feat: add REPL for plugins (#6120)

This can be enabled by setting the `.plugins.repl.enabled` setting to true


Close Chatterino and make a backup of your settings.json before attempting any modifications.
```json5
{
  "plugins": {
    "repl": {
      "enabled": true,
    },
  },
}
```

src/controllers/plugins/LuaAPI.cpp

@@ -31,19 +31,6 @@
 namespace {
 using namespace chatterino;
 
-void logHelper(lua_State *L, Plugin *pl, QDebug stream,
-               const sol::variadic_args &args)
-{
-    stream.noquote();
-    stream << "[" + pl->id + ":" + pl->meta.name + "]";
-    for (const auto &arg : args)
-    {
-        stream << lua::toString(L, arg.stack_index());
-        // Remove this from our stack
-        lua_pop(L, 1);
-    }
-}
-
 QDebug qdebugStreamForLogLevel(lua::api::LogLevel lvl)
 {
     auto base =
@@ -101,7 +88,7 @@ void c2_log(ThisPluginState L, LogLevel lvl, sol::variadic_args args)
     lua::StackGuard guard(L);
     {
         QDebug stream = qdebugStreamForLogLevel(lvl);
-        logHelper(L, L.plugin(), stream, args);
+        L.plugin()->log(L.state(), lvl, std::move(stream), args);
     }
 }
 
@@ -261,7 +248,7 @@ void g_print(ThisPluginState L, sol::variadic_args args)
         (QMessageLogger(QT_MESSAGELOG_FILE, QT_MESSAGELOG_LINE,
                         QT_MESSAGELOG_FUNC, chatterinoLua().categoryName())
              .debug());
-    logHelper(L, L.plugin(), stream, args);
+    L.plugin()->log(L.state(), LogLevel::Info, std::move(stream), args);
 }
 
 void package_loadlib(sol::variadic_args args)

src/controllers/plugins/Plugin.cpp

@@ -218,6 +218,8 @@ std::unordered_set<QString> Plugin::listRegisteredCommands()
 
 Plugin::~Plugin()
 {
+    this->onUnloaded();
+
     for (auto *timer : this->activeTimeouts)
     {
         QObject::disconnect(timer, nullptr, nullptr, nullptr);
@@ -293,6 +295,35 @@ bool Plugin::hasHTTPPermissionFor(const QUrl &url)
     });
 }
 
+void Plugin::log(lua_State *L, lua::api::LogLevel level, QDebug stream,
+                 const sol::variadic_args &args)
+{
+    stream.noquote();
+    stream << "[" + this->id + ":" + this->meta.name + "]";
+    QString fullMessage;
+    for (const auto &arg : args)
+    {
+        auto s = lua::toString(L, arg.stack_index());
+        stream << s;
+
+        if (!fullMessage.isEmpty())
+        {
+            fullMessage.append(' ');
+        }
+        fullMessage.append(s);
+
+        // Remove this from our stack
+        lua_pop(L, 1);
+    }
+
+    this->onLog(level, fullMessage);
+}
+
+sol::state_view Plugin::state()
+{
+    return {this->state_};
+}
+
 bool Plugin::hasNetworkPermission() const
 {
     return std::ranges::any_of(this->meta.permissions, [](const auto &p) {

src/controllers/plugins/Plugin.hpp

@@ -6,6 +6,7 @@
 #    include "controllers/plugins/LuaUtilities.hpp"
 #    include "controllers/plugins/PluginPermission.hpp"
 
+#    include <boost/signals2/signal.hpp>
 #    include <QDir>
 #    include <QString>
 #    include <QUrl>
@@ -21,6 +22,10 @@
 struct lua_State;
 class QTimer;
 
+namespace chatterino::lua::api {
+enum class LogLevel;
+}  // namespace chatterino::lua::api
+
 namespace chatterino {
 
 struct PluginMeta {
@@ -137,12 +142,20 @@ public:
     bool hasHTTPPermissionFor(const QUrl &url);
     bool hasNetworkPermission() const;
 
+    void log(lua_State *L, lua::api::LogLevel level, QDebug stream,
+             const sol::variadic_args &args);
+
+    sol::state_view state();
+
     std::map<lua::api::EventType, sol::protected_function> callbacks;
 
     // In-flight HTTP Requests
     // This is a lifetime hack to ensure they get deleted with the plugin. This relies on the Plugin getting deleted on reload!
     std::vector<std::shared_ptr<lua::api::HTTPRequest>> httpRequests;
 
+    boost::signals2::signal<void()> onUnloaded;
+    boost::signals2::signal<void(lua::api::LogLevel, const QString &)> onLog;
+
 private:
     QDir loadDirectory_;
     lua_State *state_;

src/controllers/plugins/PluginController.cpp

@@ -278,6 +278,8 @@ void PluginController::load(const QFileInfo &index, const QDir &pluginDir,
     }
     temp->dataDirectory().mkpath(".");
 
+    // make sure we capture log messages during load
+    this->onPluginLoaded(temp);
     qCDebug(chatterinoLua) << "Running lua file:" << index;
     int err = luaL_dofile(l, index.absoluteFilePath().toStdString().c_str());
     if (err != 0)

src/controllers/plugins/PluginController.hpp

@@ -6,6 +6,7 @@
 #    include "controllers/commands/CommandContext.hpp"
 #    include "controllers/plugins/Plugin.hpp"
 
+#    include <boost/signals2/signal.hpp>
 #    include <QDir>
 #    include <QFileInfo>
 #    include <QJsonArray>
@@ -63,6 +64,8 @@ public:
 
     WebSocketPool &webSocketPool();
 
+    boost::signals2::signal<void(Plugin *)> onPluginLoaded;
+
 private:
     void loadPlugins();
     void load(const QFileInfo &index, const QDir &pluginDir,

src/controllers/plugins/SolTypes.cpp

@@ -3,9 +3,11 @@
 
 #    include "Application.hpp"
 #    include "common/QLogging.hpp"
+#    include "controllers/plugins/LuaAPI.hpp"
 #    include "controllers/plugins/PluginController.hpp"
 
 #    include <QObject>
+#    include <QStringBuilder>
 #    include <sol/thread.hpp>
 
 namespace chatterino::lua {
@@ -27,9 +29,10 @@ Plugin *ThisPluginState::plugin()
 
 void logError(Plugin *plugin, QStringView context, const QString &msg)
 {
+    QString fullMessage = context % u" - " % msg;
     qCWarning(chatterinoLua).noquote()
-        << "[" + plugin->id + ":" + plugin->meta.name + "]" << context << "-"
-        << msg;
+        << "[" + plugin->id + ":" + plugin->meta.name + "]" << fullMessage;
+    plugin->onLog(api::LogLevel::Warning, fullMessage);
 }
 
 }  // namespace chatterino::lua