Copyright (c) 2006, 2011 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
    Benjamin Muskalla - fix for the console help text (bug 240607)
/*******************************************************************************
 * Copyright (c) 2006, 2011 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *     Benjamin Muskalla - fix for the console help text (bug 240607)
 *******************************************************************************/

package org.eclipse.core.internal.registry.osgi;

import org.eclipse.core.runtime.*;
import org.eclipse.osgi.framework.console.CommandInterpreter;
import org.eclipse.osgi.framework.console.CommandProvider;

public class RegistryCommandProvider implements CommandProvider {

	private final static String NEW_LINE = "\r\n"; //$NON-NLS-1$

	private static final String indent = "   "; //$NON-NLS-1$

	private boolean verbose = false; // is command run in a "verbose" mode?

	@Override
	public String getHelp() {
		return getHelp(null);
	}

	/*
	 * This method either returns the help message for a particular command,
	 * or returns the help messages for all commands (if commandName is null)
	 */
	private String getHelp(String commandName) {
		boolean all = commandName == null;
		StringBuilder sb = new StringBuilder();
		if (all) {
			sb.append("---Extension Registry Commands---"); //$NON-NLS-1$
			sb.append(NEW_LINE);
		}
		if (all || "ns".equals(commandName)) { //$NON-NLS-1$
			sb.append("\tns [-v] [name] - display extension points in the namespace; add -v to display extensions"); //$NON-NLS-1$
			sb.append(NEW_LINE);
		}
		if (all || "pt".equals(commandName)) { //$NON-NLS-1$
			sb.append("\tpt [-v] uniqueExtensionPointId - display the extension point and extensions; add -v to display config elements"); //$NON-NLS-1$
			sb.append(NEW_LINE);
		}
		return sb.toString();
	}

	public void _ns(CommandInterpreter ci) throws Exception {
		String namespace = getArgument(ci);
		if (namespace == null) {
			String[] namespaces = RegistryFactory.getRegistry().getNamespaces();
			ci.println("Namespace(s):"); //$NON-NLS-1$
			ci.println("-------------------"); //$NON-NLS-1$
			for (String n : namespaces) {
				ci.println(n);
			}
			return;
		}

		IExtensionRegistry registry = RegistryFactory.getRegistry();
		IExtensionPoint[] extpts = registry.getExtensionPoints(namespace);
		ci.println("Extension point(s):"); //$NON-NLS-1$
		ci.println("-------------------"); //$NON-NLS-1$
		for (IExtensionPoint extpt : extpts) {
			displayExtensionPoint(extpt, ci);
		}

		if (verbose) {
			ci.println("\nExtension(s):"); //$NON-NLS-1$
			ci.println("-------------------"); //$NON-NLS-1$
			IExtension[] exts = RegistryFactory.getRegistry().getExtensions(namespace);
			for (IExtension ext : exts) {
				displayExtension(ext, ci, true /*full*/);
			}
		}
	}

	public void _pt(CommandInterpreter ci) throws Exception {
		String extensionPointId = getArgument(ci);
		if (extensionPointId == null)
			return;
		IExtensionPoint extpt = RegistryFactory.getRegistry().getExtensionPoint(extensionPointId);
		if (extpt == null)
			return;
		ci.print("Extension point: "); //$NON-NLS-1$
		displayExtensionPoint(extpt, ci);
		IExtension[] exts = extpt.getExtensions();
		ci.println("\nExtension(s):"); //$NON-NLS-1$
		ci.println("-------------------"); //$NON-NLS-1$
		for (IExtension ext : exts) {
			displayExtension(ext, ci, false /*short*/);
			if (verbose) {
				IConfigurationElement[] ce = ext.getConfigurationElements();
				for (IConfigurationElement ce1 : ce) {
					displayConfigElement(ci, ce1, 1);
				}
				ci.println();
			}
		}
	}

	
Handles the help command
Params:
intp – 
Returns:
description for a particular command or false if there is no command with the specified name/**
	 * Handles the help command
	 *
	 * @param intp
	 * @return description for a particular command or false if there is no command with the specified name
	 */
	public Object _help(CommandInterpreter intp) {
		String commandName = intp.nextArgument();
		if (commandName == null) {
			return Boolean.FALSE;
		}
		String help = getHelp(commandName);

		if (help.length() > 0) {
			return help;
		}

		return Boolean.FALSE;
	}

	// This method has a side effect of setting the verbose flag
	private String getArgument(CommandInterpreter ci) {
		String firstParm = ci.nextArgument();
		if ("-v".equals(firstParm)) { //$NON-NLS-1$
			verbose = true;
			return ci.nextArgument();
		}

		verbose = false;
		return firstParm;
	}

	private void displayExtensionPoint(IExtensionPoint extentionPoint, CommandInterpreter ci) {
		if (extentionPoint == null)
			return;
		ci.println(extentionPoint.getUniqueIdentifier() + " [from " + extentionPoint.getContributor().getName() + ']'); //$NON-NLS-1$
	}

	private void displayExtension(IExtension extention, CommandInterpreter ci, boolean full) {
		if (extention == null)
			return;
		if (full) {
			ci.print("Id: " + extention.getUniqueIdentifier()); //$NON-NLS-1$
			ci.print(" PointId: " + extention.getExtensionPointUniqueIdentifier()); //$NON-NLS-1$
			ci.println(" [from " + extention.getContributor().getName() + "]"); //$NON-NLS-1$ //$NON-NLS-2$
		} else {
			ci.println(extention.getUniqueIdentifier() + " [from " + extention.getContributor().getName() + "]"); //$NON-NLS-1$ //$NON-NLS-2$
		}
	}

	private void displayConfigElement(CommandInterpreter ci, IConfigurationElement ce, int level) throws Exception {
		String spacing = spacing(ci, level);
		ci.println(spacing + '<' + ce.getName() + '>');
		String[] attrs = ce.getAttributeNames();
		for (String attr : attrs) {
			ci.println(indent + spacing + attr + " = " + ce.getAttribute(attr)); //$NON-NLS-1$
		}
		String value = ce.getValue();
		if (value != null)
			ci.println(indent + spacing + value);
		IConfigurationElement[] children = ce.getChildren();
		for (IConfigurationElement child : children) {
			displayConfigElement(ci, child, level + 1);
		}
		ci.println(spacing + "</" + ce.getName() + '>'); //$NON-NLS-1$
	}

	private String spacing(CommandInterpreter ci, int level) {
		StringBuilder b = new StringBuilder();
		for (int i = 0; i < level; i++)
			b.append(indent);
		return b.toString();
	}
}