package org.codehaus.plexus.util.cli;

/*
 * Copyright The Codehaus Foundation.
 *
 * Licensed 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.
 */

import java.io.IOException;
import java.io.InputStream;
import java.util.Locale;
import java.util.Map;
import java.util.Properties;
import java.util.StringTokenizer;
import java.util.Vector;

import org.codehaus.plexus.util.Os;
import org.codehaus.plexus.util.StringUtils;

Author:
Trygve Laugstøl 
Version:
$Id$/**
 * @author <a href="mailto:trygvis@inamo.no">Trygve Laugst&oslash;l </a>
 * @version $Id$
 */
public abstract class CommandLineUtils
{

    
A StreamConsumer providing consumed lines as a String. 
See Also:
getOutput()/**
     * A {@code StreamConsumer} providing consumed lines as a {@code String}.
     *
     * @see #getOutput()
     */
    public static class StringStreamConsumer
        implements StreamConsumer
    {

        private StringBuffer string = new StringBuffer();

        private String ls = System.getProperty( "line.separator" );

        public void consumeLine( String line )
        {
            string.append( line ).append( ls );
        }

        public String getOutput()
        {
            return string.toString();
        }

    }

    
Number of milliseconds per second.
/**
     * Number of milliseconds per second.
     */
    private static final long MILLIS_PER_SECOND = 1000L;

    
Number of nanoseconds per second.
/**
     * Number of nanoseconds per second.
     */
    private static final long NANOS_PER_SECOND = 1000000000L;

    public static int executeCommandLine( Commandline cl, StreamConsumer systemOut, StreamConsumer systemErr )
        throws CommandLineException
    {
        return executeCommandLine( cl, null, systemOut, systemErr, 0 );
    }

    public static int executeCommandLine( Commandline cl, StreamConsumer systemOut, StreamConsumer systemErr,
                                          int timeoutInSeconds )
        throws CommandLineException
    {
        return executeCommandLine( cl, null, systemOut, systemErr, timeoutInSeconds );
    }

    public static int executeCommandLine( Commandline cl, InputStream systemIn, StreamConsumer systemOut,
                                          StreamConsumer systemErr )
        throws CommandLineException
    {
        return executeCommandLine( cl, systemIn, systemOut, systemErr, 0 );
    }

    
Params:
cl – The command line to execute
systemIn – The input to read from, must be thread safe
systemOut – A consumer that receives output, must be thread safe
systemErr – A consumer that receives system error stream output, must be thread safe
timeoutInSeconds – Positive integer to specify timeout, zero and negative integers for no timeout.
Throws:
CommandLineException – or CommandLineTimeOutException if time out occurs
Returns:
A return value, see Process.exitValue()/**
     * @param cl The command line to execute
     * @param systemIn The input to read from, must be thread safe
     * @param systemOut A consumer that receives output, must be thread safe
     * @param systemErr A consumer that receives system error stream output, must be thread safe
     * @param timeoutInSeconds Positive integer to specify timeout, zero and negative integers for no timeout.
     * @return A return value, see {@link Process#exitValue()}
     * @throws CommandLineException or CommandLineTimeOutException if time out occurs
     */
    public static int executeCommandLine( Commandline cl, InputStream systemIn, StreamConsumer systemOut,
                                          StreamConsumer systemErr, int timeoutInSeconds )
        throws CommandLineException
    {
        final CommandLineCallable future =
            executeCommandLineAsCallable( cl, systemIn, systemOut, systemErr, timeoutInSeconds );
        return future.call();
    }

