from __future__ import annotations

import os
from datetime import datetime, timezone

import requests

from .bitstamp_rate_limit import throttle_bitstamp_request
from .storage import get_connection

BITSTAMP_BASE_URL = "https://www.bitstamp.net"
FX_REFRESH_SECONDS = 15 * 60
FX_CACHE_TTL_SECONDS = 60


def fetch_eur_usd() -> dict:
    cache_key = "bitstamp:fx:eur_usd"
    cached = __import__("exec_mcp.repo", fromlist=["cache_get"]).cache_get(cache_key)
    if cached is not None:
        return cached
    throttle_bitstamp_request()
    response = requests.get(f"{BITSTAMP_BASE_URL}/api/v2/eur_usd/", timeout=30)
    response.raise_for_status()
    payload = response.json()
    __import__("exec_mcp.repo", fromlist=["cache_put"]).cache_put(
        cache_key,
        payload,
        max(int(os.getenv("BITSTAMP_FX_CACHE_TTL_SECONDS", str(FX_CACHE_TTL_SECONDS))), 0),
    )
    return payload


def save_eur_usd(payload: dict) -> None:
    captured_at = datetime.now(timezone.utc).isoformat()
    with get_connection() as conn:
        conn.execute(
            """
            INSERT INTO bitstamp_fx_rates (pair, buy, sell, payload_json, captured_at)
            VALUES (?, ?, ?, ?, ?)
            ON CONFLICT(pair) DO UPDATE SET
                buy=excluded.buy,
                sell=excluded.sell,
                payload_json=excluded.payload_json,
                captured_at=excluded.captured_at
            """,
            (
                "eur_usd",
                str(payload.get("buy", "")),
                str(payload.get("sell", "")),
                __import__("json").dumps(payload),
                captured_at,
            ),
        )
        conn.commit()


def load_eur_usd() -> dict | None:
    with get_connection() as conn:
        row = conn.execute("SELECT buy, sell, payload_json FROM bitstamp_fx_rates WHERE pair = ?", ("eur_usd",)).fetchone()
    if row is None:
        return None
    return __import__("json").loads(row["payload_json"])


def refresh_eur_usd() -> dict:
    payload = fetch_eur_usd()
    save_eur_usd(payload)
    return payload