1 files changed, 201 insertions, 0 deletions
diff --git a/Swiften/Disco/FeatureOracle.cpp b/Swiften/Disco/FeatureOracle.cpp
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+++ b/Swiften/Disco/FeatureOracle.cpp
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+/*
+ * Copyright (c) 2015-2017 Isode Limited.
+ * All rights reserved.
+ * See the COPYING file for more information.
+ */
+
+#include <Swiften/Disco/FeatureOracle.h>
+
+#include <algorithm>
+#include <iterator>
+#include <unordered_set>
+#include <vector>
+
+#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>
+#include <Swiften/Presence/PresenceOracle.h>
+
+namespace Swift {
+
+FeatureOracle::FeatureOracle(EntityCapsProvider* capsProvider, PresenceOracle* presenceOracle) : capsProvider_(capsProvider), presenceOracle_(presenceOracle) {
+}
+
+Tristate FeatureOracle::isFileTransferSupported(const JID& jid) {
+    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 if (isYesOrMaybe(jingleSupported) && isYesOrMaybe(jingleFTSupported) && (isYesOrMaybe(jingleTransportIBBSupported) || isYesOrMaybe(jingleTransportS5BSupported))) {
+        fileTransferSupported = Maybe;
+    }
+
+    return fileTransferSupported;
+}
+
+Tristate FeatureOracle::isMessageReceiptsSupported(const JID& jid) {
+    return isFeatureSupported(getFeaturesForJID(jid), DiscoInfo::MessageDeliveryReceiptsFeature);
+}
+
+Tristate FeatureOracle::isMessageCorrectionSupported(const JID& jid) {
+    return isFeatureSupported(getFeaturesForJID(jid), DiscoInfo::MessageCorrectionFeature);
+}
+
+Tristate FeatureOracle::isWhiteboardSupported(const JID& jid) {
+    return isFeatureSupported(getFeaturesForJID(jid), DiscoInfo::WhiteboardFeature);
+}
+
+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 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_->getCapsCached(presence->getFrom());
+                if (presenceDiscoInfo) {
+                    onlineDiscoInfos.push_back(presenceDiscoInfo);
+                    features.insert(presenceDiscoInfo->getFeatures().begin(), presenceDiscoInfo->getFeatures().end());
+                }
+            }
+        }
+
+        // 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.
+        auto discoInfo = capsProvider_->getCapsCached(jid);
+        if (discoInfo) {
+            for (auto&& feature : discoInfo->getFeatures()) {
+                supportedFeatures[feature] = Yes;
+            }
+        }
+    }
+
+    return supportedFeatures;
+}
+
+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;
+}
+
+}
+
+