feat: preserve and encode raw 0C record in sidecar extensions for offline analysis

minimateplus/client.py

@@ -1362,6 +1362,20 @@ def _decode_waveform_record_into(data: bytes, event: Event) -> None:
 
     Modifies event in-place.
     """
+    # ── Always preserve the raw 210 bytes ─────────────────────────────────────
+    # The 0C record carries far more than just peaks + project strings:
+    # ZC Freq, Time of Peak, Peak Acceleration, Peak Displacement, Vector
+    # Sum Time, MicL Time of Peak, and the per-channel sensor self-check
+    # results (Test Freq / Ratio / Pass-Fail) all live somewhere in this
+    # 210-byte block.  Their byte offsets are not yet mapped — keeping the
+    # raw bytes lets us decode those fields offline once we have a paired
+    # (raw 0C, BW-report) sample to fit against.  Cheap to keep around
+    # (210 bytes per event).
+    try:
+        event._raw_record = bytes(data[:210])
+    except Exception:
+        pass
+
     # ── Record type + format detection ────────────────────────────────────────
     # `record_type` is the user-facing label ("Waveform" for any triggered
     # event regardless of timestamp-header layout).  `fmt` is the internal

minimateplus/event_file_io.py

@@ -15,6 +15,7 @@ declared in `event_to_sidecar_dict()`.
 
 from __future__ import annotations
 
+import base64
 import datetime
 import hashlib
 import json
@@ -135,6 +136,20 @@ def event_to_sidecar_dict(
 
     captured_at = captured_at or datetime.datetime.utcnow()
 
+    # Stash raw 0C record bytes in `extensions.raw_records` so future
+    # field-decoding work (Peak Acceleration, ZC Freq, Time of Peak,
+    # sensor self-check results, etc.) can run offline against committed
+    # sidecars without a live device.  Cheap (~280 bytes base64) and
+    # forward-compatible (older readers ignore unknown extensions keys).
+    ext_dict: dict = dict(extensions) if extensions else {}
+    raw_0c = getattr(event, "_raw_record", None)
+    if raw_0c:
+        rr = ext_dict.setdefault("raw_records", {})
+        # Don't clobber a raw_0c that callers explicitly passed in via
+        # `extensions=...` (e.g. round-trip preservation in patch_sidecar).
+        rr.setdefault("waveform_record_b64", base64.b64encode(raw_0c).decode("ascii"))
+        rr.setdefault("waveform_record_len", len(raw_0c))
+
     return {
         "schema_version": SCHEMA_VERSION,
         "kind":           SIDECAR_KIND,
@@ -174,7 +189,7 @@ def event_to_sidecar_dict(
             "notes":         "",
         },
 
-        "extensions": extensions or {},
+        "extensions": ext_dict,
     }