CHANGELOG.md

@@ -6,6 +6,19 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ---
 
+## [1.5.2] - 2026-05-10
+
+### Added
+- **`SFM_MAX_FORWARDS_PER_PASS` rate cap.**  Default 500 events per scan tick (60-second interval = ~30K events/hour).  Drips first-deploy backfill instead of hammering the SFM server with one giant burst on machines that have hundreds of thousands of historical events in the BW ACH folder.  `0` = unlimited (preserves the 1.5.0 behaviour for ops who want it).
+- **`event_forwarder.py --seed-state` CLI mode.**  Walks the watch folder once, sha256s every in-window event, and marks them all as already-forwarded *without* POSTing anything.  The recommended pre-deploy workflow on machines with a large historical archive — flip `SFM_FORWARD_ENABLED=true` after seeding and only events that appear *from then on* get forwarded.
+- New "Max Events Per Pass" spinbox in the Settings dialog's SFM Forward tab.
+- README "First-time deployment" section documenting both options.
+- 7 new unit tests covering the cap (oldest-first ordering, cap=0 unlimited, cap=N enforcement) and the seed-state mode (skips out-of-window files, idempotent across re-runs, end-to-end skip-after-seed).
+
+### Behaviour change
+
+The scan loop now sorts entries by mtime ascending before walking, so backfill always advances chronologically (oldest qualifying event first).  Without the cap the visible behaviour is identical; with the cap it means each scan reliably advances and we never get stuck re-considering the same N newest files.
+
 ## [1.5.1] - 2026-05-10
 
 ### Added

README.md

@@ -1,4 +1,4 @@
-# Series 3 Watcher v1.5.1
+# Series 3 Watcher v1.5.2
 
 Monitors Instantel **Series 3 (Minimate)** call-in activity on a Blastware server. Runs as a **system tray app** that starts automatically on login, reports heartbeats to terra-view, and self-updates from Gitea.
 
@@ -88,7 +88,7 @@ All settings live in `config.ini`. The Setup Wizard covers every field, but here
 | `UPDATE_SOURCE` | `gitea` (default) or `url` — where to check for updates |
 | `UPDATE_URL` | Base URL of the update server when `UPDATE_SOURCE = url` (e.g. terra-view URL). The watcher fetches `/api/updates/series3-watcher/version.txt` and `/api/updates/series3-watcher/series3-watcher.exe` from this base. |
 
-### SFM Event Forwarder (v1.5.1+)
+### SFM Event Forwarder (v1.5.2+)
 
 Forwards each Blastware event binary (and its paired `<binary>.TXT` ASCII report when present) to an SFM server's `/db/import/blastware_file` endpoint, where the report is parsed and the rich per-channel stats (PPV, ZC Freq, Time of Peak, Peak Acceleration / Displacement, sensor self-check) land in a searchable database. **Default-off** — existing deployments keep their old behaviour after auto-updating until the operator opts in.
 
@@ -101,9 +101,27 @@ Forwards each Blastware event binary (and its paired `<binary>.TXT` ASCII report
 | `SFM_MISSING_REPORT_GRACE_SECONDS` | If a `.TXT` partner hasn't appeared after this many seconds, forward the binary alone (default `60`) |
 | `SFM_HTTP_TIMEOUT` | Per-request HTTP timeout in seconds (default `60`) |
 | `SFM_STATE_FILE` | Path to the JSON state file tracking sha256 of forwarded events. Leave blank to default to `<log dir>/sfm_forwarded.json` |
+| `SFM_MAX_FORWARDS_PER_PASS` | Max events forwarded per scan tick (default `500`, `0` = unlimited). Drip-feeds backfill so a folder with thousands of qualifying events doesn't hammer the SFM server in one giant burst. |
 
 Forwarded files are tracked by sha256 in the state file, so re-scans / restarts / auto-updates never re-POST the same content. A failed POST stays in the pending pool and is retried on the next interval.
 
