Spaces:
Sleeping
Sleeping
| """Multi-source verification scoring. | |
| An alert's `verified_score` (0-100) combines independent signals: | |
| • witnesses — distinct users who say they also see the incident | |
| • corroboration — other alerts of the same category posted nearby recently | |
| • weather_match — external weather data consistent with the alert category | |
| """ | |
| from __future__ import annotations | |
| from datetime import datetime, timedelta, timezone | |
| from bson import ObjectId | |
| CORROBORATE_RADIUS_M = 500 | |
| CORROBORATE_WINDOW_MIN = 30 | |
| WITNESS_RADIUS_M = 2000 # users within 2 km can add a witness vote | |
| def compute_verified_score( | |
| witnesses: int, | |
| corroborating_alerts: int, | |
| weather_match: bool, | |
| ) -> int: | |
| """Composite 0-100 score. Each independent source adds capped weight.""" | |
| score = 0 | |
| score += min(40, witnesses * 8) # up to 40 pts from community witnesses | |
| score += min(40, corroborating_alerts * 15) # up to 40 pts from nearby same-category alerts | |
| if weather_match: | |
| score += 20 # 20 pts from external weather confirmation | |
| return min(100, score) | |
| async def find_corroborating_alerts(db, category: str, coordinates: list[float]): | |
| """Return open alerts of the same category within the corroboration | |
| radius/window — excluding resolved ones. Caller filters out the alert | |
| being scored if needed.""" | |
| since = datetime.now(timezone.utc) - timedelta(minutes=CORROBORATE_WINDOW_MIN) | |
| cursor = db.alerts.find( | |
| { | |
| "category": category, | |
| "status": {"$ne": "resolved"}, | |
| "created_at": {"$gte": since}, | |
| "location": { | |
| "$nearSphere": { | |
| "$geometry": {"type": "Point", "coordinates": coordinates}, | |
| "$maxDistance": CORROBORATE_RADIUS_M, | |
| } | |
| }, | |
| } | |
| ) | |
| return [doc async for doc in cursor] | |
| async def bump_witness(db, alert_id: ObjectId, user_id: str) -> dict | None: | |
| """Idempotently add a witness — one user can only confirm once.""" | |
| return await db.alerts.find_one_and_update( | |
| {"_id": alert_id, "witnessed_by": {"$ne": user_id}}, | |
| { | |
| "$addToSet": {"witnessed_by": user_id}, | |
| "$inc": {"witnesses": 1}, | |
| }, | |
| return_document=True, | |
| ) | |