from __future__ import annotations

import httpx

from app.market.base import MarketData
from app.schemas import Candle

BASE_URL = "https://api.binance.com"


def to_exchange_symbol(symbol: str) -> str:
    return symbol.replace("/", "").upper()


class BinanceMarketData(MarketData):
    """Public Binance spot market data over REST (no API key required)."""

    def __init__(self, base_url: str = BASE_URL, timeout: float = 10.0) -> None:
        self._client = httpx.AsyncClient(base_url=base_url, timeout=timeout)

    async def fetch_candles(self, symbol: str, timeframe: str, limit: int) -> list[Candle]:
        response = await self._client.get(
            "/api/v3/klines",
            params={
                "symbol": to_exchange_symbol(symbol),
                "interval": timeframe,
                "limit": limit,
            },
        )
        response.raise_for_status()
        return [
            Candle(
                ts=int(row[0]),
                open=float(row[1]),
                high=float(row[2]),
                low=float(row[3]),
                close=float(row[4]),
                volume=float(row[5]),
            )
            for row in response.json()
        ]

    async def fetch_price(self, symbol: str) -> float:
        response = await self._client.get(
            "/api/v3/ticker/price",
            params={"symbol": to_exchange_symbol(symbol)},
        )
        response.raise_for_status()
        return float(response.json()["price"])

    async def close(self) -> None:
        await self._client.aclose()