Function submit_position

backend/app/main.py:466–529

(
    challenge_id: str,
    payload: PositionIn,
    response: Response,
    participant=Cookie(default=None, alias=COOKIE_NAME),
)

@app.post("/api/challenges/{challenge_id}/position")
def submit_position(
    challenge_id: str,
    payload: PositionIn,
    response: Response,
    participant=Cookie(default=None, alias=COOKIE_NAME),
) -> dict:
    current = get_or_create_participant(response, participant)
    with connect() as conn:
        challenge = conn.execute(
            "SELECT * FROM challenges WHERE id = ? AND status = 'active'",
            (challenge_id,),
        ).fetchone()
        if not challenge:
            raise HTTPException(status_code=404, detail="Active challenge not found")

        if payload.accuracy_m is not None and payload.accuracy_m > MAX_ACCURACY_M:
            record_event(conn, challenge_id, current["id"], "low_accuracy", payload)
            return {"accepted": False, "reason": "low_accuracy"}
        if payload.speed_mps is not None and payload.speed_mps > MAX_SPEED_MPS:
            record_event(conn, challenge_id, current["id"], "too_fast", payload)
            return {"accepted": False, "reason": "too_fast"}

        map_lat, map_lng = wgs84_to_gcj02(payload.lat, payload.lng)
        cell_id = latlng_to_cell(map_lat, map_lng, int(challenge["h3_resolution"]))
        exists = conn.execute(
            """
            SELECT 1 FROM challenge_cells
            WHERE challenge_id = ? AND cell_id = ?
            """,
            (challenge_id, cell_id),
        ).fetchone()
        if not exists:
            record_event(conn, challenge_id, current["id"], "outside_area", payload)
            return {
                "accepted": False,
                "reason": "outside_area",
                "cell_id": cell_id,
                "map_lat": map_lat,
                "map_lng": map_lng,
            }

        cur = conn.execute(
            """
            INSERT OR IGNORE INTO user_unlocked_cells
              (challenge_id, participant_id, cell_id, source, accuracy_m, speed_mps, created_at)
            VALUES (?, ?, ?, 'gps', ?, ?, ?)
            """,
            (
                challenge_id,
                current["id"],
                cell_id,
                payload.accuracy_m,
                payload.speed_mps,
                now_iso(),
            ),
        )
        return {
            "accepted": True,