3 files changed, 310 insertions, 51 deletions
diff --git a/Swiften/Disco/FeatureOracle.cpp b/Swiften/Disco/FeatureOracle.cpp
index 8328984..2baf87c 100644
--- a/Swiften/Disco/FeatureOracle.cpp
+++ b/Swiften/Disco/FeatureOracle.cpp
@@ -8,10 +8,12 @@
 
 #include <algorithm>
 #include <iterator>
+#include <unordered_set>
 #include <vector>
 
-#include <Swiften/Base/foreach.h>
+#include <Swiften/Base/Log.h>
 #include <Swiften/Disco/EntityCapsProvider.h>
+#include <Swiften/Elements/Idle.h>
 #include <Swiften/Elements/Presence.h>
 #include <Swiften/FileTransfer/FileTransferManager.h>
 #include <Swiften/JID/JID.h>
@@ -20,78 +22,178 @@
 namespace Swift {
 
 FeatureOracle::FeatureOracle(EntityCapsProvider* capsProvider, PresenceOracle* presenceOracle) : capsProvider_(capsProvider), presenceOracle_(presenceOracle) {
-
 }
 
 Tristate FeatureOracle::isFileTransferSupported(const JID& jid) {
-    DiscoInfo::ref discoInfo = getDiscoResultForJID(jid);
-    if (discoInfo) {
-        return FileTransferManager::isSupportedBy(discoInfo) ? Yes : No;
+    Tristate fileTransferSupported = No;
+
+    auto isYesOrMaybe = [](Tristate tristate) { return tristate == Yes || tristate == Maybe; };
+    auto isYes = [](Tristate tristate) { return tristate == Yes; };
+
+    auto supportedFeatures = getFeaturesForJID(jid);
+
+    auto jingleSupported = isFeatureSupported(supportedFeatures, DiscoInfo::JingleFeature);
+    auto jingleFTSupported = isFeatureSupported(supportedFeatures, DiscoInfo::JingleFTFeature);
+    auto jingleTransportIBBSupported = isFeatureSupported(supportedFeatures, DiscoInfo::JingleTransportsIBBFeature);
+    auto jingleTransportS5BSupported = isFeatureSupported(supportedFeatures, DiscoInfo::JingleTransportsS5BFeature);
+
+    if (isYes(jingleSupported) && isYes(jingleFTSupported) && (isYes(jingleTransportIBBSupported) || isYes(jingleTransportS5BSupported))) {
+        fileTransferSupported = Yes;
     }
-    else {
-        return Maybe;
+    else if (isYesOrMaybe(jingleSupported) && isYesOrMaybe(jingleFTSupported) && (isYesOrMaybe(jingleTransportIBBSupported) || isYesOrMaybe(jingleTransportS5BSupported))) {
+        fileTransferSupported = Maybe;
     }
+
+    return fileTransferSupported;
 }
 
 Tristate FeatureOracle::isMessageReceiptsSupported(const JID& jid) {
-    return isFeatureSupported(jid, DiscoInfo::MessageDeliveryReceiptsFeature);
+    return isFeatureSupported(getFeaturesForJID(jid), DiscoInfo::MessageDeliveryReceiptsFeature);
 }
 
 Tristate FeatureOracle::isMessageCorrectionSupported(const JID& jid) {
-    return isFeatureSupported(jid, DiscoInfo::MessageCorrectionFeature);
+    return isFeatureSupported(getFeaturesForJID(jid), DiscoInfo::MessageCorrectionFeature);
+}
+
+Tristate FeatureOracle::isWhiteboardSupported(const JID& jid) {
+    return isFeatureSupported(getFeaturesForJID(jid), DiscoInfo::WhiteboardFeature);
 }
 