    
Immediately forks a process, returns a callable that will block until process is complete.
Params:
cl – The command line to execute
systemIn – The input to read from, must be thread safe
systemOut – A consumer that receives output, must be thread safe
systemErr – A consumer that receives system error stream output, must be thread safe
timeoutInSeconds – Positive integer to specify timeout, zero and negative integers for no timeout.
Throws:
CommandLineException – or CommandLineTimeOutException if time out occurs
Returns:
A CommandLineCallable that provides the process return value, see Process.exitValue(). "call" must be called on this to be sure the forked process has terminated, no guarantees is made about any internal state before after the completion of the call statements/**
     * Immediately forks a process, returns a callable that will block until process is complete.
     * 
     * @param cl The command line to execute
     * @param systemIn The input to read from, must be thread safe
     * @param systemOut A consumer that receives output, must be thread safe
     * @param systemErr A consumer that receives system error stream output, must be thread safe
     * @param timeoutInSeconds Positive integer to specify timeout, zero and negative integers for no timeout.
     * @return A CommandLineCallable that provides the process return value, see {@link Process#exitValue()}. "call"
     *         must be called on this to be sure the forked process has terminated, no guarantees is made about any
     *         internal state before after the completion of the call statements
     * @throws CommandLineException or CommandLineTimeOutException if time out occurs
     */
    public static CommandLineCallable executeCommandLineAsCallable( final Commandline cl, final InputStream systemIn,
                                                                    final StreamConsumer systemOut,
                                                                    final StreamConsumer systemErr,
                                                                    final int timeoutInSeconds )
        throws CommandLineException
    {
        if ( cl == null )
        {
            throw new IllegalArgumentException( "cl cannot be null." );
        }

        final Process p = cl.execute();

        final Thread processHook = new Thread()
        {

            {
                this.setName( "CommandLineUtils process shutdown hook" );
                this.setContextClassLoader( null );
            }

            @Override
            public void run()
            {
                p.destroy();
            }

        };

        ShutdownHookUtils.addShutDownHook( processHook );

        return new CommandLineCallable()
        {

            public Integer call()
                throws CommandLineException
            {
                StreamFeeder inputFeeder = null;
                StreamPumper outputPumper = null;
                StreamPumper errorPumper = null;
                boolean success = false;
                try
                {
                    if ( systemIn != null )
                    {
                        inputFeeder = new StreamFeeder( systemIn, p.getOutputStream() );
                        inputFeeder.start();
                    }

                    outputPumper = new StreamPumper( p.getInputStream(), systemOut );
                    outputPumper.start();

                    errorPumper = new StreamPumper( p.getErrorStream(), systemErr );
                    errorPumper.start();

                    int returnValue;
                    if ( timeoutInSeconds <= 0 )
                    {
                        returnValue = p.waitFor();
                    }
                    else
                    {
                        final long now = System.nanoTime();
                        final long timeout = now + NANOS_PER_SECOND * timeoutInSeconds;

                        while ( isAlive( p ) && ( System.nanoTime() < timeout ) )
                        {
                            // The timeout is specified in seconds. Therefore we must not sleep longer than one second
                            // but we should sleep as long as possible to reduce the number of iterations performed.
                            Thread.sleep( MILLIS_PER_SECOND - 1L );
                        }

                        if ( isAlive( p ) )
                        {
                            throw new InterruptedException( String.format( "Process timed out after %d seconds.",
                                                                           timeoutInSeconds ) );
                        }

                        returnValue = p.exitValue();
                    }

                    // TODO Find out if waitUntilDone needs to be called using a try-finally construct. The method may
                    // throw an
                    // InterruptedException so that calls to waitUntilDone may be skipped.
                    // try
                    // {
                    // if ( inputFeeder != null )
                    // {
                    // inputFeeder.waitUntilDone();
                    // }
                    // }
                    // finally
                    // {
                    // try
                    // {
                    // outputPumper.waitUntilDone();
                    // }
                    // finally
                    // {
                    // errorPumper.waitUntilDone();
                    // }
                    // }
                    if ( inputFeeder != null )
                    {
                        inputFeeder.waitUntilDone();
                    }

                    outputPumper.waitUntilDone();
                    errorPumper.waitUntilDone();

                    if ( inputFeeder != null )
                    {
                        inputFeeder.close();
                        handleException( inputFeeder, "stdin" );
                    }

                    outputPumper.close();
                    handleException( outputPumper, "stdout" );

                    errorPumper.close();
                    handleException( errorPumper, "stderr" );

                    success = true;
                    return returnValue;
                }
                catch ( InterruptedException ex )
                {
                    throw new CommandLineTimeOutException( "Error while executing external command, process killed.",
                                                           ex );

