content: /*******************************************************************************
   * Copyright (c) 2000, 2008 IBM Corporation and others.
   * All rights reserved. This program and the accompanying materials
   * are made available under the terms of the Eclipse Public License v1.0
   * which accompanies this distribution, and is available at
   * http://www.eclipse.org/legal/epl-v10.html
   *
   * Contributors:
   *     IBM Corporation - initial API and implementation
   *******************************************************************************/
  package org.eclipse.wst.jsdt.ui.actions;
  
  import java.lang.reflect.InvocationTargetException;
  import java.net.URL;
  
  import org.eclipse.core.runtime.CoreException;
  import org.eclipse.jface.dialogs.MessageDialog;
  import org.eclipse.jface.text.ITextSelection;
  import org.eclipse.jface.viewers.IStructuredSelection;
  import org.eclipse.swt.widgets.Display;
  import org.eclipse.swt.widgets.Shell;
  import org.eclipse.ui.IWorkbenchSite;
  import org.eclipse.ui.PlatformUI;
  import org.eclipse.wst.jsdt.core.IJavaScriptElement;
  import org.eclipse.wst.jsdt.core.IPackageFragmentRoot;
  import org.eclipse.wst.jsdt.internal.corext.util.JavaModelUtil;
  import org.eclipse.wst.jsdt.internal.corext.util.Messages;
  import org.eclipse.wst.jsdt.internal.ui.IJavaHelpContextIds;
  import org.eclipse.wst.jsdt.internal.ui.JavaScriptPlugin;
  import org.eclipse.wst.jsdt.internal.ui.actions.ActionMessages;
  import org.eclipse.wst.jsdt.internal.ui.actions.ActionUtil;
  import org.eclipse.wst.jsdt.internal.ui.actions.OpenBrowserUtil;
  import org.eclipse.wst.jsdt.internal.ui.actions.SelectionConverter;
  import org.eclipse.wst.jsdt.internal.ui.javaeditor.JavaEditor;
  import org.eclipse.wst.jsdt.internal.ui.util.ExceptionHandler;
  import org.eclipse.wst.jsdt.ui.JavaScriptElementLabels;
  import org.eclipse.wst.jsdt.ui.JavaScriptUI;
  
  /**
   * This action opens the selected element's Javadoc in an external 
   * browser. 
   * <p>
   * The action is applicable to selections containing elements of 
   * type <code>IJavaScriptElement</code>.
   * 
   * <p>
   * This class may be instantiated; it is not intended to be subclassed.
   * </p>
   * 
   *
   * Provisional API: This class/interface is part of an interim API that is still under development and expected to
   * change significantly before reaching stability. It is being made available at this early stage to solicit feedback
   * from pioneering adopters on the understanding that any code that uses this API will almost certainly be broken
   * (repeatedly) as the API evolves.
   */
  public class OpenExternalJavadocAction extends SelectionDispatchAction {
  		
  	private JavaEditor fEditor;
  	
  	/**
  	 * Creates a new <code>OpenExternalJavadocAction</code>. The action requires
  	 * that the selection provided by the site's selection provider is of type <code>
  	 * org.eclipse.jface.viewers.IStructuredSelection</code>.
  	 * 
  	 * @param site the site providing additional context information for this action
  	 */ 
  	public OpenExternalJavadocAction(IWorkbenchSite site) {
  		super(site);
  		setText(ActionMessages.OpenExternalJavadocAction_label); 
  		setDescription(ActionMessages.OpenExternalJavadocAction_description); 
  		setToolTipText(ActionMessages.OpenExternalJavadocAction_tooltip); 
  		PlatformUI.getWorkbench().getHelpSystem().setHelp(this, IJavaHelpContextIds.OPEN_EXTERNAL_JAVADOC_ACTION);
  	}
  	
  
  	
  	/**
  	 * Note: This constructor is for internal use only. Clients should not call this constructor.
  	 * @param editor the JavaScript editor
  	 */
  	public OpenExternalJavadocAction(JavaEditor editor) {
  		this(editor.getEditorSite());
  		fEditor= editor;
  		setEnabled(SelectionConverter.canOperateOn(fEditor));
  	}
  	
  	/* (non-Javadoc)
  	 * Method declared on SelectionDispatchAction.
  	 */
  	public void selectionChanged(ITextSelection selection) {
  	}
  
