refactor: deduplicate IRC parsing (#5678)

src/messages/MessageSimilarity.cpp

@@ -0,0 +1,121 @@
+#include "messages/MessageSimilarity.hpp"
+
+#include "Application.hpp"
+#include "controllers/accounts/AccountController.hpp"
+#include "messages/LimitedQueueSnapshot.hpp"  // IWYU pragma: keep
+#include "providers/twitch/TwitchAccount.hpp"
+#include "singletons/Settings.hpp"
+
+#include <algorithm>
+#include <vector>
+
+namespace {
+
+using namespace chatterino;
+
+float relativeSimilarity(QStringView str1, QStringView str2)
+{
+    using SizeType = QStringView::size_type;
+
+    // Longest Common Substring Problem
+    std::vector<std::vector<int>> tree(str1.size(),
+                                       std::vector<int>(str2.size(), 0));
+    int z = 0;
+
+    for (SizeType i = 0; i < str1.size(); ++i)
+    {
+        for (SizeType j = 0; j < str2.size(); ++j)
+        {
+            if (str1[i] == str2[j])
+            {
+                if (i == 0 || j == 0)
+                {
+                    tree[i][j] = 1;
+                }
+                else
+                {
+                    tree[i][j] = tree[i - 1][j - 1] + 1;
+                }
+                z = std::max(tree[i][j], z);
+            }
+            else
+            {
+                tree[i][j] = 0;
+            }
+        }
+    }
+
+    // ensure that no div by 0
+    if (z == 0)
+    {
+        return 0.F;
+    }
+
+    auto div = std::max<>({static_cast<SizeType>(1), str1.size(), str2.size()});
+
+    return float(z) / float(div);
+}
+
+template <std::ranges::bidirectional_range T>
+float inMessages(const MessagePtr &msg, const T &messages)
+{
+    float similarityPercent = 0.0F;
+
+    for (const auto &prevMsg :
+         messages | std::views::reverse |
+             std::views::take(getSettings()->hideSimilarMaxMessagesToCheck))
+    {
+        if (prevMsg->parseTime.secsTo(QTime::currentTime()) >=
+            getSettings()->hideSimilarMaxDelay)
+        {
+            break;
+        }
+        if (getSettings()->hideSimilarBySameUser &&
+            msg->loginName != prevMsg->loginName)
+        {
+            continue;
+        }
+        similarityPercent = std::max(
+            similarityPercent,
+            relativeSimilarity(msg->messageText, prevMsg->messageText));
+    }
+
+    return similarityPercent;
+}
+
+}  // namespace
+
+namespace chatterino {
+
+template <std::ranges::bidirectional_range T>
+void setSimilarityFlags(const MessagePtr &message, const T &messages)
+{
+    if (getSettings()->similarityEnabled)
+    {
+        bool isMyself =
+            message->loginName ==
+            getApp()->getAccounts()->twitch.getCurrent()->getUserName();
+        bool hideMyself = getSettings()->hideSimilarMyself;
+
+        if (isMyself && !hideMyself)
+        {
+            return;
+        }
+
+        if (inMessages(message, messages) > getSettings()->similarityPercentage)
+        {
+            message->flags.set(MessageFlag::Similar);
+            if (getSettings()->colorSimilarDisabled)
+            {
+                message->flags.set(MessageFlag::Disabled);
+            }
+        }
+    }
+}
+
+template void setSimilarityFlags<std::vector<MessagePtr>>(
+    const MessagePtr &msg, const std::vector<MessagePtr> &messages);
+template void setSimilarityFlags<LimitedQueueSnapshot<MessagePtr>>(
+    const MessagePtr &msg, const LimitedQueueSnapshot<MessagePtr> &messages);
+
+}  // namespace chatterino

src/messages/MessageSimilarity.hpp

@@ -0,0 +1,11 @@
+#pragma once
+
+#include "messages/Message.hpp"
+
+#include <ranges>
+namespace chatterino {
+
+template <std::ranges::bidirectional_range T>
+void setSimilarityFlags(const MessagePtr &message, const T &messages);
+
+}  // namespace chatterino

src/messages/MessageSink.hpp

@@ -0,0 +1,67 @@
+#pragma once
+
+#include "common/enums/MessageContext.hpp"
+#include "common/FlagsEnum.hpp"
+#include "messages/MessageFlag.hpp"
+
+#include <memory>
+#include <optional>
+
+class QStringView;
+class QTime;
+
+namespace chatterino {
+
+struct Message;
+using MessagePtr = std::shared_ptr<const Message>;
+
+enum class MessageSinkTrait : uint8_t {
+    None = 0,
+
+    /// Messages with the `Highlighted` and `ShowInMentions` flags should be
+    /// added to the global mentions channel when encountered.
+    AddMentionsToGlobalChannel = 1 << 0,
+
+    /// A channel-point redemption whose reward is not yet known should not be
+    /// added to this sink, but queued in the corresponding TwitchChannel
+    /// (`addQueuedRedemption`).
+    RequiresKnownChannelPointReward = 1 << 1,
+};
+using MessageSinkTraits = FlagsEnum<MessageSinkTrait>;
+
+/// A generic interface for a managed buffer of `Message`s
+class MessageSink
+{
+public:
+    virtual ~MessageSink() = default;
+
+    /// Add a message to this sink
+    ///
+    /// @param message The message to add (non-null)
+    /// @param ctx The context in which this message is being added.
+    /// @param overridingFlags
+    virtual void addMessage(
+        MessagePtr message, MessageContext ctx,
+        std::optional<MessageFlags> overridingFlags = std::nullopt) = 0;
+
+    /// Adds a timeout message or merges it into an existing one
+    virtual void addOrReplaceTimeout(MessagePtr clearchatMessage,
+                                     QTime now) = 0;
+
+    /// Flags all messages as `Disabled`
+    virtual void disableAllMessages() = 0;
+
+    /// Searches for similar messages and flags this message as similar
+    /// (based on the current settings).
+    virtual void applySimilarityFilters(const MessagePtr &message) const = 0;
+
+    /// @brief Searches for a message by an ID
+    ///
+    /// If there is no message found, an empty shared-pointer is returned.
+    virtual MessagePtr findMessageByID(QStringView id) = 0;
+
+    /// Behaviour to be exercised when parsing/building messages for this sink.
+    virtual MessageSinkTraits sinkTraits() const = 0;
+};
+
+}  // namespace chatterino