Refactor recent messages API (Chatterino#4763)

This exposes internal functions for testing by splitting the implementation & internal API into separate files

CHANGELOG.md

@@ -51,6 +51,7 @@
 - Dev: Replace our QObjectRef class with Qt's QPointer class. (#4666)
 - Dev: Fixed warnings about QWidgets already having a QLayout. (#4672)
 - Dev: Fixed undefined behavior when loading non-existant credentials. (#4673)
+- Dev: Small refactor of the recent-messages API, splitting its internal API and its internal implementation up into separate files. (#4763)
 - Dev: Added support for compiling with `sccache`. (#4678)
 - Dev: Added `sccache` in Windows CI. (#4678)
 - Dev: Moved preprocessor Git and date definitions to executables only. (#4681)

src/CMakeLists.txt

@@ -238,8 +238,6 @@ set(SOURCE_FILES
         providers/LinkResolver.hpp
         providers/NetworkConfigurationProvider.cpp
         providers/NetworkConfigurationProvider.hpp
-        providers/RecentMessagesApi.cpp
-        providers/RecentMessagesApi.hpp
 
         providers/seventv/SeventvBadges.cpp
         providers/seventv/SeventvBadges.hpp
@@ -305,6 +303,11 @@ set(SOURCE_FILES
         providers/liveupdates/BasicPubSubManager.hpp
         providers/liveupdates/BasicPubSubWebsocket.hpp
 
+        providers/recentmessages/Api.cpp
+        providers/recentmessages/Api.hpp
+        providers/recentmessages/Impl.cpp
+        providers/recentmessages/Impl.hpp
+
         providers/seventv/SeventvAPI.cpp
         providers/seventv/SeventvAPI.hpp
         providers/seventv/SeventvBadges.cpp

src/providers/recentmessages/Api.cpp

@@ -0,0 +1,91 @@
+#include "providers/recentmessages/Api.hpp"
+
+#include "common/NetworkRequest.hpp"
+#include "common/NetworkResult.hpp"
+#include "common/QLogging.hpp"
+#include "providers/recentmessages/Impl.hpp"
+#include "providers/twitch/TwitchMessageBuilder.hpp"
+#include "util/PostToThread.hpp"
+
+namespace {
+
+// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
+const auto &LOG = chatterinoRecentMessages;
+
+}  // namespace
+
+namespace chatterino::recentmessages {
+
+using namespace recentmessages::detail;
+
+void load(const QString &channelName, std::weak_ptr<Channel> channelPtr,
+          ResultCallback onLoaded, ErrorCallback onError)
+{
+    qCDebug(LOG) << "Loading recent messages for" << channelName;
+
+    const auto url = constructRecentMessagesUrl(channelName);
+
+    NetworkRequest(url)
+        .onSuccess([channelPtr, onLoaded](const auto &result) -> Outcome {
+            auto shared = channelPtr.lock();
+            if (!shared)
+            {
+                return Failure;
+            }
+
+            qCDebug(LOG) << "Successfully loaded recent messages for"
+                         << shared->getName();
+
+            auto root = result.parseJson();
+            auto parsedMessages = parseRecentMessages(root);
+
+            // build the Communi messages into chatterino messages
+            auto builtMessages =
+                buildRecentMessages(parsedMessages, shared.get());
+
+            postToThread([shared = std::move(shared), root = std::move(root),
+                          messages = std::move(builtMessages),
+                          onLoaded]() mutable {
+                // Notify user about a possible gap in logs if it returned some messages
+                // but isn't currently joined to a channel
+                const auto errorCode = root.value("error_code").toString();
+                if (!errorCode.isEmpty())
+                {
+                    qCDebug(LOG)
+                        << QString("Got error from API: error_code=%1, "
+                                   "channel=%2")
+                               .arg(errorCode, shared->getName());
+                    if (errorCode == "channel_not_joined" && !messages.empty())
+                    {
+                        shared->addMessage(makeSystemMessage(
+                            "Message history service recovering, there may "
+                            "be gaps in the message history."));
+                    }
+                }
+
+                onLoaded(messages);
+            });
+
+            return Success;
+        })
+        .onError([channelPtr, onError](const NetworkResult &result) {
+            auto shared = channelPtr.lock();
+            if (!shared)
+            {
+                return;
+            }
+
+            qCDebug(LOG) << "Failed to load recent messages for"
+                         << shared->getName();
+
+            shared->addMessage(makeSystemMessage(
+                QStringLiteral(
+                    "Message history service unavailable (Error: %1)")
+                    .arg(result.formatError())));
+
+            onError();
+        })
+        .execute();
+}
+
+}  // namespace chatterino::recentmessages