import httpx
import asyncio
from datetime import datetime, timezone

# USGS Earthquake Hazards Program - completely free, no API key
# Significant earthquakes (M 4.5+) from the past 7 days
USGS_URL = "https://earthquake.usgs.gov/earthquakes/feed/v1.0/summary/4.5_week.geojson"


async def fetch_earthquakes() -> list:
    """
    Fetches real earthquake data from USGS.
    Returns quakes with M >= 4.5 from the past week.
    """
    try:
        async with httpx.AsyncClient() as client:
            response = await client.get(USGS_URL, timeout=12.0)
            if response.status_code != 200:
                print(f"[SEISMIC] USGS returned {response.status_code}")
                return []

            data = response.json()
            quakes = []

            for feature in data.get("features", []):
                props = feature.get("properties", {})
                geom  = feature.get("geometry", {})
                coords = geom.get("coordinates", [])

                if len(coords) < 2:
                    continue

                lon, lat = coords[0], coords[1]
                depth_km = coords[2] if len(coords) > 2 else 0
                mag = props.get("mag")

                if mag is None:
                    continue
                # Validate coordinates
                if not (-90 <= lat <= 90) or not (-180 <= lon <= 180):
                    continue

                # Severity classification
                if mag >= 7.0:
                    severity = "MAJOR"
                elif mag >= 6.0:
                    severity = "STRONG"
                elif mag >= 5.0:
                    severity = "MODERATE"
                else:
                    severity = "MINOR"

                # Convert USGS epoch ms to ISO string
                epoch_ms = props.get("time", 0)
                try:
                    dt = datetime.fromtimestamp(epoch_ms / 1000, tz=timezone.utc)
                    time_str = dt.strftime("%Y-%m-%d %H:%M UTC")
                except Exception:
                    time_str = "Unknown"

                quakes.append({
                    "id":        feature.get("id", ""),
                    "title":     props.get("title", "Earthquake"),
                    "place":     props.get("place", "Unknown Location"),
                    "lat":       lat,
                    "lon":       lon,
                    "depth_km":  round(depth_km, 1),
                    "magnitude": mag,
                    "severity":  severity,
                    "time":      time_str,
                    "url":       props.get("url", ""),
                    "type":      "earthquake",
                    "felt":      props.get("felt", 0),
                    "tsunami":   props.get("tsunami", 0),
                })

            # Sort by magnitude descending
            quakes.sort(key=lambda q: q["magnitude"], reverse=True)
            print(f"[SEISMIC] {len(quakes)} earthquakes (M≥4.5) — strongest: M{quakes[0]['magnitude'] if quakes else 'N/A'}")
            return quakes

    except Exception as e:
        print(f"[SEISMIC] Fetch error: {e}")
        return []


if __name__ == "__main__":
    result = asyncio.run(fetch_earthquakes())
    print(f"Earthquakes: {len(result)}")
    for q in result[:5]:
        print(f"  M{q['magnitude']} {q['severity']} — {q['place']}")