package org.apache.maven.scm.provider.git;
   
   /*
    * 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.codehaus.plexus.util.StringUtils;
  
  import java.io.BufferedReader;
  import java.io.File;
  import java.io.FileReader;
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.Iterator;
  import java.util.List;
  
  /**
   * @author <a href="mailto:evenisse@apache.org">Emmanuel Venisse</a>
   *
   */
  public class GitConfigFileReader
  {
      private File configDirectory;
  
      public File getConfigDirectory()
      {
          if ( configDirectory == null )
          {
              
              File confDir = new File( ".git" );
              
              if ( confDir.exists() ) 
              {
                  configDirectory = confDir;
              }
              else 
              {
                  confDir = new File( "." );
                  
                  if ( confDir.exists() ) 
                  {
                      configDirectory = confDir;
                  }
              }
              
          }
  
          return configDirectory;
      }
  
      public void setConfigDirectory( File configDirectory )
      {
          this.configDirectory = configDirectory;
      }
  
      public String getProperty( String group, String propertyName )
      {
          List<String> lines = getConfLines();
  
          boolean inGroup = false;
          for ( Iterator<String> i = lines.iterator(); i.hasNext(); )
          {
              String line = i.next().trim();
  
              if ( !inGroup )
              {
                  if ( ( "[" + group + "]" ).equals( line ) )
                  {
                      inGroup = true;
                  }
              }
              else
              {
                  if ( line.startsWith( "[" ) && line.endsWith( "]" ) )
                  {
                      //a new group start
                      return null;
                  }
  
                  if ( line.startsWith( "#" ) )
                  {
                      continue;
                  }
                  if ( line.indexOf( '=' ) < 0 )
                 {
                     continue;
                 }
 
                 String property = line.substring( 0, line.indexOf( '=' ) ).trim();
 
                 if ( !property.equals( propertyName ) )
                 {
                     continue;
                 }
 
                 String value = line.substring( line.indexOf( '=' ) + 1 );
                 return value.trim();
             }
         }
 
         return null;
     }
 
     /**
      * Load the git config file
      *
      * @return the list of all lines
      */
     private List<String> getConfLines()
     {
         List<String> lines = new ArrayList<>();
 
         try
         {
             if ( getConfigDirectory().exists() )
             {
                 try ( BufferedReader reader = new BufferedReader( new FileReader(
                         new File( getConfigDirectory(), "config" ) ) ) )
                 {
                     String line;
                     while ( ( line = reader.readLine() ) != null )
                     {
                         if ( !line.startsWith( "#" ) && StringUtils.isNotEmpty( line ) )
                         {
                             lines.add( line );
                         }
                     }
                 }
             }
         }
         catch ( IOException e )
         {
             lines.clear();
         }
 
         return lines;
     }
 }