Added KWin workaround to get current window title

src/KwinWorkaround.cpp

@@ -0,0 +1,76 @@
+#include "../include/KwinWorkaround.hpp"
+
+#include <cstddef>
+#include <iostream>
+#include <sys/types.h>
+#include <thread>
+#include <cstdlib>
+#include <cstring>
+#include <array>
+#include <unistd.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+
+namespace gsr {
+    static ActiveKwinWindow *active_kwin_window = nullptr;
+    static bool kwin_helper_thread_started = false;
+
+    std::string get_current_kwin_window_title() {
+        if (active_kwin_window == nullptr) {
+            return "Game";
+        }
+
+        return active_kwin_window->title;
+    }
+
+    void kwin_script_thread() {
+        const bool inside_flatpak = getenv("FLATPAK_ID") != NULL;
+        if(inside_flatpak) {
+            std::cerr << "Sorry, KWin workaround isn't available for Flatpak yet. Stay tuned!\n";
+            return;
+        }
+
+        FILE* pipe = popen("/usr/bin/gsr-kwin-helper", "r");
+        if (!pipe) {
+            std::cerr << "Failed to start gsr-kwin-helper process\n";
+            return;
+        }
+
+        std::cerr << "Started a KWin helper thread\n";
+
+        char buffer[4096];
+        const std::string prefix = "Active window title set to: ";
+
+        while (fgets(buffer, sizeof(buffer), pipe) != nullptr) {
+            std::string line(buffer);
+
+            if (!line.empty() && line.back() == '\n') {
+                line.pop_back();
+            }
+
+            size_t pos = line.find(prefix);
+            if (pos != std::string::npos) {
+                std::string title = line.substr(pos + prefix.length());
+                active_kwin_window->title = title;
+            }
+        }
+
+        pclose(pipe);
+    }
+
+    void start_kwin_helper_thread() {
+        if (kwin_helper_thread_started) {
+            return;
+        }
+
+        if (active_kwin_window == nullptr) {
+            active_kwin_window = new ActiveKwinWindow();
+        }
+
+        kwin_helper_thread_started = true;
+
+        std::thread([&] {
+            kwin_script_thread();
+        }).detach();
+    }
+}