-DiscoInfo::ref FeatureOracle::getDiscoResultForJID(const JID& jid) {
-    DiscoInfo::ref discoInfo;
+class PresenceFeatureAvailablityComparator {
+    public:
+        static int preferenceFromStatusShow(StatusShow::Type showType) {
+            switch (showType) {
+                case StatusShow::FFC:
+                    return 5;
+                case StatusShow::Online:
+                    return 4;
+                case StatusShow::DND:
+                    return 3;
+                case StatusShow::Away:
+                    return 2;
+                case StatusShow::XA:
+                    return 1;
+                case StatusShow::None:
+                    return 0;
+            }
+            assert(false);
+            return -1;
+        }
+
+        static int compareWithoutResource(const Presence::ref& a, const Presence::ref& b) {
+            int aPreference = preferenceFromStatusShow(a->getShow());
+            int bPreference = preferenceFromStatusShow(b->getShow());
+
+            if (aPreference != bPreference) {
+                return aPreference < bPreference ? 1 : -1;
+            }
+
+            Idle::ref aIdle = a->getPayload<Idle>();
+            Idle::ref bIdle = b->getPayload<Idle>();
+
+            if (aIdle && !bIdle) {
+                return -1;
+            }
+            else if (!aIdle && bIdle) {
+                return 1;
+            }
+
+            if (a->getPriority() != b->getPriority()) {
+                return a->getPriority() < b->getPriority() ? 1 : -1;
+            }
+
+            return 0;
+        }
+
+        /*
+         * This method returns true, if \ref Presence \p b is more available than
+         * \ref Presence \p a.
+         * Going by \ref StatusShow::Type first, then by idle state, then by
+         * presence priority and finally by resource name.
+         */
+        bool operator()(const Presence::ref& a, const Presence::ref& b) {
+            int aMoreAvailableThanB = compareWithoutResource(a, b);
+            if (aMoreAvailableThanB < 0) {
+                return true;
+            }
+            else if (aMoreAvailableThanB > 0) {
+                return false;
+            }
+
+            return a->getFrom().getResource() < b->getFrom().getResource();
+        }
+};
+
+JID FeatureOracle::getMostAvailableClientForFileTrasfer(const JID& bareJID) {
+    JID fullJID;
+    assert(bareJID.isBare());
+
+    std::vector<Presence::ref> allPresences =  presenceOracle_->getAllPresence(bareJID);
+    std::sort(allPresences.begin(), allPresences.end(), PresenceFeatureAvailablityComparator());
+
+    for (const auto& presence : allPresences) {
+        if (presence->isAvailable()) {
+            if (isFileTransferSupported(presence->getFrom()) == Yes) {
+                fullJID = presence->getFrom();
+                break;
+            }
+        }
+    }
+
+    SWIFT_LOG_ASSERT(!fullJID.isBare(), error);
+    return fullJID;
+}
+
+std::unordered_map<std::string, Tristate> FeatureOracle::getFeaturesForJID(const JID& jid) {
+    std::unordered_map<std::string, Tristate> supportedFeatures;
     if (jid.isBare()) {
-        // Calculate the common subset of disco features of all available results and return that.
-        std::vector<Presence::ref> availablePresences =  presenceOracle_->getAllPresence(jid);
-
-        bool commonFeaturesInitialized = false;
-        std::vector<std::string> commonFeatures;
-        foreach(Presence::ref presence, availablePresences) {
-            DiscoInfo::ref presenceDiscoInfo = capsProvider_->getCaps(presence->getFrom());
-            if (presenceDiscoInfo) {
-                std::vector<std::string> features = presenceDiscoInfo->getFeatures();
-                if (!commonFeaturesInitialized) {
-                    commonFeatures = features;
-                    commonFeaturesInitialized = true;
-                }
-                else {
-                    std::vector<std::string> featuresToRemove;
-                    foreach(const std::string& feature, commonFeatures) {
-                        if (std::find(features.begin(), features.end(), feature) == features.end()) {
-                            featuresToRemove.push_back(feature);
-                        }
-                    }
-                    foreach(const std::string& featureToRemove, featuresToRemove) {
-                        commonFeatures.erase(std::remove(commonFeatures.begin(), commonFeatures.end(), featureToRemove), commonFeatures.end());
-                    }
+        // Calculate the union of disco features of all most available results and return that.
+        std::vector<DiscoInfo::ref> onlineDiscoInfos;
+        std::unordered_set<std::string> features;
+
+        // Collect relevant disco info results and the set of features.
+        for (auto&& presence : presenceOracle_->getAllPresence(jid)) {
+            if (presence->getType() == Presence::Available) {
+                DiscoInfo::ref presenceDiscoInfo = capsProvider_->getCaps(presence->getFrom());
+                if (presenceDiscoInfo) {
+                    onlineDiscoInfos.push_back(presenceDiscoInfo);
+                    features.insert(presenceDiscoInfo->getFeatures().begin(), presenceDiscoInfo->getFeatures().end());
                 }
             }
         }
-        discoInfo = std::make_shared<DiscoInfo>();
 
