/**
* This file contains example code from the book
* JAVA NETWORKING AND COMMUNICATIONS
* by Todd Courtois
* ISBN 0-13-850454-7
*
* Purchasers of the book may reuse this sample code
* for any purpose whatsoever as long as this header
* is included. Use of this example code is subject
* to the license agreement printed in the book.
*
* For updates see the web site
* http://www.rawthought.com/JNC/
*/

/**
 * Modified by Michael Hicks for CMSC 433,
 * University of Maryland, 2002.
 */

import java.io.*;
import java.net.*;
import java.util.*;

/**
* An object encapsulating an HTTP GET request, for 1.0 or 1.1.
* Ignores the MIME headers.
*/
public class HttpGetRequestSimple extends HttpRequest
{
  public static boolean fDebugOn = true;
  
  public HttpGetRequestSimple(String request, String version, String type) {
    super(request,version,type);
  }
  
  /**
   * Read an HTTP request and return an HttpRequest object on success,
   * or NULL on failure.  On failure, the proper response will be sent
   * to the output stream.  All of the MIME headers are ignored.
   *
   * @param clientInputStream The stream where the client sends us
   *   its request
   * @param clientOutputStream The stream where we return content to
   *   the client
   */
  public static HttpRequest readRequest(InputStream clientInputStream,
                                        OutputStream clientOutputStream)
  {
    /* Parse the first line of the request, getting the filename
     * and HTTP version.  Then call the subhandler's parsing routine. 
     */
    String path;
    String version = "";
    try {
      //gets first line, should contain
      //"GET foo.html HTTP/1.0" (or 1.1)
      DataInputStream in = new DataInputStream(clientInputStream);
      String firstLineStr = in.readLine();
      if (fDebugOn) System.out.println("read line "+firstLineStr);
      StringTokenizer tokSource = new StringTokenizer(firstLineStr);
      
      String curTok = tokSource.nextToken();
      if (fDebugOn) System.out.println("curTok: " + curTok);
      
      // make sure it's a GET request
      if (curTok.equals("GET")) {
        curTok = tokSource.nextToken();
        path = curTok;
        
        //now get the HTTP version
        version = tokSource.nextToken();
        if (fDebugOn) System.out.println("curTok: " + version);

        if (!version.substring(0,4).equals("HTTP")) {
          if (fDebugOn)
            System.out.println("bad request: expecting HTTP/ver");
          path = null;
        }
      }
      else {
        if (fDebugOn) System.out.println("bad request: expecting GET");
        path = null;
      }
    } catch (Exception ex) {
      if (fDebugOn) System.out.println("bad request: got exception "+ex);
      path = null;
    }

    /* Return the request or null if an error, sending a message
     * to the client as well.
     */
    if (path != null) {
      // strip off leading / if one exists
      while (path.length() != 0 && path.charAt(0) == '/') {
	path = path.substring(1);
      }
      return new HttpGetRequestSimple(path, version, "GET");
    }
    else {
      HttpResponse err = HttpResponse.errorResponse("mangled request");
      err.sendResponse(clientOutputStream);
      return null;
    }
  }
}