/**************************************************************
 *
 * 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.
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package com.sun.star.help;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;
import java.util.zip.CRC32;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.analysis.cjk.CJKAnalyzer;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.util.Version;
import org.apache.lucene.store.NIOFSDirectory;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.Date;

/**
   When this tool is used with long path names on Windows, that is paths which start
   with \\?\, then the caller must make sure that the path is unique. This is achieved
   by removing '.' and '..' from the path. Paths which are created by
   osl_getSystemPathFromFileURL fulfill this requirement. This is necessary because
   lucene is patched to not use File.getCanonicalPath. See long_path.patch in the lucene
   module.
 */

public class HelpIndexerTool
{
    public HelpIndexerTool()
	{
    }


    /**
     * @param args the command line arguments
     */
    public static void main( String[] args )
	{
		boolean bExtensionMode = false;
		mainImpl( args, bExtensionMode );
	}

    public static void mainImpl( String[] args, boolean bExtensionMode )
	{
        String aDirToZipStr = "";
        String aSrcDirStr = "";
        String aLanguageStr = "";
        String aModule = "";
        String aTargetZipFileStr = "";
        String aCfsName = "";
        String aSegmentName = "";

        // Scan arguments
        //If this tool is invoked in the build process for extensions help,
        //then -extension must be set.
        boolean bExtension = false;
        boolean bLang = false;
        boolean bMod = false;
        boolean bZipDir = false;
        boolean bSrcDir = false;
        boolean bOutput = false;
        boolean bCfsName = false;
        boolean bSegmentName = false;

        int nArgCount = args.length;
        for( int i = 0 ; i < nArgCount ; i++ )
		{
            if( "-extension".equals(args[i]) )
			{
                bExtension = true;
            }
            else if( "-lang".equals(args[i]) )
			{
                if( i + 1 < nArgCount )
				{
                    aLanguageStr = args[i + 1];
                    bLang = true;
                }
                i++;
            }
			else if( "-mod".equals(args[i]) )
			{
                if( i + 1 < nArgCount )
				{
                    aModule = args[i + 1];
                    bMod = true;
                }
                i++;
            }
			else if( "-zipdir".equals(args[i]) )
			{
                if( i + 1 < nArgCount )
				{
                    aDirToZipStr = args[i + 1];
                    bZipDir = true;
                }
                i++;
            }
			else if( "-srcdir".equals(args[i]) )
			{
                if( i + 1 < nArgCount )
				{
                    aSrcDirStr = args[i + 1];
                    bSrcDir = true;
                }
                i++;
            }
			else if( "-o".equals(args[i]) )
			{
                if( i + 1 < nArgCount )
				{
                    aTargetZipFileStr = args[i + 1];
                    bOutput = true;
                }
                i++;
            }
			else if( "-checkcfsandsegname".equals(args[i]) )
			{
                if( i + 1 < nArgCount )
				{
                    aCfsName = args[i + 1] + ".cfs";
                    bCfsName = true;
                }
                i++;
                if( i + 1 < nArgCount )
				{
                    aSegmentName = "segments" + args[i + 1];
                    bSegmentName = true;
                }
                i++;
                if (!(bCfsName && bSegmentName))
                {
                    System.out.println("Usage: HelpIndexer -checkcfsandsegname _0 _3 (2 arguments needed)");
                    System.exit( -1 );
                }
            }
        }

        if( !bLang || !bMod || !bZipDir || (!bOutput && !bExtensionMode && !bExtension) )
		{
			if( bExtensionMode )
				return;

			System.out.println("Usage: HelpIndexer -lang ISOLangCode -mod HelpModule -zipdir TempZipDir -o OutputZipFile");
            System.out.println("Usage: HelpIndexer -extension -lang ISOLangCode -mod HelpModule -zipdir PathToLangDir");
			System.exit( -1 );
        }

