"""Adapter: ruff check with idiom/simplification selectors → Finding[]."""
from __future__ import annotations

import json

from scripts.manifest import Finding


def _severity_for_idiom_rule(code: str) -> str:
    if not code:
        return "low"
    if code.startswith(("PLR", "C90", "B")):
        return "medium"
    return "low"


def parse_ruff_idiom_output(stdout: str) -> list[Finding]:
    try:
        payload = json.loads(stdout)
    except json.JSONDecodeError:
        return []
    if not isinstance(payload, list):
        return []
    out: list[Finding] = []
    for item in payload:
        loc = item.get("location") or {}
        end = item.get("end_location") or loc
        code = item.get("code", "")
        out.append(Finding(
            tool="ruff-idiom",
            rule_id=code,
            severity=_severity_for_idiom_rule(code),
            file=item.get("filename", ""),
            line=loc.get("row", 0),
            end_line=end.get("row", loc.get("row", 0)),
            message=item.get("message", ""),
        ))
    return out