Improve Twitch PubSub connection reliability (#3643)

Co-authored-by: Rasmus Karlsson <rasmus.karlsson@pajlada.com>

src/providers/twitch/PubSubClient.hpp

@@ -0,0 +1,74 @@
+#pragma once
+
+#include "providers/twitch/PubSubClientOptions.hpp"
+#include "providers/twitch/PubSubMessages.hpp"
+#include "providers/twitch/PubSubWebsocket.hpp"
+
+#include <QString>
+#include <pajlada/signals/signal.hpp>
+
+#include <atomic>
+#include <vector>
+
+namespace chatterino {
+
+struct TopicData {
+    QString topic;
+    bool authed{false};
+    bool persistent{false};
+};
+
+struct Listener : TopicData {
+    bool confirmed{false};
+};
+
+class PubSubClient : public std::enable_shared_from_this<PubSubClient>
+{
+public:
+    struct UnlistenPrefixResponse {
+        std::vector<QString> topics;
+        QString nonce;
+    };
+
+    // The max amount of topics we may listen to with a single connection
+    static constexpr std::vector<QString>::size_type MAX_LISTENS = 50;
+
+    PubSubClient(WebsocketClient &_websocketClient, WebsocketHandle _handle,
+                 const PubSubClientOptions &clientOptions);
+
+    void start();
+    void stop();
+
+    void close(const std::string &reason,
+               websocketpp::close::status::value code =
+                   websocketpp::close::status::normal);
+
+    bool listen(PubSubListenMessage msg);
+    UnlistenPrefixResponse unlistenPrefix(const QString &prefix);
+
+    void handleListenResponse(const PubSubMessage &message);
+    void handleUnlistenResponse(const PubSubMessage &message);
+
+    void handlePong();
+
+    bool isListeningToTopic(const QString &topic);
+
+    std::vector<Listener> getListeners() const;
+
+private:
+    void ping();
+    bool send(const char *payload);
+
+    WebsocketClient &websocketClient_;
+    WebsocketHandle handle_;
+    uint16_t numListens_ = 0;
+
+    std::vector<Listener> listeners_;
+
+    std::atomic<bool> awaitingPong_{false};
+    std::atomic<bool> started_{false};
+
+    const PubSubClientOptions &clientOptions_;
+};
+
+}  // namespace chatterino