        String aIndexDirName = aModule + ".idxl";
        File aIndexDir = new File( aDirToZipStr + File.separator + aIndexDirName );
		if( !bSrcDir )
			aSrcDirStr = aDirToZipStr;
        File aCaptionFilesDir = new File( aSrcDirStr + File.separator + "caption" );
        File aContentFilesDir = new File( aSrcDirStr + File.separator + "content" );

        try
		{
            Date start = new Date();
	    Analyzer analyzer = aLanguageStr.equals("ja") ? (Analyzer)new CJKAnalyzer(Version.LUCENE_29) : (Analyzer)new StandardAnalyzer(Version.LUCENE_29);
	    IndexWriter writer = new IndexWriter( NIOFSDirectory.open(aIndexDir), analyzer, true, IndexWriter.MaxFieldLength.UNLIMITED );
			if( !bExtensionMode )
	            System.out.println( "Lucene: Indexing to directory '" + aIndexDir + "'..." );
            int nRet = indexDocs( writer, aModule, bExtensionMode, aCaptionFilesDir, aContentFilesDir );
            if( nRet != -1 )
			{
				if( !bExtensionMode )
				{
					System.out.println();
					System.out.println( "Optimizing ..." );
				}
                writer.optimize();
            }
            writer.close();

			boolean bCfsFileOk = true;
			boolean bSegmentFileOk = true;
			if( bCfsName && bSegmentName && !bExtensionMode && nRet != -1 )
			{
				String aCompleteCfsFileName = aDirToZipStr + File.separator + aIndexDirName + File.separator + aCfsName;
				String aCompleteSegmentFileName = aDirToZipStr + File.separator + aIndexDirName + File.separator + aSegmentName;
				File aCfsFile = new File( aCompleteCfsFileName );
				File aSegmentFile = new File( aCompleteSegmentFileName );
				bCfsFileOk = aCfsFile.exists();
				bSegmentFileOk = aSegmentFile.exists();
				System.out.println( "Checking cfs file " + aCfsName+ ": " + (bCfsFileOk ? "Found" : "Not found") );
				System.out.println( "Checking segment file " + aSegmentName+ ": " + (bSegmentFileOk ? "Found" : "Not found") );
			}

			if( bExtensionMode || bExtension)
			{
				if( !bSrcDir )
				{
					deleteRecursively( aCaptionFilesDir );
					deleteRecursively( aContentFilesDir );
				}
			}
			else
			{
				if( nRet == -1 )
					deleteRecursively( aIndexDir );

				if( bCfsFileOk && bSegmentFileOk )
					System.out.println( "Zipping ..." );
				File aDirToZipFile = new File( aDirToZipStr );
				createZipFile( aDirToZipFile, aTargetZipFileStr );
				deleteRecursively( aDirToZipFile );
			}

			if( !bCfsFileOk )
			{
				System.out.println( "cfs file check failed, terminating..." );
				System.exit( -1 );
			}

			if( !bSegmentFileOk )
			{
				System.out.println( "segment file check failed, terminating..." );
				System.exit( -1 );
			}

			Date end = new Date();
			if( !bExtensionMode )
				System.out.println(end.getTime() - start.getTime() + " total milliseconds");
        }
		catch (IOException e)
		{
			if( bExtensionMode )
				return;

			System.out.println(" caught a " + e.getClass() +
				"\n with message: " + e.getMessage());
			System.exit( -1 );
        }
    }

	private static int indexDocs(IndexWriter writer, String aModule, boolean bExtensionMode,
		File aCaptionFilesDir, File aContentFilesDir) throws IOException
	{
        if( !aCaptionFilesDir.canRead() || !aCaptionFilesDir.isDirectory() )
		{
			if( !bExtensionMode )
	            System.out.println( "Not found: " + aCaptionFilesDir );
            return -1;
        }
        if( !aContentFilesDir.canRead() || !aContentFilesDir.isDirectory() )
		{
			if( !bExtensionMode )
	            System.out.println( "Not found: " + aContentFilesDir );
            return -1;
        }

        String[] aCaptionFiles = aCaptionFilesDir.list();
        List aCaptionFilesList = Arrays.asList( aCaptionFiles );
        HashSet aCaptionFilesHashSet = new HashSet( aCaptionFilesList );

        String[] aContentFiles = aContentFilesDir.list();
        List aContentFilesList = Arrays.asList( aContentFiles );
        HashSet aContentFilesHashSet = new HashSet( aContentFilesList );

