"""Feature engineering shared by training and serving. Keep this identical to api/app/services/scoring.py."""
import pandas as pd

IMPACT_ORDER = {"MODIFIER": 0, "LOW": 1, "MODERATE": 2, "HIGH": 3}
CATEGORICAL = ["consequence"]
NUMERIC = ["impact_rank", "gnomad_af", "cadd_phred", "am_pathogenicity"]


def build(df: pd.DataFrame) -> pd.DataFrame:
    out = pd.DataFrame()
    out["impact_rank"] = df["impact"].map(IMPACT_ORDER).fillna(0)
    out["gnomad_af"] = pd.to_numeric(df["gnomad_af"], errors="coerce").fillna(0.0)
    out["cadd_phred"] = pd.to_numeric(df["cadd_phred"], errors="coerce")
    out["am_pathogenicity"] = pd.to_numeric(df["am_pathogenicity"], errors="coerce")
    out["consequence"] = df["consequence"].astype("category")
    return out