import logging
from typing import Optional

import requests

from database import MotionDatabase

logger = logging.getLogger(__name__)


def normalize_mp_name(
    achternaam: str, initialen: Optional[str], tussenvoegsel: Optional[str]
) -> str:
    """Reconstruct ActorNaam format used in voting_results keys.

    Format: "{Tussenvoegsel} {Achternaam}, {Initialen}" with sensible stripping when
    tussenvoegsel is missing.
    """
    parts = []
    if tussenvoegsel:
        parts.append(tussenvoegsel)
    parts.append(achternaam)
    name = " ".join(parts).strip()

    # Ensure the displayed name starts with an uppercase letter so
    # ORDER BY mp_name behaves predictably across databases that may
    # sort uppercase before lowercase. Only change the first character
    # to upper-case to avoid lowercasing other letters (e.g. hyphenated
    # or already capitalized parts).
    if name and name[0].islower():
        name = name[0].upper() + name[1:]
    if initialen:
        name = f"{name}, {initialen}"
    return name


_ODATA_BASE = "https://gegevensmagazijn.tweedekamer.nl/OData/v4/2.0"
_PAGE_SIZE = 250


def fetch_mp_metadata(
    db_path: str,
    odata_url: str = f"{_ODATA_BASE}/FractieZetelPersoon",
) -> int:
    """Fetch MP party membership and tenure from OData and upsert into DB.

    Paginates through all records using $skip.  Uses Fractie.Afkorting as
    the party name so it matches the abbreviations used in mp_votes.

    Returns the number of records processed (inserted or updated).
    """
    expand = "$expand=FractieZetel($expand=Fractie),Persoon"
    session = requests.Session()
    db = MotionDatabase(db_path)
    processed = 0
    skip = 0

    while True:
        url = f"{odata_url}?{expand}&$top={_PAGE_SIZE}&$skip={skip}"
        try:
            resp = session.get(url, timeout=30)
            resp.raise_for_status()
            data = resp.json()
        except Exception as e:
            logger.error("Failed to fetch MP metadata (skip=%d): %s", skip, e)
            raise

        values = data.get("value") if isinstance(data, dict) else None
        if values is None:
            logger.error("Unexpected OData payload at skip=%d; missing 'value'", skip)
            break

        if not values:
            break  # no more pages

        for item in values:
            try:
                if item.get("Verwijderd"):
                    continue

                persoon = item.get("Persoon") or {}
                fractiezetel = item.get("FractieZetel") or {}
                fractie = fractiezetel.get("Fractie") or {}

                achternaam = persoon.get("Achternaam")
                initialen = persoon.get("Initialen")
                tussenvoegsel = persoon.get("Tussenvoegsel")
                persoon_id = persoon.get("Id")

                # Use Afkorting (e.g. "VVD", "GroenLinks-PvdA") to match mp_votes party column
                party = fractie.get("Afkorting") or fractie.get("NaamNL")
                van = item.get("Van")
                tot_en_met = item.get("TotEnMet")

                if not achternaam:
                    logger.debug("Skipping record without achternaam: %s", item)
                    continue

                mp_name = normalize_mp_name(achternaam, initialen, tussenvoegsel)

                db.upsert_mp_metadata(
                    mp_name=mp_name,
                    party=party,
                    van=van,
                    tot_en_met=tot_en_met,
                    persoon_id=persoon_id,
                )
                processed += 1
            except Exception:
                logger.exception("Error processing OData item: %s", item)

        logger.debug("Fetched page skip=%d, got %d records", skip, len(values))
        if len(values) < _PAGE_SIZE:
            break  # last page
        skip += _PAGE_SIZE

    logger.info("Processed %d MP metadata records", processed)
    return processed