/* introducing... the WebRaveler package ! */
package webraveler.http;

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

/**
 * HTTP message (request or response).
 *
 * @author The Web Raveler Development Squad
 * @version 1.0
 */
public class HTTPMessage implements Serializable {
	/* variables */
	protected Hashtable headers;
	
	/* constructors */
	public HTTPMessage() {
		headers = new Hashtable();
	}
	
	/* methods */
	
	/**
	 * Set a given key-value pair as a header line in the message.
	 *
	 * @param header a string containing the name of the header
	 * @param value a string containing the header field
	 */
	public void addHeader(String header, String value) {
		/* if the header already has a key in the hash table, we want to 
		 * add the new value to the value string after a comma and a space. */
		String oldValue = new String();
		if ( headers.containsKey(header) ) {
			oldValue = (String) headers.get(header.toLowerCase());
			headers.put(header.toLowerCase(), oldValue+", "+value);
		} else {
			headers.put(header.toLowerCase(),value);
		}
	}
	
	
	public void setHeader(String header, String value) {
			headers.put(header.toLowerCase(),value);
	}
	
	
	
	/**
	 * Get the value for a given key String.
	 *
	 * @param header a string containing the name of the header
	 * @return a string containing the header field
	 */
	public String getHeader(String header) {
		if (headers.containsKey(header.toLowerCase()))
			return (String) headers.get(header.toLowerCase());
		else 
			return null;
	}//String getHeader(String)
	
	
	/**
	 * Delete the given header value
	 *
	 * @param header a string containing the name of the header
	 */
	public void deleteHeader(String header) {
		headers.remove(header.toLowerCase());
	}
	
	
	/**
	 * Check whether or not a given header is contained in the headers of the HTTPMessage.
	 *
	 * @param header a string containing the name of the header
	 * @return a boolean indicating whether the header exists 
	 */
	public boolean containsHeader(String header) {
		return headers.containsKey(header.toLowerCase());
		
	}
	
	
	/**
	 * Read a line of input from the given input stream.  (YAY! We actually used some
	 * of Daren's code!  Hooray for us!  Happy happy joy joy!)
	 *
	 * @param in    an inputstream, ostensibly containing text lines
	 */
	public static String readLine(InputStream in) throws IOException {
		StringBuffer buf= new StringBuffer();
		int c= in.read();
		if( c== -1) return null;
		while( c != -1 ){
			if( c=='\r' ){
				in.read();//clear \n
				break;
			}
			if( c=='\n' ){
				break;
			}
			buf.append((char)c);
			c= in.read();
		}
		return buf.toString();
	} 
	
	
	
}