package org.apache.maven.shared.utils.cli.shell;

/*
 * 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.
 */


import java.util.ArrayList;
import java.util.List;
import org.apache.maven.shared.utils.Os;
import org.apache.maven.shared.utils.StringUtils;

/**
 * @author Jason van Zyl
 */
public class BourneShell
    extends Shell
{
    private static final char DOUBLE_QUOTATION = '"';

    private static final char[] BASH_QUOTING_TRIGGER_CHARS =
        { ' ', '$', ';', '&', '|', '<', '>', '*', '?', '(', ')', '[', ']', '{', '}', '`' };

    /**
     * Create instance of BourneShell.
     */
    public BourneShell()
    {
        setShellCommand( "/bin/sh" );
        setArgumentQuoteDelimiter( DOUBLE_QUOTATION );
        setExecutableQuoteDelimiter( DOUBLE_QUOTATION );
        setSingleQuotedArgumentEscaped( true );
        setSingleQuotedExecutableEscaped( false );
        setQuotedExecutableEnabled( true );
    }

    /**
     * {@inheritDoc}
     */
    public String getExecutable()
    {
        if ( Os.isFamily( Os.FAMILY_WINDOWS ) )
        {
            return super.getExecutable();
        }

        return unifyQuotes( super.getExecutable() );
    }

    /** {@inheritDoc} */
    public List<String> getShellArgsList()
    {
        List<String> shellArgs = new ArrayList<String>();
        List<String> existingShellArgs = super.getShellArgsList();

        if ( ( existingShellArgs != null ) && !existingShellArgs.isEmpty() )
        {
            shellArgs.addAll( existingShellArgs );
        }

        shellArgs.add( "-c" );

        return shellArgs;
    }

    /** {@inheritDoc} */
    public String[] getShellArgs()
    {
        String[] shellArgs = super.getShellArgs();
        if ( shellArgs == null )
        {
            shellArgs = new String[0];
        }

        if ( ( shellArgs.length > 0 ) && !shellArgs[shellArgs.length - 1].equals( "-c" ) )
        {
            String[] newArgs = new String[shellArgs.length + 1];

            System.arraycopy( shellArgs, 0, newArgs, 0, shellArgs.length );
            newArgs[shellArgs.length] = "-c";

            shellArgs = newArgs;
        }

        return shellArgs;
    }

    /** {@inheritDoc} */
    protected String getExecutionPreamble()
    {
        if ( getWorkingDirectoryAsString() == null )
        {
            return null;
        }

        String dir = getWorkingDirectoryAsString();
        StringBuilder sb = new StringBuilder();
        sb.append( "cd " );

        sb.append( unifyQuotes( dir ) );
        sb.append( " && " );

        return sb.toString();
    }

    /** {@inheritDoc} */
    protected char[] getQuotingTriggerChars()
    {
        return BASH_QUOTING_TRIGGER_CHARS;
    }

    /**
     * <p>Unify quotes in a path for the Bourne Shell.</p>
     * <p/>
     * <pre>
     * BourneShell.unifyQuotes(null)                       = null
     * BourneShell.unifyQuotes("")                         = (empty)
     * BourneShell.unifyQuotes("/test/quotedpath'abc")     = /test/quotedpath\'abc
     * BourneShell.unifyQuotes("/test/quoted path'abc")    = "/test/quoted path'abc"
     * BourneShell.unifyQuotes("/test/quotedpath\"abc")    = "/test/quotedpath\"abc"
     * BourneShell.unifyQuotes("/test/quoted path\"abc")   = "/test/quoted path\"abc"
     * BourneShell.unifyQuotes("/test/quotedpath\"'abc")   = "/test/quotedpath\"'abc"
     * BourneShell.unifyQuotes("/test/quoted path\"'abc")  = "/test/quoted path\"'abc"
     * </pre>
     *
     * @param path not null path.
     * @return the path unified correctly for the Bourne shell.
     */
    private static String unifyQuotes( String path )
    {
        if ( path == null )
        {
            return null;
        }

        if ( path.indexOf( ' ' ) == -1 && path.indexOf( '\'' ) != -1 && path.indexOf( '"' ) == -1 )
        {
            return StringUtils.escape( path );
        }

        return StringUtils.quoteAndEscape( path, '\"', BASH_QUOTING_TRIGGER_CHARS );
    }
}