fix: guard disabled immersion retention windows

backlog/tasks/task-244 - Assess-and-address-PR-36-latest-CodeRabbit-review-round-2.md

@@ -0,0 +1,28 @@
+---
+id: TASK-244
+title: 'Assess and address PR #36 latest CodeRabbit review round 2'
+status: In Progress
+assignee: []
+created_date: '2026-03-29 08:09'
+labels:
+  - code-review
+  - pr-36
+dependencies: []
+references:
+  - 'https://github.com/ksyasuda/SubMiner/pull/36'
+priority: high
+ordinal: 3610
+---
+
+## Description
+
+<!-- SECTION:DESCRIPTION:BEGIN -->
+Inspect the newest CodeRabbit review round on PR #36, verify the actionable comment against the current branch, implement the confirmed fix, and verify the touched path.
+<!-- SECTION:DESCRIPTION:END -->
+
+## Acceptance Criteria
+<!-- AC:BEGIN -->
+- [ ] #1 The actionable review comment is implemented or explicitly deferred with rationale.
+- [ ] #2 Touched path is verified with the smallest sufficient test lane.
+- [ ] #3 Current PR feedback is reduced to resolved or intentionally deferred suggestions.
+<!-- AC:END -->

src/core/services/immersion-tracker/maintenance.test.ts

@@ -82,6 +82,65 @@ test('pruneRawRetention uses session retention separately from telemetry retenti
   }
 });
 
+test('pruneRawRetention skips disabled retention windows', () => {
+  const dbPath = makeDbPath();
+  const db = new Database(dbPath);
+
+  try {
+    ensureSchema(db);
+    const nowMs = 1_000_000_000;
+
+    db.exec(`
+      INSERT INTO imm_videos (
+        video_id, video_key, canonical_title, source_type, duration_ms, CREATED_DATE, LAST_UPDATE_DATE
+      ) VALUES (
+        1, 'local:/tmp/video.mkv', 'Video', 1, 0, ${nowMs}, ${nowMs}
+      );
+      INSERT INTO imm_sessions (
+        session_id, session_uuid, video_id, started_at_ms, ended_at_ms, status, CREATED_DATE, LAST_UPDATE_DATE
+      ) VALUES (
+        1, 'session-1', 1, ${nowMs - 1_000}, ${nowMs - 500}, 2, ${nowMs}, ${nowMs}
+      );
+      INSERT INTO imm_session_telemetry (
+        session_id, sample_ms, total_watched_ms, active_watched_ms, CREATED_DATE, LAST_UPDATE_DATE
+      ) VALUES (
+        1, ${nowMs - 2_000}, 0, 0, ${nowMs}, ${nowMs}
+      );
+      INSERT INTO imm_session_events (
+        session_id, event_type, ts_ms, payload_json, CREATED_DATE, LAST_UPDATE_DATE
+      ) VALUES (
+        1, 1, ${nowMs - 3_000}, '{}', ${nowMs}, ${nowMs}
+      );
+    `);
+
+    const result = pruneRawRetention(db, nowMs, {
+      eventsRetentionMs: Number.POSITIVE_INFINITY,
+      telemetryRetentionMs: Number.POSITIVE_INFINITY,
+      sessionsRetentionMs: Number.POSITIVE_INFINITY,
+    });
+
+    const remainingSessionEvents = db
+      .prepare('SELECT COUNT(*) AS count FROM imm_session_events')
+      .get() as { count: number };
+    const remainingTelemetry = db
+      .prepare('SELECT COUNT(*) AS count FROM imm_session_telemetry')
+      .get() as { count: number };
+    const remainingSessions = db
+      .prepare('SELECT COUNT(*) AS count FROM imm_sessions')
+      .get() as { count: number };
+
+    assert.equal(result.deletedSessionEvents, 0);
+    assert.equal(result.deletedTelemetryRows, 0);
+    assert.equal(result.deletedEndedSessions, 0);
+    assert.equal(remainingSessionEvents.count, 1);
+    assert.equal(remainingTelemetry.count, 1);
+    assert.equal(remainingSessions.count, 1);
+  } finally {
+    db.close();
+    cleanupDbPath(dbPath);
+  }
+});
+
 test('toMonthKey floors negative timestamps into the prior UTC month', () => {
   assert.equal(toMonthKey(-1), 196912);
   assert.equal(toMonthKey(-86_400_000), 196912);

src/core/services/immersion-tracker/maintenance.ts

@@ -53,25 +53,27 @@ export function pruneRawRetention(
     sessionsRetentionMs: number;
   },
 ): RawRetentionResult {
-  const eventCutoff = currentMs - policy.eventsRetentionMs;
-  const telemetryCutoff = currentMs - policy.telemetryRetentionMs;
-  const sessionsCutoff = currentMs - policy.sessionsRetentionMs;
-
-  const deletedSessionEvents = (
-    db.prepare(`DELETE FROM imm_session_events WHERE ts_ms < ?`).run(toDbMs(eventCutoff)) as {
-      changes: number;
-    }
-  ).changes;
-  const deletedTelemetryRows = (
-    db
-      .prepare(`DELETE FROM imm_session_telemetry WHERE sample_ms < ?`)
-      .run(toDbMs(telemetryCutoff)) as { changes: number }
-  ).changes;
-  const deletedEndedSessions = (
-    db
-      .prepare(`DELETE FROM imm_sessions WHERE ended_at_ms IS NOT NULL AND ended_at_ms < ?`)
-      .run(toDbMs(sessionsCutoff)) as { changes: number }
-  ).changes;
+  const deletedSessionEvents = Number.isFinite(policy.eventsRetentionMs)
+    ? (
+        db.prepare(`DELETE FROM imm_session_events WHERE ts_ms < ?`).run(
+          toDbMs(currentMs - policy.eventsRetentionMs),
+        ) as { changes: number }
+      ).changes
+    : 0;
+  const deletedTelemetryRows = Number.isFinite(policy.telemetryRetentionMs)
+    ? (
+        db
+          .prepare(`DELETE FROM imm_session_telemetry WHERE sample_ms < ?`)
+          .run(toDbMs(currentMs - policy.telemetryRetentionMs)) as { changes: number }
+      ).changes
+    : 0;
+  const deletedEndedSessions = Number.isFinite(policy.sessionsRetentionMs)
+    ? (
+        db
+          .prepare(`DELETE FROM imm_sessions WHERE ended_at_ms IS NOT NULL AND ended_at_ms < ?`)
+          .run(toDbMs(currentMs - policy.sessionsRetentionMs)) as { changes: number }
+      ).changes
+    : 0;
 
   return {
     deletedSessionEvents,