/*
 *   Copyright (C) Christian Schulte <cs@schulte.it>, 2005-206
 *   All rights reserved.
 *
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 *
 *     o Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *
 *     o Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
 *
 *   THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 *   INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
 *   AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
 *   THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY DIRECT, INDIRECT,
 *   INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *   NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 *   THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *   $JOMC: ResourceFileProcessor.java 5043 2015-05-27 07:03:39Z schulte $
 *
 */
package org.jomc.tools;

import java.io.ByteArrayOutputStream;
import java.io.Closeable;
import java.io.File;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.nio.channels.FileLock;
import java.text.MessageFormat;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;
import java.util.Properties;
import java.util.ResourceBundle;
import java.util.logging.Level;
import org.apache.velocity.VelocityContext;
import org.jomc.model.Implementation;
import org.jomc.model.JavaTypeName;
import org.jomc.model.Message;
import org.jomc.model.Messages;
import org.jomc.model.ModelObjectException;
import org.jomc.model.Module;
import org.jomc.model.Specification;
import org.jomc.model.Text;

/**
 * Processes resource files.
 *
 * <p>
 * <b>Use Cases:</b><br/><ul>
 * <li>{@link #writeResourceBundleResourceFiles(File) }</li>
 * <li>{@link #writeResourceBundleResourceFiles(Module, File) }</li>
 * <li>{@link #writeResourceBundleResourceFiles(Specification, File) }</li>
 * <li>{@link #writeResourceBundleResourceFiles(Implementation, File) }</li>
 * </ul></p>
 *
 * @author <a href="mailto:cs@schulte.it">Christian Schulte</a>
 * @version $JOMC: ResourceFileProcessor.java 5043 2015-05-27 07:03:39Z schulte $
 *
 * @see #getModules()
 */
public class ResourceFileProcessor extends JomcTool
{

    /**
     * The language of the default language properties file of generated resource bundle resources.
     */
    private Locale resourceBundleDefaultLocale;

    /**
     * Creates a new {@code ResourceFileProcessor} instance.
     */
    public ResourceFileProcessor()
    {
        super();
    }

    /**
     * Creates a new {@code ResourceFileProcessor} instance taking a {@code ResourceFileProcessor} instance to
     * initialize the instance with.
     *
     * @param tool The instance to initialize the new instance with.
     *
     * @throws NullPointerException if {@code tool} is {@code null}.
     * @throws IOException if copying {@code tool} fails.
     */
    public ResourceFileProcessor( final ResourceFileProcessor tool ) throws IOException
    {
        super( tool );
        this.resourceBundleDefaultLocale = tool.resourceBundleDefaultLocale;
    }

    /**
     * Gets the language of the default language properties file of generated resource bundle resource files.
     *
     * @return The language of the default language properties file of generated resource bundle resource files.
     *
     * @see #setResourceBundleDefaultLocale(java.util.Locale)
     */
    public final Locale getResourceBundleDefaultLocale()
    {
        if ( this.resourceBundleDefaultLocale == null )
        {
            this.resourceBundleDefaultLocale = Locale.ENGLISH;

            if ( this.isLoggable( Level.CONFIG ) )
            {
                this.log( Level.CONFIG, getMessage( "defaultResourceBundleDefaultLocale",
                                                    this.resourceBundleDefaultLocale ), null );

            }
        }

        return this.resourceBundleDefaultLocale;
    }

    /**
     * Sets the language of the default language properties file of generated resource bundle resource files.
     *
     * @param value The language of the default language properties file of generated resource bundle resource files.
     *
     * @see #getResourceBundleDefaultLocale()
     */
    public final void setResourceBundleDefaultLocale( final Locale value )
    {
        this.resourceBundleDefaultLocale = value;
    }

    /**
     * Writes resource bundle resource files of the modules of the instance to a given directory.
     *
     * @param resourcesDirectory The directory to write resource bundle resource files to.
     *
     * @throws NullPointerException if {@code resourcesDirectory} is {@code null}.
     * @throws IOException if writing resource bundle resource files fails.
     * @throws ModelObjectException if compiling the name of a referenced type fails.
     *
     * @see #writeResourceBundleResourceFiles(org.jomc.model.Module, java.io.File)
     */
    public void writeResourceBundleResourceFiles( final File resourcesDirectory )
        throws IOException, ModelObjectException
    {
        if ( resourcesDirectory == null )
        {
            throw new NullPointerException( "resourcesDirectory" );
        }

        if ( this.getModules() != null )
        {
            for ( int i = 0, s0 = this.getModules().getModule().size(); i < s0; i++ )
            {
                this.writeResourceBundleResourceFiles( this.getModules().getModule().get( i ), resourcesDirectory );
            }
        }
        else if ( this.isLoggable( Level.WARNING ) )
        {
            this.log( Level.WARNING, getMessage( "modulesNotFound", this.getModel().getIdentifier() ), null );
        }
    }

