Let IntroductionResponse know if introduction can succeed

and use this information in the android UI for showing that the user
needs to wait or not.

briar-android/src/main/java/org/briarproject/briar/android/conversation/ConversationVisitor.java

@@ -252,12 +252,12 @@ class ConversationVisitor implements
 		if (r.isLocal()) {
 			String text;
 			if (r.wasAccepted()) {
+				String suffix = r.canSucceed() ? "\n\n" + ctx.getString(
+						R.string.introduction_response_accepted_sent_info,
+						introducedAuthor) : "";
 				text = ctx.getString(
 						R.string.introduction_response_accepted_sent,
-						introducedAuthor)
+						introducedAuthor) + suffix;
-						+ "\n\n" + ctx.getString(
-						R.string.introduction_response_accepted_sent_info,
-						introducedAuthor);
 			} else {
 				text = ctx.getString(
 						R.string.introduction_response_declined_sent,

briar-api/src/main/java/org/briarproject/briar/api/introduction/IntroductionResponse.java

@@ -20,16 +20,18 @@ public class IntroductionResponse extends ConversationResponse {
 	private final Author introducedAuthor;
 	private final AuthorInfo introducedAuthorInfo;
 	private final Role ourRole;
+	private final boolean canSucceed;
 
 	public IntroductionResponse(MessageId messageId, GroupId groupId, long time,
 			boolean local, boolean read, boolean sent, boolean seen,
 			SessionId sessionId, boolean accepted, Author author,
-			AuthorInfo introducedAuthorInfo, Role role) {
+			AuthorInfo introducedAuthorInfo, Role role, boolean canSucceed) {
 		super(messageId, groupId, time, local, read, sent, seen, sessionId,
 				accepted);
 		this.introducedAuthor = author;
 		this.introducedAuthorInfo = introducedAuthorInfo;
 		this.ourRole = role;
+		this.canSucceed = canSucceed;
 	}
 
 	public Author getIntroducedAuthor() {
@@ -40,6 +42,10 @@ public class IntroductionResponse extends ConversationResponse {
 		return introducedAuthorInfo;
 	}
 
+	public boolean canSucceed() {
+		return canSucceed;
+	}
+
 	public boolean isIntroducer() {
 		return ourRole == INTRODUCER;
 	}
@@ -48,4 +54,5 @@ public class IntroductionResponse extends ConversationResponse {
 	public <T> T accept(ConversationMessageVisitor<T> v) {
 		return v.visitIntroductionResponse(this);
 	}
+
 }

briar-core/src/main/java/org/briarproject/briar/introduction/AbstractProtocolEngine.java

@@ -146,8 +146,8 @@ abstract class AbstractProtocolEngine<S extends Session>
 	}
 
 	void broadcastIntroductionResponseReceivedEvent(Transaction txn, Session s,
-			AuthorId sender, Author otherAuthor, AbstractIntroductionMessage m)
+			AuthorId sender, Author otherAuthor, AbstractIntroductionMessage m,
-			throws DbException {
+			boolean canSucceed) throws DbException {
 		AuthorId localAuthorId = identityManager.getLocalAuthor(txn).getId();
 		Contact c = contactManager.getContact(txn, sender, localAuthorId);
 		AuthorInfo otherAuthorInfo =
@@ -156,7 +156,7 @@ abstract class AbstractProtocolEngine<S extends Session>
 				new IntroductionResponse(m.getMessageId(), m.getGroupId(),
 						m.getTimestamp(), false, false, false, false,
 						s.getSessionId(), m instanceof AcceptMessage,
-						otherAuthor, otherAuthorInfo, s.getRole());
+						otherAuthor, otherAuthorInfo, s.getRole(), canSucceed);
 		IntroductionResponseReceivedEvent e =
 				new IntroductionResponseReceivedEvent(response, c.getId());
 		txn.attach(e);

briar-core/src/main/java/org/briarproject/briar/introduction/IntroduceeProtocolEngine.java

@@ -363,7 +363,7 @@ class IntroduceeProtocolEngine
 
 		// Broadcast IntroductionResponseReceivedEvent
 		broadcastIntroductionResponseReceivedEvent(txn, s,
-				s.getIntroducer().getId(), s.getRemote().author, m);
+				s.getIntroducer().getId(), s.getRemote().author, m, false);
 
 		// Determine next state
 		IntroduceeState state =

briar-core/src/main/java/org/briarproject/briar/introduction/IntroducerProtocolEngine.java

@@ -294,7 +294,7 @@ class IntroducerProtocolEngine
 
 		// Broadcast IntroductionResponseReceivedEvent
 		broadcastIntroductionResponseReceivedEvent(txn, s, sender.getId(),
-				other, m);
+				other, m, true);
 
 		// Move to the next state
 		return new IntroducerSession(s.getSessionId(), state,
@@ -349,7 +349,7 @@ class IntroducerProtocolEngine
 
 		// Broadcast IntroductionResponseReceivedEvent
 		broadcastIntroductionResponseReceivedEvent(txn, s, sender.getId(),
-				other, m);
+				other, m, false);
 
 		return new IntroducerSession(s.getSessionId(), START,
 				s.getRequestTimestamp(), introduceeA, introduceeB);
@@ -403,7 +403,7 @@ class IntroducerProtocolEngine
 
