package ca.uhn.hl7v2.hoh.encoder;
   
   import static ca.uhn.hl7v2.hoh.util.StringUtils.*;
   
   import java.io.IOException;
   import java.io.InputStream;
   
   import ca.uhn.hl7v2.hoh.api.DecodeException;
   
  public class Hl7OverHttpResponseDecoder extends AbstractHl7OverHttpDecoder {
  
  	private static final org.slf4j.Logger ourLog = org.slf4j.LoggerFactory.getLogger(Hl7OverHttpResponseDecoder.class);
  	private String myActionLine;
  
  	@Override
  	protected String readActionLineAndDecode(InputStream theInputStream) throws IOException, NoMessageReceivedException, DecodeException {
  		ourLog.trace("Entering readActionLineAndDecode(InputStream)");
  
  		if (myActionLine == null) {
  			String firstLine = readFirstLine(theInputStream);
  			if (firstLine == null || isBlank(firstLine)) {
  				throw new NoMessageReceivedException();
  			}
  
  			if (!firstLine.startsWith("HTTP/1.1 ")) {
  				throw new DecodeException("HTTP response begins with unknown HTTP version. Line is: " + firstLine);
  			}
  
  			String statusPart = firstLine.substring(9);
  			int spaceIdx = statusPart.indexOf(' ');
  			if (spaceIdx == -1) {
  				throw new DecodeException("Invalid response line, no space after status code. Line is: " + firstLine);
  			}
  
  			String statusCode = statusPart.substring(0, spaceIdx);
  			try {
  				setResponseStatus(Integer.parseInt(statusCode));
  			} catch (NumberFormatException e) {
  				throw new DecodeException("Invalid response line. Bad status code: " + statusCode);
  			}
  
  			setResponseName(statusPart.substring(spaceIdx).trim());
  			myActionLine = firstLine;
  			ourLog.trace("Action line is {}", myActionLine);
  
  		} else {
  			ourLog.trace("Already have an action line");
  		}
  		
  		return myActionLine;
  	}
  
  	@Override
  	protected void authorize() throws AuthorizationFailureException {
  		// responses do not need authorization
  	}
  
  	/**
  	 * Returns true if the connection=close header was present in the response
  	 */
  	@Override
  	public boolean isConnectionCloseHeaderPresent() {
  		return super.isConnectionCloseHeaderPresent();
  	}
  
  }