"""
Economic Calendar (Financial Modeling Prep, free tier).

Fetches upcoming high-impact macro events (FOMC, CPI, NFP, GDP, rate
decisions...) that move risk assets including crypto. Needs a free API key:

  FMP_API_KEY=...   (free at https://site.financialmodelingprep.com)

Like the NewsData collector, this skips gracefully when the key is absent, so
the app runs fine without it — the Economic Calendar / Market Impact Forecast
panels simply show "add FMP_API_KEY".
"""

import os
import logging
import requests
from datetime import datetime, timezone, timedelta

logger = logging.getLogger(__name__)

_FMP_URL = "https://financialmodelingprep.com/api/v3/economic_calendar"

# Countries whose data actually moves crypto (US dominates)
_COUNTRIES = {"US", "EA", "GB", "CN"}
# Only events that matter — match on keywords (FMP impact field is unreliable)
_HIGH_IMPACT_KEYS = [
    "fomc", "fed ", "federal funds", "interest rate", "rate decision",
    "cpi", "core cpi", "inflation", "ppi", "nonfarm", "non-farm", "nfp",
    "unemployment", "jobless", "gdp", "pce", "powell", "fed chair",
    "retail sales", "ism", "treasury", "consumer price",
]


def fmp_configured() -> bool:
    return bool(os.getenv("FMP_API_KEY"))


def _impact_rank(ev: dict) -> int:
    name = (ev.get("event") or "").lower()
    imp = (ev.get("impact") or "").lower()
    if any(k in name for k in ("fomc", "rate decision", "interest rate", "cpi", "nonfarm", "nfp", "powell")):
        return 3
    if imp == "high" or any(k in name for k in _HIGH_IMPACT_KEYS):
        return 2
    if imp == "medium":
        return 1
    return 0


class EconomicCalendar:
    def fetch(self, days_ahead: int = 7) -> list[dict]:
        from monitoring import monitor
        if not fmp_configured():
            return []
        now = datetime.now(timezone.utc)
        params = {
            "from": now.strftime("%Y-%m-%d"),
            "to":   (now + timedelta(days=days_ahead)).strftime("%Y-%m-%d"),
            "apikey": os.getenv("FMP_API_KEY"),
        }
        try:
            resp = requests.get(_FMP_URL, params=params, timeout=15)
            resp.raise_for_status()
            data = resp.json()
            monitor.source_ok("FMP:calendar", len(data) if isinstance(data, list) else 0)
        except Exception as exc:
            monitor.source_failure("FMP:calendar", str(exc)[:120])
            return []

        if not isinstance(data, list):
            return []

        events = []
        for ev in data:
            country = (ev.get("country") or "").upper()
            if country not in _COUNTRIES:
                continue
            rank = _impact_rank(ev)
            if rank < 2:        # keep only high-impact
                continue
            dt = _parse_dt(ev.get("date"))
            if not dt or dt < now - timedelta(hours=2):
                continue        # past
            events.append({
                "event":    ev.get("event", ""),
                "country":  country,
                "datetime": dt.isoformat(),
                "hours_until": round((dt - now).total_seconds() / 3600, 1),
                "impact":   "HIGH" if rank >= 3 else "MED",
                "estimate": ev.get("estimate"),
                "previous": ev.get("previous"),
            })

        events.sort(key=lambda e: e["datetime"])
        return events[:12]


def _parse_dt(s: str):
    if not s:
        return None
    for fmt in ("%Y-%m-%d %H:%M:%S", "%Y-%m-%dT%H:%M:%S", "%Y-%m-%d"):
        try:
            return datetime.strptime(s, fmt).replace(tzinfo=timezone.utc)
        except Exception:
            continue
    return None