feat(macos/tray): allow tray icon paths to be set at runtime from .app bundle (#4711)

src/system_tray.cpp

@@ -23,7 +23,9 @@
     #define TRAY_ICON_PLAYING WEB_DIR "images/sunshine-playing-16.png"
     #define TRAY_ICON_PAUSING WEB_DIR "images/sunshine-pausing-16.png"
     #define TRAY_ICON_LOCKED WEB_DIR "images/sunshine-locked-16.png"
+    #include <CoreFoundation/CoreFoundation.h>
     #include <dispatch/dispatch.h>
+    #include <unordered_map>
   #endif
 
   // standard includes
@@ -127,6 +129,58 @@ namespace system_tray {
     .allIconPaths = {TRAY_ICON, TRAY_ICON_LOCKED, TRAY_ICON_PLAYING, TRAY_ICON_PAUSING},
   };
 
+  const char *GetResourcePath(const char *relativePath) {
+  #ifdef __APPLE__
+    if (!relativePath || !*relativePath) {
+      return nullptr;
+    }
+
+    // Simple cache ensures our string pointers live forever
+    static std::unordered_map<std::string, std::string> g_cache;
+    auto search = g_cache.find(relativePath);
+    if (search != g_cache.end()) {
+      return search->second.c_str();
+    }
+
+    // If we're running from an .app bundle, get the internal Resources dir
+    CFBundleRef bundle = CFBundleGetMainBundle();
+    if (!bundle) {
+      return relativePath;
+    }
+
+    CFURLRef resourcesURL = CFBundleCopyResourcesDirectoryURL(bundle);
+    if (!resourcesURL) {
+      return relativePath;
+    }
+
+    char resourcesPath[PATH_MAX];
+    bool ok = CFURLGetFileSystemRepresentation(
+      resourcesURL,
+      true,
+      reinterpret_cast<UInt8 *>(resourcesPath),
+      sizeof(resourcesPath)
+    );
+    CFRelease(resourcesURL);
+    if (!ok) {
+      return relativePath;
+    }
+
+    std::string full;
+    if (relativePath && relativePath[0] == '/') {
+      full = relativePath;
+    } else {
+      full = std::string(resourcesPath) + "/" + relativePath;
+    }
+
+    BOOST_LOG(debug) << "System Tray: using " << full << " for icon path";
+
+    auto [it, inserted] = g_cache.emplace(relativePath, std::move(full));
+    return it->second.c_str();
+  #else
+    return relativePath;
+  #endif
+  }
+
   int init_tray() {
   #ifdef _WIN32
     // If we're running as SYSTEM, Explorer.exe will not have permission to open our thread handle
@@ -190,6 +244,16 @@ namespace system_tray {
     }
   #endif
 
+  #ifdef __APPLE__
+    // if these icon paths are relative, resolve to internal .app Resources path
+    tray.allIconPaths[0] = GetResourcePath(TRAY_ICON);
+    tray.allIconPaths[1] = GetResourcePath(TRAY_ICON_LOCKED);
+    tray.allIconPaths[2] = GetResourcePath(TRAY_ICON_PLAYING);
+    tray.allIconPaths[3] = GetResourcePath(TRAY_ICON_PAUSING);
+
+    tray.icon = tray.allIconPaths[0];
+  #endif
+
     if (tray_init(&tray) < 0) {
       BOOST_LOG(warning) << "Failed to create system tray"sv;
       return 1;