                }
                finally
                {
                    if ( inputFeeder != null )
                    {
                        inputFeeder.disable();
                    }
                    if ( outputPumper != null )
                    {
                        outputPumper.disable();
                    }
                    if ( errorPumper != null )
                    {
                        errorPumper.disable();
                    }

                    try
                    {
                        ShutdownHookUtils.removeShutdownHook( processHook );
                        processHook.run();
                    }
                    finally
                    {
                        try
                        {
                            if ( inputFeeder != null )
                            {
                                inputFeeder.close();

                                if ( success )
                                {
                                    success = false;
                                    handleException( inputFeeder, "stdin" );
                                    success = true; // Only reached when no exception has been thrown.
                                }
                            }
                        }
                        finally
                        {
                            try
                            {
                                if ( outputPumper != null )
                                {
                                    outputPumper.close();

                                    if ( success )
                                    {
                                        success = false;
                                        handleException( outputPumper, "stdout" );
                                        success = true; // Only reached when no exception has been thrown.
                                    }
                                }
                            }
                            finally
                            {
                                if ( errorPumper != null )
                                {
                                    errorPumper.close();

                                    if ( success )
                                    {
                                        handleException( errorPumper, "stderr" );
                                    }
                                }
                            }
                        }
                    }
                }
            }

        };
    }

    private static void handleException( final StreamPumper streamPumper, final String streamName )
        throws CommandLineException
    {
        if ( streamPumper.getException() != null )
        {
            throw new CommandLineException( String.format( "Failure processing %s.", streamName ),
                                            streamPumper.getException() );

        }
    }

    private static void handleException( final StreamFeeder streamFeeder, final String streamName )
        throws CommandLineException
    {
        if ( streamFeeder.getException() != null )
        {
            throw new CommandLineException( String.format( "Failure processing %s.", streamName ),
                                            streamFeeder.getException() );

        }
    }

    
Gets the shell environment variables for this process. Note that the returned mapping from variable names to
values will always be case-sensitive regardless of the platform, i.e. getSystemEnvVars().get("path")
and getSystemEnvVars().get("PATH") will in general return different values. However, on platforms
with case-insensitive environment variables like Windows, all variable names will be normalized to upper case.
Throws:
IOException – If the environment variables could not be queried from the shell.
See Also:
System.getenv() API, new in JDK 5.0, to get the same result since 2.0.2 System#getenv()
     will be used if available in the current running jvm.
Returns:
The shell environment variables, can be empty but never null./**
     * Gets the shell environment variables for this process. Note that the returned mapping from variable names to
     * values will always be case-sensitive regardless of the platform, i.e. <code>getSystemEnvVars().get("path")</code>
     * and <code>getSystemEnvVars().get("PATH")</code> will in general return different values. However, on platforms
     * with case-insensitive environment variables like Windows, all variable names will be normalized to upper case.
     *
     * @return The shell environment variables, can be empty but never <code>null</code>.
     * @throws IOException If the environment variables could not be queried from the shell.
     * @see System#getenv() System.getenv() API, new in JDK 5.0, to get the same result <b>since 2.0.2 System#getenv()
     *      will be used if available in the current running jvm.</b>
     */
    public static Properties getSystemEnvVars()
        throws IOException
    {
        return getSystemEnvVars( !Os.isFamily( Os.FAMILY_WINDOWS ) );
    }

