fix(reboot): reject unknown uptime as fresh boot

scripts/reboot-recovery/reboot-event-detector.py

@@ -45,6 +45,13 @@ def int_value(value: Any, default: int = -1) -> int:
         return default
 
 
+def known_boot_id(value: Any) -> str:
+    boot_id = str(value or "")
+    if boot_id in {"", "unknown", "reachable_unknown_boot"}:
+        return ""
+    return boot_id
+
+
 def parse_host_probe(text: str) -> list[dict[str, Any]]:
     rows: list[dict[str, Any]] = []
     for raw_line in text.splitlines():
@@ -114,19 +121,22 @@ def build_payload(args: argparse.Namespace) -> dict[str, Any]:
         if not current["reachable"]:
             unreachable_hosts.append(alias)
         previous_boot_id = (
-            str(previous_host.get("boot_id"))
-            if isinstance(previous_host, dict) and previous_host.get("boot_id")
+            known_boot_id(previous_host.get("boot_id"))
+            if isinstance(previous_host, dict)
             else ""
         )
-        current_boot_id = str(current.get("boot_id") or "")
+        current_boot_id = known_boot_id(current.get("boot_id"))
         boot_id_changed = bool(
             previous_boot_id
-            and previous_boot_id != "unknown"
             and current_boot_id
-            and current_boot_id != "unknown"
             and previous_boot_id != current_boot_id
         )
-        fresh_boot = bool(current.get("reachable") and int_value(current.get("uptime_seconds")) <= target_seconds)
+        uptime_seconds = int_value(current.get("uptime_seconds"))
+        fresh_boot = bool(
+            current.get("reachable")
+            and uptime_seconds >= 0
+            and uptime_seconds <= target_seconds
+        )
         if boot_id_changed:
             changed_boot_id_hosts.append(alias)
         if fresh_boot:
@@ -142,7 +152,7 @@ def build_payload(args: argparse.Namespace) -> dict[str, Any]:
                     "uptime_seconds": current.get("uptime_seconds"),
                     "deadline_at": (
                         observed_at
-                        + timedelta(seconds=max(0, target_seconds - int_value(current.get("uptime_seconds"), 0)))
+                        + timedelta(seconds=max(0, target_seconds - uptime_seconds))
                     ).isoformat(timespec="seconds"),
                 }
             )

scripts/reboot-recovery/tests/test_reboot_event_detector.py

@@ -110,3 +110,63 @@ def test_reboot_detector_fails_visible_when_windows_or_vm_host_missing(tmp_path:
     assert "99" in payload["missing_hosts"]
     assert payload["all_required_hosts_observed"] is False
     assert payload["all_required_hosts_in_reboot_window"] is False
+
+
+def test_reboot_detector_does_not_treat_unknown_uptime_as_fresh_boot(
+    tmp_path: Path,
+) -> None:
+    probe_path = tmp_path / "host-probe.txt"
+    state_path = tmp_path / "state.json"
+    output_path = tmp_path / "event.json"
+    probe_path.write_text(
+        "\n".join(
+            [
+                "AWOOOI_REBOOT_AUTO_RECOVERY_HOST_PROBE=1",
+                "TARGET_HOSTS=99",
+                (
+                    "HOST_BOOT alias=99 target=192.168.0.99 "
+                    "startup_unit=vmware-host-autostart reachable=1 "
+                    "boot_id=reachable_unknown_boot uptime_seconds=unknown "
+                    "systemd_state=ping_reachable startup_enabled=unknown "
+                    "startup_active=unknown"
+                ),
+            ]
+        )
+        + "\n",
+        encoding="utf-8",
+    )
+    state_path.write_text(
+        json.dumps({"hosts": {"99": {"boot_id": "win-boot-1"}}}),
+        encoding="utf-8",
+    )
+
+    subprocess.run(
+        [
+            sys.executable,
+            str(SCRIPT),
+            "--host-probe-file",
+            str(probe_path),
+            "--state-file",
+            str(state_path),
+            "--target-minutes",
+            "10",
+            "--generated-at",
+            "2026-06-30T18:00:00+08:00",
+            "--output",
+            str(output_path),
+            "--required-host",
+            "99",
+            "--no-write-state",
+        ],
+        check=True,
+    )
+
+    payload = json.loads(output_path.read_text(encoding="utf-8"))
+
+    assert payload["observed_hosts"] == ["99"]
+    assert payload["reboot_detected"] is False
+    assert payload["fresh_boot_hosts"] == []
+    assert payload["rebooted_hosts"] == []
+    assert payload["all_required_hosts_observed"] is True
+    assert payload["all_required_hosts_in_reboot_window"] is False
+    assert payload["state_written"] is False