from __future__ import annotations

from datetime import date
from pathlib import Path

import yaml

from src.data.exceptions import UnknownInstrumentError
from src.data.models import Instrument


def load_instruments(config_path: Path) -> dict[str, Instrument]:
    with config_path.open("r", encoding="utf-8") as handle:
        payload = yaml.safe_load(handle) or {}

    instruments: dict[str, Instrument] = {}
    for key, raw in (payload.get("instruments") or {}).items():
        instruments[key] = Instrument(
            key=key,
            name=raw["name"],
            index_code=str(raw["index_code"]),
            provider_symbol=str(raw["provider_symbol"]),
            exchange=str(raw["exchange"]),
            price_type=str(raw["price_type"]),
            bootstrap_start=date.fromisoformat(str(raw["bootstrap_start"])),
        )
    return instruments


def get_instrument(instruments: dict[str, Instrument], key: str) -> Instrument:
    try:
        return instruments[key]
    except KeyError as exc:
        raise UnknownInstrumentError(f"Unknown instrument: {key}") from exc