-        foreach(const std::string& commonFeature, commonFeatures) {
-            discoInfo->addFeature(commonFeature);
+        // Calculate supportedFeaturesMap.
+        for (auto&& feature : features) {
+            Tristate supported = Yes;
+            for (auto&& discoInfo : onlineDiscoInfos) {
+                if (!discoInfo->hasFeature(feature)) {
+                    supported = Maybe;
+                    break;
+                }
+            }
+            supportedFeatures[feature] = supported;
         }
     }
     else {
         // Return the disco result of the full JID.
-        discoInfo = capsProvider_->getCaps(jid);
+        auto discoInfo = capsProvider_->getCaps(jid);
+        if (discoInfo) {
+            for (auto&& feature : discoInfo->getFeatures()) {
+                supportedFeatures[feature] = Yes;
+            }
+        }
     }
 
-    return discoInfo;
+    return supportedFeatures;
 }
 
-Tristate FeatureOracle::isFeatureSupported(const JID& jid, const std::string& feature) {
-    DiscoInfo::ref discoInfo = getDiscoResultForJID(jid);
-    if (discoInfo) {
-        return discoInfo->hasFeature(feature) ? Yes : No;
-    }
-    else {
-        return Maybe;
+Tristate FeatureOracle::isFeatureSupported(const std::unordered_map<std::string, Tristate>& supportedFeatures, const std::string& feature) {
+    Tristate supported = No;
+    auto lookupResult = supportedFeatures.find(feature);
+    if (lookupResult != supportedFeatures.end()) {
+        supported = lookupResult->second;
     }
+    return supported;
 }
 
 }
diff --git a/Swiften/Disco/FeatureOracle.h b/Swiften/Disco/FeatureOracle.h
index d434e86..be0cd6f 100644
--- a/Swiften/Disco/FeatureOracle.h
+++ b/Swiften/Disco/FeatureOracle.h
@@ -1,11 +1,14 @@
 /*
- * Copyright (c) 2015 Isode Limited.
+ * Copyright (c) 2015-2016 Isode Limited.
  * All rights reserved.
  * See the COPYING file for more information.
  */
 
 #pragma once
 
+#include <unordered_map>
+#include <unordered_set>
+
 #include <Swiften/Base/API.h>
 #include <Swiften/Base/Tristate.h>
 #include <Swiften/Elements/DiscoInfo.h>
@@ -27,16 +30,19 @@ class SWIFTEN_API FeatureOracle {
         Tristate isFileTransferSupported(const JID& jid);
         Tristate isMessageReceiptsSupported(const JID& jid);
         Tristate isMessageCorrectionSupported(const JID& jid);
+        Tristate isWhiteboardSupported(const JID& jid);
+
+        JID getMostAvailableClientForFileTrasfer(const JID& bareJID);
 
     private:
         /**
          * @brief getDiscoResultForJID returns a  shared reference to a DiscoInfo representing features supported by the jid.
-         * @param jid The JID to return the DiscoInfo::ref for.
-         * @return DiscoResult::ref
+         * @param jid The JID to return an std::unordered_map<std::string, Tristate> for.
+         * @return std::unordered_map<std::string, Tristate>
          */
-        DiscoInfo::ref getDiscoResultForJID(const JID& jid);
+        std::unordered_map<std::string, Tristate> getFeaturesForJID(const JID& jid);
 
