/**
 * Licensed to Apereo under one or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information regarding copyright ownership. Apereo
 * licenses this file to you 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 the
 * following location:
 *
 * <p>http://www.apache.org/licenses/LICENSE-2.0
 *
 * <p>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.apereo.portal.rendering;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.xml.namespace.QName;
import javax.xml.stream.XMLEventFactory;
import javax.xml.stream.events.Attribute;
import javax.xml.stream.events.StartElement;
import org.apereo.portal.utils.cache.CacheKey;

/**
 */
public class StaticAttributeSource implements AttributeSource {
    private final XMLEventFactory xmlEventFactory = XMLEventFactory.newFactory();

    private Map<String, Map<String, String>> attributes;

    public void setAttributes(Map<String, Map<String, String>> attributes) {
        this.attributes = attributes;
    }

    /* (non-Javadoc)
     * @see org.apereo.portal.rendering.AttributeSource#getAdditionalAttributes(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse, javax.xml.stream.events.StartElement)
     */
    @Override
    public Iterator<Attribute> getAdditionalAttributes(
            HttpServletRequest request, HttpServletResponse response, StartElement event) {
        if (this.attributes == null) {
            return null;
        }

        final QName eventName = event.getName();
        final String localPart = eventName.getLocalPart();
        final Map<String, String> attributes = this.attributes.get(localPart);
        if (attributes == null || attributes.size() == 0) {
            return null;
        }

        final List<Attribute> newAttributes = new ArrayList<Attribute>(attributes.size());
        for (final Map.Entry<String, String> attributeEntry : attributes.entrySet()) {
            final String key = attributeEntry.getKey();
            final String value = attributeEntry.getValue();
            final Attribute attribute = xmlEventFactory.createAttribute(key, value);
            newAttributes.add(attribute);
        }

        return newAttributes.iterator();
    }

    /* (non-Javadoc)
     * @see org.apereo.portal.rendering.AttributeSource#getCacheKey(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
     */
    @Override
    public CacheKey getCacheKey(HttpServletRequest request, HttpServletResponse response) {
        return CacheKey.build("StaticAttributeSource");
    }
}