package org.apache.maven.scm.command.changelog;

/*
 * 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 org.apache.maven.scm.CommandParameter;
import org.apache.maven.scm.CommandParameters;
import org.apache.maven.scm.ScmBranch;
import org.apache.maven.scm.ScmException;
import org.apache.maven.scm.ScmFileSet;
import org.apache.maven.scm.ScmResult;
import org.apache.maven.scm.ScmVersion;
import org.apache.maven.scm.command.AbstractCommand;
import org.apache.maven.scm.provider.ScmProviderRepository;
import org.codehaus.plexus.util.StringUtils;

import java.util.Date;

/**
 * @author <a href="mailto:trygvis@inamo.no">Trygve Laugst&oslash;l</a>
 * @version $Id$
 */
public abstract class AbstractChangeLogCommand
    extends AbstractCommand
    implements ChangeLogCommand
{
    protected abstract ChangeLogScmResult executeChangeLogCommand( ScmProviderRepository repository, ScmFileSet fileSet,
                                                                   Date startDate, Date endDate, ScmBranch branch,
                                                                   String datePattern )
        throws ScmException;

    protected ChangeLogScmResult executeChangeLogCommand( ScmProviderRepository repository, ScmFileSet fileSet,
                                                          ScmVersion startVersion, ScmVersion endVersion,
                                                          String datePattern )
        throws ScmException
    {
        throw new ScmException( "Unsupported method for this provider." );
    }

    public ScmResult executeCommand( ScmProviderRepository repository, ScmFileSet fileSet,
                                     CommandParameters parameters )
        throws ScmException
    {
        Date startDate = parameters.getDate( CommandParameter.START_DATE, null );

        Date endDate = parameters.getDate( CommandParameter.END_DATE, null );

        int numDays = parameters.getInt( CommandParameter.NUM_DAYS, 0 );

        ScmBranch branch = (ScmBranch) parameters.getScmVersion( CommandParameter.BRANCH, null );

        ScmVersion startVersion = parameters.getScmVersion( CommandParameter.START_SCM_VERSION, null );

        ScmVersion endVersion = parameters.getScmVersion( CommandParameter.END_SCM_VERSION, null );

        String datePattern = parameters.getString( CommandParameter.CHANGELOG_DATE_PATTERN, null );

        if ( startVersion != null && StringUtils.isNotEmpty( startVersion.getName() ) )
        {
            return executeChangeLogCommand( repository, fileSet, startVersion, endVersion, datePattern );
        }
        else
        {
            if ( numDays != 0 && ( startDate != null || endDate != null ) )
            {
                throw new ScmException( "Start or end date cannot be set if num days is set." );
            }

            if ( endDate != null && startDate == null )
            {
                throw new ScmException( "The end date is set but the start date isn't." );
            }

            if ( numDays > 0 )
            {
                startDate = new Date( System.currentTimeMillis() - (long) numDays * 24 * 60 * 60 * 1000 );

                endDate = new Date( System.currentTimeMillis() + (long) 1 * 24 * 60 * 60 * 1000 );
            }
            else if ( endDate == null )
            {
                endDate = new Date();
            }

            return executeChangeLogCommand( repository, fileSet, startDate, endDate, branch, datePattern );
        }
    }
}