/**********************************************
    * Copyright (C) 2009 Lukas Laag
    * This file is part of lib-gwt-svg-samples.
    * 
    * libgwtsvg-samples is free software: you can redistribute it and/or modify
    * it under the terms of the GNU General Public License as published by
    * the Free Software Foundation, either version 3 of the License, or
    * (at your option) any later version.
    * 
   * libgwtsvg-samples is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   * 
   * You should have received a copy of the GNU General Public License
   * along with libgwtsvg-samples.  If not, see http://www.gnu.org/licenses/
   **********************************************/
  package org.vectomatic.svg.samples.client;
  
  import com.google.gwt.core.client.GWT;
  import com.google.gwt.http.client.Request;
  import com.google.gwt.http.client.RequestBuilder;
  import com.google.gwt.http.client.RequestCallback;
  import com.google.gwt.http.client.RequestException;
  import com.google.gwt.http.client.Response;
  import com.google.gwt.uibinder.client.UiField;
  import com.google.gwt.user.client.ui.FlowPanel;
  import com.google.gwt.user.client.ui.HTML;
  import com.google.gwt.user.client.ui.Label;
  import com.google.gwt.user.client.ui.SimplePanel;
  import com.google.gwt.user.client.ui.TabLayoutPanel;
  
  /**
   * Base class for lib-gwt-svg samples. All samples are
   * stored in a tab panel with three tabs.
   * <ol>
   * <li>The first tab contains the result of the sample code execution</li>
   * <li>The second tab contains the source code for the sample</li>
   * <li>The third tab contains the UiBinder code for the sample</li>
   * <ol>
   * @author laaglu
   */
  public abstract class SampleBase {
  	/**
  	 * Directory where HTML-ified source code is generated
  	 */
  	public static final String HTML_SRC_DIR = "src/";
  	/**
  	 * Directory where HTML-ified UiBinder code is generated
  	 */
  	public static final String UIBINDER_SRC_DIR = "binder/";
  	/**
  	 * The HTML-ified source code
  	 */
  	public HTML sourceHtml;
  	/**
  	 * The HTML-ified UiBinder code
  	 */
  	public HTML uiBinderHtml;
  	/**
  	 * The tab panel containing this sample
  	 */
  	@UiField
  	public TabLayoutPanel tabPanel;
  
  	/**
  	 * Instantiates the tab panel which contains the sample
  	 * @return
  	 */
  	public abstract TabLayoutPanel getPanel();
  	
  	/**
  	 * Dynamically create the source code tab and UiBinder code tab
  	 * @param sampleName The name of the sample
  	 */
  	protected void createCodeTabs(String sampleName) {
  		sourceHtml = createCodeTab("HTML");
  		requestCodeContents(HTML_SRC_DIR + sampleName + ".html", sourceHtml);
  
  		uiBinderHtml = createCodeTab("UIBinder");
  		requestCodeContents(UIBINDER_SRC_DIR + sampleName + ".html", uiBinderHtml);
  
  		tabPanel.selectTab(0);
  	}
  	
  	private HTML createCodeTab(String tabName) {
  		// Create the tab container structure
  		FlowPanel tabContainer = new FlowPanel();
  		SimplePanel simplePanel = new SimplePanel();
  		FlowPanel container = new FlowPanel();
  		container.setStyleName(Main.mainBundle.css().sample());
  		HTML html = new HTML();
  		tabContainer.add(simplePanel);
  		simplePanel.setWidget(container);
  		container.add(html);
  		
  		// Create the tab item
  		Label label = new Label(tabName);
  		label.setStyleName(Main.mainBundle.css().tab());
 		
 		// Add the tab
 		tabPanel.add(tabContainer, label);
 		return html;
 	}
 
 	/**
 	 * Load the sample HTML source code
 	 */
 	protected void requestCodeContents(String partialPath, final HTML html) {
 
 		// Request the contents of the file
 		// Add a bogus query to bypass the browser cache as advised by:
 		// https://developer.mozilla.org/En/Using_XMLHttpRequest#Bypassing_the_cache
 		RequestBuilder builder = new RequestBuilder(RequestBuilder.GET, GWT.getModuleBaseURL() + partialPath + "?ts=" + System.currentTimeMillis());
 		builder.setCallback(new RequestCallback() {
 			public void onError(Request request, Throwable exception) {
 				html.setHTML("Cannot find resource");
 			}
 
 			public void onResponseReceived(Request request, Response response) {
 				html.setHTML(response.getText());
 			}
 		});
 
 		// Send the request
 		try {
 			builder.send();
 		} catch (RequestException e) {
 			GWT.log("Cannot fetch HTML source for " + partialPath, e);
 		}
 	}
 	/**
 	 * Resizes the sample
 	 */
 	protected void resize(int width, int height) {
 		GWT.log("resize: " + width + " " + height);
 	}
 }