package org.wyona.cms.cocoon.acting;

import org.apache.avalon.framework.configuration.Configurable;
import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.configuration.ConfigurationException;
import org.apache.avalon.framework.parameters.Parameters;
import org.apache.avalon.framework.thread.ThreadSafe;
import org.apache.cocoon.Constants;
import org.apache.cocoon.acting.AbstractComplementaryConfigurableAction;
import org.apache.cocoon.acting.ValidatorActionHelper;
import org.apache.cocoon.environment.Redirector;
import org.apache.cocoon.environment.Request;
import org.apache.cocoon.environment.Session;
import org.apache.cocoon.environment.SourceResolver;
import org.apache.cocoon.util.Tokenizer;
import org.apache.xpath.XPathAPI;

import java.net.URL;
import java.util.HashMap;
import java.util.Map;
import java.util.StringTokenizer;

import org.w3c.dom.Document;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;

import org.wyona.cms.ac.Identity;
import org.wyona.cms.ac.Policy;

/**
 * @author Michael Wechner
 * @created 1.11.18
 * @version 2.1.6
 */
public class PMLAuthorizerAction extends AbstractAuthorizerAction{
  private String authenticator_id=null;
  private String domain=null;
  private String port=null;
  private String context=null;
  private String policies=null;
/**
 *
 */
 public void configure(Configuration conf) throws ConfigurationException{
   super.configure(conf);

   Configuration authenticatorConf=conf.getChild("authenticator");
   authenticator_id=authenticatorConf.getAttribute("id");
   getLogger().debug("CONFIGURATION: authenticator id="+authenticator_id);
/*
   if(authenticator_id == null){
     throw new ConfigurationException("No authenticator id set");
     }
*/

   Configuration domainConf=conf.getChild("domain");
   domain=domainConf.getValue("127.0.0.1");
   getLogger().debug("CONFIGURATION: domain="+domain);

   Configuration portConf=conf.getChild("port");
   port=portConf.getValue(null);
   getLogger().debug("CONFIGURATION: port="+port);

   Configuration contextConf=conf.getChild("context");
   context=contextConf.getValue(null);
   getLogger().debug("CONFIGURATION: context="+context);

   Configuration policiesConf=conf.getChild("policies");
   policies=policiesConf.getValue(null);
   getLogger().debug("CONFIGURATION: policies="+policies);   
   }
/**
 *
 */
  public boolean authorize(Request request,Map map) throws Exception{
    String remoteAddress=request.getRemoteAddr();

    // Permit Identity and Policy requests for localhost
    if(remoteAddress.equals("127.0.0.1")){
    //if(remoteAddress.equals("127.0.0.1") && (.indexOf(policies)==0)){
      return true;
      }
    
    // Get policy
    Document policyDoc=null;
    try{
      policyDoc=getPolicyDoc(request);
      }
    catch(Exception e){
      getLogger().error(".authorize(): "+e);
      return false;
      }
    Policy policy=new Policy(policyDoc,getLogger());

    // Read action (read, write, publish, etc.)
    String action=XPathAPI.selectSingleNode(policyDoc,"/ac/request/action/@name").getNodeValue(); //"read";
    getLogger().debug("action: "+action);

    // Check permissions
    if(policy.authorizeWorld(action)){
      return true;
      }

    if(policy.authorizeMachine(action,remoteAddress)){
      return true;
      }

    Session session=request.getSession(true);
    if(session == null){
      getLogger().error("No session object");
      return false;
      }

    // If there are more than one authenticator enabled, then check corresponding id
    String authenticator_id=(String)session.getAttribute("org.wyona.cms.cocoon.acting.IMLAuthenticator.id");
    if(this.authenticator_id != authenticator_id){
      getLogger().error("Bad authenticator: "+authenticator_id+" (Authorizer's authenticator: "+this.authenticator_id+")");
      return false;
      }

    Identity identity=(Identity)session.getAttribute("org.wyona.cms.ac.Identity");
    if(identity != null){
      if(policy.authorizeUser(action,identity.getUsername())){
        return true;
        }

      String[] groupname=identity.getGroupnames();
      for(int i=0;i<groupname.length;i++){
        if(policy.authorizeGroup(action,groupname[i])){
          return true;
          }
        }
      }

    getLogger().error("Permission denied");
    return false;
    }
/**
 *
 */
  private Document getPolicyDoc(Request request) throws Exception{
    String context=request.getContextPath();
    int port=request.getServerPort();
    String sitemap_uri=request.getSitemapURI();
    String pmlURLString="http://"+domain;
    if(this.port != null){
      pmlURLString=pmlURLString+":"+this.port;
      }
    else{
      pmlURLString=pmlURLString+":"+port;
      }
    if(this.context != null){
      pmlURLString=pmlURLString+this.context;
      }
    else{
      pmlURLString=pmlURLString+context;
      }
    pmlURLString=pmlURLString+"/"+policies+sitemap_uri+".acml";
    //pmlURLString=pmlURLString+"/"+policies+sitemap_uri+".pml";
    getLogger().error(".getPolicyDoc(): "+pmlURLString);
    DocumentBuilderFactory dbf=DocumentBuilderFactory.newInstance();
    DocumentBuilder db=dbf.newDocumentBuilder();
    return db.parse(new URL(pmlURLString).openStream());
    }
/**
 *
 */
/*
  private void parse() throws Exception{
    javax.xml.parsers.SAXParserFactory spf=javax.xml.parsers.SAXParserFactory.newInstance();
    javax.xml.parsers.SAXParser sp=spf.newSAXParser();
    }
*/
  }