package openworkspace.actions;

import org.eclipse.jface.action.IAction;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.swt.widgets.DirectoryDialog;
import org.eclipse.ui.IWorkbenchWindow;
import org.eclipse.ui.IWorkbenchWindowActionDelegate;

/**
 * Our sample action implements workbench action delegate.
 * The action proxy will be created by the workbench and
 * shown in the UI. When the user tries to use the action,
 * this delegate will be created and execution will be 
 * delegated to it.
 * @see IWorkbenchWindowActionDelegate
 */
public class SampleAction implements IWorkbenchWindowActionDelegate {
	private IWorkbenchWindow window;

	private static final String PROP_VM = "eclipse.vm"; //$NON-NLS-1$
	private static final String PROP_VMARGS = "eclipse.vmargs"; //$NON-NLS-1$
	private static final String PROP_COMMANDS = "eclipse.commands"; //$NON-NLS-1$
/**
	 * The constructor.
	 */
	public SampleAction() {
	}

	/**
	 * The action has been activated. The argument of the
	 * method represents the 'real' action sitting
	 * in the workbench UI.
	 * @see IWorkbenchWindowActionDelegate#run
	 */
	public void run(IAction action) {
		String path = new DirectoryDialog(window.getShell()).open();
		if (path == null)
			return;
		String command = buildCommandLine("-data", path);
		System.setProperty("eclipse.exitcode", Integer.toString(24));
		System.setProperty("eclipse.exitdata", command);
		window.getWorkbench().restart();
	}

	private String buildCommandLine(String arg, String value) {
		StringBuffer result = new StringBuffer(300);
		String entry = System.getProperty(PROP_VM);
		if (entry == null)
			return null;
		result.append(entry );
		result.append('\n');
		// append the vmargs and commands.  Assume that these already end in \n
		entry = System.getProperty(PROP_VMARGS);
		if (entry != null) 
			result.append(entry);
		entry = System.getProperty(PROP_COMMANDS);
		if (entry != null) {
			entry = "\n" + entry;
			int i = entry.indexOf("\n" + arg + "\n");
			if (i == -1)
				entry = arg + "\n" + value + entry;
			else {
				i += arg.length() + 2;
				// skip the leading \n
				String left = entry.substring(1, i);
				int j = entry.indexOf('\n', i);
				String right = entry.substring(j);
				entry = left + value + right;
			}
			result.append(entry);
		}
		return result.toString();
	}

	/**
	 * Selection in the workbench has been changed. We 
	 * can change the state of the 'real' action here
	 * if we want, but this can only happen after 
	 * the delegate has been created.
	 * @see IWorkbenchWindowActionDelegate#selectionChanged
	 */
	public void selectionChanged(IAction action, ISelection selection) {
	}

	/**
	 * We can use this method to dispose of any system
	 * resources we previously allocated.
	 * @see IWorkbenchWindowActionDelegate#dispose
	 */
	public void dispose() {
	}

	/**
	 * We will cache window object in order to
	 * be able to provide parent shell for the message dialog.
	 * @see IWorkbenchWindowActionDelegate#init
	 */
	public void init(IWorkbenchWindow window) {
		this.window = window;
	}
}