/*

 * Created on Aug 16, 2003

 */

package isac.util;

import isac.browserdialog.BDialog;

import isac.session.OManager;

import isac.session.SDialog;

import java.io.IOException;

import java.net.MalformedURLException;

import java.rmi.Naming;

import java.rmi.NotBoundException;

import java.rmi.RemoteException;

import java.util.Vector;

import org.apache.xmlrpc.XmlRpcClient;

import org.apache.xmlrpc.XmlRpcException;

/**

 * @author Andreas Griesmayer

 * 

 * The InformationProcessor builds the bridge between BrowserFrontend and

 * BrowserDialog. It encapsulates all tasks regarding communication and connects

 * to the proper dialog-modules.

 * 

 * Because the final communication-protocol is not fixed yet, it provides

 * methods to communicate via RMI as well as XML-RPC

 */

public class InformationProcessor {

	/**

	 * Performes an login on the session dialog using the XML-RPC protocol. It

	 * assumes that the SessionDialog is running its XML-RPC-handler on port

	 * 1050 of the local machine.

	 * 

	 * @param username

	 *            username of the user who wants to login.

	 * @param password

	 *            corresponding password for the user.

	 * @return the id of the current sesson the user logged in or null if the

	 *         login did not succeed

	 * @throws NullPointerException

	 *             carrying the error-message if an communication error occured.

	 */

	static protected String xmlLogin(String username, String password) {

		try {

			XmlRpcClient sdialog = new XmlRpcClient("http://localhost:1050");//WN fixed port

			Vector params = new Vector();

			params.add(username);

			params.add(password);

			Vector response = (Vector) sdialog.execute("SDialog.login", params);

			if (response.size() > 0)

				return (String) response.elementAt(0);

		} catch (MalformedURLException e) {

			throw new NullPointerException(

					getErrorXML("Sorry, MalformedURLException while accessing the SDialog to login - is the SDialog runnig ?"

							+ e.getMessage()));

		} catch (XmlRpcException e) {

			throw new NullPointerException(

					getErrorXML("Sorry, XmlRpcException while accessing the SDialog to login - is the SDialog runnig ?"

							+ e.getMessage()));

		} catch (IOException e) {

			throw new NullPointerException(

					getErrorXML("Sorry, IOException while accessing the SDialog to login - is the SDialog runnig ?"

							+ e.getMessage()));

		}

		return null;

	}

	/**

	 * Performes a login on the Session dialog using RMI. It assumes the

	 * SessionDialog to be found at //localhost/isac-ObjectManager

	 * 

	 * @param username

	 *            username of the user who wants to login.

	 * @param password

	 *            corresponding password for the user.

	 * @return the id of the current sesson the user logged in or null if the

	 *         login did not succeed

	 * @throws NullPointerException

	 *             carrying the error-message if an communication error occured.

	 */

	static public String login(String username, String password) {

		SDialog sd = getSDialog();

		try {

			/* LK 04.08.27 */

			//if username != pwd -> empty Vector

			Vector v = sd.login(username, password);

			if (v.size() == 0) {

				return null;

			} else {

				return (String) v.elementAt(0);

			}

		} catch (RemoteException e) {

			throw new NullPointerException(

					getErrorXML("Sorry, RemoteEcxeption while accessing the SDialog to login - is the SDialog runnig ?"

							+ e.getMessage()));

		}

	}

	public static BDialog getBDialog(String session) {

		String name = "//localhost/isac-ObjectManager";

		try {

			System.out.println("connect to ObjectManager" + name);

			Object lookup = Naming.lookup(name);

			return ((OManager) lookup).getBrowserDialog(session);

		} catch (RemoteException exc) {

			System.err.println("no rmiregistry runing on server " + name

					+ " no connection possible --- try later");

			System.err.println("serverCom exception: " + exc.getMessage());

		} catch (NotBoundException exc) {

			System.err.println("servercom: notboundexc: " + exc.getMessage());

			System.err.println("server not found - try to connect to Proxy");

