/*

* Copyright (c) 2007 Nokia Corporation and/or its subsidiary(-ies). 

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description:  This class is used for converting media files

 *

*/

package com.nokia.tools.themeinstaller.mediaconverter;

import java.io.BufferedReader;

import java.io.File;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.net.URL;

import java.util.ArrayList;

import java.util.Iterator;

import java.util.List;

import javax.imageio.IIOImage;

import javax.imageio.ImageIO;

import javax.imageio.ImageReader;

import javax.imageio.ImageWriter;

import javax.imageio.stream.ImageInputStream;

import javax.imageio.stream.ImageOutputStream;

import com.nokia.tools.themeinstaller.odtconverter.ConverterProperties;

/**

 * Base class for different MediaConverters

 * Media converters are used for e.g. converting jpg to mbm

 * @author jutarhon

 *

 */

public class MediaConverter

    {

    protected static final String MEDIA_CONVERTER_APPLICATION= "media_converter";

    private static final String WINDOWS_EXCUTABLE_EXTENSION = "exe";

    private static final String LINUX_OS_NAME = "linux";

    private static final String OPERATING_SYSTEM_PROPERTY = "os.name";

    protected static final char SPACE = ' ';

    protected static final char DOT = '.';

    private static final String BMP = "bmp";

    private static final String COLOR_SETTING = "color_setting";

    protected static String DEFAULT_SUCCESS_LINE = "Success.";

    protected ConverterProperties iProperties;

    private Process iProcess;

    protected String iExtraParameters = null;

    /**

     * Default constructor.

     * @throws IOException If loading properties fails

     */

    public MediaConverter() throws IOException

        {

        iProperties = new ConverterProperties();

        }

    /**

     * Returns possible set extra parameters for running converter application

     * or null if not set

     * @return the iExtraParameters

     */

    public String getExtraParameters()

        {

        return iExtraParameters;

        }

    /**

     * Sets extra parameters for running converter application

     * Set null for unsetting

     * @param aExtraParameters Extra parameters to set

     */

    public void setExtraParameters( String aExtraParameters )

        {

        iExtraParameters = aExtraParameters;

        }

    /**

     * Returns command line parameters for specified filenames

     * including the actual executable

     * example: bmconv.exe target.mbm source.jpg

     * @param aFilenames List of filenames to added to command line

     * @param aTargetFile Filename for target bitmap

     * @return Executable parameters

     */

    protected String getExecParameters( List aFilenames, String aTargetFile )

        {

        StringBuffer sb = new StringBuffer();

        // Get the execution location

        URL resource =

                getClass().getProtectionDomain().getCodeSource().getLocation();

        File bin = new File( resource.getPath() );

        // Find the bmconv from the installation directory

        sb.append( bin.getParent() + File.separatorChar );

        // Windows uses bmconv.exe and Linux bmconv

        if ( System.getProperty( OPERATING_SYSTEM_PROPERTY ).equalsIgnoreCase(

                LINUX_OS_NAME ) )

            {

            sb.append( iProperties.getProperty( MEDIA_CONVERTER_APPLICATION ) );

            }

        else

            {

            sb.append( iProperties.getProperty( MEDIA_CONVERTER_APPLICATION )

                    + DOT + WINDOWS_EXCUTABLE_EXTENSION );

            }

        sb.append( SPACE );

        if( iExtraParameters != null )

            {

            sb.append( iExtraParameters );

            sb.append( SPACE );

            }

        sb.append( aTargetFile );

        sb.append( SPACE );

        for ( Iterator iterator = aFilenames.iterator(); iterator.hasNext(); )

            {

            sb.append( iProperties.getProperty( COLOR_SETTING ) );

            sb.append( iterator.next() );

            if( iterator.hasNext() )

                {

                sb.append( SPACE );

                }

            }

        return sb.toString();

        }

    /**

     * Getter for environment variables in form "key=value"

     * To be overwritten in derived class if environment variables are needed

     * @return String array of "key=value" pairs.

     */

    protected String[] getEnvironmentVariables()

        {

        return null;

        }

    /**

     * Returns success line that is excepted in output

     * @return Success line

     */

    protected String getSuccesIndicationLine()

        {

        return DEFAULT_SUCCESS_LINE;

        }

    /**

     * Cancels the executing conversion operation

     */

    public void cancelConversion()

        {

        if( iProcess != null )

            {

            iProcess.destroy();

            }

        }

    /**

     * Converts one ore more files to target file

     * @param aFilenames Files to be converted

     * @param aTargetFile Target file

     * @throws IOException If IO error occurs or tool fails conversion

     */

    public void convertMedia( List aFilenames,

                              String aTargetFile ) throws IOException

        {

        ArrayList newFiles = new ArrayList();

        checkMedias( aFilenames, newFiles );

        Runtime rt = Runtime.getRuntime();

        iProcess = rt.exec( getExecParameters( aFilenames, aTargetFile ),

                                getEnvironmentVariables() );

        try

            {

            iProcess.waitFor();

