"""Source adapters for AI Research Oracle."""

import json
import os
from abc import ABC, abstractmethod

# Centralized curation config (issue #7). One file, per-adapter blocks.
# Stdlib-only (JSON, not YAML) to honor Athena's dependency-free runtime.
_QUERIES_PATH = os.path.join(
    os.path.dirname(os.path.dirname(os.path.abspath(__file__))),
    "config", "queries.json")


def load_queries():
    """Load config/queries.json. Returns {'sources': {...}}.

    Safe fallback: if the file is missing/corrupt, returns an empty
    {'sources': {}} so adapters fall back to their class defaults
    (constructor None-override) instead of crashing the pipeline.
    """
    try:
        with open(_QUERIES_PATH) as f:
            data = json.load(f)
        return data if isinstance(data, dict) else {"sources": {}}
    except Exception:
        return {"sources": {}}


def source_config(name: str) -> dict:
    """Return the per-adapter block for `name`, or {} if absent."""
    return load_queries().get("sources", {}).get(name, {}) or {}


class SourceAdapter(ABC):
    """Base class for all ingestion adapters."""

    @abstractmethod
    def name(self) -> str:
        """Source name: 'github', 'arxiv', 'reddit'."""
        pass

    @abstractmethod
    def fetch(self, query: str = "", limit: int = 20) -> list[dict]:
        """Return entries matching DB schema fields."""
        pass