feat(stats): add v1 immersion stats dashboard (#19)

src/stats-word-helper-client.ts

@@ -0,0 +1,62 @@
+export type StatsWordHelperResponse = {
+  ok: boolean;
+  noteId?: number;
+  error?: string;
+};
+
+export function createInvokeStatsWordHelperHandler(deps: {
+  createTempDir: (prefix: string) => string;
+  joinPath: (...parts: string[]) => string;
+  spawnHelper: (options: {
+    scriptPath: string;
+    responsePath: string;
+    userDataPath: string;
+    word: string;
+  }) => Promise<number>;
+  waitForResponse: (responsePath: string) => Promise<StatsWordHelperResponse>;
+  removeDir: (targetPath: string) => void;
+}) {
+  return async (options: {
+    helperScriptPath: string;
+    userDataPath: string;
+    word: string;
+  }): Promise<number> => {
+    const tempDir = deps.createTempDir('subminer-stats-word-helper-');
+    const responsePath = deps.joinPath(tempDir, 'response.json');
+
+    try {
+      const helperExitPromise = deps.spawnHelper({
+        scriptPath: options.helperScriptPath,
+        responsePath,
+        userDataPath: options.userDataPath,
+        word: options.word,
+      });
+
+      const startupResult = await Promise.race([
+        deps.waitForResponse(responsePath).then((response) => ({ kind: 'response' as const, response })),
+        helperExitPromise.then((status) => ({ kind: 'exit' as const, status })),
+      ]);
+
+      let response: StatsWordHelperResponse;
+      if (startupResult.kind === 'response') {
+        response = startupResult.response;
+      } else {
+        if (startupResult.status !== 0) {
+          throw new Error(`Stats word helper exited before response (status ${startupResult.status}).`);
+        }
+        response = await deps.waitForResponse(responsePath);
+      }
+
+      const exitStatus = await helperExitPromise;
+      if (exitStatus !== 0) {
+        throw new Error(`Stats word helper exited with status ${exitStatus}.`);
+      }
+      if (!response.ok || typeof response.noteId !== 'number') {
+        throw new Error(response.error || 'Stats word helper failed.');
+      }
+      return response.noteId;
+    } finally {
+      deps.removeDir(tempDir);
+    }
+  };
+}