package backtype.storm.security.auth;

import java.util.Map;
import java.util.Set;
import java.util.concurrent.atomic.AtomicInteger;
import java.net.InetAddress;
import com.google.common.annotations.VisibleForTesting;
import java.security.AccessControlContext;
import java.security.AccessController;
import java.security.Principal;
import javax.security.auth.Subject;

/**
 * context request context includes info about (1) remote address, (2) remote
 * subject and primary principal (3) request ID
 */
public class ReqContext {
	private static final AtomicInteger uniqueId = new AtomicInteger(0);
	private Subject _subject;
	private InetAddress _remoteAddr;
	private Integer _reqID;
	private Map _storm_conf;

	/**
	 * Get a request context associated with current thread
	 * 
	 * @return
	 */
	public static ReqContext context() {
		return ctxt.get();
	}

	// each thread will have its own request context
	private static final ThreadLocal<ReqContext> ctxt = new ThreadLocal<ReqContext>() {
		@Override
		protected ReqContext initialValue() {
			return new ReqContext(AccessController.getContext());
		}
	};

	// private constructor
	@VisibleForTesting
	ReqContext(AccessControlContext acl_ctxt) {
		_subject = Subject.getSubject(acl_ctxt);
		_reqID = uniqueId.incrementAndGet();
	}

	/**
	 * client address
	 */
	public void setRemoteAddress(InetAddress addr) {
		_remoteAddr = addr;
	}

	public InetAddress remoteAddress() {
		return _remoteAddr;
	}

	/**
	 * Set remote subject explicitly
	 */
	public void setSubject(Subject subject) {
		_subject = subject;
	}

	/**
	 * Retrieve client subject associated with this request context
	 */
	public Subject subject() {
		return _subject;
	}

	/**
	 * The primary principal associated current subject
	 */
	public Principal principal() {
		if (_subject == null)
			return null;
		Set<Principal> princs = _subject.getPrincipals();
		if (princs.size() == 0)
			return null;
		return (Principal) (princs.toArray()[0]);
	}

	/**
	 * request ID of this request
	 */
	public Integer requestID() {
		return _reqID;
	}
}