some thoughts on detecting condition for enablining or showing the button for encryption in chat window

shared/CMakeLists.txt

@@ -14,6 +14,7 @@ set(SOURCE_FILES
   keyinfo.cpp
   info.cpp
   clientid.cpp
+  trustsummary.cpp
 )
 
 set(HEADER_FILES
@@ -35,6 +36,7 @@ set(HEADER_FILES
   keyinfo.h
   info.h
   clientid.h
+  trustsummary.h
 )
 
 target_sources(squawk PRIVATE

shared/trustsummary.cpp

@@ -0,0 +1,140 @@
+// Squawk messenger. 
+// Copyright (C) 2019  Yury Gubich <blue@macaw.me>
+// 
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+// 
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+// 
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+#include "trustsummary.h"
+
+const std::set<Shared::TrustLevel> Shared::TrustSummary::trustedLevels({
+    Shared::TrustLevel::authenticated,
+    Shared::TrustLevel::automaticallyTrusted,
+    Shared::TrustLevel::manuallyTrusted
+});
+const std::set<Shared::TrustLevel> Shared::TrustSummary::untrustedLevels({
+    Shared::TrustLevel::undecided,
+    Shared::TrustLevel::automaticallyDistrusted,
+    Shared::TrustLevel::manuallyDistrusted
+});
+
+Shared::TrustSummary::TrustSummary():
+    data()
+{}
+
+void Shared::TrustSummary::set(Shared::EncryptionProtocol protocol, Shared::TrustLevel level, uint8_t amount) {
+    Data::iterator itr = data.find(protocol);
+    if (itr == data.end()) {
+        if (amount == 0)
+            return;
+
+        itr = data.insert(std::make_pair(protocol, Amounts())).first;
+    }
+
+    Amounts& am = itr->second;
+    Amounts::iterator aitr = am.find(level);
+    if (aitr == am.end()) {
+        if (amount == 0)
+            return;
+
+        am.emplace(level, amount);
+        return;
+    }
+    if (amount == 0) {
+        if (am.size() == 1)
+            data.erase(itr);
+        else
+            am.erase(aitr);
+
+        return;
+    }
+    aitr->second = amount;
+}
+
+uint8_t Shared::TrustSummary::amount(Shared::EncryptionProtocol protocol, Shared::TrustLevel level) const {
+    Data::const_iterator itr = data.find(protocol);
+    if (itr == data.end())
+        return 0;
+
+    const Amounts& am = itr->second;
+    Amounts::const_iterator aitr = am.find(level);
+    if (aitr == am.end())
+        return 0;
+
+    return aitr->second;
+}
+
+uint8_t Shared::TrustSummary::increment(Shared::EncryptionProtocol protocol, Shared::TrustLevel level) {
+    Data::iterator itr = data.find(protocol);
+    if (itr == data.end())
+        itr = data.insert(std::make_pair(protocol, Amounts())).first;
+
+    Amounts& am = itr->second;
+    Amounts::iterator aitr = am.find(level);
+    if (aitr == am.end()) {
+        am.emplace(level, 1);
+        return 1;
+    }
+    uint8_t& value = aitr->second;
+    return ++value;
+}
+
+uint8_t Shared::TrustSummary::decrement(Shared::EncryptionProtocol protocol, Shared::TrustLevel level) {
+    Data::iterator itr = data.find(protocol);
+    if (itr == data.end())
+        return 0;                   //should never happen, shall I better throw an exception?
+
+    Amounts& am = itr->second;
+    Amounts::iterator aitr = am.find(level);
+    if (aitr == am.end())
+        return 0;                   //should never happen, shall I better throw an exception?
+
+    uint8_t& value = aitr->second;
+    uint8_t result = --value;
+    if (value == 0) {
+        if (am.size() == 1)
+            data.erase(itr);
+        else
+            am.erase(aitr);
+    }
+    return result;
+}
+
+bool Shared::TrustSummary::hasKeys(Shared::EncryptionProtocol protocol) const {
+    return data.count(protocol) > 0;
+}
+
+bool Shared::TrustSummary::hasTrustedKeys(Shared::EncryptionProtocol protocol) const {
+    Data::const_iterator itr = data.find(protocol);
+    if (itr == data.end())
+        return false;
+
+    for (const std::pair<const TrustLevel, uint8_t>& pair : itr->second) {
+        if (trustedLevels.count(pair.first) > 0)
+            return true;
+    }
+
+    return false;
+}
+
+bool Shared::TrustSummary::hasUntrustedKeys(Shared::EncryptionProtocol protocol) const {
+        Data::const_iterator itr = data.find(protocol);
+    if (itr == data.end())
+        return false;
+
+    for (const std::pair<const TrustLevel, uint8_t>& pair : itr->second) {
+        if (untrustedLevels.count(pair.first) > 0)
+            return true;
+    }
+
+    return false;
+}

shared/trustsummary.h

@@ -0,0 +1,51 @@
+// Squawk messenger. 
+// Copyright (C) 2019  Yury Gubich <blue@macaw.me>
+// 
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+// 
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+// 
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+#ifndef SHARED_TRUSTSUMMARY_H
+#define SHARED_TRUSTSUMMARY_H
+
+#include <map>
+#include <set>
+
+#include "enums.h"
+
+namespace Shared {
+
+class TrustSummary {
+public:
+    TrustSummary();
+
+    void set(EncryptionProtocol protocol, TrustLevel level, uint8_t amount);
+    uint8_t increment(EncryptionProtocol protocol, TrustLevel level);
+    uint8_t decrement(EncryptionProtocol protocol, TrustLevel level);
+
+    uint8_t amount(EncryptionProtocol protocol, TrustLevel level) const;
+    bool hasKeys(EncryptionProtocol protocol) const;
+    bool hasTrustedKeys(EncryptionProtocol protocol) const;
+    bool hasUntrustedKeys(EncryptionProtocol protocol) const;
+
+private:
+    typedef std::map<TrustLevel, uint8_t> Amounts;
+    typedef std::map<EncryptionProtocol, Amounts> Data;
+
+    Data data;
+    static const std::set<TrustLevel> trustedLevels;
+    static const std::set<TrustLevel> untrustedLevels;
+};
+
+}
+
+#endif // SHARED_TRUSTSUMMARY_H