"""Client Open-Meteo (gratuit, sans clé API)."""
import json
import os
from datetime import datetime, timezone
from pathlib import Path
from typing import Any

import httpx

CACHE_PATH = Path(os.environ.get("UPLOAD_DIR", "/data")).parent / "meteo_cache.json"
CACHE_TTL_SECONDS = 3 * 3600  # 3h

WMO_LABELS = {
    0: "Ensoleillé",
    1: "Principalement ensoleillé",
    2: "Partiellement nuageux",
    3: "Couvert",
    45: "Brouillard",
    48: "Brouillard givrant",
    51: "Bruine légère",
    53: "Bruine modérée",
    55: "Bruine dense",
    61: "Pluie légère",
    63: "Pluie modérée",
    65: "Pluie forte",
    71: "Neige légère",
    73: "Neige modérée",
    75: "Neige forte",
    80: "Averses légères",
    81: "Averses modérées",
    82: "Averses violentes",
    85: "Averses de neige",
    95: "Orage",
    96: "Orage avec grêle",
    99: "Orage violent",
}
WMO_ICONS = {
    0: "☀️",
    1: "🌤",
    2: "⛅",
    3: "☁️",
    45: "🌫",
    48: "🌫",
    51: "🌦",
    53: "🌦",
    55: "🌧",
    61: "🌦",
    63: "🌧",
    65: "🌧",
    71: "🌨",
    73: "🌨",
    75: "❄️",
    80: "🌦",
    81: "🌧",
    82: "⛈",
    85: "🌨",
    95: "⛈",
    96: "⛈",
    99: "⛈",
}


def _cache_fresh() -> dict | None:
    if not CACHE_PATH.exists():
        return None
    try:
        data = json.loads(CACHE_PATH.read_text())
        cached_at = datetime.fromisoformat(
            data.get("cached_at", "2000-01-01T00:00:00+00:00")
        )
        if (datetime.now(timezone.utc) - cached_at).total_seconds() < CACHE_TTL_SECONDS:
            return data
    except Exception:
        pass
    return None


def fetch_forecast(
    lat: float = 45.14, lon: float = 4.12, days: int = 14
) -> dict[str, Any]:
    cached = _cache_fresh()
    if cached:
        return cached

    url = "https://api.open-meteo.com/v1/forecast"
    params = {
        "latitude": lat,
        "longitude": lon,
        "daily": "temperature_2m_max,temperature_2m_min,precipitation_sum,windspeed_10m_max,weathercode",
        "timezone": "Europe/Paris",
        "forecast_days": min(days, 16),
    }
    try:
        r = httpx.get(url, params=params, timeout=10)
        r.raise_for_status()
        raw = r.json()
    except Exception as e:
        return {"error": str(e), "days": []}

    daily = raw.get("daily", {})
    dates = daily.get("time", [])
    result_days = []
    for i, d in enumerate(dates):
        code = int(daily.get("weathercode", [0] * len(dates))[i] or 0)
        result_days.append(
            {
                "date": d,
                "t_max": daily.get("temperature_2m_max", [None] * len(dates))[i],
                "t_min": daily.get("temperature_2m_min", [None] * len(dates))[i],
                "pluie_mm": daily.get("precipitation_sum", [0] * len(dates))[i] or 0,
                "vent_kmh": daily.get("windspeed_10m_max", [0] * len(dates))[i] or 0,
                "code": code,
                "label": WMO_LABELS.get(code, "Inconnu"),
                "icone": WMO_ICONS.get(code, "🌡"),
            }
        )

    data = {
        "cached_at": datetime.now(timezone.utc).isoformat(),
        "days": result_days,
    }
    try:
        CACHE_PATH.parent.mkdir(parents=True, exist_ok=True)
        CACHE_PATH.write_text(json.dumps(data, ensure_ascii=False))
    except Exception:
        pass
    return data