/*
    * Copyright (C) 2013 Room Work eXperience
    *
    * This program is free software: you can redistribute it and/or modify
    * it under the terms of the GNU General Public License as published by
    * the Free Software Foundation, either version 3 of the License, or
    * (at your option) any later version.
    *
    * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program.  If not, see <http://www.gnu.org/licenses/>.
   */
  package net.rwx.maven.asciidoc.services.impl;
  
  import java.io.File;
  import java.io.IOException;
  import java.io.InputStream;
  import net.rwx.maven.asciidoc.backends.Backend;
  import net.rwx.maven.asciidoc.configuration.Document;
  import net.rwx.maven.asciidoc.services.AsciidocService;
  import net.rwx.maven.asciidoc.utils.FileUtils;
  import org.python.core.PyString;
  import org.python.core.PySystemState;
  import org.python.util.PythonInterpreter;
  
  public class AsciidocServiceImpl extends RootServiceImpl implements AsciidocService {
  
      private String asciidocProgramPath;
      
      public AsciidocServiceImpl() throws IOException {
          ClassLoader loader = this.getClass().getClassLoader();
          InputStream is = loader.getResourceAsStream( ARCHIVE_NAME );
          String temporaryDirectory = FileUtils.getTemporaryDirectory();
          FileUtils.uncompress( is, temporaryDirectory );
          setAsciidocProgramPath( temporaryDirectory );
      }
      
      /**
       * Launch Asciidoc script.
       * 
       * @param input Path to Asciidoc document to process
       * @param backend Determine output format for Asciidoc script
       * @param output Path to output file (file format should match backend)
       */
      @Override
      public void execute( String inputPath, Document document, Backend backend ) throws Exception {
          setOuputPath(inputPath, backend);
          PySystemState state = getPySystemState( inputPath, backend.getName(), getOuputPath() );
  
          PythonInterpreter interp = new PythonInterpreter( null, state );
          interp.set( "__file__", asciidocProgramPath );
          interp.execfile( asciidocProgramPath );
      }
      
      /**
       * Initialize parameters and working dir for Jython interpreter.
       * 
       * @param input Path to Asciidoc document to process
       * @param backend Determine output format for Asciidoc script
       * @param output Path to output file (file format should match backend)
       * @return a system state for Jython interpreter
       */
      private PySystemState getPySystemState( String input, String backend, String output ) {
          PySystemState state = new PySystemState();
          
          state.argv.clear();
          state.argv.append( new PyString( asciidocProgramPath ) );
          state.argv.append( new PyString( "-b" ) );
          state.argv.append( new PyString( backend ) );
          state.argv.append( new PyString( "-a" ) );
          state.argv.append( new PyString( "icons" ) );
          state.argv.append( new PyString( "--out-file=" + output ) );
          state.argv.append( new PyString( input ) );
          
          File fInput = new File( input );
          state.setCurrentWorkingDir( fInput.getParent() );
          
          return state;
      }
      
      /**
       * Build path to Asciidoc script based on temporary directory.
       */
      private void setAsciidocProgramPath( String temporaryDirectory ) {
          StringBuilder builder = new StringBuilder();
          builder.append( temporaryDirectory );
          builder.append( File.separator );
          builder.append( "asciidoc-" );
          builder.append( VERSION );
          builder.append( File.separator );
          builder.append( "asciidoc.py" );
          
          asciidocProgramPath = builder.toString();
      }
  
     @Override
     protected void setOuputPath(String inputPath, Backend backend) {
         setOutputPath(inputPath, backend.getAsciidocExtension());
     }
 }