+#### First-time deployment on a folder with a large historical archive
+
+If you're enabling SFM forwarding on a Blastware ACH machine that's been accumulating events for years (tens or hundreds of thousands of files in the watch folder), you almost certainly **don't** want the watcher to forward all of them on first run. Two options:
+
+1. **Skip the historical backfill (recommended).** Run the seed-state CLI once before flipping `SFM_FORWARD_ENABLED=true`. It walks the folder, sha256s every existing in-window event, and marks them all as already-forwarded — without POSTing anything. The watcher then only forwards events that appear *after* the seed run.
+
+   ```
+   python event_forwarder.py --seed-state ^
+       --watch "C:\Blastware 10\Event\autocall home" ^
+       --state "C:\Users\<you>\AppData\Local\Series3Watcher\agent_logs\sfm_forwarded.json" ^
+       --max-age-days 365
+   ```
+
+2. **Throttle the backfill.** Leave `SFM_MAX_FORWARDS_PER_PASS` at its 500 default and let the watcher drip-feed. With a 60-second `SFM_FORWARD_INTERVAL_SECONDS` that's ~30K events/hour throughput. Backfill of 30K events takes about an hour, 100K takes ~3.5 hours. The cap fires per scan, so heartbeat and forwarding share the watcher's main loop without saturating it.
+
+Combine both for a fully controlled rollout: seed-state to skip the deep archive, then leave the cap on as a steady-state safety net.
+
 ---
 
 ## Tray Icon
@@ -137,7 +155,7 @@ To view connected watchers: **Settings → Developer → Watcher Manager**.
 
 ## Versioning
 
-Follows **Semantic Versioning**. Current release: **v1.5.1**.
+Follows **Semantic Versioning**. Current release: **v1.5.2**.
 See `CHANGELOG.md` for full history.
 
 ---

config-template.ini

@@ -63,3 +63,12 @@ SFM_HTTP_TIMEOUT = 60
 # to default to <log dir>/sfm_forwarded.json.
 SFM_STATE_FILE =
 
+# Per-pass cap — forward at most N events per scan tick.  0 = unlimited.
+# Default 500 throttles first-deploy backfill on machines with large
+# historical archives (tens or hundreds of thousands of events) so
+# the SFM server isn't hammered with one giant burst.  At 60s scan
+# interval × 500 events/pass that's 30K events/hour throughput.
+# See README "First-time deployment" for the recommended
+# `--seed-state` workflow that skips the historical backfill entirely.
+SFM_MAX_FORWARDS_PER_PASS = 500
+

event_forwarder.py

@@ -209,6 +209,7 @@ def find_pending_events(
     max_age_days: int,
     quiescence_seconds: float = DEFAULT_QUIESCENCE_SECONDS,
     missing_report_grace_seconds: float = DEFAULT_MISSING_REPORT_GRACE_SECONDS,
+    max_per_pass: int = 0,
 ) -> List[Tuple[str, Optional[str]]]:
     """
     Walk `watch_dir` and return the list of (binary_path, txt_path_or_None)
@@ -226,6 +227,11 @@ def find_pending_events(
         missing_report_grace_seconds, we forward without the TXT.
         Younger binaries with a missing TXT are deferred — let BW
         finish writing the report.
+      - When `max_per_pass > 0`, return at most that many pairs.
+        Older files (lower mtime) are forwarded first so backfill
+        proceeds chronologically.  Use this to drip-feed a folder
+        with thousands of qualifying events instead of hammering
+        the SFM server with one giant burst.
     """
     if not os.path.isdir(watch_dir):
         log.warning("forward scan: watch dir not found: %s", watch_dir)
@@ -248,6 +254,20 @@ def find_pending_events(
     # Cache existence of TXT partners so we don't stat() each twice.
     names = {e.name for e in entries if e.is_file()}
 
+    # Sort by mtime ASCENDING so chronological backfill happens oldest-first.
+    # When max_per_pass clamps the list, we always advance — we don't get
+    # stuck re-considering the same N newest files every scan.
+    def _mtime(entry: os.DirEntry) -> float:
+        try:
+            return entry.stat().st_mtime
+        except OSError:
+            return 0.0
+
+    entries = sorted(
+        (e for e in entries if e.is_file()),
+        key=_mtime,
+    )
+
     for e in entries:
         if not e.is_file():
             continue
@@ -302,9 +322,13 @@ def find_pending_events(
         # Stash size + digest on the tuple-replacement for use during forward;
         # callers can re-derive but caching avoids a second sha256.
 
