package com.nailabs.abac.credential;

import com.nailabs.abac.test.RtmlTest;

import edu.stanford.rt.credential.CredentialDomain;
import edu.stanford.rt.credential.CredentialStore;
import edu.stanford.rt.credential.HashID;
import edu.stanford.rt.credential.RTContext;

import edu.stanford.rt.parser.*;
import edu.stanford.peer.rbtm.credential.*;
import edu.stanford.peer.rbtm.util.ResultEvidenceMap;

import java.io.*;
import java.net.*;
import java.util.*;

/**
 * A distributed discovery engine based on the RTML-aware GraphEngine. 
 */
public class DDEngine extends RtmlEngine {

    protected RTParser parser;

    protected RTContext context;

    protected Properties lookupMap = new Properties();

    static String PORT_PROPERTY = "com.nailabs.abac.discovery.port";

    /**
     * The default constructor grabs parameters from the configuration 
     * HashMap, including [Parser] and [PrepInfo] sections. 
     */
    public DDEngine(HashMap config) {
	super();
	parser = (RTParser)config.get("DDEParser");
	context = (RTContext)config.get("DDEContext");
	lookupMap = (Properties)config.get("PrepInfo");
	store = (CredentialStore)config.get("DDEStore");
	try {
	    if(context == null) {
			  context = new RTContext(parser);
	    }
	    if(store == null) {
			  store = (CredentialStore)config.get("CredentialStore");
	    }
	    if(store == null) {	    
			  store = new CredentialStore(parser);
	    }
	} catch (Exception ex) {
	    ex.printStackTrace();
	}
    }

    protected URL createURL(String host, String operation, String expression) {
	StringBuffer buff = new StringBuffer("http://");
	buff.append(host).append("?");
	buff.append(operation).append("=").append(expression);
	try {
	    System.out.println("Constructing url = " + buff);
	    return new URL(buff.toString());
	}
	catch(Exception ex) {
	    ex.printStackTrace();
	}
	return null;
    }


    protected Vector parseOutput(URL url) {
	Vector documents = new Vector();
	StringWriter out = null;

	try {
	    URLConnection connection = url.openConnection();
	    InputStream in = connection.getInputStream();
	    BufferedReader buffedReader
		= new BufferedReader(new InputStreamReader(in));
	    out = new StringWriter();
	    // grab the first line so we don't have an empty vector item
	    out.write(buffedReader.readLine());
	    while(true) {
		String line = buffedReader.readLine();
		if(line == null)break;
		if(line.startsWith("<?xml")) {
		    documents.add(out.getBuffer().toString());
		    out = new StringWriter();
		}
		out.write(line);
		out.write("\n");
	    }
	    
	} catch(Exception ex) {
	    //ex.printStackTrace();
	}
	if(out != null) {
	    documents.add(out.getBuffer().toString());
	}
	for(int cnt = 0; cnt < documents.size(); cnt++) {
	    try {
		String xml = (String)documents.get(cnt);
		if(xml.equals("null")) {
		    documents.remove(cnt--);
		    continue;
		}
		System.out.println("---------begin xml-------");
		System.out.println(xml);
		System.out.println("----------end xml--------");
		InputStream in = new ByteArrayInputStream(xml.getBytes());
		documents.set
		    (cnt, (Object) parser.parseCredentialDomain(in,context));
	    } catch(Exception ex) {
		ex.printStackTrace();
		documents.remove(cnt--);
	    }
	}
	return documents;
    }

    protected String getLocation(EntityExpression expr) {
	String base;
	
        if(expr instanceof Entity) {
	    base = expr.toString();
	} else if(expr instanceof edu.stanford.peer.rbtm.credential.Role) {
	    base = 
	  ((edu.stanford.peer.rbtm.credential.Role)expr).getBase().toString();
	} else if(expr instanceof edu.stanford.peer.rbtm.credential.LinkedRole)
	    {
	    base = ((edu.stanford.peer.rbtm.credential.LinkedRole)expr).getFirstRole().getBase().toString();
	} else if(expr instanceof Intersection) {
	    base = getLocation((EntityExpression)
			       ((Intersection)expr).getParts().next());
	} else {
	    base = new String();
	}
	System.out.println("getting url for " + base);
	return lookupMap.getProperty(base);
    }

