from __future__ import annotations
from typing import List
from .dsl import MarketSignal, PlanDelta

class Coordinator:
    """
    Lightweight ADMM-like coordinator.
    It collects MarketSignals from multiple venues and emits a PlanDelta
    representing a synchronized hedging action.
    This is a minimal, deterministic stub suitable for MVP testing.
    """
    def __init__(self, contract_id: str = "default-contract"):
        self.contract_id = contract_id
        self.last_plan: PlanDelta | None = None

    def coordinate(self, signals: List[MarketSignal], author: str = "coordinator") -> PlanDelta:
        # Very small heuristic: if two assets present, generate a delta-neutral hedge
        actions: List[dict] = []
        # Simple rule: create a hedge adjustment based on price relative to last plan
        for s in signals:
            if s.asset.type == "equity":
                actions.append({"action": "hedge", "symbol": s.asset.symbol, "size": -0.5, "price": s.price, "ts": s.timestamp})
            elif s.asset.type == "option":
                actions.append({"action": "adjust", "symbol": s.asset.symbol, "size": -0.25, "premium": s.price, "ts": s.timestamp})
        plan = PlanDelta(delta=actions, timestamp=signals[0].timestamp if signals else 0.0, author=author, contract_id=self.contract_id)
        self.last_plan = plan
        return plan