package uk.ac.ebi.intenz.webapp.controller;
   
   import java.io.IOException;
   import java.sql.SQLException;
   import java.util.List;
   import java.util.Map;
   import java.util.PropertyResourceBundle;
   
   import javax.servlet.ServletContext;
  import javax.servlet.ServletException;
  
  import org.apache.log4j.Logger;
  
  import uk.ac.ebi.intenz.domain.enzyme.EnzymeEntry;
  import uk.ac.ebi.intenz.domain.exceptions.DomainException;
  import uk.ac.ebi.intenz.webapp.utilities.IntEnzMessenger;
  import uk.ac.ebi.rhea.mapper.MapperException;
  
  /**
   * This command handles requests about proposed entries.
   * <p/>
   * At the moment only requests for the whole list are processed.
   * 
   * @author Michael Darsow
   * @version 0.9 - 21-July-2003
   */
  public class SearchProposedCommand extends DatabaseCommand {
  
  	public static final Logger LOGGER = Logger
  			.getLogger(SearchProposedCommand.class);
  
  	/**
  	 * TBD
  	 * 
  	 * @throws ServletException
  	 * @throws IOException
  	 */
  	public void process() throws ServletException, IOException {
  		String id = request.getParameter("id");
  
  		if (id == null) {
  			List<?> proposedEntries = findProposedList();
  			if (proposedEntries.size() == 0) {
  				request.setAttribute("message",
  						"There are no proposed entries stored in the database at the moment.");
  			}
  			request.setAttribute("proposed", proposedEntries);
  			forward("/proposed.jsp");
  		} else {
  			EnzymeEntry proposedEntry = findProposedEntry(new Long(id));
  			if (proposedEntry != null) {
  				request.setAttribute("result", proposedEntry);
  				forward("/entry.jsp");
  			} else {
  				if (request.getAttribute("message") != null) {
  					forward("/error.jsp");
  				} else {
  					request.setAttribute("message",
  							"The requested proposed entry does not exist.");
  					forward("/error.jsp"); // No result found.
  				}
  			}
  		}
  	}
  
  	// ------------------- PRIVATE METHODS ------------------------
  
  	/**
  	 * Returns the list of all proposed entries.
  	 * <p/>
  	 * The method returns <code>null</code> if an error occured or no entries
  	 * have been found.
  	 * 
  	 * @return the list of proposed entries or <code>null</code> if an error
  	 *         occured.
  	 */
  	private List<EnzymeEntry> findProposedList() {
  		ServletContext application = request.getSession().getServletContext();
  		@SuppressWarnings("unchecked")
  		List<EnzymeEntry> proposedList = (List<EnzymeEntry>) application
  				.getAttribute("proposedList");
  
  		if (proposedList == null) {
  			try {
  				proposedList = enzymeEntryMapper.findProposedList(con);
  				if (proposedList != null) {
  					application.setAttribute("proposedList", proposedList);
  				}
  			} catch (DomainException e) {
  				LOGGER.error("Finding proposed list", e);
  				PropertyResourceBundle intenzMessages = (PropertyResourceBundle) request
  						.getSession().getServletContext()
  						.getAttribute("intenz.messages");
  				IntEnzMessenger.sendError(this.getClass().toString(),
  						intenzMessages.getString(e.getMessageKey()),
  						(String) request.getSession().getAttribute("user"));
  				request.setAttribute("message", e.getMessage());
  				return null;
  			} catch (Exception e) {
 				LOGGER.error("Finding proposed list", e);
 				IntEnzMessenger.sendError(this.getClass().toString(), e
 						.getMessage(), (String) request.getSession()
 						.getAttribute("user"));
 				request.setAttribute("message", e.getMessage());
 				return null;
 			}
 		}
 
 		return proposedList;
 	}
 
 	/**
 	 * Returns the proposed entry requested by the given ID.
 	 * 
 	 * @param id
 	 *            The enzyme ID of the proposed entry.
 	 * @return The proposed entry or <code>null</code> if an error occured.
 	 */
 	private EnzymeEntry findProposedEntry(Long id) {
 		EnzymeEntry enzymeEntry = null;
 		ServletContext application = request.getSession().getServletContext();
 		@SuppressWarnings("unchecked")
 		Map<Long, EnzymeEntry> proposedEntries = (Map<Long, EnzymeEntry>) application
 				.getAttribute("proposedEntries");
 
 		// Check if object already stored in the cache.
 		if (proposedEntries.containsKey(id)) {
 			enzymeEntry = (EnzymeEntry) proposedEntries.get(id);
 		} else {
 			try {
 				enzymeEntry = enzymeEntryMapper.findById(id, con);
 				if (enzymeEntry != null) {
 					proposedEntries.put(id, enzymeEntry);
 				}
 			} catch (SQLException e) {
 				IntEnzMessenger.sendError(this.getClass().toString(), e
 						.getMessage(), (String) request.getSession()
 						.getAttribute("user"));
 				request.setAttribute("message", e.getMessage());
 			} catch (MapperException e) {
 				IntEnzMessenger.sendError(this.getClass().toString(), e
 						.getMessage(), (String) request.getSession()
 						.getAttribute("user"));
 				request.setAttribute("message", e.getMessage());
 			} catch (DomainException e) {
 				LOGGER.error("Finding proposed entry", e);
 				PropertyResourceBundle intenzMessages = (PropertyResourceBundle) request
 						.getSession().getServletContext()
 						.getAttribute("intenz.messages");
 				IntEnzMessenger.sendError(this.getClass().toString(),
 						intenzMessages.getString(e.getMessageKey()),
 						(String) request.getSession().getAttribute("user"));
 				request.setAttribute("message", e.getMessage());
 			} finally {
 				try {
 					con.close();
 				} catch (SQLException e) {
 					IntEnzMessenger.sendError(this.getClass().toString(), e
 							.getMessage(), (String) request.getSession()
 							.getAttribute("user"));
 					request.setAttribute("message", e.getMessage());
 					return null;
 				}
 			}
 		}
 		return enzymeEntry;
 	}
 }