"""Market data access layer with caching support."""

from __future__ import annotations

import asyncio
import logging
from datetime import UTC, datetime
from typing import Any

from app.services.cache import CacheService
from app.strategies.engine import StrategySelectionEngine

logger = logging.getLogger(__name__)

try:
    import yfinance as yf
except ImportError:  # pragma: no cover - optional dependency
    yf = None


class DataService:
    """Fetches portfolio and market data, using Redis when available."""

    def __init__(self, cache: CacheService, default_symbol: str = "GLD") -> None:
        self.cache = cache
        self.default_symbol = default_symbol

    async def get_portfolio(self, symbol: str | None = None) -> dict[str, Any]:
        ticker = (symbol or self.default_symbol).upper()
        cache_key = f"portfolio:{ticker}"

        cached = await self.cache.get_json(cache_key)
        if cached:
            return cached

        quote = await self.get_quote(ticker)
        portfolio = {
            "symbol": ticker,
            "spot_price": quote["price"],
            "portfolio_value": round(quote["price"] * 1000, 2),
            "loan_amount": 600_000.0,
            "ltv_ratio": round(600_000.0 / max(quote["price"] * 1000, 1), 4),
            "updated_at": datetime.now(UTC).isoformat(),
            "source": quote["source"],
        }
        await self.cache.set_json(cache_key, portfolio)
        return portfolio

    async def get_quote(self, symbol: str) -> dict[str, Any]:
        cache_key = f"quote:{symbol}"
        cached = await self.cache.get_json(cache_key)
        if cached:
            return cached

        quote = await self._fetch_quote(symbol)
        await self.cache.set_json(cache_key, quote)
        return quote

    async def get_options_chain(self, symbol: str | None = None) -> dict[str, Any]:
        ticker = (symbol or self.default_symbol).upper()
        cache_key = f"options:{ticker}"

        cached = await self.cache.get_json(cache_key)
        if cached:
            return cached

        quote = await self.get_quote(ticker)
        base_price = quote["price"]
        options_chain = {
            "symbol": ticker,
            "updated_at": datetime.now(UTC).isoformat(),
            "calls": [
                {
                    "strike": round(base_price * 1.05, 2),
                    "premium": round(base_price * 0.03, 2),
                    "expiry": "2026-06-19",
                },
                {
                    "strike": round(base_price * 1.10, 2),
                    "premium": round(base_price * 0.02, 2),
                    "expiry": "2026-09-18",
                },
            ],
            "puts": [
                {
                    "strike": round(base_price * 0.95, 2),
                    "premium": round(base_price * 0.028, 2),
                    "expiry": "2026-06-19",
                },
                {
                    "strike": round(base_price * 0.90, 2),
                    "premium": round(base_price * 0.018, 2),
                    "expiry": "2026-09-18",
                },
            ],
            "source": quote["source"],
        }
        await self.cache.set_json(cache_key, options_chain)
        return options_chain

    async def get_strategies(self, symbol: str | None = None) -> dict[str, Any]:
        ticker = (symbol or self.default_symbol).upper()
        quote = await self.get_quote(ticker)
        engine = StrategySelectionEngine(spot_price=quote["price"] if ticker != "GLD" else 460.0)

        return {
            "symbol": ticker,
            "updated_at": datetime.now(UTC).isoformat(),
            "paper_parameters": {
                "portfolio_value": engine.portfolio_value,
                "loan_amount": engine.loan_amount,
                "margin_call_threshold": engine.margin_call_threshold,
                "spot_price": engine.spot_price,
                "volatility": engine.volatility,
                "risk_free_rate": engine.risk_free_rate,
            },
            "strategies": engine.compare_all_strategies(),
            "recommendations": {
                profile: engine.recommend(profile) for profile in ("conservative", "balanced", "cost_sensitive")
            },
            "sensitivity_analysis": engine.sensitivity_analysis(),
        }

    async def _fetch_quote(self, symbol: str) -> dict[str, Any]:
        if yf is None:
            return self._fallback_quote(symbol, source="fallback")

        try:
            ticker = yf.Ticker(symbol)
            history = await asyncio.to_thread(ticker.history, period="5d", interval="1d")
            if history.empty:
                return self._fallback_quote(symbol, source="fallback")

            closes = history["Close"]
            last = float(closes.iloc[-1])
            previous = float(closes.iloc[-2]) if len(closes) > 1 else last
            change = round(last - previous, 4)
            change_percent = round((change / previous) * 100, 4) if previous else 0.0
            return {
                "symbol": symbol,
                "price": round(last, 4),
                "change": change,
                "change_percent": change_percent,
                "updated_at": datetime.now(UTC).isoformat(),
                "source": "yfinance",
            }
        except Exception as exc:  # pragma: no cover - network dependent
            logger.warning("Failed to fetch %s from yfinance: %s", symbol, exc)
            return self._fallback_quote(symbol, source="fallback")

    @staticmethod
    def _fallback_quote(symbol: str, source: str) -> dict[str, Any]:
        return {
            "symbol": symbol,
            "price": 215.0,
            "change": 0.0,
            "change_percent": 0.0,
            "updated_at": datetime.now(UTC).isoformat(),
            "source": source,
        }