"""Routes for quantitative analysis: risk metrics, CAPM, normality, unit root."""

import functools
import logging
from collections.abc import Awaitable, Callable
from typing import ParamSpec, TypeVar

from fastapi import APIRouter, HTTPException, Path, Query

from models import SYMBOL_PATTERN, ApiResponse
import quantitative_service

logger = logging.getLogger(__name__)

router = APIRouter(prefix="/api/v1")

P = ParamSpec("P")
R = TypeVar("R")


def _validate_symbol(symbol: str) -> str:
    if not SYMBOL_PATTERN.match(symbol):
        raise HTTPException(status_code=400, detail="Invalid symbol format")
    return symbol.upper()


def _safe(fn: Callable[P, Awaitable[R]]) -> Callable[P, Awaitable[R]]:
    @functools.wraps(fn)
    async def wrapper(*args: P.args, **kwargs: P.kwargs) -> R:
        try:
            return await fn(*args, **kwargs)
        except HTTPException:
            raise
        except Exception:
            logger.exception("Upstream data error")
            raise HTTPException(
                status_code=502,
                detail="Data provider error. Check server logs.",
            )
    return wrapper  # type: ignore[return-value]


@router.get("/stock/{symbol}/performance", response_model=ApiResponse)
@_safe
async def stock_performance(
    symbol: str = Path(..., min_length=1, max_length=20),
    days: int = Query(default=365, ge=30, le=3650),
):
    """Performance metrics: Sharpe, Sortino, max drawdown, volatility."""
    symbol = _validate_symbol(symbol)
    data = await quantitative_service.get_performance_metrics(symbol, days=days)
    return ApiResponse(data=data)


@router.get("/stock/{symbol}/capm", response_model=ApiResponse)
@_safe
async def stock_capm(symbol: str = Path(..., min_length=1, max_length=20)):
    """CAPM: beta, alpha, systematic and idiosyncratic risk."""
    symbol = _validate_symbol(symbol)
    data = await quantitative_service.get_capm(symbol)
    return ApiResponse(data=data)


@router.get("/stock/{symbol}/normality", response_model=ApiResponse)
@_safe
async def stock_normality(
    symbol: str = Path(..., min_length=1, max_length=20),
    days: int = Query(default=365, ge=30, le=3650),
):
    """Normality tests: Jarque-Bera, Shapiro-Wilk on returns."""
    symbol = _validate_symbol(symbol)
    data = await quantitative_service.get_normality_test(symbol, days=days)
    return ApiResponse(data=data)


@router.get("/stock/{symbol}/unitroot", response_model=ApiResponse)
@_safe
async def stock_unitroot(
    symbol: str = Path(..., min_length=1, max_length=20),
    days: int = Query(default=365, ge=30, le=3650),
):
    """Unit root tests: ADF, KPSS for stationarity."""
    symbol = _validate_symbol(symbol)
    data = await quantitative_service.get_unitroot_test(symbol, days=days)
    return ApiResponse(data=data)