package uk.ac.ebi.intenz.webapp.controller;
   
   import java.io.IOException;
   import java.sql.SQLException;
   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.mapper.EnzymeEntryMapper;
  import uk.ac.ebi.intenz.webapp.utilities.IntEnzMessenger;
  import uk.ac.ebi.rhea.mapper.MapperException;
  
  /**
   * This command handles enzyme ID requests.
   * 
   * @author Michael Darsow
   * @version 0.9 - 21-July-2003
   */
  public class SearchIDCommand extends DatabaseCommand {
  
  	public static final Logger LOGGER = Logger.getLogger(SearchIDCommand.class);
  
  	/**
  	 * TBD
  	 * 
  	 * @throws ServletException
  	 * @throws IOException
  	 */
  	public void process() throws ServletException, IOException {
  		String id = request.getParameter("id");
  
  		if (id != null) {
  			EnzymeEntry enzymeEntry = findEnzymeEntry(new Long(id));
  			if (enzymeEntry != null) {
  				request.setAttribute("result", enzymeEntry);
  				forward("/entry.jsp");
  			} else {
  				if (request.getAttribute("message") != null) {
  					forward("/error.jsp");
  				} else {
  					request.setAttribute("message",
  							"The enzyme with the given ID: <b>" + id
  									+ "</b> does not exist.");
  					forward("/notFound.jsp"); // No result found.
  				}
  			}
  		} else {
  			request.setAttribute(
  					"message",
  					"The <b>id</b> parameter has to be set to be able to search for an enzyme using its ID.");
  			forward("/error.jsp");
  			return;
  		}
  	}
  
  	// ------------------- PRIVATE METHODS ------------------------
  
  	/**
  	 * Calls the according <code>find()</code> method and handles empty results
  	 * and SQL exceptions.
  	 * 
  	 * @param id
  	 *            ID of the enzyme to search for.
  	 * @return An <code>EnzymeEntry</code> instance or <code>null</code>.
  	 */
  	protected EnzymeEntry findEnzymeEntry(Long id) {
  		EnzymeEntry enzymeEntry = null;
  
  		ServletContext application = request.getSession().getServletContext();
  		@SuppressWarnings("unchecked")
  		Map<Long, EnzymeEntry> entries = (Map<Long, EnzymeEntry>) application
  				.getAttribute("entries_id");
  
  		// Check if object already stored in the cache.
  		if (entries.containsKey(id)) {
  			enzymeEntry = (EnzymeEntry) entries.get(id);
  		} else {
  			try {
  				enzymeEntry = enzymeEntryMapper.findById(id, con);
  				if (enzymeEntry != null) {
  					entries.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("Searching by ID", 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;
 	}
 }