/*
Wotonomy: OpenStep design patterns for pure Java applications.
Copyright (C) 2001 Intersect Software Corporation

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, see http://www.gnu.org
*/

package net.wotonomy.web.xml;

import java.io.BufferedInputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileNotFoundException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.InvocationTargetException;
import java.net.URL;
import java.net.URLConnection;

import net.wotonomy.foundation.NSSelector;
import net.wotonomy.foundation.internal.WotonomyException;

/**
 * An NSSelector customized to invoke methods with XMLRPC when a URL is passed
 * in as the object to the invoke() method. The method name and parameters will
 * be marshalled and sent as an XMLRPC request to the host specified by the URL.
 * <br>
 * <br>
 *
 * To use this class simply as an XMLRPC client, just call invoke() with a URL
 * referencing the XMLRPC server and an optional array of parameters.
 *
 * @author michael@mpowers.net
 * @author $Author: cgruber $
 * @version $Revision: 905 $
 */
public class XMLRPCSelector extends NSSelector {
	private boolean copyStream = false;

	/**
	 * Constructor specifying a method name.
	 */
	public XMLRPCSelector(String aMethodName) {
		super(aMethodName, EMPTY_CLASS_ARRAY);
	}

	/**
	 * Constructor specifying a method name and an array of parameter types. When
	 * accessing XMLRPC servers, invoke() does require that the specified objects
	 * match the types in the parameter type array.
	 */
	public XMLRPCSelector(String aMethodName, Class[] aParameterTypeArray) {
		super(aMethodName, aParameterTypeArray);
	}

	/**
	 * Invokes this selector's method on the specified object using the specified
	 * parameters.
	 */
	public Object invoke(Object anObject, Object[] parameters)
			throws IllegalAccessException, IllegalArgumentException, InvocationTargetException, NoSuchMethodException {
		if (anObject instanceof URL) {
			Receiver receiver = new Receiver();
			byte[] copyOfResponse = null;
			try {
				URLConnection cn = ((URL) anObject).openConnection();

				// set properties
				cn.setDoOutput(true);
				cn.setDoInput(true);
				cn.setRequestProperty("content-type", "text/xml");

				// send parameters
				OutputStream out = cn.getOutputStream();
				new XMLRPCEncoder().encodeRequest(name(), parameters, out);
				out.flush();
				out.close();

				// get response: getInputStream initiates the request
				InputStream input = new BufferedInputStream(cn.getInputStream());
				if (copyStream) {
					ByteArrayOutputStream byteArray = new ByteArrayOutputStream();
					int b;
					while ((b = input.read()) != -1) {
						byteArray.write(b);
					}
					copyOfResponse = byteArray.toByteArray();
					input = new ByteArrayInputStream(copyOfResponse);
				}
				new XMLRPCDecoder().decode(input, receiver);
			} catch (FileNotFoundException exc) {
				throw new WotonomyException("Server did not return a response.");
			} catch (Exception exc) {
				if (copyOfResponse != null) {
					System.out.println(new String(copyOfResponse));
					exc.printStackTrace();
				}
				throw new InvocationTargetException(exc);
			}

			if (receiver.faultString == null) {
				return receiver.result;
			} else {
				throw new InvocationTargetException(
						new WotonomyException(receiver.faultCode + ": " + receiver.faultString));
			}
		}

		// else: not a URL
		return super.invoke(anObject, parameters);
	}

	public static Object invoke(String methodName, Class[] parameterTypes, Object anObject, Object[] parameters)
			throws IllegalAccessException, IllegalArgumentException, InvocationTargetException, NoSuchMethodException {
		return new XMLRPCSelector(methodName, parameterTypes).invoke(anObject, parameters);
	}

	public static Object invoke(String methodName, Object anObject)
			throws IllegalAccessException, IllegalArgumentException, InvocationTargetException, NoSuchMethodException {
		return XMLRPCSelector.invoke(methodName, EMPTY_CLASS_ARRAY, anObject, EMPTY_OBJECT_ARRAY);
	}

	public static Object invoke(String methodName, Class[] parameterTypes, Object anObject, Object aParameter)
			throws IllegalAccessException, IllegalArgumentException, InvocationTargetException, NoSuchMethodException {
		return XMLRPCSelector.invoke(methodName, parameterTypes, anObject, new Object[] { aParameter });
	}

	public static Object invoke(String methodName, Class[] parameterTypes, Object anObject, Object p1, Object p2)
			throws IllegalAccessException, IllegalArgumentException, InvocationTargetException, NoSuchMethodException {
		return XMLRPCSelector.invoke(methodName, parameterTypes, anObject, new Object[] { p1, p2 });
	}

	private class Receiver implements XMLRPCReceiver {
		public Object result;
		public int faultCode;
		public String faultString;

		public Receiver() {
			result = null;
			faultCode = -1;
			faultString = null;
		}

		public void request(String aMethodName, Object[] aParameterArray) {
			throw new WotonomyException("Invalid response: Expected response but received request.");
		}

		public void response(Object aResult) {
			result = aResult;
			faultCode = -1;
			faultString = null;
		}

		public void fault(int aFaultCode, String aFaultString) {
			result = null;
			faultCode = aFaultCode;
			faultString = aFaultString;
		}
	}

}

/*
 * $Log$ Revision 1.1 2006/02/19 01:44:03 cgruber Add xmlrpc files Remove jclark
 * and replace with dom4j and javax.xml.sax stuff Re-work dependencies and
 * imports so it all compiles.
 *
 * Revision 1.1 2006/02/16 13:22:22 cgruber Check in all sources in
 * eclipse-friendly maven-enabled packages.
 *
 * Revision 1.1 2001/02/07 19:24:28 mpowers Moved XML classes to separate
 * package.
 *
 *
 */