"""OpenAPI parser — extracts ApiContract entities from OpenAPI YAML specifications."""

from __future__ import annotations

from pathlib import Path
from typing import Any

import yaml

from app.modules.design.domain.entities import ApiContract


class OpenapiParser:
    """Parse OpenAPI YAML file and return dict mapping entity type name to list of instances.

    Returns {'api_contracts': [ApiContract, ...]}
    """

    def parse(self, file_path: Path) -> dict[str, list[Any]]:
        try:
            with open(file_path, encoding="utf-8") as f:
                spec = yaml.safe_load(f)
        except Exception:
            return {}

        if not isinstance(spec, dict) or "paths" not in spec:
            return {}

        contracts: list[ApiContract] = []
        paths = spec["paths"]
        if not isinstance(paths, dict):
            return {}

        for path, path_item in paths.items():
            if not isinstance(path_item, dict):
                continue
            for method, operation in path_item.items():
                # Skip non-HTTP-method keys (e.g., 'parameters', 'summary')
                if method.lower() not in (
                    "get", "post", "put", "delete", "patch", "options", "head", "trace",
                ):
                    continue
                if not isinstance(operation, dict):
                    continue

                operation_id = operation.get("operationId", "")
                summary = operation.get("summary", "")

                doc_id = f"API-{operation_id or method.upper()}-{path}"

                contracts.append(ApiContract(
                    doc_id=doc_id,
                    path=path,
                    method=method.upper(),
                    operation_id=operation_id or "",
                    summary=summary or "",
                ))

        if not contracts:
            return {}

        return {"api_contracts": contracts}