"""Lightweight cross-venue execution router (experimental)."""
from __future__ import annotations

from typing import List, Optional

from deltaforge_mvp.core import PlanDelta


class ExecutionRouter:
    """Simple round-robin routing of a PlanDelta to available venues.

    This is a tiny, self-contained shim that demonstrates how a real executor
    would dispatch plan deltas to venue adapters with latency/fees metadata.
    """

    def __init__(self, venues: Optional[List[str]] = None):
        self.venues = venues or []
        self._idx = 0

    def route(self, plan: PlanDelta) -> dict:
        """Route the given plan to a venue (or no venue if unknown).

        Returns a dict with routing metadata that downstream systems can consume.
        """
        if not self.venues:
            return {"routed": False, "reason": "no_venues_configured"}

        venue = self.venues[self._idx % len(self.venues)]
        self._idx += 1
        # Attach simple routing metadata to the plan (clone-like behavior)
        routed = PlanDelta(
            deltas=plan.deltas,
            confidence=plan.confidence if hasattr(plan, "confidence") else 1.0,
            venue=venue,
            author=plan.author,
            timestamp=plan.timestamp,
            signature=plan.signature,
        )
        return {
            "routed": True,
            "venue": venue,
            "plan": routed,
        }