/**
 * 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.portlet.container.services;

import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import org.apache.pluto.container.PortletWindow;
import org.apache.pluto.container.om.portlet.PortletApplicationDefinition;
import org.apache.pluto.container.om.portlet.UserAttribute;
import org.apereo.portal.portlet.om.IPortletDefinition;
import org.apereo.portal.portlet.om.IPortletEntity;
import org.apereo.portal.portlet.om.IPortletWindow;
import org.apereo.portal.portlet.registry.IPortletDefinitionRegistry;
import org.apereo.portal.portlet.registry.IPortletWindowRegistry;
import org.apereo.portal.portlet.rendering.IPortletRenderer;
import org.jasig.services.persondir.IPersonAttributeDao;
import org.jasig.services.persondir.IPersonAttributes;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

/**
 * Default implementation of {@link RequestAttributeService} that can construct the multi-valued
 * user attribute map that corresponds to the attribute with the name {@link
 * IPortletRenderer#MULTIVALUED_USERINFO_MAP_ATTRIBUTE}.
 *
 */
@Service
public class RequestAttributeServiceImpl implements RequestAttributeService {

    private IPersonAttributeDao personAttributeDao;
    private IPortletWindowRegistry portletWindowRegistry;
    private IPortletDefinitionRegistry portletDefinitionRegistry;

    @Autowired
    public void setPersonAttributeDao(IPersonAttributeDao personAttributeDao) {
        this.personAttributeDao = personAttributeDao;
    }

    @Autowired
    public void setPortletWindowRegistry(IPortletWindowRegistry portletWindowRegistry) {
        this.portletWindowRegistry = portletWindowRegistry;
    }

    @Autowired
    public void setPortletDefinitionRegistry(IPortletDefinitionRegistry portletDefinitionRegistry) {
        this.portletDefinitionRegistry = portletDefinitionRegistry;
    }

    /*
     * (non-Javadoc)
     * @see org.apereo.portal.portlet.container.services.RequestAttributeService#getAttribute(javax.portlet.PortletRequest, org.apache.pluto.container.PortletWindow, java.lang.String)
     */
    @Override
    public Object getAttribute(
            HttpServletRequest httpServletRequest,
            PortletWindow plutoPortletWindow,
            String attributeName) {
        if (IPortletRenderer.MULTIVALUED_USERINFO_MAP_ATTRIBUTE.equals(attributeName)) {

            //Get the list of user attributes the portal knows about the user
            final String remoteUser = httpServletRequest.getRemoteUser();
            if (remoteUser == null) {
                return null;
            }

            final IPortletWindow portletWindow =
                    this.portletWindowRegistry.convertPortletWindow(
                            httpServletRequest, plutoPortletWindow);
            final List<? extends UserAttribute> expectedUserAttributes =
                    this.getExpectedUserAttributes(httpServletRequest, portletWindow);

            return getMultiValuedUserInfoMap(remoteUser, expectedUserAttributes);
        }

        return null;
    }

    /**
     * @param remoteUser
     * @param expectedUserAttributes
     * @return an unmodifiable map containing the multi-valued attributes for the user within the
     *     list of expected attributes
     */
    protected Map<String, List<Object>> getMultiValuedUserInfoMap(
            String remoteUser, List<? extends UserAttribute> expectedUserAttributes) {
        final IPersonAttributes personAttributes = this.personAttributeDao.getPerson(remoteUser);
        if (personAttributes == null) {
            return Collections.emptyMap();
        }

        final Map<String, List<Object>> resultUserInfoMap =
                new HashMap<String, List<Object>>(expectedUserAttributes.size());

        //Copy expected attributes to the USER_INFO Map
        final Map<String, List<Object>> attributes = personAttributes.getAttributes();
        for (final UserAttribute userAttributeDD : expectedUserAttributes) {
            final String userAttributeName = userAttributeDD.getName();

            //containsKey check to handle attributes with a single null value
            if (attributes.containsKey(userAttributeName)) {
                final List<Object> list_valueObjs = attributes.get(userAttributeName);
                resultUserInfoMap.put(userAttributeName, list_valueObjs);
            }
        }

        return Collections.unmodifiableMap(resultUserInfoMap);
    }
    /**
     * Get the list of user attributes the portlet expects.
     *
     * @param request The current request.
     * @param portletWindow The window to get the expected user attributes for.
     * @return The List of expected user attributes for the portlet
     */
    protected List<? extends UserAttribute> getExpectedUserAttributes(
            HttpServletRequest request, final IPortletWindow portletWindow) {
        final IPortletEntity portletEntity = portletWindow.getPortletEntity();
        final IPortletDefinition portletDefinition = portletEntity.getPortletDefinition();
        final PortletApplicationDefinition portletApplicationDescriptor =
                this.portletDefinitionRegistry.getParentPortletApplicationDescriptor(
                        portletDefinition.getPortletDefinitionId());

        return portletApplicationDescriptor.getUserAttributes();
    }
}