package org.paneris.bibliomania;

 import java.io.File;

 import java.io.FileInputStream;

 import java.sql.Timestamp;

 import javax.servlet.ServletConfig;

 import javax.servlet.ServletException;

 import javax.servlet.ServletOutputStream;

 import org.melati.Melati;

 import org.melati.poem.AccessPoemException;

 import org.melati.poem.AccessToken;

 import org.melati.poem.Capability;

 import org.melati.poem.PoemTask;

 import org.melati.poem.PoemThread;

 import org.melati.PoemContext;

 import org.melati.servlet.TrappedException;

 import org.melati.template.TemplateContext;

 import org.melati.template.TemplateEngine;

 import org.melati.template.TemplateEngineException;

 import org.melati.util.MelatiRuntimeException;

 import org.melati.poem.util.StringUtils;

 public class DownloadFile extends org.melati.servlet.ConfigServlet {

   /**

    * 

    */

   private static final long serialVersionUID = 1L;

   // the template engine

   protected TemplateEngine templateEngine;

   /**

    * Inititialise WebMacro

    * @param config

    */

   public void init(ServletConfig config) throws ServletException {

     super.init(config);

     try {

       templateEngine = melatiConfig.getTemplateEngine();

       if (templateEngine != null)

         templateEngine.init(melatiConfig);

     } catch (TemplateEngineException e) {

       // log it to system.err as ServletExceptions go to the

       // servlet runner log (eg jserv.log), and don't have a stack trace!

       e.printStackTrace(System.err);

       throw new ServletException(e.toString());

     }

   }

   protected void doConfiguredRequest(final Melati melatiIn)

     throws Exception {

     melatiIn.setTemplateEngine(templateEngine);

     TemplateContext templateContext =

                       templateEngine.getTemplateContext();

     melatiIn.setTemplateContext(templateContext);

     final DownloadWrapper downloadWrapper = new DownloadWrapper();

     try {

       melatiIn.getDatabase().inSession (

         AccessToken.root, new PoemTask() {

           public void run () {

             try {

               Melati melati =

                 melatiIn.getConfig().getAccessHandler().establishUser(melatiIn);

               try {

                 downloadWrapper.download = establishUser(melati);

               } catch (Exception e) {

                 handleException (melatiIn, e);

               }

             } catch (DownloadException e) {

               throw (e);

             } catch (Exception e) {

                 error(melatiIn, e);

                 throw new TrappedException(e);

             }

           }

         }

       );

       doDownload(melatiIn, downloadWrapper.download);

       melatiIn.getDatabase().inSession (

         AccessToken.root, new PoemTask() {

           public void run () {

             try {

               Melati melati =

                 melatiIn.getConfig().getAccessHandler().establishUser(melatiIn);

               try {

                 recordDownload(melati, downloadWrapper.download);

               } catch (Exception e) {

                 handleException (melatiIn, e);

               }

             } catch (DownloadException e) {

               throw (e);

             } catch (Exception e) {

                 // we have to log this here, otherwise we loose the stacktrace

                 error(melatiIn, e);

                 throw new TrappedException(e);

             }

           }

         }

       );

     } catch (DownloadException e) {

       error(melatiIn, e, downloadWrapper.download);

     }

   }

   public DownloadItem establishUser(Melati melati) 

          throws AccessPoemException, DownloadException {

     DownloadItem download = new DownloadItem();

     BibliomaniaDatabase db = (BibliomaniaDatabase) melati.getDatabase();

     String pathInfo = melati.getRequest().getPathInfo();

     String filename = pathInfo.substring(pathInfo.lastIndexOf("/")+1);

     download.filename = filename;

     Capability registeredUser = db.getRegisteredUserCapability();

     AccessToken token = PoemThread.accessToken();

     if (!token.givesCapability(registeredUser)) {

       throw new AccessPoemException(token, registeredUser);

