package org.apache.maven.scm.provider.hg;

 /*

  * 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.ScmException;

 import org.apache.maven.scm.ScmFileStatus;

 import org.apache.maven.scm.log.DefaultLog;

 import org.apache.maven.scm.provider.hg.command.HgCommandConstants;

 import org.apache.maven.scm.provider.hg.command.HgConsumer;

 import org.codehaus.plexus.util.cli.Commandline;

 import java.io.File;

 /**

  * Check hg installation.

  *

  * @author <a href="mailto:thurner.rupert@ymono.net">thurner rupert</a>

  * @author <a href="mailto:ryan@darksleep.com">ryan daum</a>

  * @version $Id: HgConfig.java 686566 2008-08-16 21:52:46Z olamy $

  */

 public class HgConfig

 {

     //Minimum version for the Hg SCM

     private static final String HG_REQ = "0.9.2";

     // The string which indicates the beginning of the Mercurial line

     private static final String HG_VERSION_TAG = "ercurial Distributed SCM (version ";

     // URL to download mercurial from

     private static final String HG_INSTALL_URL = "'http://www.selenic.com/mercurial/wiki/index.cgi/Download'";

     //Configuration to check with default values (not installed)

     private HgVersionConsumer hgVersion = new HgVersionConsumer( null );

     HgConfig( File workingDir )

     {

         try

         {

             hgVersion = getHgVersion( workingDir );

         }

         catch ( ScmException e )

         {

             //Ignore -  is not installed.

             //This is already recorded thus we do not generate more info.

         }

     }

     /**

      * @return True if one can run basic hg commands

      */

     private boolean isInstalled()

     {

         return hgVersion.isVersionOk( HG_REQ );

     }

     /**

      * @return True if all modules for hg are installed.

      */

     private boolean isComplete()

     {

         return isInstalled();

     }

     // Consumer to find the Mercurial version

     public static HgVersionConsumer getHgVersion( File workingDir )

         throws ScmException

     {

         String[] versionCmd = new String[]{HgCommandConstants.VERSION};

         HgVersionConsumer consumer = new HgVersionConsumer( HG_VERSION_TAG );

         Commandline cmd = HgUtils.buildCmd( workingDir, versionCmd );

         // Execute command

         HgUtils.executeCmd( consumer, cmd );

         // Return result

         return consumer;

     }

     /**

      * Iterate through two dot-notation version strings, normalize them to the same length, then

      * do alphabetic comparison

      *

      * @param version1

      * @param version2

      * @return true if version2 is greater than version1

      */

     private static boolean compareVersion( String version1, String version2 )

     {

         int l1, l2;

         String v1, v2;

         v1 = version1;

         v2 = version2;

         l1 = version1.length();

         l2 = version2.length();

         if ( l1 > l2 )

         {

             for ( int x = l2; x >= l1; x-- )

             {

                 v2 += ' ';

             }

         }

         if ( l2 > l1 )

         {

             for ( int x = l1; x <= l2; x++ )

             {

                 v1 += ' ';

             }

         }

         return v2.compareTo( v1 ) >= 0;

     }

     /**

      * Get version of the executable.

      * Version is resolved by splitting the line starting with the version tag and finding

      * the second last word.

      */

     private static class HgVersionConsumer

         extends HgConsumer

     {

         private String versionStr = "NA";

         private String versionTag;

         HgVersionConsumer( String versionTag )

         {

             super( new DefaultLog() );

             this.versionTag = versionTag;

         }

         public void doConsume( ScmFileStatus status, String line )

         {

             if ( line.startsWith( versionTag ) )

             {

                 String[] elements = line.split( " " );

                 versionStr = elements[elements.length - 1].split( "\\)" )[0];

             }

         }

         String getVersion()

         {

             return versionStr;

         }

         boolean isVersionOk( String version )

         {

             // build one number out of the whole version #

             return compareVersion( version, versionStr );

         }

     }

     private String getInstalledStr()

     {

         if ( isComplete() )

         {

             return "valid and complete.";

         }

         return ( isInstalled() ? "incomplete. " : "invalid. " ) + "Consult " + HG_INSTALL_URL;

     }

     public String toString( File workingDir )

     {

         boolean hgOk = hgVersion.isVersionOk( HG_REQ );

         return "\n  Your Hg installation seems to be " + getInstalledStr() + "\n    Hg version: "

             + hgVersion.getVersion() + ( hgOk ? " (OK)" : " (May be INVALID)" ) + "\n";

     }

 }