#!/usr/bin/env python3
"""gxp_bulk_ingest.py

Bulk-ingest GxP PDF files into the GxP Vector DB.

Usage::
    python scripts/gxp_bulk_ingest.py [--dir PATH_TO_PDFS]

If no --dir given, defaults to scripts/gxp/ .

The script will:
1. Recursively scan the directory for *.pdf files.
2. For each file, run the PDF-Plumber extraction via GxPDocumentPreprocessingService.
3. Send the extracted result to GxPVectorDBService.construct_vector_db().

This bypasses the HTTP API layer and calls the internal services directly, so it must
be run in the project root (or ensure PYTHONPATH includes project root).
"""
# 표준 라이브러리
from pathlib import Path
import argparse
import sys
import os
from typing import Set

# 외부 라이브러리 (런타임에 없으면 requirements.txt 참고)
from langchain_openai import OpenAIEmbeddings

# Ensure backend path importable
ROOT = Path(__file__).resolve().parents[1]
BACKEND_PATH = ROOT / "backend"
sys.path.append(str(BACKEND_PATH))

# 내부 서비스 모듈
from engines.chatbot_gxp.service.GxPDocumentPreprocessingService import (
    GxPDocumentPreprocessingService,
)
from engines.chatbot_gxp.service.GxPVectorDBService import GxPVectorDBService


# ---------------------------------------------------------------------------
# 유틸리티
# ---------------------------------------------------------------------------


def ensure_ollama() -> None:
    """Ollama 서버가 동작 중인지 사전 확인한다.

    임베딩 테스트가 실패하면 즉시 종료한다.
    """

    try:
        _ = OpenAIEmbeddings().embed_query("ping")
    except Exception as exc:  # pylint: disable=broad-except
        print(
            "[!] Ollama 서버에 연결할 수 없습니다. 'ollama serve'가 실행 중인지 확인하세요.\n",
            f"    상세 오류: {exc}",
            sep="",
        )
        sys.exit(1)


def ingest_pdfs(
    pdf_dir: Path,
    *,
    skip_existing: bool = False,
    reindex_existing: bool = False,
) -> None:
    """디렉터리 내 PDF를 벡터 DB 에 일괄 인덱싱한다."""

    pre_service = GxPDocumentPreprocessingService()
    vec_service = GxPVectorDBService()

    # 기존 컬렉션 목록 캐싱
    existing_collections: Set[str] = {
        col["name"] for col in vec_service._list_collections()  # type: ignore
    }

    pdf_files = list(pdf_dir.rglob("*.pdf"))
    if not pdf_files:
        print(f"[!] No PDF files found in {pdf_dir}")
        return

    stats = {"indexed": 0, "skipped": 0, "failed": 0}

    for pdf_path in pdf_files:
        rel_path = pdf_path.relative_to(ROOT)
        print(f"[+] Processing {rel_path}")

        try:
            # 1단계: 전처리
            doc = pre_service.pdf_plumber_edms_document_text_extraction(str(pdf_path))

            # 2단계: 컬렉션 이름 계산 후 존재 여부 판단
            raw_name = f"gxp_{doc.get('plant', 'default')}_{doc.get('filename', 'document')}"
            collection_name = vec_service._sanitize_collection_name(raw_name)  # type: ignore

            if collection_name in existing_collections:
                if skip_existing:
                    print("    ↩︎ skip (already indexed)")
                    stats["skipped"] += 1
                    continue

                if reindex_existing:
                    print("    ℹ︎ collection exists → 삭제 후 재인덱싱")
                    vec_service.delete_collection(collection_name)
                    existing_collections.remove(collection_name)

            # 3단계: 벡터 DB 구축
            ok = vec_service.construct_vector_db(doc)
            if ok:
                print("    ✔ indexed")
                stats["indexed"] += 1
                existing_collections.add(collection_name)
            else:
                print("    ✖ service returned False")
                stats["failed"] += 1
        except Exception as exc:  # pylint: disable=broad-except
            print(f"    ✖ failed: {exc}")
            stats["failed"] += 1

    # 요약 통계 출력
    print("\n──────── 요약 통계 ────────")
    for k, v in stats.items():
        print(f"{k:8}: {v}")


def main() -> None:
    """엔트리 포인트"""

    parser = argparse.ArgumentParser(
        description="Bulk ingest GxP PDFs into Chroma vector DB",
    )

    parser.add_argument(
        "--dir",
        type=str,
        default=str(ROOT / "scripts" / "gxp"),
        help="Directory containing PDF files (default: scripts/gxp)",
    )

    excl = parser.add_mutually_exclusive_group()
    excl.add_argument(
        "--skip-existing",
        action="store_true",
        help="Skip PDFs whose collection already exists",
    )
    excl.add_argument(
        "--reindex",
        action="store_true",
        help="Delete existing collection then reindex",
    )

    args = parser.parse_args()

    pdf_dir = Path(args.dir).expanduser().resolve()
    if not pdf_dir.is_dir():
        print(f"Directory not found: {pdf_dir}")
        sys.exit(1)

    ensure_ollama()

    ingest_pdfs(
        pdf_dir,
        skip_existing=args.skip_existing,
        reindex_existing=args.reindex,
    )


if __name__ == "__main__":
    main()