/*
 * 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.soap.server.endpoint.interceptor;

import java.util.Locale;
import javax.xml.namespace.QName;
import javax.xml.transform.TransformerException;

import org.xml.sax.SAXParseException;

import org.springframework.ws.context.MessageContext;
import org.springframework.ws.server.endpoint.interceptor.AbstractValidatingInterceptor;
import org.springframework.ws.soap.SoapBody;
import org.springframework.ws.soap.SoapFault;
import org.springframework.ws.soap.SoapFaultDetail;
import org.springframework.ws.soap.SoapFaultDetailElement;
import org.springframework.ws.soap.SoapMessage;

/**
 * Subclass of {@code AbstractValidatingInterceptor} that creates a SOAP Fault whenever the request message cannot
 * be validated. The contents of the SOAP Fault can be specified by setting the {@code addValidationErrorDetail},
 * {@code faultStringOrReason}, or	{@code detailElementName} properties. Further customizing can be
 * accomplished by overriding {@code handleRequestValidationErrors}.
 *
 * @author Arjen Poutsma
 * @see #setAddValidationErrorDetail(boolean)
 * @see #setFaultStringOrReason(String)
 * @see #DEFAULT_FAULTSTRING_OR_REASON
 * @see #setDetailElementName(javax.xml.namespace.QName)
 * @see #DEFAULT_DETAIL_ELEMENT_NAME
 * @see #handleResponseValidationErrors(org.springframework.ws.context.MessageContext,org.xml.sax.SAXParseException[])
 * @since 1.0.0
 */
public abstract class AbstractFaultCreatingValidatingInterceptor extends AbstractValidatingInterceptor {

	/**
	 * Default SOAP Fault Detail name used when a validation errors occur on the request.
	 *
	 * @see #setDetailElementName(javax.xml.namespace.QName)
	 */
	public static final QName DEFAULT_DETAIL_ELEMENT_NAME =
			new QName("http://springframework.org/spring-ws", "ValidationError",
					"spring-ws");

	/**
	 * Default SOAP Fault string used when a validation errors occur on the request.
	 *
	 * @see #setFaultStringOrReason(String)
	 */
	public static final String DEFAULT_FAULTSTRING_OR_REASON = "Validation error";

	private boolean addValidationErrorDetail = true;

	private QName detailElementName = DEFAULT_DETAIL_ELEMENT_NAME;

	private String faultStringOrReason = DEFAULT_FAULTSTRING_OR_REASON;

	private Locale faultStringOrReasonLocale = Locale.ENGLISH;

	/**
	 * Returns whether a SOAP Fault detail element should be created when a validation error occurs. This detail element
	 * will contain the exact validation errors. It is only added when the underlying message is a
	 * {@code SoapMessage}. Defaults to {@code true}.
	 *
	 * @see org.springframework.ws.soap.SoapFault#addFaultDetail()
	 */
	public boolean getAddValidationErrorDetail() {
		return addValidationErrorDetail;
	}

	/**
	 * Indicates whether a SOAP Fault detail element should be created when a validation error occurs. This detail
	 * element will contain the exact validation errors. It is only added when the underlying message is a
	 * {@code SoapMessage}. Defaults to {@code true}.
	 *
	 * @see org.springframework.ws.soap.SoapFault#addFaultDetail()
	 */
	public void setAddValidationErrorDetail(boolean addValidationErrorDetail) {
		this.addValidationErrorDetail = addValidationErrorDetail;
	}

	/** Returns the fault detail element name when validation errors occur on the request. */
	public QName getDetailElementName() {
		return detailElementName;
	}

	/**
	 * Sets the fault detail element name when validation errors occur on the request. Defaults to
	 * {@code DEFAULT_DETAIL_ELEMENT_NAME}.
	 *
	 * @see #DEFAULT_DETAIL_ELEMENT_NAME
	 */
	public void setDetailElementName(QName detailElementName) {
		this.detailElementName = detailElementName;
	}

	/** Sets the SOAP {@code faultstring} or {@code Reason} used when validation errors occur on the request. */
	public String getFaultStringOrReason() {
		return faultStringOrReason;
	}

	/**
	 * Sets the SOAP {@code faultstring} or {@code Reason} used when validation errors occur on the request.
	 * It is only added when the underlying message is a {@code SoapMessage}. Defaults to
	 * {@code DEFAULT_FAULTSTRING_OR_REASON}.
	 *
	 * @see #DEFAULT_FAULTSTRING_OR_REASON
	 */
	public void setFaultStringOrReason(String faultStringOrReason) {
		this.faultStringOrReason = faultStringOrReason;
	}

	/** Returns the SOAP fault reason locale used when validation errors occur on the request. */
	public Locale getFaultStringOrReasonLocale() {
		return faultStringOrReasonLocale;
	}

	/**
	 * Sets the SOAP fault reason locale used when validation errors occur on the request.	It is only added when the
	 * underlying message is a {@code SoapMessage}. Defaults to English.
	 *
	 * @see java.util.Locale#ENGLISH
	 */
	public void setFaultStringOrReasonLocale(Locale faultStringOrReasonLocale) {
		this.faultStringOrReasonLocale = faultStringOrReasonLocale;
	}

	/**
	 * Template method that is called when the request message contains validation errors. This implementation logs all
	 * errors, returns {@code false}, and creates a {@link SoapBody#addClientOrSenderFault(String,Locale) client or
	 * sender} {@link SoapFault}, adding a {@link SoapFaultDetail} with all errors if the
	 * {@code addValidationErrorDetail} property is {@code true}.
	 *
	 * @param messageContext the message context
	 * @param errors		 the validation errors
	 * @return {@code true} to continue processing the request, {@code false} (the default) otherwise
	 */
	@Override
	protected boolean handleRequestValidationErrors(MessageContext messageContext, SAXParseException[] errors)
			throws TransformerException {
		for (SAXParseException error : errors) {
			logger.warn("XML validation error on request: " + error.getMessage());
		}
		if (messageContext.getResponse() instanceof SoapMessage) {
			SoapMessage response = (SoapMessage) messageContext.getResponse();
			SoapBody body = response.getSoapBody();
			SoapFault fault = body.addClientOrSenderFault(getFaultStringOrReason(), getFaultStringOrReasonLocale());
			if (getAddValidationErrorDetail()) {
				SoapFaultDetail detail = fault.addFaultDetail();
				for (SAXParseException error : errors) {
					SoapFaultDetailElement detailElement = detail.addFaultDetailElement(getDetailElementName());
					detailElement.addText(error.getMessage());
				}
			}
		}
		return false;
	}
}