/*
 * Copyright 2005-2014 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.ws.client.support;

import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;

import org.springframework.beans.factory.InitializingBean;
import org.springframework.util.Assert;
import org.springframework.ws.WebServiceMessageFactory;
import org.springframework.ws.transport.WebServiceConnection;
import org.springframework.ws.transport.WebServiceMessageSender;
import org.springframework.xml.transform.TransformerObjectSupport;

/**
 * Base class for {@code WebServiceTemplate} and other WS-accessing helpers. Defines common properties like the
 * {@link WebServiceMessageFactory} and {@link WebServiceMessageSender}.
 *
 * <p>Not intended to be used directly. See {@link org.springframework.ws.client.core.WebServiceTemplate}.
 *
 * @author Arjen Poutsma
 * @see org.springframework.ws.client.core.WebServiceTemplate
 * @since 1.0.0
 */
public abstract class WebServiceAccessor extends TransformerObjectSupport implements InitializingBean {

	private WebServiceMessageFactory messageFactory;

	private WebServiceMessageSender[] messageSenders;

	/** Returns the message factory used for creating messages. */
	public WebServiceMessageFactory getMessageFactory() {
		return messageFactory;
	}

	/** Sets the message factory used for creating messages. */
	public void setMessageFactory(WebServiceMessageFactory messageFactory) {
		this.messageFactory = messageFactory;
	}

	/** Returns the message senders used for sending messages. */
	public WebServiceMessageSender[] getMessageSenders() {
		return messageSenders;
	}

	/**
	 * Sets the single message sender used for sending messages.
	 *
	 * <p>This message sender will be used to resolve an URI to a {@link WebServiceConnection}.
	 *
	 * @see #createConnection(URI)
	 */
	public void setMessageSender(WebServiceMessageSender messageSender) {
		Assert.notNull(messageSender, "'messageSender' must not be null");
		messageSenders = new WebServiceMessageSender[]{messageSender};
	}

	/**
	 * Sets the message senders used for sending messages.
	 *
	 * <p>These message senders will be used to resolve an URI to a {@link WebServiceConnection}.
	 *
	 * @see #createConnection(URI)
	 */
	public void setMessageSenders(WebServiceMessageSender[] messageSenders) {
		Assert.notEmpty(messageSenders, "'messageSenders' must not be empty");
		this.messageSenders = messageSenders;
	}

	@Override
	public void afterPropertiesSet() {
		Assert.notNull(getMessageFactory(), "Property 'messageFactory' is required");
		Assert.notEmpty(getMessageSenders(), "Property 'messageSenders' is required");
	}

	/**
	 * Creates a connection to the given URI, or throws an exception when it cannot be resolved.
	 *
	 * <p>Default implementation iterates over all configured {@link WebServiceMessageSender} objects, and calls {@link
	 * WebServiceMessageSender#supports(URI)} for each of them. If the sender supports the parameter URI, it creates a
	 * connection using {@link WebServiceMessageSender#createConnection(URI)} .
	 *
	 * @param uri the URI to open a connection to
	 * @return the created connection
	 * @throws IllegalArgumentException when the uri cannot be resolved
	 * @throws IOException				when an I/O error occurs
	 */
	protected WebServiceConnection createConnection(URI uri) throws IOException {
		Assert.notEmpty(getMessageSenders(), "Property 'messageSenders' is required");
		WebServiceMessageSender[] messageSenders = getMessageSenders();
		for (WebServiceMessageSender messageSender : messageSenders) {
			if (messageSender.supports(uri)) {
				WebServiceConnection connection = messageSender.createConnection(uri);
				if (logger.isDebugEnabled()) {
					try {
						logger.debug("Opening [" + connection + "] to [" + connection.getUri() + "]");
					}
					catch (URISyntaxException e) {
						// ignore
					}
				}
				return connection;
			}
		}
		throw new IllegalArgumentException("Could not resolve [" + uri + "] to a WebServiceMessageSender");
	}

}