backend: initial commit

bincio/extract/timeseries.py

@@ -0,0 +1,58 @@
+"""Downsample a list of DataPoints to at most 1 sample/second and build
+the BAS timeseries object (parallel arrays)."""
+
+from datetime import datetime
+from typing import Optional
+
+from bincio.extract.models import DataPoint
+
+
+def build_timeseries(
+    points: list[DataPoint],
+    started_at: datetime,
+    privacy: str = "public",
+) -> dict:
+    """Return the BAS `timeseries` object.
+
+    privacy='no_gps' or 'private' → lat/lon set to null.
+    Downsamples so at most one point per second is emitted.
+    """
+    if not points:
+        return {"t": []}
+
+    include_gps = privacy not in ("no_gps", "private")
+
+    # Downsample: keep at most one point per second
+    sampled: list[DataPoint] = []
+    last_t: Optional[int] = None
+    for p in points:
+        t = int((p.timestamp - started_at).total_seconds())
+        if t < 0:
+            continue
+        if last_t is not None and t == last_t:
+            continue  # skip sub-second duplicates
+        sampled.append(p)
+        last_t = t
+
+    ts_vals   = [int((p.timestamp - started_at).total_seconds()) for p in sampled]
+    lat_vals  = [round(p.lat, 7) if p.lat is not None else None for p in sampled] if include_gps else None
+    lon_vals  = [round(p.lon, 7) if p.lon is not None else None for p in sampled] if include_gps else None
+    ele_vals  = [round(p.elevation_m, 1) if p.elevation_m is not None else None for p in sampled]
+    spd_vals  = [round(p.speed_kmh, 2) if p.speed_kmh is not None else None for p in sampled]
+    hr_vals   = [p.hr_bpm for p in sampled]
+    cad_vals  = [p.cadence_rpm for p in sampled]
+    pwr_vals  = [p.power_w for p in sampled]
+    tmp_vals  = [round(p.temperature_c, 1) if p.temperature_c is not None else None for p in sampled]
+
+    result: dict = {
+        "t":             ts_vals,
+        "lat":           lat_vals,
+        "lon":           lon_vals,
+        "elevation_m":   ele_vals,
+        "speed_kmh":     spd_vals,
+        "hr_bpm":        hr_vals,
+        "cadence_rpm":   cad_vals,
+        "power_w":       pwr_vals,
+        "temperature_c": tmp_vals,
+    }
+    return result