/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.karaf.shell.impl.console.commands.help;
import java.io.PrintStream;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.felix.utils.properties.InterpolationHelper;
import org.apache.karaf.shell.api.console.Command;
import org.apache.karaf.shell.api.console.CommandLine;
import org.apache.karaf.shell.api.console.Completer;
import org.apache.karaf.shell.api.console.Registry;
import org.apache.karaf.shell.api.console.Session;
import org.apache.karaf.shell.api.console.SessionFactory;
import org.apache.karaf.shell.support.CommandException;
import org.apache.karaf.shell.support.completers.ArgumentCommandLine;
import org.apache.karaf.shell.support.completers.StringsCompleter;
import static org.apache.karaf.shell.support.ansi.SimpleAnsi.COLOR_DEFAULT;
import static org.apache.karaf.shell.support.ansi.SimpleAnsi.COLOR_RED;
import static org.apache.karaf.shell.support.ansi.SimpleAnsi.INTENSITY_BOLD;
import static org.apache.karaf.shell.support.ansi.SimpleAnsi.INTENSITY_NORMAL;
public class HelpCommand implements Command {
public HelpCommand(SessionFactory factory) {
Registry registry = factory.getRegistry();
registry.register(this);
registry.register(new SimpleHelpProvider());
registry.register(new CommandListHelpProvider());
registry.register(new SingleCommandHelpProvider());
}
@Override
public String getScope() {
return Session.SCOPE_GLOBAL;
}
@Override
public String getName() {
return "help";
}
@Override
public String getDescription() {
return "Displays this help or help about a command";
}
@Override
public Object execute(Session session, List<Object> arguments) throws Exception {
if (arguments.contains("--help")) {
printHelp(System.out);
return null;
}
if (arguments.size() > 1) {
String msg = COLOR_RED
+ "Error executing command "
+ INTENSITY_BOLD + getName() + INTENSITY_NORMAL
+ COLOR_DEFAULT + ": " + "too many arguments specified";
throw new CommandException(msg);
}
String path = arguments.isEmpty() ? null : arguments.get(0) == null ? null : arguments.get(0).toString();
String help = getHelp(session, path);
if (help != null) {
System.out.println(help);
}
return null;
}
@Override
public Completer getCompleter(final boolean scoped) {
return new Completer() {
@Override
public int complete(Session session, CommandLine commandLine, List<String> candidates) {
String[] args = commandLine.getArguments();
int argIndex = commandLine.getCursorArgumentIndex();
StringsCompleter completer = new StringsCompleter(Collections.singletonList(getName()));
if (argIndex == 0) {
return completer.complete(session, new ArgumentCommandLine(args[argIndex], commandLine.getArgumentPosition()), candidates);
} else if (!verifyCompleter(session, completer, args[0])) {
return -1;
}
// TODO: use CommandNamesCompleter and better completion wrt parsing etc...
completer = new StringsCompleter();
for (Command command : session.getRegistry().getCommands()) {
if (!Session.SCOPE_GLOBAL.equals(command.getScope())) {
completer.getStrings().add(command.getScope() + ":" + command.getName());
}
completer.getStrings().add(command.getName());
}
completer.getStrings().add("--help");
if (argIndex == 1) {
int res;
if (argIndex < args.length) {
res = completer.complete(session, new ArgumentCommandLine(args[argIndex], commandLine.getArgumentPosition()), candidates);
} else {
res = completer.complete(session, new ArgumentCommandLine("", 0), candidates);
}
return res + (commandLine.getBufferPosition() - commandLine.getArgumentPosition());
} else if (!verifyCompleter(session, completer, args[1])) {
return -1;
}
return -1;
}
protected boolean verifyCompleter(Session session, Completer completer, String argument) {
List<String> candidates = new ArrayList<String>();
return completer.complete(session, new ArgumentCommandLine(argument, argument.length()), candidates) != -1 && !candidates.isEmpty();
}
};
}
protected void printHelp(PrintStream out) {
out.println(INTENSITY_BOLD + "DESCRIPTION" + INTENSITY_NORMAL);
out.print(" ");
out.println(INTENSITY_BOLD + getName() + INTENSITY_NORMAL);
out.println();
out.print("\t");
out.println(getDescription());
out.println();
out.println(INTENSITY_BOLD + "SYNTAX" + INTENSITY_NORMAL);
out.print(" ");
out.println(getName() + " [options] [command]");
out.println();
out.println(INTENSITY_BOLD + "ARGUMENTS" + INTENSITY_NORMAL);
out.print(" ");
out.println(INTENSITY_BOLD + "command" + INTENSITY_NORMAL);
out.print(" ");
out.println("Command to display help for");
out.println();
out.println(INTENSITY_BOLD + "OPTIONS" + INTENSITY_NORMAL);
out.print(" ");
out.println(INTENSITY_BOLD + "--help" + INTENSITY_NORMAL);
out.print(" ");
out.println("Display this help message");
out.println();
}
public String getHelp(final Session session, String path) {
if (path == null) {
path = "%root%";
}
Map<String,String> props = new HashMap<String,String>();
props.put("data", "${" + path + "}");
final List<HelpProvider> providers = session.getRegistry().getServices(HelpProvider.class);
InterpolationHelper.performSubstitution(props, new InterpolationHelper.SubstitutionCallback() {
public String getValue(final String key) {
for (HelpProvider hp : providers) {
String result = hp.getHelp(session, key);
if (result != null) {
return removeNewLine(result);
}
}
return null;
}
});
return props.get("data");
}
private String removeNewLine(String help) {
if (help != null && help.endsWith("\n")) {
help = help.substring(0, help.length() -1);
}
return help;
}
}