            }

        catch ( InterruptedException e )

            {

            throw new IOException( "Conversion interrupted" );

            }

        if( iProcess.exitValue() != 0 )

            {

            InputStream input = null;

            BufferedReader in = null;

            StringBuffer sb = null;

            try

                {

                // reading the error logs

                input = iProcess.getErrorStream();

                in = new BufferedReader( new InputStreamReader( input ) );

                sb = new StringBuffer();

                String line = null;

                while ( ( line = in.readLine() ) != null )

                    {

                    sb.append( line );

                    sb.append( '\n' );

                    }

                }

            finally

                {

                if( input != null )

                    {

                    input.close();

                    }

                if( in != null )

                    {

                    in.close();

                    }

                }

            deleteTemporaryFiles( newFiles );

            throw new IOException( "Conversion failed with error code: " +

                                   iProcess.exitValue() +

                                   "\nError log: " + sb.toString() );

            }

        // read the output logs, and check that there is success indication (in case that tool does not

        // support sending error code)

        boolean success = false;

        String line = null;

        String lastLine = null;

        InputStream input = null;

        BufferedReader in = null;

        try

            {

            input = iProcess.getInputStream();

            in = new BufferedReader( new InputStreamReader( input ) );

            while ( ( line = in.readLine() ) != null )

                {

                if( line.equals( getSuccesIndicationLine() ) )

                    {

                    success = true;

                    break;

                    }

                lastLine = line;

                }

            }

        finally

            {

            if( input != null )

                {

                input.close();

                }

            if( in != null )

                {

                in.close();

                }

            }

        iProcess = null;

        // Delete temporary files

        deleteTemporaryFiles( newFiles );

        // did not found success line

        if( !success )

            {

            throw new IOException( "Running media converter failed: " + lastLine );

            }

        }

    /**

     * Delete temporary files

     * @param newFiles List of temporary files

     * @throws IOException If file deletion fails

     */

    protected void deleteTemporaryFiles( List aNewFiles ) throws IOException

        {

        for ( Iterator iterator = aNewFiles.iterator(); iterator.hasNext(); )

            {

            String filename = ( String ) iterator.next();

            File file = new File( filename );

            if( !file.delete() )

                {

                throw new IOException( "Temporary file deletion failed: " + filename );

                }

            }

        }

    /**

     * Checks that input medias does not contain illegal files and converts

     * other image formats to BMP

     * @param aFilenames List of files to be added in MBM file

     * @param aNewFiles List of created temporary files

     * @throws IOException thrown if some of encoders are missing, or some error in image reading/writing

     */

    protected void checkMedias( List aFilenames,

                                List aNewFiles ) throws IOException

        {

        // load BMP writer

        Iterator writers = ImageIO.getImageWritersByFormatName( BMP );

        if( !writers.hasNext() )

            {

            throw new IOException( "BMP encoder not found" );

            }

        ImageWriter bmpWriter = ( ImageWriter ) writers.next();

        ArrayList newNames = new ArrayList();

        // Go through all files and check if there is something else than BMP

        for ( Iterator iterator = aFilenames.iterator();

              iterator.hasNext(); )

            {

            String imageName = ( String ) iterator.next();

            ImageInputStream input = ImageIO.createImageInputStream(

                    new File( imageName ) );

            String destinationImage = null;

            try

                {

                Iterator readers = ImageIO.getImageReaders( input );

                if( !readers.hasNext() )

                    {

                    throw new IOException( "Unknown file" );

                    }

                ImageReader ir = ( ImageReader ) readers.next();

                //Convert file if it is not BMP

                destinationImage = imageName;

                if( !ir.getFormatName().equalsIgnoreCase( BMP ) )

                    {

                    // read original image

                    ir.setInput( input );

                    IIOImage image = ir.readAll( 0, null );

                    destinationImage = imageName.substring(

                            0, imageName.lastIndexOf( DOT ) + 1 ) + BMP;

                    File destFile = new File( destinationImage );

                    int index = 1;

                    // create unique name to not overwrite any existing files

                    while( destFile.exists() )

                        {

                        destinationImage = imageName.substring( 0,

                                           imageName.lastIndexOf( DOT ) )

                                           + index++ + DOT + BMP;

                        destFile = new File( destinationImage );

                        }

                    // Write image back in BMP format

                    ImageOutputStream output =

                            ImageIO.createImageOutputStream( destFile );

                    try

                        {

                        bmpWriter.setOutput( output );

                        bmpWriter.write( image );

                        }

                    finally

                        {

                        if( output != null )

                            {

                            output.close();

                            }

                        }

                    aNewFiles.add( destinationImage );

                    }

                }

            finally

                {

                if( input != null )

                    {

                    input.close();

                    }

                }

            newNames.add( destinationImage );

            }

        // change new names to list

        aFilenames.clear();

        aFilenames.addAll( newNames );

        }

    }