     } else {

       Download document = (Download)db.getDownloadTable().getFilenameColumn().firstWhereEq(filename);

       download.document = document;

       if (document == null) {

         throw new DownloadException("Sorry, the requested Document (" + filename + ") does not exist.  Please contact <a href='mailto:help@bibliomania.com'>Bibliomania.com</a> so that this problem can be corrected.");

       } else {        

         // check we have purchased this doc

         if (!((User)melati.getUser()).hasPurchased(document.getTroid())) {

           throw new DownloadException("You have not purchased the requested Document, click <a href=org.paneris.ftc365.controller.Account>here</a> to buy more Modules.");

         } else {

           File file = new File(db.getSettingTable().get("filepath") + filename);

 //          File file = new File(filename);

           download.file = file;

           if (!file.exists()) {

             throw new DownloadException("Sorry, the requested file (" + file.getPath() + ") has not been found, please contact mailto:help@bibliomania.com'>Bibliomania.com</a>,  so that this problem can be corrected.");

           }

         }

       }

     }

     return download;

   }

   public void doDownload(Melati melati, DownloadItem download) throws Exception {

       FileInputStream filein = new FileInputStream(download.file);

       melati.getResponse().setContentLength(new Long(download.file.length()).intValue());

       if (download.filename.endsWith("pdf")) {

         melati.getResponse().setContentType("application/pdf");

       } else {

         melati.getResponse().setContentType("application");

       }            

       ServletOutputStream os = melati.getResponse().getOutputStream();

       int i = 0;

       byte[] bbuf = new byte[10000];

       while (i != -1) {

         i = filein.read(bbuf, 0, 10000);

         if (i > -1) os.write(bbuf, 0, i);

       }

   }

   public void recordDownload(Melati melati, DownloadItem downloaditem) {

     BibliomaniaDatabase db = (BibliomaniaDatabase)melati.getDatabase();

     // make record of download

     DownloadEvent downloadEvent = (DownloadEvent)db.getDownloadEventTable()

                                   .newPersistent();

     downloadEvent.setUser((User)melati.getUser());

     downloadEvent.setDocument(downloaditem.document);

     downloadEvent.setDate(new Timestamp((new java.util.Date()).getTime()));

     downloadEvent.getDownloadEventTable().create(downloadEvent);

   }

   public void error(Melati melati, Exception e, DownloadItem download) {

     try {

       TemplateContext templateContext = melati.getTemplateContext();

       templateContext.put("melati",melati);

       templateContext.put("exception", e);

       templateContext.put("download", download);

       String templateName = "DownloadFail.wm";

       templateEngine.expandTemplate(melati.getWriter(), 

                                     templateName,

                                     templateContext);

     } catch (Exception f) {

       f.printStackTrace(System.err);

     }

   }

   protected PoemContext melatiContext(Melati melati) {

      PoemContext it = new PoemContext();

      String[] parts = melati.getPathInfoParts();

      if (parts.length > 0)

       it.setMethod(StringUtils.nulled(parts[parts.length - 1]));

     it.setLogicalDatabase("bibliomania");

     return it;

   }

   public String getSysAdminName() {

     return "TimP";

   }

   public String getSysAdminEmail() {

     return "timp@paneris.org";

   }

   // default method to handle an exception withut a template engine

   protected void handleException(Melati melati, Exception exception)

                  throws Exception {

     if (exception instanceof AccessPoemException) {

       melati.getConfig().getAccessHandler()

         .handleAccessException(melati,(AccessPoemException)exception);

     }

     else

       throw exception;

   }

   public class DownloadException extends MelatiRuntimeException {

     /**

      * 

      */

     private static final long serialVersionUID = 1L;

     public DownloadException(String message) {

       super(message,null);

     }

   }

   private class DownloadWrapper {

     DownloadItem download;

   }

   private class DownloadItem {

     String filename;

     File file;

     Download document;

   }

 }