    /**
     * Writes resource bundle resource files of a given module from the modules of the instance to a given directory.
     *
     * @param module The module to process.
     * @param resourcesDirectory The directory to write resource bundle resource files to.
     *
     * @throws NullPointerException if {@code module} or {@code resourcesDirectory} is {@code null}.
     * @throws IOException if writing resource bundle resource files fails.
     * @throws ModelObjectException if compiling the name of a referenced type fails.
     *
     * @see #writeResourceBundleResourceFiles(org.jomc.model.Specification, java.io.File)
     * @see #writeResourceBundleResourceFiles(org.jomc.model.Implementation, java.io.File)
     */
    public void writeResourceBundleResourceFiles( final Module module, final File resourcesDirectory )
        throws IOException, ModelObjectException
    {
        if ( module == null )
        {
            throw new NullPointerException( "module" );
        }
        if ( resourcesDirectory == null )
        {
            throw new NullPointerException( "resourcesDirectory" );
        }

        if ( this.getModules() != null && this.getModules().getModule( module.getName() ) != null )
        {
            if ( module.getSpecifications() != null )
            {
                for ( int i = 0, s0 = module.getSpecifications().getSpecification().size(); i < s0; i++ )
                {
                    this.writeResourceBundleResourceFiles( module.getSpecifications().getSpecification().get( i ),
                                                           resourcesDirectory );

                }
            }

            if ( module.getImplementations() != null )
            {
                for ( int i = 0, s0 = module.getImplementations().getImplementation().size(); i < s0; i++ )
                {
                    this.writeResourceBundleResourceFiles( module.getImplementations().getImplementation().get( i ),
                                                           resourcesDirectory );

                }
            }
        }
        else if ( this.isLoggable( Level.WARNING ) )
        {
            this.log( Level.WARNING, getMessage( "moduleNotFound", module.getName() ), null );
        }
    }

    /**
     * Writes resource bundle resource files of a given specification from the modules of the instance to a directory.
     *
     * @param specification The specification to process.
     * @param resourcesDirectory The directory to write resource bundle resource files to.
     *
     * @throws NullPointerException if {@code specification} or {@code resourcesDirectory} is {@code null}.
     * @throws IOException if writing resource bundle resource files fails.
     * @throws ModelObjectException if compiling the name of the type referenced by the specification fails.
     *
     * @see #getResourceBundleResources(org.jomc.model.Specification)
     */
    public void writeResourceBundleResourceFiles( final Specification specification, final File resourcesDirectory )
        throws IOException, ModelObjectException
    {
        if ( specification == null )
        {
            throw new NullPointerException( "implementation" );
        }
        if ( resourcesDirectory == null )
        {
            throw new NullPointerException( "resourcesDirectory" );
        }

        if ( this.getModules() != null
                 && this.getModules().getSpecification( specification.getIdentifier() ) != null )
        {
            if ( specification.isClassDeclaration() )
            {
                if ( !resourcesDirectory.isDirectory() )
                {
                    throw new IOException( getMessage( "directoryNotFound", resourcesDirectory.getAbsolutePath() ) );
                }

                this.assertValidTemplates( specification );

                final JavaTypeName javaTypeName = specification.getJavaTypeName();

                if ( javaTypeName != null )
                {
                    final String bundlePath = javaTypeName.getQualifiedName().replace( '.', File.separatorChar );
                    this.writeResourceBundleResourceFiles(
                        this.getResourceBundleResources( specification ), resourcesDirectory, bundlePath );

                }
            }
        }
        else if ( this.isLoggable( Level.WARNING ) )
        {
            this.log( Level.WARNING, getMessage( "specificationNotFound", specification.getIdentifier() ), null );
        }
    }

    /**
     * Writes resource bundle resource files of a given implementation from the modules of the instance to a directory.
     *
     * @param implementation The implementation to process.
     * @param resourcesDirectory The directory to write resource bundle resource files to.
     *
     * @throws NullPointerException if {@code implementation} or {@code resourcesDirectory} is {@code null}.
     * @throws IOException if writing resource bundle resource files fails.
     * @throws ModelObjectException if compiling the name of the type referenced by the implementation fails.
     *
     * @see #getResourceBundleResources(org.jomc.model.Implementation)
     */
    public void writeResourceBundleResourceFiles( final Implementation implementation, final File resourcesDirectory )
        throws IOException, ModelObjectException
    {
        if ( implementation == null )
        {
            throw new NullPointerException( "implementation" );
        }
        if ( resourcesDirectory == null )
        {
            throw new NullPointerException( "resourcesDirectory" );
        }