+        # Per-pass cap: once we have enough pending, stop scanning.
+        if max_per_pass and len(pending) >= max_per_pass:
+            break
+
     log.debug(
-        "forward scan: %d pending  skipped_inflight=%d  already_forwarded=%d",
+        "forward scan: %d pending  skipped_inflight=%d  already_forwarded=%d  cap=%d",
-        len(pending), skipped_inflight, skipped_already_forwarded,
+        len(pending), skipped_inflight, skipped_already_forwarded, max_per_pass,
     )
     return pending
 
@@ -442,6 +466,7 @@ def forward_pending(
     quiescence_seconds: float = DEFAULT_QUIESCENCE_SECONDS,
     missing_report_grace_seconds: float = DEFAULT_MISSING_REPORT_GRACE_SECONDS,
     timeout: float = DEFAULT_HTTP_TIMEOUT,
+    max_per_pass: int = 0,
     logger: Optional[Any] = None,
 ) -> Dict[str, int]:
     """
@@ -467,6 +492,7 @@ def forward_pending(
         max_age_days=max_age_days,
         quiescence_seconds=quiescence_seconds,
         missing_report_grace_seconds=missing_report_grace_seconds,
+        max_per_pass=max_per_pass,
     )
 
     counts = {"scanned": len(pending), "forwarded": 0, "errors": 0, "with_report": 0}
@@ -502,3 +528,152 @@ def forward_pending(
             )
 
     return counts
+
+
+# ── Seed-state mode (skip historical backfill on first deploy) ────────────────
+
+
+def seed_state_from_folder(
+    watch_dir: str,
+    state: ForwardState,
+    *,
+    max_age_days: int = 365,
+    logger: Optional[Any] = None,
+) -> Dict[str, int]:
+    """Walk `watch_dir` and mark every existing event binary as already
+    forwarded — without POSTing anything.
+
+    This is the right tool for a first deploy on a machine that already
+    has tens or hundreds of thousands of historical events in the BW
+    ACH folder.  Run it ONCE before enabling SFM_FORWARD_ENABLED:
+
+        python event_forwarder.py --seed-state \
+            --watch "C:\\Blastware 10\\Event\\autocall home" \
+            --state "C:\\...\\sfm_forwarded.json" \
+            [--max-age-days 365]
+
+    The watcher then starts forwarding only events that appear AFTER
+    the seed run.  Files older than `max_age_days` are still skipped
+    by the regular scan loop — we don't bother seeding them because
+    they wouldn't be forwarded anyway.
+
+    Returns a counts dict:
+        {"scanned": int, "seeded": int, "already_known": int, "skipped_too_old": int}
+    """
+    def _log(msg: str) -> None:
+        if logger:
+            logger(msg)
+        else:
+            log.info(msg)
+
+    counts = {"scanned": 0, "seeded": 0, "already_known": 0, "skipped_too_old": 0}
+
+    if not os.path.isdir(watch_dir):
+        _log(f"[seed] watch dir not found: {watch_dir}")
+        return counts
+
+    now_ts = time.time()
+    max_age_seconds = max(1, int(max_age_days)) * 86400.0
+
+    try:
+        with os.scandir(watch_dir) as it:
+            entries = [e for e in it if e.is_file()]
+    except OSError as exc:
+        _log(f"[seed] scandir failed on {watch_dir}: {exc}")
+        return counts
+
+    for e in entries:
+        if not is_event_binary(e.path):
+            continue
+        counts["scanned"] += 1
+        try:
+            mtime = e.stat().st_mtime
+            size  = e.stat().st_size
+        except OSError:
+            continue
+        if (now_ts - mtime) > max_age_seconds:
+            counts["skipped_too_old"] += 1
+            continue
+        try:
+            digest = sha256_of_file(e.path)
+        except OSError as exc:
+            _log(f"[seed] sha256 failed for {e.path}: {exc}")
+            continue
+        if state.is_forwarded(digest):
+            counts["already_known"] += 1
+            continue
+        state.mark_forwarded(digest, e.name, size)
+        counts["seeded"] += 1
+        if counts["seeded"] % 1000 == 0:
+            _log(f"[seed] progress: {counts['seeded']} seeded so far...")
+
+    _log(
+        f"[seed] done.  scanned={counts['scanned']}  seeded={counts['seeded']}  "
+        f"already_known={counts['already_known']}  "
+        f"skipped_too_old={counts['skipped_too_old']}"
+    )
+    return counts
+
+
+# ── CLI entry point ─────────────────────────────────────────────────────────
+
+
+def _main() -> int:
+    """Command-line interface for one-shot operations.
+
+    Currently supports a single mode:
+
+        python event_forwarder.py --seed-state \
+            --watch "<path/to/BW autocall folder>" \
+            --state "<path/to/sfm_forwarded.json>" \
+            [--max-age-days 365]
+
+    which marks every existing in-window event binary as already
+    forwarded (without POSTing) so the watcher only forwards events
+    appearing AFTER the seed.
+    """
+    import argparse
+    parser = argparse.ArgumentParser(
+        description="Series 3 Watcher — SFM event forwarder utilities",
+    )
+    parser.add_argument(
+        "--seed-state", action="store_true",
+        help="Mark every event binary in --watch as already-forwarded "
+             "(without POSTing).  Use this BEFORE enabling SFM_FORWARD "
+             "on a machine with a large historical archive.",
+    )
+    parser.add_argument(
+        "--watch", required=True,
+        help="Path to the Blastware ACH folder.",
+    )
+    parser.add_argument(
+        "--state", required=True,
+        help="Path to the JSON state file.  Will be created if missing.",
+    )
+    parser.add_argument(
+        "--max-age-days", type=int, default=365,
+        help="Only seed files newer than this many days (default 365).",
+    )
+    args = parser.parse_args()
+
+    if not args.seed_state:
+        parser.error("specify --seed-state (no other modes supported yet)")
+
+    print(f"[seed] watch_dir = {args.watch}")
+    print(f"[seed] state     = {args.state}")
+    print(f"[seed] max_age   = {args.max_age_days} days")
+
+    state = ForwardState(args.state)
+    print(f"[seed] state currently has {state.count()} entries")
+    seed_state_from_folder(
+        args.watch, state,
+        max_age_days=args.max_age_days,
+        logger=lambda m: print(m),
+    )
+    print(f"[seed] state now has {state.count()} entries")
+    return 0
+
+
+if __name__ == "__main__":
+    import sys
+    sys.exit(_main())

