services/reward_service.py

"""Reward shaping logic for RL-ready code analysis scores."""

from __future__ import annotations

from schemas.response import ScoreBreakdown


class RewardService:
    """Compute reward scores from model, domain, lint, and complexity signals."""

    @staticmethod
    def _clamp_score(value: float) -> float:
        return round(max(0.01, min(0.99, float(value))), 4)

    def compute(self, *, ml_score: float, domain_score: float, lint_score: float, complexity_penalty: float) -> ScoreBreakdown:
        """Apply dynamic reward shaping based on quality, errors, and completion."""

        quality_signal = max(0.0, min(1.0, (0.45 * ml_score) + (0.3 * domain_score) + (0.25 * lint_score)))
        error_reduction_signal = max(0.0, min(1.0, lint_score - (0.6 * complexity_penalty)))
        completion_signal = max(0.0, min(1.0, (ml_score + domain_score + lint_score) / 3.0))
        reward = max(
            0.0,
            min(
                1.0,
                (0.35 * quality_signal)
                + (0.25 * completion_signal)
                + (0.2 * error_reduction_signal)
                + (0.1 * ml_score)
                + (0.1 * domain_score)
                - (0.15 * complexity_penalty),
            ),
        )
        return ScoreBreakdown(
            ml_score=self._clamp_score(ml_score),
            domain_score=self._clamp_score(domain_score),
            lint_score=self._clamp_score(lint_score),
            complexity_penalty=self._clamp_score(complexity_penalty),
            quality_signal=self._clamp_score(quality_signal),
            error_reduction_signal=self._clamp_score(error_reduction_signal),
            completion_signal=self._clamp_score(completion_signal),
            reward=self._clamp_score(reward),
        )