    
Return the shell environment variables. If caseSensitive == true, then envar keys will all be
upper-case.
Params:
caseSensitive – Whether environment variable keys should be treated case-sensitively.
Throws:
 IOException .
 – 
See Also:
System.getenv() API, new in JDK 5.0, to get the same result since 2.0.2 System#getenv()
     will be used if available in the current running jvm.
Returns:
Properties object of (possibly modified) envar keys mapped to their values./**
     * Return the shell environment variables. If <code>caseSensitive == true</code>, then envar keys will all be
     * upper-case.
     *
     * @param caseSensitive Whether environment variable keys should be treated case-sensitively.
     * @return Properties object of (possibly modified) envar keys mapped to their values.
     * @throws IOException .
     * @see System#getenv() System.getenv() API, new in JDK 5.0, to get the same result <b>since 2.0.2 System#getenv()
     *      will be used if available in the current running jvm.</b>
     */
    public static Properties getSystemEnvVars( boolean caseSensitive )
        throws IOException
    {
        Properties envVars = new Properties();
        Map<String, String> envs = System.getenv();
        for ( String key : envs.keySet() )
        {
            String value = envs.get( key );
            if ( !caseSensitive )
            {
                key = key.toUpperCase( Locale.ENGLISH );
            }
            envVars.put( key, value );
        }
        return envVars;
    }

    public static boolean isAlive( Process p )
    {
        if ( p == null )
        {
            return false;
        }

        try
        {
            p.exitValue();
            return false;
        }
        catch ( IllegalThreadStateException e )
        {
            return true;
        }
    }

    public static String[] translateCommandline( String toProcess )
        throws Exception
    {
        if ( ( toProcess == null ) || ( toProcess.length() == 0 ) )
        {
            return new String[0];
        }

        // parse with a simple finite state machine

        final int normal = 0;
        final int inQuote = 1;
        final int inDoubleQuote = 2;
        int state = normal;
        StringTokenizer tok = new StringTokenizer( toProcess, "\"\' ", true );
        Vector<String> v = new Vector<String>();
        StringBuilder current = new StringBuilder();

        while ( tok.hasMoreTokens() )
        {
            String nextTok = tok.nextToken();
            switch ( state )
            {
                case inQuote:
                    if ( "\'".equals( nextTok ) )
                    {
                        state = normal;
                    }
                    else
                    {
                        current.append( nextTok );
                    }
                    break;
                case inDoubleQuote:
                    if ( "\"".equals( nextTok ) )
                    {
                        state = normal;
                    }
                    else
                    {
                        current.append( nextTok );
                    }
                    break;
                default:
                    if ( "\'".equals( nextTok ) )
                    {
                        state = inQuote;
                    }
                    else if ( "\"".equals( nextTok ) )
                    {
                        state = inDoubleQuote;
                    }
                    else if ( " ".equals( nextTok ) )
                    {
                        if ( current.length() != 0 )
                        {
                            v.addElement( current.toString() );
                            current.setLength( 0 );
                        }
                    }
                    else
                    {
                        current.append( nextTok );
                    }
                    break;
            }
        }

        if ( current.length() != 0 )
        {
            v.addElement( current.toString() );
        }

        if ( ( state == inQuote ) || ( state == inDoubleQuote ) )
        {
            throw new CommandLineException( "unbalanced quotes in " + toProcess );
        }

        String[] args = new String[v.size()];
        v.copyInto( args );
        return args;
    }

    

Put quotes around the given String if necessary.


If the argument doesn't include spaces or quotes, return it as is. If it contains double quotes, use single
quotes - else surround the argument by double quotes.

Throws:
CommandLineException – if the argument contains both, single and double quotes.
Deprecated:
Use StringUtils.quoteAndEscape(String, char, char[], char[], char, boolean), StringUtils.quoteAndEscape(String, char, char[], char, boolean), or StringUtils.quoteAndEscape(String, char) instead./**
     * <p>
     * Put quotes around the given String if necessary.
     * </p>
     * <p>
     * If the argument doesn't include spaces or quotes, return it as is. If it contains double quotes, use single
     * quotes - else surround the argument by double quotes.
     * </p>
     *
     * @throws CommandLineException if the argument contains both, single and double quotes.
     * @deprecated Use {@link StringUtils#quoteAndEscape(String, char, char[], char[], char, boolean)},
     *             {@link StringUtils#quoteAndEscape(String, char, char[], char, boolean)}, or
     *             {@link StringUtils#quoteAndEscape(String, char)} instead.
     */
    @SuppressWarnings( { "JavaDoc", "deprecation" } )
    public static String quote( String argument )
        throws CommandLineException
    {
        return quote( argument, false, false, true );
    }

    

Put quotes around the given String if necessary.