 		// Broadcast IntroductionResponseReceivedEvent
 		broadcastIntroductionResponseReceivedEvent(txn, s, sender.getId(),
-				other, m);
+				other, m, false);
 
 		return new IntroducerSession(s.getSessionId(), state,
 				s.getRequestTimestamp(), introduceeA, introduceeB);
@@ -451,7 +451,7 @@ class IntroducerProtocolEngine
 
 		// Broadcast IntroductionResponseReceivedEvent
 		broadcastIntroductionResponseReceivedEvent(txn, s, sender.getId(),
-				other, m);
+				other, m, false);
 
 		return new IntroducerSession(s.getSessionId(), START,
 				s.getRequestTimestamp(), introduceeA, introduceeB);

briar-core/src/main/java/org/briarproject/briar/introduction/IntroductionManagerImpl.java

@@ -52,6 +52,9 @@ import javax.inject.Inject;
 
 import static org.briarproject.briar.api.introduction.Role.INTRODUCEE;
 import static org.briarproject.briar.api.introduction.Role.INTRODUCER;
+import static org.briarproject.briar.introduction.IntroduceeState.REMOTE_DECLINED;
+import static org.briarproject.briar.introduction.IntroducerState.A_DECLINED;
+import static org.briarproject.briar.introduction.IntroducerState.B_DECLINED;
 import static org.briarproject.briar.introduction.IntroducerState.START;
 import static org.briarproject.briar.introduction.IntroductionConstants.GROUP_KEY_CONTACT_ID;
 import static org.briarproject.briar.introduction.MessageType.ABORT;
@@ -466,6 +469,7 @@ class IntroductionManagerImpl extends ConversationClientImpl
 		Role role = sessionParser.getRole(bdfSession);
 		SessionId sessionId;
 		Author author;
+		boolean canSucceed;
 		if (role == INTRODUCER) {
 			IntroducerSession session =
 					sessionParser.parseIntroducerSession(bdfSession);
@@ -475,11 +479,15 @@ class IntroductionManagerImpl extends ConversationClientImpl
 			} else {
 				author = session.getIntroduceeA().author;
 			}
+			IntroducerState s = session.getState();
+			canSucceed = s != START && s != A_DECLINED && s != B_DECLINED;
 		} else if (role == INTRODUCEE) {
 			IntroduceeSession session = sessionParser
 					.parseIntroduceeSession(contactGroupId, bdfSession);
 			sessionId = session.getSessionId();
 			author = session.getRemote().author;
+			IntroduceeState s = session.getState();
+			canSucceed = s != IntroduceeState.START && s != REMOTE_DECLINED;
 		} else throw new AssertionError();
 		AuthorInfo authorInfo = authorInfos.get(author.getId());
 		if (authorInfo == null) {
@@ -488,7 +496,7 @@ class IntroductionManagerImpl extends ConversationClientImpl
 		}
 		return new IntroductionResponse(m, contactGroupId, meta.getTimestamp(),
 				meta.isLocal(), meta.isRead(), status.isSent(), status.isSeen(),
-				sessionId, accept, author, authorInfo, role);
+				sessionId, accept, author, authorInfo, role, canSucceed);
 	}
 
 	private void removeSessionWithIntroducer(Transaction txn,

briar-core/src/test/java/org/briarproject/briar/introduction/IntroductionIntegrationTest.java

@@ -185,6 +185,7 @@ public class IntroductionIntegrationTest
 		assertEquals(introducee2.getAuthor().getName(),
 				listener0.getResponse().getIntroducedAuthor().getName());
 		assertGroupCount(messageTracker0, g1.getId(), 2, 1);
+		assertTrue(listener0.getResponse().canSucceed());
 
 		// sync second ACCEPT message
 		sync2To0(1, true);
@@ -193,6 +194,7 @@ public class IntroductionIntegrationTest
 		assertEquals(introducee1.getAuthor().getName(),
 				listener0.getResponse().getIntroducedAuthor().getName());
 		assertGroupCount(messageTracker0, g2.getId(), 2, 1);
+		assertTrue(listener0.getResponse().canSucceed());
 
 		// sync forwarded ACCEPT messages to introducees
 		sync0To1(1, true);
@@ -290,6 +292,7 @@ public class IntroductionIntegrationTest
 		// assert that the name on the decline event is correct
 		assertEquals(introducee2.getAuthor().getName(),
 				listener0.getResponse().getIntroducedAuthor().getName());
+		assertFalse(listener0.getResponse().canSucceed());
 
 		// sync second response
 		sync2To0(1, true);
@@ -307,6 +310,7 @@ public class IntroductionIntegrationTest
 		eventWaiter.await(TIMEOUT, 1);
 		assertEquals(introducee1.getAuthor().getName(),
 				listener2.getResponse().getIntroducedAuthor().getName());
+		assertFalse(listener2.getResponse().canSucceed());
 
 		// note how the introducer does not forward the second response,
 		// because after the first decline the protocol finished
@@ -381,6 +385,7 @@ public class IntroductionIntegrationTest
 		eventWaiter.await(TIMEOUT, 1);
 		assertEquals(contact2From0.getAuthor().getName(),
 				listener1.getResponse().getIntroducedAuthor().getName());
+		assertFalse(listener1.getResponse().canSucceed());
 
 		assertFalse(contactManager1
 				.contactExists(author2.getId(), author1.getId()));