-        Tristate isFeatureSupported(const JID& jid, const std::string& feature);
+        Tristate isFeatureSupported(const std::unordered_map<std::string, Tristate>& supportedFeatures, const std::string& feature);
 
     private:
         EntityCapsProvider* capsProvider_;
diff --git a/Swiften/Disco/UnitTest/FeatureOracleTest.cpp b/Swiften/Disco/UnitTest/FeatureOracleTest.cpp
new file mode 100644
index 0000000..e5ff09b
--- /dev/null
+++ b/Swiften/Disco/UnitTest/FeatureOracleTest.cpp
@@ -0,0 +1,151 @@
+/*
+ * Copyright (c) 2016 Isode Limited.
+ * All rights reserved.
+ * See the COPYING file for more information.
+ */
+
+#include <vector>
+
+#include <boost/bind.hpp>
+
+#include <cppunit/extensions/HelperMacros.h>
+#include <cppunit/extensions/TestFactoryRegistry.h>
+
+#include <Swiften/Base/Tristate.h>
+#include <Swiften/Client/DummyStanzaChannel.h>
+#include <Swiften/Crypto/CryptoProvider.h>
+#include <Swiften/Crypto/PlatformCryptoProvider.h>
+#include <Swiften/Disco/CapsInfoGenerator.h>
+#include <Swiften/Disco/CapsProvider.h>
+#include <Swiften/Disco/EntityCapsManager.h>
+#include <Swiften/Disco/FeatureOracle.h>
+#include <Swiften/Elements/CapsInfo.h>
+#include <Swiften/Presence/PresenceOracle.h>
+#include <Swiften/Roster/XMPPRosterImpl.h>
+
+using namespace Swift;
+
+class FeatureOracleTest : public CppUnit::TestFixture {
+        CPPUNIT_TEST_SUITE(FeatureOracleTest);
+        CPPUNIT_TEST(testMergeAvailableResourcesForFeatures);
+        CPPUNIT_TEST(testMostAvailableFileTransferClient);
+        CPPUNIT_TEST_SUITE_END();
+
+    public:
+        void setUp() {
+            crypto_ = std::shared_ptr<CryptoProvider>(PlatformCryptoProvider::create());
+            dummyStanzaChannel_ = new DummyStanzaChannel();
+            xmppRosterImpl_ = new XMPPRosterImpl();
+            dummyCapsProvider_ = new DummyCapsProvider();
+            entityCapsManager_ = new EntityCapsManager(dummyCapsProvider_, dummyStanzaChannel_);
+            presenceOracle_ = new PresenceOracle(dummyStanzaChannel_, xmppRosterImpl_);
+            featureOracle_ = new FeatureOracle(entityCapsManager_, presenceOracle_);
+        }
+
+        void tearDown() {
+            delete featureOracle_;
+            delete presenceOracle_;
+            delete entityCapsManager_;
+            delete dummyCapsProvider_;
+            delete xmppRosterImpl_;
+            delete dummyStanzaChannel_;
+        }
+
+        void simulateIncomingPresence(const JID& from, Presence::Type type, StatusShow::Type status, const DiscoInfo::ref& disco, const std::vector<Payload::ref>& additionalPayloads = {}) {
+             auto capsInfo = std::make_shared<CapsInfo>(CapsInfoGenerator("http://example.com", crypto_.get()).generateCapsInfo(*disco.get()));
+             dummyCapsProvider_->caps[capsInfo->getVersion()] = disco;
+
+             Presence::ref capsNotifyPresence = std::make_shared<Presence>();
+             capsNotifyPresence->setType(type);
+             capsNotifyPresence->setFrom(from);
+             capsNotifyPresence->setShow(status);
+             capsNotifyPresence->addPayload(capsInfo);
+
+             capsNotifyPresence->addPayloads(additionalPayloads);
+
+             xmppRosterImpl_->addContact(from, "Foo", {}, RosterItemPayload::Both);
+             dummyStanzaChannel_->onPresenceReceived(capsNotifyPresence);
+        }
+
+        DiscoInfo::ref fileTransferSupportingDisco() {
+            DiscoInfo::ref discoInfo = std::make_shared<DiscoInfo>();
+            discoInfo->addFeature(DiscoInfo::JingleFeature);
+            discoInfo->addFeature(DiscoInfo::JingleFTFeature);
+            discoInfo->addFeature(DiscoInfo::JingleTransportsS5BFeature);