		} catch (java.net.MalformedURLException exc) {

			System.err.println("servercom: MalformedURLException: "

					+ exc.getMessage());

			exc.printStackTrace();

		}

		return null;

	}

	public static SDialog getSDialog() {

		String name = "//localhost/isac-ObjectManager";

		try {

			System.out.println("connect to ObjectManager: " + name);

			Object lookup = Naming.lookup(name);

			return ((OManager) lookup).getSessionDialog();

		} catch (RemoteException exc) {

			System.err.println("no rmiregistry runing on server " + name

					+ " no connection possible --- try later");

			System.err.println("serverCom exception: " + exc.getMessage());

		} catch (NotBoundException exc) {

			System.err.println("servercom: notboundexc: " + exc.getMessage());

			System.err.println("server not found - try to connect to Proxy");

		} catch (java.net.MalformedURLException exc) {

			System.err.println("servercom: MalformedURLException: "

					+ exc.getMessage());

			exc.printStackTrace();

		}

		return null;

	}

	/*

	 * static protected String oldloadString(String function, Vector parameter){

	 * XmlRpcClient bdialog; String xmlsource=""; try { bdialog = new

	 * XmlRpcClient("http://localhost:1040"); Vector result = (Vector)

	 * bdialog.execute(function, parameter); xmlsource =

	 * (String)result.firstElement(); } catch (MalformedURLException e) {

	 * e.printStackTrace(); } catch (XmlRpcException e) { e.printStackTrace(); }

	 * catch (IOException e) { e.printStackTrace(); } return xmlsource; }

	 */

	/*

	 * static protected Vector oldloadVector(String function, Vector parameter){

	 * Vector return_vect=new Vector(); XmlRpcClient bdialog; String

	 * xmlsource=""; try { bdialog = new XmlRpcClient("http://localhost:1040");

	 * return_vect = (Vector) bdialog.execute(function, parameter); } catch

	 * (MalformedURLException e) { e.printStackTrace(); } catch (XmlRpcException

	 * e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); }

	 * return return_vect; }

	 */

	/**

	 * Loads the hierarchy for the information-type <code>type</type>

	 * @param session session to identify on the SessionDialog

	 * @param type type of the hierarchy to load

	 * @return  the requested hierarchy in its XML-representation, in case of an RemoteException, a XML-code 

	 * carrying the error-message is returned

	 */

	static public String loadHierarchy(String session, String type) {

		BDialog bd = getBDialog(session);

		try {

			return bd.loadHierarchy(type);

		} catch (RemoteException e) {

			return getErrorXML("Sorry, RemoteEcxeption while accessing the BDialog to login - is the BDialog runnig ?"

					+ e.getMessage());

		}

	}

	/**

	 * Loads binary files from the KE-Base

	 * 

	 * @param session

	 *            session to identify on the SessionDialog

	 * @param type

	 *            to identify the location of the binary file. An id has only to

	 *            be unique within a type, although a globally unique id should

	 *            be used.

	 * @param content_id

	 *            Id of the binary-file to load

	 * @return the requested binary-file as byte-array, in case of an

	 *         RemoteException, an empty array is returned

	 */

	static public byte[] loadBinary(String session, String type,

			String content_id) {

		BDialog bd = getBDialog(session);

		try {

			return bd.loadBinary(type, content_id);

		} catch (RemoteException e) {

			return new byte[0];

		}

	}

	static public String loadXML(String session, String type, Vector idvect) {

		BDialog bd = getBDialog(session);

		try {

			return bd.loadContent(type, idvect);

		} catch (RemoteException e) {

			return getErrorXML("Sorry, RemoteException while accessing the BDialog to fetch your content");

		}

	}

	/**

	 * Loads content-files from the KE-Base

	 * 

	 * @param session

	 *            session to identify on the SessionDialog

	 * @param type

	 *            to identify the location of the KE-Object. An id has only to

	 *            be unique within a type, although a globally unique id should

	 *            be used.