    protected Vector discover(String operation, EntityExpression expr) {
	URL url = createURL(getLocation(expr), operation, 
		      RtmlExpression.toString(expr));
	Vector v = parseOutput(url);
	Vector results = new Vector(v.size());
	Iterator domains = v.iterator();
	while(domains.hasNext()) {
	    CredentialDomain domain = (CredentialDomain)domains.next();
	    HashID hash = domain.getHashID();
	    try {
		addDomain(domain);	
		Iterator creds = RtmlEngine.convert(domain).iterator();
		while(creds.hasNext()) {
		    RtmlCredential cred = (RtmlCredential)creds.next();
		    results.add(cred);
		    System.out.println("-----+Adding " + cred);
		}
	    } catch(Exception ex) {
		System.err.println("Error with credential domain " +
				   domain.getHashID());
		ex.printStackTrace();
	    }
	}
	return results;
    }

    synchronized public Iterator 
    findCredentialsDefiningRole(edu.stanford.peer.rbtm.credential.Role r) {
	return discover("Defines", r).iterator();
    }

    synchronized public Collection getCredentialsIssuedBy(Entity e) {
	return discover("Issuer", e);
    }

    synchronized public Iterator findCredentialsBySubject(EntityExpression s) {
	return discover("Subject", s).iterator();
    }

    public static void main(String[] args) {
	if(System.getProperty("edu.stanford.rt.SystemDomain") == null) {
	    System.setProperty("edu.stanford.rt.SystemDomain",
			       "../rtml/schemas/SystemSpec.xml");
	}
	HashMap conf = new HashMap(6);
	Properties prepInfo = new Properties();
	prepInfo.setProperty("SE", 
								"wwinsbor1.rv.nailabs.com:8180/demo/se-discovery");
	prepInfo.setProperty("SAdmir!FakeHashKeySAdmir", 
								"wwinsbor1.rv.nailabs.com:8180/demo/se-discovery");
	prepInfo.setProperty("US", 
								"wwinsbor1.rv.nailabs.com:8180/demo/us-discovery");
	prepInfo.setProperty("USEUCOM", 
								"wwinsbor1.rv.nailabs.com:8180/demo/us-discovery");
	prepInfo.setProperty("USSH!FakeHashKeyUSSH", 
								"wwinsbor1.rv.nailabs.com:8180/demo/us-discovery");
	prepInfo.setProperty("USN", 
								"wwinsbor1.rv.nailabs.com:8180/demo/us-discovery");
	prepInfo.setProperty("RADMSmith", 
								"wwinsbor1.rv.nailabs.com:8180/demo/us-discovery");
	conf.put("PrepInfo", prepInfo);
	Properties rtml = new Properties(System.getProperties());
	if(rtml.getProperty("DDEStore") == null) {
	    rtml.setProperty("DDEStore", "test/rtml/dde-client.xml");
	}
	conf.put("RTML", rtml);
	RtmlTest.parseDiscoveryStore(conf);
	try {
	    DDEngine engine = new DDEngine(conf);
	    ResultEvidenceMap map = (ResultEvidenceMap)
			  engine.backwardSearch(new Role("SAdmir!FakeHashKeySAdmir",
														"getsSLocs"));
	    Collection v = map.resultSet();
	    for(Iterator i = v.iterator(); i.hasNext(); ) {
			  System.out.println("--------------------");
			  Object result = i.next();
			  System.out.println(result.toString());
			  System.out.println(map.getResultEvidence(result).toString());
	    }
		 System.out.println("--------------------");
		 map = (ResultEvidenceMap)
			  engine.forwardSearch(new SimpleEntity("USSH!FakeHashKeyUSSH"));
		 //engine.forwardSearch(new SimpleEntity("SAdmir!FakeHashKeySAdmir"));
		 //engine.forwardSearch(new Role("US!FakeHashKeyUS","usr"));

	    v = map.resultSet();
	    for(Iterator i = v.iterator(); i.hasNext(); ) {
			  System.out.println("--------------------");
			  Object result = i.next();
			  System.out.println(result.toString());
			  System.out.println(map.getResultEvidence(result).toString());
	    }
	} catch(Exception ex) {
	    ex.printStackTrace();
	}
    }
}