        if ( this.getModules() != null
                 && this.getModules().getImplementation( implementation.getIdentifier() ) != null )
        {
            if ( implementation.isClassDeclaration() )
            {
                if ( !resourcesDirectory.isDirectory() )
                {
                    throw new IOException( getMessage( "directoryNotFound", resourcesDirectory.getAbsolutePath() ) );
                }

                this.assertValidTemplates( implementation );

                final JavaTypeName javaTypeName = implementation.getJavaTypeName();

                if ( javaTypeName != null )
                {
                    final String bundlePath = javaTypeName.getQualifiedName().replace( '.', File.separatorChar );
                    this.writeResourceBundleResourceFiles(
                        this.getResourceBundleResources( implementation ), resourcesDirectory, bundlePath );

                }
            }
        }
        else if ( this.isLoggable( Level.WARNING ) )
        {
            this.log( Level.WARNING, getMessage( "implementationNotFound", implementation.getIdentifier() ), null );
        }
    }

    /**
     * Gets resource bundle properties resources of a given specification.
     *
     * @param specification The specification to get resource bundle properties resources of.
     *
     * @return Resource bundle properties resources of {@code specification} or {@code null}, if no model objects are
     * found.
     *
     * @throws NullPointerException if {@code specification} is {@code null}.
     * @throws IOException if getting the resource bundle properties resources fails.
     */
    public Map<Locale, Properties> getResourceBundleResources( final Specification specification )
        throws IOException
    {
        if ( specification == null )
        {
            throw new NullPointerException( "specification" );
        }

        Map<Locale, Properties> properties = null;

        if ( this.getModules() != null
                 && this.getModules().getSpecification( specification.getIdentifier() ) != null )
        {
            properties = new HashMap<Locale, Properties>();
        }
        else if ( this.isLoggable( Level.WARNING ) )
        {
            this.log( Level.WARNING, getMessage( "specificationNotFound", specification.getIdentifier() ), null );
        }

        return properties;
    }

    /**
     * Gets resource bundle properties resources of a given implementation.
     *
     * @param implementation The implementation to get resource bundle properties resources of.
     *
     * @return Resource bundle properties resources of {@code implementation} or {@code null}, if no model objects are
     * found.
     *
     * @throws NullPointerException if {@code implementation} is {@code null}.
     * @throws IOException if getting the resource bundle properties resources fails.
     */
    public Map<Locale, Properties> getResourceBundleResources( final Implementation implementation )
        throws IOException
    {
        if ( implementation == null )
        {
            throw new NullPointerException( "implementation" );
        }

        Map<Locale, Properties> properties = null;

        if ( this.getModules() != null
                 && this.getModules().getImplementation( implementation.getIdentifier() ) != null )
        {
            properties = new HashMap<Locale, java.util.Properties>( 10 );
            final Messages messages = this.getModules().getMessages( implementation.getIdentifier() );

            if ( messages != null )
            {
                for ( int i = 0, s0 = messages.getMessage().size(); i < s0; i++ )
                {
                    final Message message = messages.getMessage().get( i );

                    if ( message.getTemplate() != null )
                    {
                        for ( int j = 0, s1 = message.getTemplate().getText().size(); j < s1; j++ )
                        {
                            final Text text = message.getTemplate().getText().get( j );
                            final Locale locale = new Locale( text.getLanguage().toLowerCase() );
                            Properties bundleProperties = properties.get( locale );

                            if ( bundleProperties == null )
                            {
                                bundleProperties = new Properties();
                                properties.put( locale, bundleProperties );
                            }

                            bundleProperties.setProperty( message.getName(), text.getValue() );
                        }
                    }
                }
            }
        }
        else if ( this.isLoggable( Level.WARNING ) )
        {
            this.log( Level.WARNING, getMessage( "implementationNotFound", implementation.getIdentifier() ), null );
        }

        return properties;
    }

    private void writeResourceBundleResourceFiles( final Map<Locale, Properties> resources,
                                                   final File resourcesDirectory, final String bundlePath )
        throws IOException
    {
        if ( resources == null )
        {
            throw new NullPointerException( "resources" );
        }
        if ( resourcesDirectory == null )
        {
            throw new NullPointerException( "resourcesDirectory" );
        }
        if ( bundlePath == null )
        {
            throw new NullPointerException( "bundlePath" );
        }