installer.iss

@@ -3,7 +3,7 @@
 
 [Setup]
 AppName=Series 3 Watcher
-AppVersion=1.5.1
+AppVersion=1.5.2
 AppPublisher=Terra-Mechanics Inc.
 DefaultDirName={pf}\Series3Watcher
 DefaultGroupName=Series 3 Watcher

series3_tray.py

@@ -1,5 +1,5 @@
 """
-Series 3 Watcher — System Tray Launcher  v1.5.1
+Series 3 Watcher — System Tray Launcher  v1.5.2
 Requires: pystray, Pillow, tkinter (stdlib)
 
 Run with:  pythonw series3_tray.py   (no console window)

series3_watcher.py

@@ -104,6 +104,12 @@ def load_config(path: str) -> Dict[str, Any]:
         # State file for forwarded-sha256 idempotency tracking.
         # Defaults next to the log file for easy operator access.
         "SFM_STATE_FILE":              get_str("SFM_STATE_FILE", ""),
+        # Per-pass cap — forward at most N events per scan tick.
+        # 0 = unlimited.  Default 500 as a safety against accidentally
+        # backfilling tens of thousands of events in one burst on
+        # first deploy in a folder that's been accumulating for years.
+        # See README "First-time deployment" section.
+        "SFM_MAX_FORWARDS_PER_PASS":   get_int("SFM_MAX_FORWARDS_PER_PASS", 500),
     }
 
