/*
 * Copyright 2005-2010 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.soap.server.endpoint;

import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Properties;

import org.springframework.util.CollectionUtils;

/**
 * Exception resolver that allows for mapping exception class names to SOAP Faults. The mappings are set using the
 * {@code exceptionMappings} property, the format of which is documented in {@link SoapFaultDefinitionEditor}.
 *
 * @author Arjen Poutsma
 * @since 1.0.0
 */
public class SoapFaultMappingExceptionResolver extends AbstractSoapFaultDefinitionExceptionResolver {

	private Map<String, String> exceptionMappings = new LinkedHashMap<String, String>();

	/**
	 * Set the mappings between exception class names and SOAP Faults. The exception class name can be a substring, with
	 * no wildcard support at present.
	 *
	 * <p>The values of the given properties object should use the format described in
	 * {@code SoapFaultDefinitionEditor}.
	 *
	 * <p>Follows the same matching algorithm as {@code SimpleMappingExceptionResolver}.
	 *
	 * @param mappings exception patterns (can also be fully qualified class names) as keys, fault definition texts as
	 *				   values
	 * @see SoapFaultDefinitionEditor
	 */
	public void setExceptionMappings(Properties mappings) {
		for (Map.Entry<Object, Object> entry : mappings.entrySet()) {
			if (entry.getKey() instanceof String && entry.getValue() instanceof String) {
				exceptionMappings.put((String)entry.getKey(), (String)entry.getValue());
			}
		}
	}

	@Override
	protected SoapFaultDefinition getFaultDefinition(Object endpoint, Exception ex) {
		if (!CollectionUtils.isEmpty(exceptionMappings)) {
			String definitionText = null;
			int deepest = Integer.MAX_VALUE;
			for (String exceptionMapping : exceptionMappings.keySet()) {
				int depth = getDepth(exceptionMapping, ex);
				if (depth >= 0 && depth < deepest) {
					deepest = depth;
					definitionText = exceptionMappings.get(exceptionMapping);
				}
			}
			if (definitionText != null) {
				SoapFaultDefinitionEditor editor = new SoapFaultDefinitionEditor();
				editor.setAsText(definitionText);
				return (SoapFaultDefinition) editor.getValue();
			}
		}
		return null;
	}

	/**
	 * Return the depth to the superclass matching. {@code 0} means ex matches exactly. Returns {@code -1} if
	 * there's no match. Otherwise, returns depth. Lowest depth wins.
	 *
	 * <p>Follows the same algorithm as RollbackRuleAttribute, and SimpleMappingExceptionResolver
	 */
	protected int getDepth(String exceptionMapping, Exception ex) {
		return getDepth(exceptionMapping, ex.getClass(), 0);
	}

	@SuppressWarnings("unchecked")
	private int getDepth(String exceptionMapping, Class<? extends Exception> exceptionClass, int depth) {
		if (exceptionClass.getName().indexOf(exceptionMapping) != -1) {
			return depth;
		}
		if (exceptionClass.equals(Throwable.class)) {
			return -1;
		}
		return getDepth(exceptionMapping, (Class<? extends Exception>) exceptionClass.getSuperclass(), depth + 1);
	}

}