# -----------------------------------------------------------------------------
# Immo-Ka — Agrégateur de maisons à vendre (province de Québec)
# Auteur : Simon-Pierre Boucher — contact@spboucher.ai
# mortgage/providers/scotiabank.py : Banque Scotia — API JSON publique
#   dmtsms.scotiabank.com (celle que consomme leur propre page de taux).
#   nonspecialmortgage = taux affichés ; varmortgage = slots promotionnels
#   (le mapping slot -> produit vient de la page ; on ne garde que les slots
#   dont l'identité est connue, avec confiance réduite).
# -----------------------------------------------------------------------------
from __future__ import annotations

import json

from .base import RateProvider

POSTED_URL = "https://dmtsms.scotiabank.com/api/rates/daily/nonspecialmortgage"
PROMO_URL = "https://dmtsms.scotiabank.com/api/rates/daily/varmortgage"
PAGE_URL = ("https://www.scotiabank.com/ca/en/personal/rates-prices/"
            "mortgages-rates.html")

# PRODUCT -> (rate_type, insured_status, nom, purpose)
POSTED_MAP = {
    "N.H.A. RESIDENTIAL, ETC": ("fixed", "insured", "Fixe affiché (assuré LNH)"),
    "CONVENTIONAL RESIDENTIAL, ETC": ("fixed", "uninsured", "Fixe affiché (conventionnel)"),
    "ULTIMATE VARIABLE RATE": ("variable", "unknown", "Ultimate Variable"),
    "OPEN": ("fixed", "unknown", "Fixe ouvert"),
    "FLEXIBLE": ("fixed", "unknown", "Flexible"),
}

# Slots promotionnels dont l'identité est documentée sur la page Scotia
# (2026-08). Confiance réduite : si Scotia réordonne ses slots, la validation
# et la comparaison croisée limitent les dégâts.
PROMO_SLOTS = {
    "MORTGAGE PROMOTIONAL 1": ("variable", 60, "Flex Value fermé 5 ans (variable)"),
    "MORTGAGE PROMOTIONAL 2": ("variable", 36, "Ultimate Variable 3 ans"),
    "MORTGAGE PROMOTIONAL 3": ("variable", 60, "Flex Value ouvert 5 ans (variable)"),
}


def _term_months(t: dict) -> int | None:
    try:
        v = int(t["TERM_VALUE"])
    except (KeyError, ValueError, TypeError):
        return None
    unit = (t.get("TERM_UNIT") or "").upper()
    if unit == "Y":
        return v * 12
    if unit == "M":
        return v
    return None


class ScotiabankProvider(RateProvider):
    provider_id = "scotiabank"
    institution = "Banque Scotia"
    source_url = PAGE_URL
    request_delay = 1.0

    def fetch(self) -> list[dict]:
        posted = self.get(POSTED_URL).text
        try:
            promo = self.get(PROMO_URL).text
        except Exception:  # noqa: BLE001 — promos facultatives
            promo = ""
        return self.parse(posted) + (self.parse_promos(promo) if promo else [])

    def parse(self, payload: str) -> list[dict]:
        data = json.loads(payload)
        out: list[dict] = []
        for prod in data.get("data") or []:
            name = (prod.get("PRODUCT") or "").strip()
            if name not in POSTED_MAP:
                continue  # produits chalet/cap/right-rate : hors périmètre
            rtype, insured, label = POSTED_MAP[name]
            for t in prod.get("TERMS") or []:
                term = _term_months(t)
                rate = t.get("RATE")
                if term is None or not isinstance(rate, (int, float)) or rate <= 0:
                    continue
                out.append(self.make_product(
                    rate=float(rate), rate_type=rtype, term_months=term,
                    kind="posted", product_name=label,
                    insured_status=insured,
                    conditions=name,
                    raw={"product": name, "term": t}))
        return out

    def parse_promos(self, payload: str) -> list[dict]:
        data = json.loads(payload)
        out: list[dict] = []
        for prod in data.get("data") or []:
            name = (prod.get("PRODUCT") or "").strip()
            if name not in PROMO_SLOTS:
                continue
            rate = prod.get("RATE")
            if not isinstance(rate, (int, float)) or rate <= 0:
                continue  # slot inutilisé
            rtype, term, label = PROMO_SLOTS[name]
            out.append(self.make_product(
                rate=float(rate), rate_type=rtype, term_months=term,
                kind="special", product_name=label, confidence=0.8,
                conditions=f"Slot promotionnel Scotia ({name})",
                raw={"product": name, "rate": rate}))
        return out