package com.c2kernel.utils.server;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.Socket;
import java.util.Date;
import java.util.HashMap;
import java.util.NoSuchElementException;
import java.util.StringTokenizer;

import com.c2kernel.utils.Logger;

public class HTTPRequestHandler implements SocketHandler {

    protected HashMap headers = new HashMap();
    protected String method;
    protected String resource;
    protected String version;
    protected String returnMIME;
    protected String statusCode;
    protected String postData;
    protected final static String CRLF = "\r\n";
    protected BufferedReader request;
    protected Socket currentSocket = null;
   
    public HTTPRequestHandler() { }
    
    public String getName() {
        return "HTTP Server";
    }

    public boolean isBusy() {
        return (currentSocket!=null);
    }

    public void setSocket(Socket newSocket) {
        currentSocket = newSocket;
    }
    
    public void shutdown() {
        try {
            if (currentSocket != null) currentSocket.close();
        } catch (IOException e) {
            Logger.error("Error shutting down HTTP connection");
        }
        currentSocket = null;
    }
        
    public void run() {
        Thread.currentThread().setName("HTTP Request Handler");
        try {
            request = new BufferedReader(new InputStreamReader(currentSocket.getInputStream()));    
            // parse the request
            boolean firstLine = true;
            String headerLine;
            do {
                headerLine = request.readLine();
                if (headerLine == null)
                    throw new IOException("Disconnected");
                if (firstLine) { // request line
                    StringTokenizer params = new StringTokenizer(headerLine);
                    try {
                        method = params.nextToken();
                        resource = params.nextToken();
                        version = params.nextToken();
                    } catch (NoSuchElementException ex1) { } // incomplete request line - doesn't matter
                    firstLine = false;
                }
                else { // headers
                    int split = headerLine.indexOf(": ");
                    if (split >= 0) 
                        headers.put(
                            headerLine.substring(0, split),
                            headerLine.substring(split+2)
                            );
                }
            } while (!headerLine.equals(CRLF) && !headerLine.equals(""));

            String response = null;

            try {
                
                if (headers.containsKey("Content-length")) { // read POST data
                    StringBuffer postBuffer = new StringBuffer();
                    int received = 0; int length = Integer.parseInt((String)headers.get("Content-length"));
                    try {
                        while (received < length) {
                            String postLine = request.readLine();
                            postBuffer.append(postLine);
                            received+=postLine.length();
                        }
                    } catch (IOException ex) {
                        Logger.error("Error reading post data. "+received+" bytes of "+length+" received. ("+(received*100.0/length)+"%");
                        Logger.error(ex);
                        throw ex;
                    }
                }
                // Got the params, generate response
                
                returnMIME = "text/xml";
                statusCode = "200 OK";

                response = processRequest();
            } catch (Exception ex3) {
                response = error("500 Server Error", ex3.getClass().getName()+"<br>"+ex3.getMessage());
            }
            System.out.println(new Date().toString()+" "+currentSocket.getInetAddress()+" "+method+" "+resource+" "+statusCode);

            OutputStream output = currentSocket.getOutputStream();
            
            statusCode = "HTTP/1.0 "+statusCode+CRLF;
            output.write(statusCode.getBytes());
            
            returnMIME = "Content-type: "+returnMIME+CRLF;
            output.write(returnMIME.getBytes());
            
            String contentLength = "Content-Length: "+response.length()+CRLF;
            output.write(contentLength.getBytes());
            
            // Possible: last mod?
            // end of headers
            output.write(CRLF.getBytes());
            
            // write the content
            output.write(response.getBytes());
            request.close();
            output.close();
            currentSocket.close();
        } catch (IOException ex2) { 
            Logger.error(ex2);
        } // aborted connection probably
        currentSocket = null;
    }
    
    /* This is a dummy method that doesn't support anything.
     * Override it.
     */
    
    public String processRequest() {
        return error("501 Not Implemented", "The method "+method+" you have requested is not supported by this server.");
    }
    
    public String error(String code, String desc) {
        statusCode = code;
        returnMIME = "text/html";
        return ("<HTML>" + 
            "<HEAD><TITLE>"+code+"</TITLE></HEAD>" +
            "<BODY><h1>"+code+"</h1>" +
            "<p>"+desc+
            "<hr><p><small>Cristal Item HTTP server</small></BODY></HTML>");
    }
}