content: /*
   * Copyright (C) 2010.
   * All rights reserved.
   */
  package ro.isdc.wro.extensions.processor.js;
  
  import java.io.IOException;
  import java.io.Reader;
  import java.io.Writer;
  
  import org.apache.commons.io.IOUtils;
  import org.apache.commons.lang3.StringUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import ro.isdc.wro.WroRuntimeException;
  import ro.isdc.wro.extensions.processor.support.ObjectPoolHelper;
  import ro.isdc.wro.extensions.processor.support.coffeescript.CoffeeScript;
  import ro.isdc.wro.model.resource.Resource;
  import ro.isdc.wro.model.resource.ResourceType;
  import ro.isdc.wro.model.resource.SupportedResourceType;
  import ro.isdc.wro.model.resource.processor.Destroyable;
  import ro.isdc.wro.model.resource.processor.ResourcePostProcessor;
  import ro.isdc.wro.model.resource.processor.ResourcePreProcessor;
  import ro.isdc.wro.util.ObjectFactory;
  
  
  
  /**
   * Uses coffee script library loaded from the webjar to compile to javascript code.
   *
   * @author Alex Objelean
   * @created 26 Mar 2011
   * @since 1.3.6
   */
  @SupportedResourceType(ResourceType.JS)
  public class RhinoCoffeeScriptProcessor
    implements ResourcePreProcessor, ResourcePostProcessor, Destroyable {
    private static final Logger LOG = LoggerFactory.getLogger(RhinoCoffeeScriptProcessor.class);
    public static final String ALIAS = "rhinoCoffeeScript";
    private ObjectPoolHelper<CoffeeScript> enginePool;
  
  
    public RhinoCoffeeScriptProcessor() {
      enginePool = new ObjectPoolHelper<CoffeeScript>(new ObjectFactory<CoffeeScript>() {
        @Override
        public CoffeeScript create() {
          return newCoffeeScript();
        }
      });
    }
  
    /**
     * {@inheritDoc}
     */
    @Override
    public void process(final Resource resource, final Reader reader, final Writer writer)
      throws IOException {
      final String content = IOUtils.toString(reader);
      final CoffeeScript coffeeScript = enginePool.getObject();
      try {
        writer.write(coffeeScript.compile(content));
      } catch (final Exception e) {
        onException(e);
        final String resourceUri = resource == null ? StringUtils.EMPTY : "[" + resource.getUri() + "]";
        LOG.error("Exception while applying " + getClass().getSimpleName() + " processor on the " + resourceUri
            + " resource, no processing applied...", e);
      } finally {
        reader.close();
        writer.close();
        enginePool.returnObject(coffeeScript);
      }
    }
  
    /**
     * Invoked when a processing exception occurs.
     */
    protected void onException(final Exception e) {
      throw WroRuntimeException.wrap(e);
    }
  
    /**
     * @return the {@link CoffeeScript} engine implementation. Override it to provide a different version of the coffeeScript.js
     *         library. Useful for upgrading the processor outside the wro4j release.
     */
    protected CoffeeScript newCoffeeScript() {
      return new CoffeeScript();
    }
  
  
    /**
     * {@inheritDoc}
     */
    @Override
    public void process(final Reader reader, final Writer writer)
      throws IOException {
      process(null, reader, writer);
    }
  
    @Override
    public void destroy() throws Exception {
      enginePool.destroy();
    }
  }
  