	 * @param content_id

	 *            Id of the KE-Object to load

	 * @return the requested KE-Object in its XML-representation, in case of an

	 *         RemoteException, a XML-code carrying the error-message is

	 *         returned

	 */

	static public String loadXML(String session, String type, String content_id) {

		BDialog bd = getBDialog(session);

		try {

			return bd.loadContent(type, content_id);

		} catch (RemoteException e) {

			return getErrorXML("Sorry, RemoteException while accessing the BDialog to fetch your file \""

					+ content_id + "\" is the BDialog running?");

		}

	}

	/**

	 * Evaluates the requested content in the given worksheet using the

	 * BrowserDialog

	 * 

	 * @param session

	 *            session to identify on the SessionDialog

	 * @param type

	 *            to identify the location of the KE-Object. An id has only to

	 *            be unique within a type, although a globally unique id should

	 *            be used.

	 * @param content_id

	 *            Id of the KE-Object to load

	 * @param wd_id

	 *            id of the worksheet the contanct for evaluating

	 * @return the requested KE-Object in its XML-representation, in case of an

	 *         RemoteException, a XML-code carrying the error-message is

	 *         returned

	 * @see BDialog#evaluateContent

	 */

	static public String evaluateXML(String session, String type,

			String content_id, String wd_id) {

		BDialog bd = getBDialog(session);

		try {

			return bd.evaluateContent(type, content_id, wd_id);

		} catch (RemoteException e) {

			return getErrorXML("Sorry, RemoteException while accessing the BDialog to evaluate \""

					+ content_id + "\" is the BDialog running?");

		}

	}

	/*

	 * static protected Reader loadsKEObject(String function, Vector parameter){

	 * XmlRpcClient bdialog; String xmlsource=""; try { bdialog = new

	 * XmlRpcClient("http://localhost:1040"); Vector result = (Vector)

	 * bdialog.execute(function, parameter); if(result.size()>0) xmlsource =

	 * (String)result.firstElement(); else xmlsource = ""; } catch

	 * (MalformedURLException e) { return new StringReader(getErrorXML("Sorry,

	 * MalformedURLException while accessing the KEStore")); } catch

	 * (XmlRpcException e) { return new StringReader(getErrorXML("Sorry,

	 * XmlRpcException while accessing the KEStore")); } catch (IOException e) {

	 * return new StringReader(getErrorXML("Sorry, IOException while accessing

	 * the KEStore")); } return new StringReader(xmlsource); }

	 */

	/**

	 * Get the corresponding user for a session.

	 * 

	 * @param session_id

	 *            id of the session to identify the user

	 * @return username or null if an invalid sessionid was given

	 * @throws NullPointerException

	 *             carrying the error-message if an RemoteException occures.

	 */

	public static String getUsername(String session_id) {

		SDialog sd = getSDialog();

		try {

			String username;

			if ((username = sd.getUsername(session_id)).equals(""))

				return null;

			return username;

		} catch (RemoteException e) {

			throw new NullPointerException(

					getErrorXML("Sorry, RemoteException while accesing the SDialog - is it running ?"));

		}

	}

	/**

	 * @param session_id

	 * @return

	 */

	private static String xmlGetUsername(String session_id) {

		XmlRpcClient bdialog;

		String xmlsource = "";

		Vector parameter = new Vector();

		parameter.add(session_id);

		try {

			bdialog = new XmlRpcClient("http://localhost:1050");

			String result = (String) bdialog.execute("SDialog.getUsername",

					parameter);

			if (result.equals(""))

				return null;

			return result;

		} catch (MalformedURLException e) {

			return getErrorXML("Sorry, MalformedURLException while accesing the SDialog - is it running ?");

		} catch (XmlRpcException e) {

			return getErrorXML("Sorry, XmlRpcException while accesing the SDialog - is it running ?");

		} catch (IOException e) {

			return getErrorXML("Sorry, IOException while accesing the SDialog - is it running ?");

		}

	}

	private static String getErrorXML(String string) {

		return "<ERROR><DESCRIPTION> <h1> Error in file InformationPrecessor.java </h1>"

				+ string + "</DESCRIPTION></ERROR>";

	}

}