 
@@ -241,7 +247,7 @@ def scan_latest(
 
 
 # --- API heartbeat / SFM telemetry helpers ---
-VERSION = "1.5.1"
+VERSION = "1.5.2"
 
 
 def _read_log_tail(log_file: str, n: int = 25) -> Optional[list]:
@@ -522,6 +528,7 @@ def run_watcher(state: Dict[str, Any], stop_event: threading.Event) -> None:
                                 cfg.get("SFM_MISSING_REPORT_GRACE_SECONDS", 60)
                             ),
                             timeout=int(cfg.get("SFM_HTTP_TIMEOUT", 60)),
+                            max_per_pass=int(cfg.get("SFM_MAX_FORWARDS_PER_PASS", 500)),
                             logger=lambda m: log_message(LOG_FILE, ENABLE_LOGGING, m),
                         )
                         last_forward_ts = now_ts

settings_dialog.py

@@ -1,5 +1,5 @@
 """
-Series 3 Watcher — Settings Dialog  v1.5.1
+Series 3 Watcher — Settings Dialog  v1.5.2
 
 Provides a Tkinter settings dialog that doubles as a first-run wizard.
 
@@ -52,6 +52,7 @@ DEFAULTS = {
     "SFM_MISSING_REPORT_GRACE_SECONDS": "60",
     "SFM_HTTP_TIMEOUT":                 "60",
     "SFM_STATE_FILE":                   "",
+    "SFM_MAX_FORWARDS_PER_PASS":        "500",
 }
 
 
@@ -257,6 +258,7 @@ class SettingsDialog:
         self.var_sfm_missing_report_grace    = tk.StringVar(value=v["SFM_MISSING_REPORT_GRACE_SECONDS"])
         self.var_sfm_http_timeout            = tk.StringVar(value=v["SFM_HTTP_TIMEOUT"])
         self.var_sfm_state_file              = tk.StringVar(value=v["SFM_STATE_FILE"])
+        self.var_sfm_max_per_pass            = tk.StringVar(value=v["SFM_MAX_FORWARDS_PER_PASS"])
 
     # --- UI construction ---
 
@@ -522,15 +524,16 @@ class SettingsDialog:
         self._sfm_test_status.grid(row=0, column=2, padx=(6, 0))
 
         _add_label_spinbox(f, 2, "Forward Interval (sec)",     self.var_sfm_forward_interval,     5, 3600)
-        _add_label_spinbox(f, 3, "Quiescence (sec)",           self.var_sfm_quiescence,           1,   60)
+        _add_label_spinbox(f, 3, "Max Events Per Pass",        self.var_sfm_max_per_pass,         0, 100000)
-        _add_label_spinbox(f, 4, "Missing-Report Grace (sec)", self.var_sfm_missing_report_grace, 0,  600)
+        _add_label_spinbox(f, 4, "Quiescence (sec)",           self.var_sfm_quiescence,           1,   60)
-        _add_label_spinbox(f, 5, "HTTP Timeout (sec)",         self.var_sfm_http_timeout,         5,  600)
+        _add_label_spinbox(f, 5, "Missing-Report Grace (sec)", self.var_sfm_missing_report_grace, 0,  600)
+        _add_label_spinbox(f, 6, "HTTP Timeout (sec)",         self.var_sfm_http_timeout,         5,  600)
 
         tk.Label(f, text="State File", anchor="w").grid(
-            row=6, column=0, sticky="w", padx=(8, 4), pady=4
+            row=7, column=0, sticky="w", padx=(8, 4), pady=4
         )
         state_frame = tk.Frame(f)
-        state_frame.grid(row=6, column=1, sticky="ew", padx=(0, 8), pady=4)
+        state_frame.grid(row=7, column=1, sticky="ew", padx=(0, 8), pady=4)
         state_frame.columnconfigure(0, weight=1)
 
         state_entry = ttk.Entry(state_frame, textvariable=self.var_sfm_state_file, width=32)
@@ -560,7 +563,7 @@ class SettingsDialog:
             "to default to <log dir>/sfm_forwarded.json."
         )
         tk.Label(f, text=hint_text, justify="left", fg="#555555", wraplength=380).grid(
-            row=7, column=0, columnspan=2, sticky="w", padx=(8, 8), pady=(8, 4)
+            row=8, column=0, columnspan=2, sticky="w", padx=(8, 8), pady=(8, 4)
         )
 
