/* Look for the run method of CommentsConnection class. */

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

public class CommentsServer extends Thread {
  public static final int DEFAULT_PORT = 7777;
  protected int port;
  protected ServerSocket server;
  private static final String driverPrefixURL = "jdbc:odbc:";
  private static String username = null;
  private static String password = null;
  private static String dataSource = null;
  public static String getUsername() {
    return username;
  }
  public static String getPassword() {
    return password;
  }
  public static String getDriverURL() {
    return driverPrefixURL+dataSource;
  }
  public static void main (String args[]) {
    int port=0;
    if (args.length == 1) {
      try {
        port = Integer.parseInt (args[0]);
      } catch (NumberFormatException e) { }
    }
    try {
      Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
    }
    catch (Exception e) {
      System.err.println("Failed to load JDBC/ODBC driver.");
      System.exit (1);
    }
    try {
      // Look for resource file 'odbc.datasource'
      InputStream is = ClassLoader.getSystemResourceAsStream ("odbc.datasource");
      Properties p = new Properties();
      p.load (is);
      dataSource = p.getProperty("datasource.name");
      if (dataSource == null)
        throw new Exception ();
      username = p.getProperty("datasource.username", "");
      password = p.getProperty("datasource.password", "");
    } catch (Exception e) {
      System.err.println("Unable to read resource to get data source");
      System.exit (1);
    }
    new CommentsServer (port);
  }
  public CommentsServer (int port) {
    super ("Comments Server");
    if (port == 0)
      port = DEFAULT_PORT;
    this.port = port;
    try {
      server = new ServerSocket (port);
    } catch (IOException e) {
      System.err.println ("Error creating server");
      System.exit (1);
    }
    start();
  }
  public void run() {
    System.out.println ("Server Running");
    ThreadGroup connections = new ThreadGroup ("Comment Connections");
    connections.setMaxPriority(this.getPriority()-1);
    try {
      while (true) {
        Socket client = server.accept();
        System.out.println ("Connection from: " + client.getInetAddress().getHostName());
        CommentsConnection c = new CommentsConnection (connections, client);
      }
    } catch (IOException e) {
      System.err.println ("Exception listening");
      System.exit (1);
    }
    System.exit (0);
  }
}

class CommentsConnection extends Thread {
  static int counter = 0;
  protected ObjectInputStream in;
  protected PrintWriter out;
  public CommentsConnection (ThreadGroup group, Socket client) {
    super (group, "Connection " + counter++);
    try {
      in = new ObjectInputStream (client.getInputStream ());
      out = new PrintWriter (client.getOutputStream(), true);
    } catch (IOException e) {
      try {
        client.close();
      } catch (IOException e2) { }
      System.err.println ("Unable to connect.");
      return;
    }
    start();
  }

/*
 * Commands are sent to thread across the Socket connection
 * using an ObjectInputStream (Serialization).
 * Results are sent back across the Socket connection
 * using a PrinterWriter, which is functionally equivalent to
 * a PrintStream but works with 16-bit characters.
 * If command is 'insert', three Strings follow representing
 * the name, username, and comments.
 * Send back any error messages in PrintWriter.
 * If command is 'query', just select all from comments table.
 */

  public void run () {
    try {
      String mode = (String)in.readObject();
      if (/* Insert Mode */) {
        // Read in three String objects from 'in' ObjectInputStream.
        // Follow example of 'mode' above.
        try {
          // Create Connection
          // Create Prepared Statement / Statement and fill it up.
          // Execute it and check if it inserted one row
        } catch (Exception e) {
          out.println ("Error updating: " + e);
          return;
        }
      } else if (/* Query Mode */) {
        try {
          // Create Connection
          // Create Statement
          // Execute Statement and get Results
          // Loop through records
        } catch (Exception e) {
          out.println ("Error querying: " + e);
          return;
        }
      } else {
        out.println ("Invalid Command: " + mode);
      }
    } catch (Exception e) {
      out.println ("Error reading Stream: " + e);
    }
    out.close();
  }
}