/**
 * <copyright> Copyright 2006 by Know-Center, Graz, Austria </copyright>
 * PDF-AS has been contracted by the E-Government Innovation Center EGIZ, a
 * joint initiative of the Federal Chancellery Austria and Graz University of
 * Technology.
 *
 * Licensed under the EUPL, Version 1.1 or - as soon they will be approved by
 * the European Commission - subsequent versions of the EUPL (the "Licence");
 * You may not use this work except in compliance with the Licence.
 * You may obtain a copy of the Licence at:
 * http://www.osor.eu/eupl/
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the Licence is distributed on an "AS IS" basis,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the Licence for the specific language governing permissions and
 * limitations under the Licence.
 *
 * This product combines work with different licenses. See the "NOTICE" text
 * file for details on the various modules and licenses.
 * The "NOTICE" text file is part of the distribution. Any derivative works
 * that you distribute must include a readable copy of the "NOTICE" text file.
 */
package at.gv.egiz.pdfas.web.helper;

import java.io.File;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;

import javax.servlet.ServletContext;

import at.gv.egiz.pdfas.api.PdfAs;
import at.gv.egiz.pdfas.api.internal.PdfAsInternal;
import at.knowcenter.wag.egov.egiz.exceptions.WebException;

/**
 * Utility methods for easier handling of {@link PdfAs} API object.
 * 
 * @author exthex
 *
 */
public class ApiHelper {

   public static final String PDF_AS_OBJECT = "PDF_AS_OBJECT";

   public static final String INTERNAL_PDF_AS_OBJECT = "INTERNAL_PDF_AS_OBJECT";
   
   /**
    * Instantiate the {@link PdfAs} implementation.
    * 
    * @param file config directory
    * @return
    * @throws WebException
    */
   public static PdfAs createApiObject(File file) throws WebException {
      try {
         Class pdfAsClass = Class.forName("at.gv.egiz.pdfas.impl.api.PdfAsObject");
         Constructor constructor = pdfAsClass.getConstructor(new Class[]{File.class});
         PdfAs pdfAs = (PdfAs)constructor.newInstance(new Object[]{
               new File(WebSettingsReader.RESOURCES_PATH)});
         return pdfAs;
      } catch (ClassNotFoundException e) {
         throw new WebException(e);
      } catch (SecurityException e) {
         throw new WebException(e);
      } catch (NoSuchMethodException e) {
         throw new WebException(e);
      } catch (IllegalArgumentException e) {
         throw new WebException(e);
      } catch (InstantiationException e) {
         throw new WebException(e);
      } catch (IllegalAccessException e) {
         throw new WebException(e);
      } catch (InvocationTargetException e) {
         throw new WebException(e);
      }
   }

   /**
    * Instantiate the {@link PdfAsInternal} implementation.
    * 
    * @return
    * @throws WebException
    */
   public static PdfAsInternal createInternalApiObject() throws WebException {
      try {
         Class pdfAsClass = Class.forName("at.gv.egiz.pdfas.impl.api.internal.PdfAsInternalObject");
         PdfAsInternal pdfAsinternal = (PdfAsInternal)pdfAsClass.newInstance();
         return pdfAsinternal;
      } catch (ClassNotFoundException e) {
         throw new WebException(e);
      } catch (SecurityException e) {
         throw new WebException(e);
      } catch (InstantiationException e) {
         throw new WebException(e);
      } catch (IllegalAccessException e) {
         throw new WebException(e);
      }
   }

   /**
    * Retrieve the {@link PdfAs} object from the {@link ServletContext}
    * 
    * @param servletContext
    * @return
    */
   public static PdfAs getPdfAsFromContext(ServletContext servletContext) {
      return (PdfAs)servletContext.getAttribute(PDF_AS_OBJECT);
   }

   /**
    * Retrieve the {@link PdfAsInternal} object from the {@link ServletContext}
    * 
    * @param servletContext
    * @return
    */
   public static PdfAsInternal getPdfAsInternalFromContext(ServletContext servletContext) {
      return (PdfAsInternal)servletContext.getAttribute(INTERNAL_PDF_AS_OBJECT);
   }

}