        // Loop over caption files and find corresponding content file
		if( !bExtensionMode )
	        System.out.println( "Indexing, adding files" );
        int nCaptionFilesLen = aCaptionFiles.length;
        for( int i = 0 ; i < nCaptionFilesLen ; i++ )
		{
            String aCaptionFileStr = aCaptionFiles[i];
            File aCaptionFile = new File( aCaptionFilesDir, aCaptionFileStr );
            File aContentFile = null;
            if( aContentFilesHashSet.contains( aCaptionFileStr ) )
                aContentFile = new File( aContentFilesDir, aCaptionFileStr );

			if( !bExtensionMode )
				System.out.print( "." );
            writer.addDocument( HelpFileDocument.Document( aModule, aCaptionFile, aContentFile ) );
        }

        // Loop over content files to find remaining files not mapped to caption files
        int nContentFilesLen = aContentFiles.length;
        for( int i = 0 ; i < nContentFilesLen ; i++ )
		{
            String aContentFileStr = aContentFiles[i];
            if( !aCaptionFilesHashSet.contains( aContentFileStr ) )
			{
                // Not already handled in caption files loop
                File aCaptionFile = null;
                File aContentFile = new File( aContentFilesDir, aContentFileStr );
				if( !bExtensionMode )
					System.out.print( "." );
                writer.addDocument( HelpFileDocument.Document( aModule, aCaptionFile, aContentFile ) );
            }
        }
        return 0;
    }

    public static void createZipFile( File aDirToZip, String aTargetZipFileStr )
            throws FileNotFoundException, IOException
	{
        FileOutputStream fos = new FileOutputStream( aTargetZipFileStr );
        ZipOutputStream zos = new ZipOutputStream( fos );

        File[] aChildrenFiles = aDirToZip.listFiles();
        int nFileCount = aChildrenFiles.length;
        for( int i = 0 ; i < nFileCount ; i++ )
            addToZipRecursively( zos, aChildrenFiles[i], null );

        zos.close();
    }

    public static void addToZipRecursively( ZipOutputStream zos, File aFile, String aBasePath )
            throws FileNotFoundException, IOException
	{
        if( aFile.isDirectory() )
		{
            String aDirName = aFile.getName();
            if( aDirName.equalsIgnoreCase( "caption" ) || aDirName.equalsIgnoreCase( "content" ) )
                return;

            File[] aChildrenFiles = aFile.listFiles();
            String aNewBasePath = "";
            if( aBasePath != null )
                aNewBasePath += aBasePath + File.separator;
            aNewBasePath += aDirName;

            int nFileCount = aChildrenFiles.length;
            for( int i = 0 ; i < nFileCount ; i++ )
                addToZipRecursively( zos, aChildrenFiles[i], aNewBasePath );

            return;
        }

        // No directory
        // read contents of file we are going to put in the zip
        int fileLength = (int) aFile.length();
        FileInputStream fis = new FileInputStream( aFile );
        byte[] wholeFile = new byte[fileLength];
        int bytesRead = fis.read( wholeFile, 0, fileLength );
        fis.close();

        String aFileName = aFile.getName();
        String aEntryName = "";
        if( aBasePath != null )
            aEntryName += aBasePath + "/";
        aEntryName += aFileName;
        ZipEntry aZipEntry = new ZipEntry( aEntryName );
        aZipEntry.setTime( aFile.lastModified() );
        aZipEntry.setSize( fileLength );

        int nMethod = ( aFileName.toLowerCase().endsWith( ".jar" ) )
                ? ZipEntry.STORED : ZipEntry.DEFLATED;
        aZipEntry.setMethod( nMethod );

        CRC32 tempCRC = new CRC32();
        tempCRC.update( wholeFile, 0, wholeFile.length );
        aZipEntry.setCrc( tempCRC.getValue() );

        // write the contents into the zip element
        zos.putNextEntry( aZipEntry );
        zos.write( wholeFile, 0, fileLength );
        zos.closeEntry();
    }

    static public boolean deleteRecursively( File aFile )
	{
        if( aFile.isDirectory() )
		{
            File[] aChildrenFiles = aFile.listFiles();
            int nFileCount = aChildrenFiles.length;
            for( int i = 0 ; i < nFileCount ; i++ )
			{
                File aChildrenFile = aChildrenFiles[i];
                boolean bSuccess = deleteRecursively( aChildrenFile );
                if( !bSuccess )
                    return false;
            }
        }

        return aFile.delete();
    }
}