+            discoInfo->addFeature(DiscoInfo::JingleTransportsIBBFeature);
+            return discoInfo;
+        }
+
+        DiscoInfo::ref noFileTransferSupportingDisco() {
+            DiscoInfo::ref discoInfo = std::make_shared<DiscoInfo>();
+            discoInfo->addFeature(DiscoInfo::JingleFeature);
+            return discoInfo;
+        }
+
+        void testMergeAvailableResourcesForFeatures() {
+            CPPUNIT_ASSERT_EQUAL(No, featureOracle_->isFileTransferSupported(baseJID));
+
+            simulateIncomingPresence(noFileTransferJID, Presence::Available, StatusShow::Online, noFileTransferSupportingDisco());
+
+            CPPUNIT_ASSERT_EQUAL(size_t(1), presenceOracle_->getAllPresence(baseJID).size());
+            CPPUNIT_ASSERT_EQUAL(No, featureOracle_->isFileTransferSupported(baseJID));
+
+            simulateIncomingPresence(fileTransferJID, Presence::Available, StatusShow::Online, fileTransferSupportingDisco());
+
+            CPPUNIT_ASSERT_EQUAL(size_t(2), presenceOracle_->getAllPresence(baseJID).size());
+            CPPUNIT_ASSERT_EQUAL(Maybe, featureOracle_->isFileTransferSupported(baseJID));
+
+            simulateIncomingPresence(noFileTransferJID, Presence::Unavailable, StatusShow::None, noFileTransferSupportingDisco());
+
+            CPPUNIT_ASSERT_EQUAL(size_t(1), presenceOracle_->getAllPresence(baseJID).size());
+            CPPUNIT_ASSERT_EQUAL(Yes, featureOracle_->isFileTransferSupported(baseJID));
+
+            simulateIncomingPresence(fileTransferJID, Presence::Unavailable, StatusShow::None, fileTransferSupportingDisco());
+
+            CPPUNIT_ASSERT_EQUAL(size_t(1), presenceOracle_->getAllPresence(baseJID).size());
+            CPPUNIT_ASSERT_EQUAL(No, featureOracle_->isFileTransferSupported(baseJID));
+        }
+
+        void testMostAvailableFileTransferClient() {
+            simulateIncomingPresence(fileTransferJID, Presence::Available, StatusShow::DND, fileTransferSupportingDisco());
+
+            CPPUNIT_ASSERT_EQUAL(fileTransferJID, featureOracle_->getMostAvailableClientForFileTrasfer(baseJID));
+
+            simulateIncomingPresence(noFileTransferJID, Presence::Available, StatusShow::Online, noFileTransferSupportingDisco());
+
+            CPPUNIT_ASSERT_EQUAL(fileTransferJID, featureOracle_->getMostAvailableClientForFileTrasfer(baseJID));
+
+            auto moreAvailableJID = baseJID.withResource("moreAvailableFt");
+            simulateIncomingPresence(moreAvailableJID, Presence::Available, StatusShow::Online, fileTransferSupportingDisco());
+
+            CPPUNIT_ASSERT_EQUAL(moreAvailableJID, featureOracle_->getMostAvailableClientForFileTrasfer(baseJID));
+        }
+
+    private:
+        struct DummyCapsProvider : public CapsProvider {
+            virtual DiscoInfo::ref getCaps(const std::string& hash) const {
+                std::map<std::string, DiscoInfo::ref>::const_iterator i = caps.find(hash);
+                if (i != caps.end()) {
+                    return i->second;
+                }
+                return DiscoInfo::ref();
+            }
+
+            std::map<std::string, DiscoInfo::ref> caps;
+        };
+
+    private:
+        JID baseJID = "test@example.com";
+        JID fileTransferJID = baseJID.withResource("fileTransfer");
+        JID noFileTransferJID = baseJID.withResource("noFileTransfer");
+
+        std::shared_ptr<CryptoProvider> crypto_;
+        DummyCapsProvider* dummyCapsProvider_;
+        DummyStanzaChannel* dummyStanzaChannel_;
+        EntityCapsManager* entityCapsManager_;
+        FeatureOracle* featureOracle_;
+        PresenceOracle* presenceOracle_;
+        XMPPRosterImpl* xmppRosterImpl_;
+};
+
+CPPUNIT_TEST_SUITE_REGISTRATION(FeatureOracleTest);