"""Starter data feed adapter (mock).

Pretend to ingest options and equities data from a data feed. This module
provides a tiny interface compatible with the MVP's core primitives.
"""
from __future__ import annotations
from typing import Dict, List


class DataFeedAdapter:
    def __init__(self):
        pass

    def fetch_option_stream(self) -> List[Dict[str, float]]:
        # Mock option stream: delta exposure signals
        return [{"instrument": "AAPL_20240120_150C", "greeks": {"delta": 0.5}}]

    def fetch_equity_stream(self) -> List[Dict[str, float]]:
        return [{"instrument": "AAPL", "price": 150.0}]