"""DHL Shipment Tracking – Unified API.

Kostenloser Key: https://developer.dhl.com (API "Shipment Tracking - Unified")
"""
import httpx

API = "https://api-eu.dhl.com/track/shipments"

STATUS = {
    "pre-transit": "inforeceived",
    "transit": "intransit",
    "delivered": "delivered",
    "failure": "failed",
    "unknown": "unknown",
}


def _place(loc: dict | None) -> str | None:
    addr = (loc or {}).get("address")
    if not addr:
        return None
    return ", ".join(filter(None, [addr.get("addressLocality"), addr.get("countryCode")])) or None


async def track_dhl(number: str, key: str) -> dict | None:
    async with httpx.AsyncClient(timeout=15) as client:
        res = await client.get(
            API,
            params={"trackingNumber": number, "language": "de"},
            headers={"DHL-API-Key": key, "Accept": "application/json"},
        )
    if res.status_code == 404:
        return None  # keine DHL-Sendung -> nächsten Anbieter probieren
    res.raise_for_status()

    shipments = res.json().get("shipments") or []
    if not shipments:
        return None
    s = shipments[0]
    status = s.get("status") or {}

    events = [
        {"time": e.get("timestamp"), "description": e.get("description") or e.get("status"), "location": _place(e.get("location"))}
        for e in s.get("events") or []
    ]

    eta = None
    if s.get("estimatedTimeOfDelivery"):
        eta = {"from": s["estimatedTimeOfDelivery"], "to": None}
    elif s.get("estimatedDeliveryTimeFrame"):
        frame = s["estimatedDeliveryTimeFrame"]
        eta = {"from": frame.get("estimatedFrom"), "to": frame.get("estimatedThrough")}

    return {
        "source": "DHL API",
        "carrier": "DHL Express" if s.get("service") == "express" else "DHL",
        "status": STATUS.get(status.get("statusCode"), "unknown"),
        "statusDetail": status.get("description") or status.get("status"),
        "eta": eta,
        "deliveredAt": status.get("timestamp") if status.get("statusCode") == "delivered" else None,
        "origin": _place(s.get("origin")),
        "destination": _place(s.get("destination")),
        "events": events,
    }