package org.esupportail.portal.channels.portlet;

import java.util.Enumeration;
import java.util.Map;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.jasig.portal.ChannelStaticData;
import org.jasig.portal.channels.portlet.CPortletAdapter;
import org.jasig.portal.container.om.portlet.UserAttributeListImpl;
import org.jasig.portal.security.IPerson;
import org.jasig.portal.security.ISecurityContext;
import org.jasig.portal.security.provider.cas.CasProxyTicketAcquisitionException;
import org.jasig.portal.security.provider.cas.CasSecurityContext;
import org.jasig.portal.security.provider.cas.ICasSecurityContext;
import org.springframework.util.StringUtils;

/**
 * A JSR 168 Portlet adapter that passes a CAS proxy ticket 
 * to portlets.
 */
public class CCasProxyPortletAdapter extends CPortletAdapter {

	/**
	 * A logger for the class.
	 */
	protected final Log log = LogFactory.getLog(getClass());

	/**
	 * The portlet parameter that contains the name of the 
	 * preferences attribute used to pass the PT to portlets.
	 */
	public static final String CAS_PROXY_TICKET_PREF_PARAM = "casProxyTicketPref";

	/**
	 * The default name of the preferences attribute used to pass the 
	 * PT to the portlet.
	 */
	public static final String DEFAULT_CAS_PROXY_TICKET_PREF = "casProxyTicket";

	/**
	 * The portlet parameter that contains the target service 
	 * of the PTs that will be passed to the portlet.
	 */
	public static final String CAS_TARGET_SERVICE_PARAM = "casTargetService";

	/**
	 * Bean constructor.
	 */
	public CCasProxyPortletAdapter() {
		super();
	}

	/**
	 * @return the name of the preferences attribute used to pass a PT to the portlet.
	 */
	protected String getCasProxyTicketPref(ChannelStaticData staticData) {
		String pref = (String) staticData.get(CAS_PROXY_TICKET_PREF_PARAM);
		if (!StringUtils.hasText(pref)) {
			pref = DEFAULT_CAS_PROXY_TICKET_PREF;
		}
		return pref;
	}
    
	/**
	 * @return the CAS target service of the portlet.
	 */
	protected String getCasTargetService(ChannelStaticData staticData) {
		return (String) staticData.get(CAS_TARGET_SERVICE_PARAM);
	}
    
	/**
	 * Looks for a security context
	 * @param rootContext the principal security context
	 * @return the CAS security contex, or null if not found.
	 */
	@SuppressWarnings("unchecked")
	private static ISecurityContext getCasContext(ISecurityContext context) {
		if (context instanceof CasSecurityContext) {
			return context;
		}
		Enumeration contextEnum = context.getSubContexts();
		while (contextEnum.hasMoreElements()) {
			ISecurityContext subContext = (ISecurityContext) contextEnum.nextElement();
			if (subContext instanceof ICasSecurityContext) {
				return subContext;
			}
		}
		return null;
	}

	/**
	 * @see org.jasig.portal.channels.portlet.CPortletAdapter#getUserInfo(
	 * java.lang.String, org.jasig.portal.ChannelStaticData, org.jasig.portal.container.om.portlet.UserAttributeListImpl)
	 */
	@SuppressWarnings("unchecked")
	@Override
	protected Map getUserInfo(String uid, ChannelStaticData staticData, UserAttributeListImpl userAttributes) {
		Map userInfo = super.getUserInfo(uid, staticData, userAttributes);
		String targetService = getCasTargetService(staticData);
		if (targetService == null) {
			log.debug("parameter [" + CAS_TARGET_SERVICE_PARAM + "] is null, no proxy ticket passed to the portlet");
			return userInfo;
		}
		IPerson person = staticData.getPerson();
        if (person == null) {
			log.error("no person, no proxy ticket passed to the portlet");
			return userInfo;
        }
		
		ISecurityContext context = person.getSecurityContext();
        if (context == null) {
			log.error("no security context, no proxy ticket passed to the portlet");
			return userInfo;
        }
        ISecurityContext casContext = getCasContext(context);
        if (casContext == null) {
			log.debug("no CAS security context, no proxy ticket passed to the portlet");
			return userInfo;
        }
        if (!casContext.isAuthenticated()) {
			log.debug("no CAS authentication, no proxy ticket passed to the portlet");
			return userInfo;
        }
        try {
			String proxyTicket = ((ICasSecurityContext) casContext).getCasServiceToken(targetService);
			userInfo.put(getCasProxyTicketPref(staticData), proxyTicket);
		} catch (CasProxyTicketAcquisitionException e) {
			log.error("no proxy ticket passed to the portlet: " + e);
		}
		return userInfo;
	}
    
}