     def _test_sfm_connection(self):
@@ -637,6 +640,7 @@ class SettingsDialog:
             (self.var_sfm_quiescence,              "SFM Quiescence",                1,   60,   5),
             (self.var_sfm_missing_report_grace,    "SFM Missing-Report Grace",      0,  600,  60),
             (self.var_sfm_http_timeout,            "SFM HTTP Timeout",              5,  600,  60),
+            (self.var_sfm_max_per_pass,            "SFM Max Events Per Pass",       0, 100000, 500),
         ]
         int_values = {}
         for var, name, mn, mx, dflt in checks:
@@ -693,6 +697,7 @@ class SettingsDialog:
             "SFM_MISSING_REPORT_GRACE_SECONDS": str(int_values["SFM Missing-Report Grace"]),
             "SFM_HTTP_TIMEOUT":                 str(int_values["SFM HTTP Timeout"]),
             "SFM_STATE_FILE":                   self.var_sfm_state_file.get().strip(),
+            "SFM_MAX_FORWARDS_PER_PASS":        str(int_values["SFM Max Events Per Pass"]),
         }
 
         try:

test_event_forwarder.py

@@ -223,6 +223,154 @@ class TestFindPendingEvents(unittest.TestCase):
             )
             self.assertEqual(len(pending), 0)
 