If the argument doesn't include spaces or quotes, return it as is. If it contains double quotes, use single
quotes - else surround the argument by double quotes.

Throws:
CommandLineException – if the argument contains both, single and double quotes.
Deprecated:
Use StringUtils.quoteAndEscape(String, char, char[], char[], char, boolean), StringUtils.quoteAndEscape(String, char, char[], char, boolean), or StringUtils.quoteAndEscape(String, char) instead./**
     * <p>
     * Put quotes around the given String if necessary.
     * </p>
     * <p>
     * If the argument doesn't include spaces or quotes, return it as is. If it contains double quotes, use single
     * quotes - else surround the argument by double quotes.
     * </p>
     *
     * @throws CommandLineException if the argument contains both, single and double quotes.
     * @deprecated Use {@link StringUtils#quoteAndEscape(String, char, char[], char[], char, boolean)},
     *             {@link StringUtils#quoteAndEscape(String, char, char[], char, boolean)}, or
     *             {@link StringUtils#quoteAndEscape(String, char)} instead.
     */
    @SuppressWarnings( { "JavaDoc", "UnusedDeclaration", "deprecation" } )
    public static String quote( String argument, boolean wrapExistingQuotes )
        throws CommandLineException
    {
        return quote( argument, false, false, wrapExistingQuotes );
    }

    
Deprecated:
Use StringUtils.quoteAndEscape(String, char, char[], char[], char, boolean), StringUtils.quoteAndEscape(String, char, char[], char, boolean), or StringUtils.quoteAndEscape(String, char) instead./**
     * @deprecated Use {@link StringUtils#quoteAndEscape(String, char, char[], char[], char, boolean)},
     *             {@link StringUtils#quoteAndEscape(String, char, char[], char, boolean)}, or
     *             {@link StringUtils#quoteAndEscape(String, char)} instead.
     */
    @SuppressWarnings( { "JavaDoc" } )
    public static String quote( String argument, boolean escapeSingleQuotes, boolean escapeDoubleQuotes,
                                boolean wrapExistingQuotes )
        throws CommandLineException
    {
        if ( argument.contains( "\"" ) )
        {
            if ( argument.contains( "\'" ) )
            {
                throw new CommandLineException( "Can't handle single and double quotes in same argument" );
            }
            else
            {
                if ( escapeSingleQuotes )
                {
                    return "\\\'" + argument + "\\\'";
                }
                else if ( wrapExistingQuotes )
                {
                    return '\'' + argument + '\'';
                }
            }
        }
        else if ( argument.contains( "\'" ) )
        {
            if ( escapeDoubleQuotes )
            {
                return "\\\"" + argument + "\\\"";
            }
            else if ( wrapExistingQuotes )
            {
                return '\"' + argument + '\"';
            }
        }
        else if ( argument.contains( " " ) )
        {
            if ( escapeDoubleQuotes )
            {
                return "\\\"" + argument + "\\\"";
            }
            else
            {
                return '\"' + argument + '\"';
            }
        }

        return argument;
    }

    public static String toString( String[] line )
    {
        // empty path return empty string
        if ( ( line == null ) || ( line.length == 0 ) )
        {
            return "";
        }

        // path containing one or more elements
        final StringBuilder result = new StringBuilder();
        for ( int i = 0; i < line.length; i++ )
        {
            if ( i > 0 )
            {
                result.append( ' ' );
            }
            try
            {
                result.append( StringUtils.quoteAndEscape( line[i], '\"' ) );
            }
            catch ( Exception e )
            {
                System.err.println( "Error quoting argument: " + e.getMessage() );
            }
        }
        return result.toString();
    }

}