"""Dataset-specific logic for the Text2SPARQL repair pipeline.

Handles loading dataset configs, KG profiles, and endpoint URLs.
All dataset-specific hacks remain inside this file.
"""

from __future__ import annotations

import json
import logging
from pathlib import Path

from .config import RuntimeConfig
from .models import DatasetConfig

logger = logging.getLogger(__name__)


def load_dataset_config(dataset_id: str, config: RuntimeConfig) -> DatasetConfig:
    """Load dataset configuration from the runtime config.

    Args:
        dataset_id: The dataset identifier URL.
        config: The runtime configuration containing dataset definitions.

    Returns:
        DatasetConfig for the requested dataset.

    Raises:
        ValueError: If dataset_id is not found in the config.
    """
    if dataset_id not in config.datasets:
        available = list(config.datasets.keys())
        raise ValueError(
            f"Unknown dataset_id: {dataset_id!r}. "
            f"Available datasets: {available}"
        )

    ds_raw = config.datasets[dataset_id]
    return DatasetConfig(
        dataset_id=dataset_id,
        endpoint_url=ds_raw["endpoint_url"],
        kg_profile_path=ds_raw.get("kg_profile_path", ""),
        default_prefixes=ds_raw.get("default_prefixes", {}),
        mode=ds_raw.get("mode", "dbpedia"),
    )


def load_kg_profile(dataset: DatasetConfig) -> dict:
    """Load the KG profile for a dataset.

    The KG profile contains entity labels, property labels, and class labels
    used for context building. Returns an empty profile structure if the
    profile file does not exist yet.

    Args:
        dataset: The dataset configuration.

    Returns:
        Dictionary with keys: entities, properties, classes.
    """
    empty_profile = {
        "entities": [],
        "properties": [],
        "classes": [],
        "metadata": {
            "dataset_id": dataset.dataset_id,
            "mode": dataset.mode,
        },
    }

    profile_path = Path(dataset.kg_profile_path)
    if not profile_path.exists():
        logger.warning(
            "KG profile not found at %s — using empty profile. "
            "Context building will rely on prefix hints only.",
            dataset.kg_profile_path,
        )
        return empty_profile

    try:
        with open(profile_path, "r") as f:
            profile = json.load(f)
        # Ensure required keys exist
        for key in ("entities", "properties", "classes"):
            if key not in profile:
                profile[key] = []
        return profile
    except (json.JSONDecodeError, OSError) as exc:
        logger.error("Failed to load KG profile from %s: %s", profile_path, exc)
        return empty_profile


def get_endpoint_url(dataset: DatasetConfig) -> str:
    """Get the SPARQL endpoint URL for a dataset.

    Args:
        dataset: The dataset configuration.

    Returns:
        The endpoint URL string.
    """
    return dataset.endpoint_url