+    def test_max_per_pass_caps_returned_count(self):
+        """When max_per_pass is set, return at most that many pairs."""
+        with tempfile.TemporaryDirectory() as tmp:
+            tmp_p = Path(tmp)
+            # Create 5 distinct event binaries with paired .TXTs
+            for i, name in enumerate(
+                ["M529LK01.AB0", "M529LK02.AB0", "M529LK03.AB0",
+                 "M529LK04.AB0", "M529LK05.AB0"],
+            ):
+                self._make(tmp_p, name, age_seconds=120 + i,
+                           content=("bin-" + str(i)).encode())
+                self._make(tmp_p, name + ".TXT", age_seconds=110 + i,
+                           content=b"report")
+
+            state = ef.ForwardState(str(tmp_p / "fwd.json"))
+            pending = ef.find_pending_events(
+                str(tmp_p), state,
+                max_age_days=30,
+                quiescence_seconds=5,
+                missing_report_grace_seconds=60,
+                max_per_pass=2,
+            )
+            self.assertEqual(len(pending), 2)
+
+    def test_max_per_pass_zero_means_unlimited(self):
+        with tempfile.TemporaryDirectory() as tmp:
+            tmp_p = Path(tmp)
+            for i in range(4):
+                self._make(tmp_p, "M529LK0{}.AB0".format(i),
+                           age_seconds=120 + i,
+                           content=("bin-" + str(i)).encode())
+            state = ef.ForwardState(str(tmp_p / "fwd.json"))
+            pending = ef.find_pending_events(
+                str(tmp_p), state,
+                max_age_days=30,
+                quiescence_seconds=5,
+                missing_report_grace_seconds=60,
+                max_per_pass=0,
+            )
+            self.assertEqual(len(pending), 4)
+
+    def test_max_per_pass_returns_oldest_first(self):
+        """Backfill should advance chronologically — oldest qualifying
+        files first.  This way successive scans always make progress
+        instead of getting stuck re-considering the same N newest files."""
+        with tempfile.TemporaryDirectory() as tmp:
+            tmp_p = Path(tmp)
+            # ages: 200s (oldest), 150s, 100s, 50s (skipped — within grace)
+            ages = [200, 150, 100, 50]
+            for i, age in enumerate(ages):
+                self._make(tmp_p, "M529LK0{}.AB0".format(i),
+                           age_seconds=age, content=("c" + str(i)).encode())
+                self._make(tmp_p, "M529LK0{}.AB0.TXT".format(i),
+                           age_seconds=age - 10, content=b"r")
+
+            state = ef.ForwardState(str(tmp_p / "fwd.json"))
+            pending = ef.find_pending_events(
+                str(tmp_p), state,
+                max_age_days=30, quiescence_seconds=5,
+                missing_report_grace_seconds=60, max_per_pass=2,
+            )
+            # Oldest two should be M529LK00 (200s) and M529LK01 (150s)
+            names = [os.path.basename(p[0]) for p in pending]
+            self.assertEqual(names, ["M529LK00.AB0", "M529LK01.AB0"])
+
+
+# ── Seed-state mode ──────────────────────────────────────────────────────────
+
+
+class TestSeedStateFromFolder(unittest.TestCase):
+
+    def _make(self, dir_path: Path, name: str, age_seconds: float = 100,
+              content: bytes = b"x") -> Path:
+        p = dir_path / name
+        p.write_bytes(content)
+        target = time.time() - age_seconds
+        os.utime(p, (target, target))
+        return p
+
+    def test_seeds_every_in_window_event_without_posting(self):
+        with tempfile.TemporaryDirectory() as tmp:
+            tmp_p = Path(tmp)
+            for i in range(3):
+                self._make(tmp_p, "M529LK0{}.AB0".format(i),
+                           age_seconds=120 + i, content=("e" + str(i)).encode())
+            # Plus a non-event file we should ignore
+            self._make(tmp_p, "BE11529.MLG", age_seconds=120, content=b"mlg")
+
+            state = ef.ForwardState(str(tmp_p / "seed.json"))
+            counts = ef.seed_state_from_folder(
+                str(tmp_p), state, max_age_days=30,
+            )
+            self.assertEqual(counts["scanned"], 3)
+            self.assertEqual(counts["seeded"], 3)
+            self.assertEqual(counts["already_known"], 0)
+            self.assertEqual(state.count(), 3)
+
+    def test_seed_skips_files_beyond_max_age_days(self):
+        with tempfile.TemporaryDirectory() as tmp:
+            tmp_p = Path(tmp)
+            self._make(tmp_p, "M529LK01.AB0", age_seconds=120, content=b"new")
+            self._make(tmp_p, "M529LK02.AB0", age_seconds=10 * 86400,
+                       content=b"in-window")    # 10d < 30d cutoff
+            self._make(tmp_p, "M529LK03.AB0", age_seconds=400 * 86400,
+                       content=b"way-old")      # 400d > 30d cutoff
+
+            state = ef.ForwardState(str(tmp_p / "seed.json"))
+            counts = ef.seed_state_from_folder(
+                str(tmp_p), state, max_age_days=30,
+            )
+            self.assertEqual(counts["seeded"], 2)
+            self.assertEqual(counts["skipped_too_old"], 1)
+
+    def test_seeded_files_are_then_skipped_by_normal_scan(self):
+        """End-to-end: seed once, then a normal scan should produce
+        zero pending events for the seeded files."""
+        with tempfile.TemporaryDirectory() as tmp:
+            tmp_p = Path(tmp)
+            self._make(tmp_p, "M529LK01.AB0", age_seconds=120, content=b"x")
+            self._make(tmp_p, "M529LK01.AB0.TXT", age_seconds=110, content=b"r")
+            self._make(tmp_p, "M529LK02.AB0", age_seconds=120, content=b"y")
+            self._make(tmp_p, "M529LK02.AB0.TXT", age_seconds=110, content=b"r")
+
+            state = ef.ForwardState(str(tmp_p / "seed.json"))
+            ef.seed_state_from_folder(str(tmp_p), state, max_age_days=30)
+
+            pending = ef.find_pending_events(
+                str(tmp_p), state,
+                max_age_days=30, quiescence_seconds=5,
+                missing_report_grace_seconds=60,
+            )
+            self.assertEqual(len(pending), 0,
+                             "seed should have marked everything already-forwarded")
+
+    def test_seed_is_idempotent(self):
+        """Re-running seed twice doesn't duplicate entries or POST anything."""
+        with tempfile.TemporaryDirectory() as tmp:
+            tmp_p = Path(tmp)
+            self._make(tmp_p, "M529LK01.AB0", age_seconds=120, content=b"x")
+
+            state = ef.ForwardState(str(tmp_p / "seed.json"))
+            counts1 = ef.seed_state_from_folder(str(tmp_p), state, max_age_days=30)
+            counts2 = ef.seed_state_from_folder(str(tmp_p), state, max_age_days=30)
+            self.assertEqual(counts1["seeded"], 1)
+            self.assertEqual(counts2["seeded"], 0)
+            self.assertEqual(counts2["already_known"], 1)
+            self.assertEqual(state.count(), 1)
+
 
 # ── Multipart encoder ────────────────────────────────────────────────────────