorted = false;

  private String text;

  SortableHeader(String text) {

    super(new ClickableTextCell());

    if (template == null) {

      template = GWT.create(Template.class);

    }

    this.text = text;

  }

  public boolean getReverseSort() {

    return reverseSort;

  }

  @Override

  public String getValue() {

    return text;

  }

  @Override

  public void render(@SuppressWarnings("unused") Context context, SafeHtmlBuilder sb) {

    if (sorted) {

      sb.append(template.sorted(IMAGE_WIDTH, reverseSort ? DOWN_ARROW : UP_ARROW, text));

    } else {

      sb.append(template.unsorted(IMAGE_WIDTH, text));

    }

  }

  public void setReverseSort(boolean reverseSort) {

    this.reverseSort = reverseSort;

  }

  public void setSorted(boolean sorted) {

    this.sorted = sorted;

  }

  public void toggleReverseSort() {

    this.reverseSort = !this.reverseSort;

  }

}