"""Audit: INSERT %s-Platzhalter vs. Parameter-Anzahl in backend/."""

from __future__ import annotations

import ast
import re
from pathlib import Path

ROOT = Path(__file__).resolve().parents[1]


def _count_tuple_elements(node: ast.AST) -> int | None:
    if isinstance(node, ast.Tuple):
        return len(node.elts)
    if isinstance(node, ast.List):
        return len(node.elts)
    if isinstance(node, ast.Call) and isinstance(node.func, ast.Attribute):
        if node.func.attr in {"values", "keys"}:
            return None
    if isinstance(node, ast.BinOp) and isinstance(node.op, ast.Add):
        left = _count_tuple_elements(node.left)
        right = _count_tuple_elements(node.right)
        if left is not None and right is not None:
            return left + right
    if isinstance(node, ast.ListComp):
        return None
    return None


def audit_file(path: Path) -> list[str]:
    issues: list[str] = []
    try:
        tree = ast.parse(path.read_text(encoding="utf-8"), filename=str(path))
    except SyntaxError:
        return issues

    for node in ast.walk(tree):
        if not isinstance(node, ast.Call):
            continue
        func = node.func
        if not (
            isinstance(func, ast.Attribute)
            and func.attr == "execute"
            and isinstance(func.value, ast.Name)
            and func.value.id == "cur"
        ):
            continue
        if len(node.args) < 2:
            continue
        sql_node, params_node = node.args[0], node.args[1]
        sql = None
        if isinstance(sql_node, ast.Constant) and isinstance(sql_node.value, str):
            sql = sql_node.value
        elif isinstance(sql_node, ast.JoinedStr):
            continue
        if not sql or "INSERT" not in sql.upper():
            continue
        if "VALUES" not in sql.upper():
            continue
        ph = sql.count("%s")
        param_count = _count_tuple_elements(params_node)
        if param_count is None:
            continue
        if ph != param_count:
            rel = path.relative_to(ROOT)
            issues.append(
                f"{rel}:{node.lineno} INSERT placeholders={ph} params={param_count}"
            )
    return issues


def main() -> int:
    issues: list[str] = []
    for path in ROOT.rglob("*.py"):
        if "venv" in path.parts or "__pycache__" in path.parts:
            continue
        issues.extend(audit_file(path))
    if issues:
        print("MISMATCHES:")
        for issue in sorted(issues):
            print(issue)
        return 1
    print("OK: keine INSERT-Platzhalter-Mismatches gefunden (statisch prüfbar).")
    return 0


if __name__ == "__main__":
    raise SystemExit(main())