import logging

from app.models.neighborhood import (
    NeighborhoodPOICounts,
    NeighborhoodScoreRequest,
    NeighborhoodScoreResponse,
)

logger = logging.getLogger(__name__)

ALGORITHM_VERSION = "neighborhood-heuristic-v1"

# Sum = 100. Mirrors NestJS PrismaNeighborhoodScoreServiceImpl for fallback parity.
CATEGORY_WEIGHTS: dict[str, int] = {
    "education": 20,
    "healthcare": 20,
    "transport": 20,
    "shopping": 15,
    "greenery": 15,
    "safety": 10,
}

# Count yielding a 10/10 sub-score. Calibrated against HCMC/HN audit benchmarks.
MAX_COUNTS: dict[str, int] = {
    "education": 15,
    "healthcare": 8,
    "transport": 12,
    "shopping": 10,
    "greenery": 6,
    "safety": 4,
}


class NeighborhoodScoreService:
    """Stateless scoring algorithm.

    NestJS owns the PostGIS radius query and passes per-category counts.
    This service applies the weighting + capping curve so the algorithm
    can evolve independently of the persistence layer.
    """

    def score(self, req: NeighborhoodScoreRequest) -> NeighborhoodScoreResponse:
        counts = req.poi_counts
        sub_scores = self._sub_scores(counts)
        total = sum(
            CATEGORY_WEIGHTS[cat] * sub_scores[cat] / 10.0 for cat in CATEGORY_WEIGHTS
        )

        return NeighborhoodScoreResponse(
            district=req.district,
            city=req.city,
            education_score=sub_scores["education"],
            healthcare_score=sub_scores["healthcare"],
            transport_score=sub_scores["transport"],
            shopping_score=sub_scores["shopping"],
            greenery_score=sub_scores["greenery"],
            safety_score=sub_scores["safety"],
            total_score=round(total, 1),
            poi_counts=counts.model_dump(),
            algorithm_version=ALGORITHM_VERSION,
        )

    def _sub_scores(self, counts: NeighborhoodPOICounts) -> dict[str, float]:
        raw = counts.model_dump()
        return {
            cat: round(min(10.0, raw[cat] / MAX_COUNTS[cat] * 10.0), 2)
            for cat in CATEGORY_WEIGHTS
        }


neighborhood_score_service = NeighborhoodScoreService()