/**
 * 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.delegation;

import java.io.Writer;
import java.util.Map;
import javax.portlet.PortletRequest;
import javax.portlet.PortletResponse;
import javax.portlet.RenderRequest;
import javax.portlet.RenderResponse;
import javax.portlet.ResourceRequest;
import javax.portlet.ResourceResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.pluto.tags.Constants;
import org.apereo.portal.api.portlet.DelegationRequest;
import org.apereo.portal.api.portlet.DelegationResponse;
import org.apereo.portal.api.portlet.PortletDelegationDispatcher;
import org.apereo.portal.api.portlet.PortletDelegationLocator;
import org.apereo.portal.portlet.om.IPortletWindowId;
import org.apereo.portal.portlet.rendering.PortletOutputHandler;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.servlet.View;

/**
 */
public class PortletDelegationView implements View {
    /**
     * Model attribute to store the optional {@link Writer} to use when delegating a {@link
     * RenderRequest}
     */
    public static final String DELEGATE_RENDER_OUTPUT_HANDLER = "DELEGATE_RENDER_OUTPUT_HANDLER";

    /** Model attribute to store the optional {@link DelegationRequest} */
    public static final String DELEGATE_REQUEST = "DELEGATE_REQUEST";

    /** Model attribute to store the required {@link IPortletWindowId} */
    public static final String DELEGATE_PORTLET_WINDOW_ID = "DELEGATE_PORTLET_WINDOW_ID";

    protected final Logger logger = LoggerFactory.getLogger(getClass());

    private PortletDelegationLocator portletDelegationLocator;

    @Autowired
    public void setPortletDelegationLocator(PortletDelegationLocator portletDelegationLocator) {
        this.portletDelegationLocator = portletDelegationLocator;
    }

    /* (non-Javadoc)
     * @see org.springframework.web.servlet.View#getContentType()
     */
    @Override
    public String getContentType() {
        return null;
    }

    /* (non-Javadoc)
     * @see org.springframework.web.servlet.View#render(java.util.Map, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
     */
    @Override
    public void render(
            Map<String, ?> model, HttpServletRequest request, HttpServletResponse response)
            throws Exception {
        final IPortletWindowId portletWindowId =
                (IPortletWindowId) model.get(DELEGATE_PORTLET_WINDOW_ID);
        final DelegationRequest delegationRequest = (DelegationRequest) model.get(DELEGATE_REQUEST);

        final PortletRequest portletRequest =
                (PortletRequest) request.getAttribute(Constants.PORTLET_REQUEST);
        final PortletResponse portletResponse =
                (PortletResponse) request.getAttribute(Constants.PORTLET_RESPONSE);

        final PortletDelegationDispatcher requestDispatcher =
                portletDelegationLocator.getRequestDispatcher(portletRequest, portletWindowId);
        if (requestDispatcher == null) {
            throw new IllegalArgumentException(
                    "No PortletDelegationDispatcher exists for portlet window id: "
                            + portletWindowId);
        }
        this.logger.debug(
                "Found delegation dispatcher for portlet window id {} - {}",
                portletWindowId,
                requestDispatcher);

        final DelegationResponse delegationResponse;
        final String phase = (String) request.getAttribute(PortletRequest.LIFECYCLE_PHASE);
        if (PortletRequest.RENDER_PHASE.equals(phase)) {
            final PortletOutputHandler portletOutputHandler =
                    (PortletOutputHandler) model.get(DELEGATE_RENDER_OUTPUT_HANDLER);
            if (portletOutputHandler != null) {
                this.logger.debug(
                        "Delegating RenderRequest with custom Writer and {}", delegationRequest);
                delegationResponse =
                        requestDispatcher.doRender(
                                (RenderRequest) portletRequest,
                                (RenderResponse) portletResponse,
                                delegationRequest,
                                portletOutputHandler);
            } else {
                this.logger.debug(
                        "Delegating RenderRequest with default Writer and {}", delegationRequest);
                delegationResponse =
                        requestDispatcher.doRender(
                                (RenderRequest) portletRequest,
                                (RenderResponse) portletResponse,
                                delegationRequest);
            }
        } else if (PortletRequest.RESOURCE_PHASE.equals(phase)) {
            this.logger.debug("Delegating ResourceRequest and {}", delegationRequest);
            delegationResponse =
                    requestDispatcher.doServeResource(
                            (ResourceRequest) portletRequest,
                            (ResourceResponse) portletResponse,
                            delegationRequest);
        } else {
            throw new UnsupportedOperationException(
                    "Portlet lifecycle phase "
                            + phase
                            + " is not supported by the delegation view");
        }

        this.logger.debug("{}", delegationResponse);
    }
}