package org.argeo.cms.ui.util;
   
   import java.io.ByteArrayInputStream;
   import java.io.ByteArrayOutputStream;
   import java.io.IOException;
   import java.io.InputStream;
   import java.net.URL;
   import java.util.LinkedHashMap;
   import java.util.Map;
  
  import org.apache.commons.io.IOUtils;
  import org.argeo.cms.CmsException;
  import org.eclipse.rap.rwt.service.ResourceLoader;
  import org.osgi.framework.Bundle;
  
  /** {@link ResourceLoader} caching stylesheets. */
  public class StyleSheetResourceLoader implements ResourceLoader {
  	private Bundle themeBundle;
  	private Map<String, StyleSheet> stylesheets = new LinkedHashMap<String, StyleSheet>();
  
  	public StyleSheetResourceLoader(Bundle themeBundle) {
  		this.themeBundle = themeBundle;
  	}
  
  	@Override
  	public InputStream getResourceAsStream(String resourceName) throws IOException {
  		if (!stylesheets.containsKey(resourceName)) {
  			// TODO deal with other bundles
  			// Bundle bundle = bundleContext.getBundle();
  			// String location =
  			// bundle.getLocation().substring("initial@reference:".length());
  			// if (location.startsWith("file:")) {
  			// Path path = null;
  			// try {
  			// path = Paths.get(new URI(location));
  			// } catch (URISyntaxException e) {
  			// e.printStackTrace();
  			// }
  			// if (path != null) {
  			// Path resourcePath = path.resolve(resourceName);
  			// if (Files.exists(resourcePath))
  			// return Files.newInputStream(resourcePath);
  			// }
  			// }
  
  			URL res = themeBundle.getEntry(resourceName);
  			if (res == null)
  				throw new CmsException(
  						"Entry " + resourceName + " not found in bundle " + themeBundle.getSymbolicName());
  			ByteArrayOutputStream out = new ByteArrayOutputStream();
  			IOUtils.copy(res.openStream(), out);
  			stylesheets.put(resourceName, new StyleSheet(out.toByteArray()));
  		}
  		return new ByteArrayInputStream(stylesheets.get(resourceName).getData());
  		// return res.openStream();
  	}
  
  	private class StyleSheet {
  		private byte[] data;
  
  		public StyleSheet(byte[] data) {
  			super();
  			this.data = data;
  		}
  
  		public byte[] getData() {
  			return data;
  		}
  
  	}
  }