backend: initial commit

bincio/extract/parsers/gpx.py

@@ -0,0 +1,82 @@
+"""GPX file parser."""
+
+from datetime import timezone
+from pathlib import Path
+
+import gpxpy
+import gpxpy.gpx
+
+from bincio.extract.models import DataPoint, ParsedActivity
+from bincio.extract.parsers.base import BaseParser
+from bincio.extract.sport import normalise_sport
+
+# Known GPX extension namespaces
+_NS_GARMIN = "http://www.garmin.com/xmlschemas/TrackPointExtension/v1"
+_NS_GARMIN_V2 = "http://www.garmin.com/xmlschemas/TrackPointExtension/v2"
+
+
+class GpxParser(BaseParser):
+    def parse(self, path: Path, raw_bytes: bytes) -> ParsedActivity:
+        gpx = gpxpy.parse(raw_bytes.decode("utf-8", errors="replace"))
+
+        points: list[DataPoint] = []
+        for track in gpx.tracks:
+            for segment in track.segments:
+                for pt in segment.points:
+                    if pt.time is None:
+                        continue
+                    ts = pt.time
+                    if ts.tzinfo is None:
+                        ts = ts.replace(tzinfo=timezone.utc)
+
+                    dp = DataPoint(
+                        timestamp=ts,
+                        lat=pt.latitude,
+                        lon=pt.longitude,
+                        elevation_m=pt.elevation,
+                    )
+                    _apply_extensions(pt, dp)
+                    points.append(dp)
+
+        if not points:
+            raise ValueError(f"No trackpoints found in {path.name}")
+
+        sport = normalise_sport(
+            (gpx.tracks[0].type if gpx.tracks else None) or "cycling"
+        )
+        started_at = points[0].timestamp
+
+        return ParsedActivity(
+            points=points,
+            sport=sport,
+            started_at=started_at,
+            source_file=path.name,
+            source_hash="",  # set by factory
+        )
+
+
+def _apply_extensions(pt: gpxpy.gpx.GPXTrackPoint, dp: DataPoint) -> None:
+    """Extract HR, cadence, temperature from Garmin TrackPointExtension."""
+    if pt.extensions is None:
+        return
+    for ext in pt.extensions:
+        ns = _strip_ns(ext.tag)
+        if ns == "TrackPointExtension":
+            for child in ext:
+                tag = _strip_ns(child.tag)
+                val = child.text
+                if val is None:
+                    continue
+                if tag == "hr":
+                    dp.hr_bpm = int(float(val))
+                elif tag == "cad":
+                    dp.cadence_rpm = int(float(val))
+                elif tag == "atemp":
+                    dp.temperature_c = float(val)
+                elif tag == "speed":
+                    dp.speed_kmh = float(val) * 3.6  # m/s → km/h
+
+
+def _strip_ns(tag: str) -> str:
+    """'{namespace}localname' → 'localname'."""
+    return tag.split("}")[-1] if "}" in tag else tag