from dataclasses import replace

from lyra_worker.confidence import score_confidence
from lyra_worker.quality import rank_key
from lyra_worker.types import Candidate, MBTarget


def rank_candidates(
    target: MBTarget, candidates: list[Candidate], min_confidence: float = 0.7
) -> list[Candidate]:
    """Score, gate by confidence, and sort best-first (quality, then confidence)."""
    scored = [replace(c, confidence=score_confidence(target, c)) for c in candidates]
    kept = [c for c in scored if c.confidence >= min_confidence]
    kept.sort(key=lambda c: (rank_key(c), c.confidence), reverse=True)
    return kept