package org.apache.maven.cli;

/*
 * 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;

public class CleanArgument
{
    public static String[] cleanArgs( String[] args )
    {
        List<String> cleaned = new ArrayList<>();

        StringBuilder currentArg = null;

        for ( String arg : args )
        {
            boolean addedToBuffer = false;

            if ( arg.startsWith( "\"" ) )
            {
                // if we're in the process of building up another arg, push it and start over.
                // this is for the case: "-Dfoo=bar "-Dfoo2=bar two" (note the first unterminated quote)
                if ( currentArg != null )
                {
                    cleaned.add( currentArg.toString() );
                }

                // start building an argument here.
                currentArg = new StringBuilder( arg.substring( 1 ) );
                addedToBuffer = true;
            }

            // this has to be a separate "if" statement, to capture the case of: "-Dfoo=bar"
            if ( addedToBuffer && arg.endsWith( "\"" ) )
            {
                String cleanArgPart = arg.substring( 0, arg.length() - 1 );

                // if we're building an argument, keep doing so.
                if ( currentArg != null )
                {
                    // if this is the case of "-Dfoo=bar", then we need to adjust the buffer.
                    if ( addedToBuffer )
                    {
                        currentArg.setLength( currentArg.length() - 1 );
                    }
                    // otherwise, we trim the trailing " and append to the buffer.
                    else
                    {
                        // TODO: introducing a space here...not sure what else to do but collapse whitespace
                        currentArg.append( ' ' ).append( cleanArgPart );
                    }

                    cleaned.add( currentArg.toString() );
                }
                else
                {
                    cleaned.add( cleanArgPart );
                }

                currentArg = null;
                addedToBuffer = false;
                continue;
            }

            // if we haven't added this arg to the buffer, and we ARE building an argument
            // buffer, then append it with a preceding space...again, not sure what else to
            // do other than collapse whitespace.
            // NOTE: The case of a trailing quote is handled by nullifying the arg buffer.
            if ( !addedToBuffer )
            {
                if ( currentArg != null )
                {
                    currentArg.append( ' ' ).append( arg );
                }
                else
                {
                    cleaned.add( arg );
                }
            }
        }

        if ( currentArg != null )
        {
            cleaned.add( currentArg.toString() );
        }

        int cleanedSz = cleaned.size();

        String[] cleanArgs;

        if ( cleanedSz == 0 )
        {
            cleanArgs = args;
        }
        else
        {
            cleanArgs = cleaned.toArray( new String[cleanedSz] );
        }

        return cleanArgs;
    }


}
