"""
Binance data provider.
Used primarily for high-quality OHLCV data (klines endpoint).
No API key required for public market data.
"""

import httpx
from config import BINANCE_BASE_URL, TIMEFRAME_TO_BINANCE
from errors import SymbolNotFoundError, ProviderError, UnsupportedTimeframeError


def _binance_symbol(symbol: str) -> str:
    sym = symbol.upper()
    if not sym.endswith("USDT"):
        sym = sym + "USDT"
    return sym


async def fetch_price(symbol: str) -> dict:
    import time
    binance_sym = _binance_symbol(symbol)
    url = f"{BINANCE_BASE_URL}/ticker/price"
    params = {"symbol": binance_sym}

    async with httpx.AsyncClient(timeout=10.0) as client:
        try:
            resp = await client.get(url, params=params)
            if resp.status_code == 400:
                raise SymbolNotFoundError(f"Symbol not found on Binance: {symbol}")
            resp.raise_for_status()
        except httpx.HTTPStatusError as e:
            raise ProviderError(f"Binance HTTP error: {e.response.status_code}") from e
        except httpx.RequestError as e:
            raise ProviderError(f"Binance request failed: {e}") from e

    data = resp.json()
    return {"symbol": symbol.upper(), "price": float(data["price"]), "timestamp": int(time.time())}


async def fetch_ohlcv(symbol: str, timeframe: str, limit: int = 100) -> dict:
    interval = TIMEFRAME_TO_BINANCE.get(timeframe)
    if not interval:
        raise UnsupportedTimeframeError(f"Unsupported timeframe: {timeframe}. Supported: {list(TIMEFRAME_TO_BINANCE.keys())}")

    binance_sym = _binance_symbol(symbol)
    url = f"{BINANCE_BASE_URL}/klines"
    params = {"symbol": binance_sym, "interval": interval, "limit": min(limit, 1000)}

    async with httpx.AsyncClient(timeout=15.0) as client:
        try:
            resp = await client.get(url, params=params)
            if resp.status_code == 400:
                raise SymbolNotFoundError(f"Symbol not found on Binance: {symbol}")
            resp.raise_for_status()
        except httpx.HTTPStatusError as e:
            raise ProviderError(f"Binance klines HTTP error: {e.response.status_code}") from e
        except httpx.RequestError as e:
            raise ProviderError(f"Binance klines request failed: {e}") from e

    raw = resp.json()
    if not raw:
        raise ProviderError(f"Binance returned empty klines for {symbol} {timeframe}")

    candles = [[int(row[0] / 1000), float(row[1]), float(row[2]), float(row[3]), float(row[4]), float(row[5])] for row in raw]
    return {"symbol": symbol.upper(), "timeframe": timeframe, "candles": candles}