  	/* (non-Javadoc)
  	 * Method declared on SelectionDispatchAction.
  	 */
  	public void selectionChanged(IStructuredSelection selection) {
  		setEnabled(checkEnabled(selection));
  	}
  	
  	private boolean checkEnabled(IStructuredSelection selection) {
  		if (selection.size() != 1)
  			return false;
  		return selection.getFirstElement() instanceof IJavaScriptElement;
  	}
  	
  	/* (non-Javadoc)
  	 * Method declared on SelectionDispatchAction.
  	 */
  	public void run(ITextSelection selection) {
  		IJavaScriptElement element= SelectionConverter.getInput(fEditor);
  		if (!ActionUtil.isProcessable(getShell(), element))
  			return;
  		
  		try {
  			IJavaScriptElement[] elements= SelectionConverter.codeResolveOrInputForked(fEditor);
  			if (elements == null || elements.length == 0)
  				return;
  			IJavaScriptElement candidate= elements[0];
  			if (elements.length > 1) {
  				candidate= SelectionConverter.selectJavaElement(elements, getShell(), getDialogTitle(), ActionMessages.OpenExternalJavadocAction_select_element);
  			}
  			if (candidate != null) {
  				run(candidate);
  			}
  		} catch (InvocationTargetException e) {
  			ExceptionHandler.handle(e, getShell(), getDialogTitle(), ActionMessages.OpenExternalJavadocAction_code_resolve_failed); 
  		} catch (InterruptedException e) {
  			// cancelled
  		}
  	}
  	
  	/* (non-Javadoc)
  	 * Method declared on SelectionDispatchAction.
  	 */
  	public void run(IStructuredSelection selection) {
  		if (!checkEnabled(selection))
  			return;
  		IJavaScriptElement element= (IJavaScriptElement)selection.getFirstElement();
  		if (!ActionUtil.isProcessable(getShell(), element))
  			return;			
  		run(element);
  	}
  	
  	/*
  	 * No Javadoc since the method isn't meant to be public but is
  	 * since the beginning
  	 */
  	public void run(IJavaScriptElement element) {
  		if (element == null)
  			return;
  		Shell shell= getShell();
  		try {
  			String labelName= JavaScriptElementLabels.getElementLabel(element, JavaScriptElementLabels.ALL_DEFAULT);
  			
  			URL baseURL= JavaScriptUI.getJSdocBaseLocation(element);
  			if (baseURL == null) {
  				IPackageFragmentRoot root= JavaModelUtil.getPackageFragmentRoot(element);
  				if (root != null && root.getKind() == IPackageFragmentRoot.K_BINARY) {
  					String message= ActionMessages.OpenExternalJavadocAction_libraries_no_location;	 
  					showMessage(shell, Messages.format(message, new String[] { labelName, root.getElementName() }), false);
  				} else {
  					IJavaScriptElement annotatedElement= element.getJavaScriptProject();
  					String message= ActionMessages.OpenExternalJavadocAction_source_no_location;	 
  					showMessage(shell, Messages.format(message, new String[] { labelName, annotatedElement.getElementName() }), false);
  				}
  				return;
  			}		
  			URL url= JavaScriptUI.getJSdocLocation(element, true);
  			if (url != null) {
  				OpenBrowserUtil.open(url, shell.getDisplay(), getTitle());
  			} 		
  		} catch (CoreException e) {
  			JavaScriptPlugin.log(e);
  			showMessage(shell, ActionMessages.OpenExternalJavadocAction_opening_failed, true); 
  		}
  	}
  	
  	private static void showMessage(final Shell shell, final String message, final boolean isError) {
  		Display.getDefault().asyncExec(new Runnable() {
  			public void run() {
  				if (isError) {
  					MessageDialog.openError(shell, getTitle(), message); 
  				} else {
  					MessageDialog.openInformation(shell, getTitle(), message); 
  				}
  			}
  		});
  	}
  	
  	private static String getTitle() {
  		return ActionMessages.OpenExternalJavadocAction_dialog_title; 
  	}
  	
  	/**
  	 * Note: this method is for internal use only. Clients should not call this method.
  	 * 
  	 * @return the dialog default title
  	 */
  	protected String getDialogTitle() {
  		return getTitle();
  	}	
  }
  