        Properties defProperties = null;
        Properties fallbackProperties = null;

        final VelocityContext ctx = this.getVelocityContext();
        final String toolName = ctx.get( "toolName" ).toString();
        final String toolVersion = ctx.get( "toolVersion" ).toString();
        final String toolUrl = ctx.get( "toolUrl" ).toString();

        for ( final Map.Entry<Locale, Properties> e : resources.entrySet() )
        {
            final String language = e.getKey().getLanguage().toLowerCase();
            final Properties p = e.getValue();
            final File file = new File( resourcesDirectory, bundlePath + "_" + language + ".properties" );

            if ( this.getResourceBundleDefaultLocale().getLanguage().equalsIgnoreCase( language ) )
            {
                defProperties = p;
            }

            fallbackProperties = p;

            if ( !file.getParentFile().exists() && !file.getParentFile().mkdirs() )
            {
                throw new IOException( getMessage( "failedCreatingDirectory",
                                                   file.getParentFile().getAbsolutePath() ) );

            }

            if ( this.isLoggable( Level.INFO ) )
            {
                this.log( Level.INFO, getMessage( "writing", file.getCanonicalPath() ), null );
            }

            this.writePropertiesFile( p, toolName + ' ' + toolVersion + " - See " + toolUrl, file );
        }

        if ( defProperties == null )
        {
            defProperties = fallbackProperties;
        }

        if ( defProperties != null )
        {
            final File file = new File( resourcesDirectory, bundlePath + ".properties" );

            if ( !file.getParentFile().exists() && !file.getParentFile().mkdirs() )
            {
                throw new IOException( getMessage( "failedCreatingDirectory",
                                                   file.getParentFile().getAbsolutePath() ) );

            }

            if ( this.isLoggable( Level.INFO ) )
            {
                this.log( Level.INFO, getMessage( "writing", file.getCanonicalPath() ), null );
            }

            this.writePropertiesFile( defProperties, toolName + ' ' + toolVersion + " - See " + toolUrl, file );
        }
    }

    private void assertValidTemplates( final Specification specification )
    {
        if ( specification == null )
        {
            throw new NullPointerException( "specification" );
        }
    }

    private void assertValidTemplates( final Implementation implementation )
    {
        if ( implementation == null )
        {
            throw new NullPointerException( "implementation" );
        }

        final Messages messages = this.getModules().getMessages( implementation.getIdentifier() );

        if ( messages != null )
        {
            for ( int i = messages.getMessage().size() - 1; i >= 0; i-- )
            {
                final Message m = messages.getMessage().get( i );

                if ( m.getTemplate() != null )
                {
                    for ( int j = m.getTemplate().getText().size() - 1; j >= 0; j-- )
                    {
                        new MessageFormat( m.getTemplate().getText().get( j ).getValue() );
                    }
                }
            }
        }
    }

    private void writePropertiesFile( final Properties properties, final String comments, final File propertiesFile )
        throws IOException
    {
        RandomAccessFile randomAccessFile = null;
        FileChannel fileChannel = null;
        FileLock fileLock = null;
        boolean suppressExceptionOnClose = true;

        final ByteArrayOutputStream byteStream = new ByteArrayOutputStream();
        properties.store( byteStream, comments );
        byteStream.close();

        final byte[] bytes = byteStream.toByteArray();

        try
        {
            randomAccessFile = new RandomAccessFile( propertiesFile, "rw" );
            fileChannel = randomAccessFile.getChannel();
            fileLock = fileChannel.lock();
            fileChannel.truncate( bytes.length );
            fileChannel.position( 0L );
            fileChannel.write( ByteBuffer.wrap( bytes ) );
            fileChannel.force( true );
            suppressExceptionOnClose = false;
        }
        finally
        {
            this.releaseAndClose( fileLock, fileChannel, randomAccessFile, suppressExceptionOnClose );
        }
    }

    private void releaseAndClose( final FileLock fileLock, final FileChannel fileChannel,
                                  final Closeable closeable, final boolean suppressExceptions )
        throws IOException
    {
        try
        {
            if ( fileLock != null )
            {
                fileLock.release();
            }
        }
        catch ( final IOException e )
        {
            if ( suppressExceptions )
            {
                this.log( Level.SEVERE, null, e );
            }
            else
            {
                throw e;
            }
        }
        finally
        {
            try
            {
                if ( fileChannel != null )
                {
                    fileChannel.close();
                }
            }
            catch ( final IOException e )
            {
                if ( suppressExceptions )
                {
                    this.log( Level.SEVERE, null, e );
                }
                else
                {
                    throw e;
                }
            }
            finally
            {
                try
                {
                    if ( closeable != null )
                    {
                        closeable.close();
                    }
                }
                catch ( final IOException e )
                {
                    if ( suppressExceptions )
                    {
                        this.log( Level.SEVERE, null, e );
                    }
                    else
                    {
                        throw e;
                    }
                }
            }
        }
    }

    private static String getMessage( final String key, final Object... arguments )
    {
        if ( key == null )
        {
            throw new NullPointerException( "key" );
        }

        return MessageFormat.format( ResourceBundle.getBundle(
            ResourceFileProcessor.class.getName().replace( '.', '/' ) ).getString( key ), arguments );

    }

}