1 files changed, 54 insertions, 0 deletions
diff --git a/src/utils/nowPlaying.ts b/src/utils/nowPlaying.ts
new file mode 100644
index 0000000..a207321
--- /dev/null
+++ b/src/utils/nowPlaying.ts
@@ -0,0 +1,54 @@
+import type { FlatpakApp, RunningFlatpakApp } from "../api/lsfgApi";
+import type { GameTarget } from "../hooks/useGameConfiguration";
+
+export type NowPlayingTarget =
+  | {
+      kind: "flatpak";
+      app: FlatpakApp;
+      launcher: GameTarget | null;
+    }
+  | {
+      kind: "steam";
+      game: GameTarget;
+    };
+
+function numericValue(value: number | null | undefined): number {
+  return typeof value === "number" && Number.isFinite(value) ? value : -1;
+}
+
+function numericPid(value: string | undefined): number {
+  return value && /^\d+$/.test(value) ? Number(value) : -1;
+}
+
+export function selectMostRecentRunningFlatpak(
+  apps: FlatpakApp[],
+  runningApps: RunningFlatpakApp[],
+): FlatpakApp | null {
+  const candidates = runningApps
+    .map((running) => ({
+      running,
+      app: apps.find((app) => app.app_id === running.app_id) || null,
+    }))
+    .filter((candidate): candidate is { running: RunningFlatpakApp; app: FlatpakApp } => candidate.app !== null)
+    .sort((a, b) => {
+      if (a.running.active !== b.running.active) return a.running.active ? -1 : 1;
+      const startDifference = numericValue(b.running.start_time) - numericValue(a.running.start_time);
+      if (startDifference !== 0) return startDifference;
+      const pidDifference = numericPid(b.running.pid) - numericPid(a.running.pid);
+      if (pidDifference !== 0) return pidDifference;
+      return a.running.app_id.localeCompare(b.running.app_id);
+    });
+
+  return candidates[0]?.app || null;
+}
+
+export function resolveNowPlayingTarget(
+  runningGame: GameTarget | null,
+  runningFlatpak: FlatpakApp | null,
+): NowPlayingTarget | null {
+  if (runningFlatpak) {
+    return { kind: "flatpak", app: runningFlatpak, launcher: runningGame };
+  }
+  if (runningGame?.configured) return { kind: "steam", game: runningGame };
+  return null;
+}