from __future__ import annotations

import os
import sys
from pathlib import Path

from dotenv import load_dotenv
from huggingface_hub import hf_hub_download


PROJECT_ROOT = Path(__file__).resolve().parents[1]
ADK_SRC = PROJECT_ROOT / "adk-python" / "src"
LOCAL_DATASET_DIR = PROJECT_ROOT / "data" / "processed"
RUNTIME_DATASET_DIR = PROJECT_ROOT / "data" / "_runtime_processed"


def _dataset_repo_id() -> str:
    return os.getenv("MEGUMIN_HF_DATASET_REPO_ID", "Junhoee/megumin-chat")


def _dataset_filename() -> str:
    return os.getenv("MEGUMIN_HF_DATASET_FILENAME", "megumin_qa_dataset.json")


def _index_filename() -> str:
    return os.getenv("MEGUMIN_FAISS_INDEX_FILENAME", "megumin_questions.faiss")


def _qa_index_filename() -> str:
    return os.getenv("MEGUMIN_FAISS_QA_INDEX_FILENAME", "megumin_question_answer.faiss")


def _metadata_filename() -> str:
    return os.getenv("MEGUMIN_FAISS_METADATA_FILENAME", "megumin_questions_meta.json")


def _fact_dataset_filename() -> str:
    return os.getenv("MEGUMIN_HF_FACT_DATASET_FILENAME", "namuwiki_qa.json")


def _fact_index_filename() -> str:
    return os.getenv("MEGUMIN_HF_FACT_INDEX_FILENAME", "namuwiki_questions.faiss")


def _fact_qa_index_filename() -> str:
    return os.getenv("MEGUMIN_HF_FACT_QA_INDEX_FILENAME", "namuwiki_question_answer.faiss")


def _fact_metadata_filename() -> str:
    return os.getenv("MEGUMIN_HF_FACT_METADATA_FILENAME", "namuwiki_questions_meta.json")


def bootstrap_environment() -> None:
    load_dotenv(PROJECT_ROOT / ".env", override=True)
    if ADK_SRC.exists():
        adk_src = str(ADK_SRC)
        if adk_src not in sys.path:
            sys.path.insert(0, adk_src)


def resolve_dataset_dir() -> Path:
    RUNTIME_DATASET_DIR.mkdir(parents=True, exist_ok=True)

    try:
        hf_token = os.getenv("HF_TOKEN") or None
        repo_id = _dataset_repo_id()
        artifact_names = (
            _dataset_filename(),
            _index_filename(),
            _qa_index_filename(),
            _metadata_filename(),
            _fact_dataset_filename(),
            _fact_index_filename(),
            _fact_qa_index_filename(),
            _fact_metadata_filename(),
        )
        for artifact_name in artifact_names:
            try:
                hf_hub_download(
                    repo_id=repo_id,
                    repo_type="dataset",
                    filename=artifact_name,
                    token=hf_token,
                    local_dir=str(RUNTIME_DATASET_DIR),
                )
            except Exception:
                if artifact_name not in {_dataset_filename(), _fact_dataset_filename()}:
                    continue
                raise
        return RUNTIME_DATASET_DIR
    except Exception:
        if LOCAL_DATASET_DIR.exists() and any(LOCAL_DATASET_DIR.glob("*.json")):
            return LOCAL_DATASET_DIR
        raise