"""B03 파일 입력 FastAPI 라우터."""

import asyncio
import logging
from pathlib import Path
from uuid import UUID

from fastapi import APIRouter, File, UploadFile
from fastapi.responses import JSONResponse

from B03_FileInput.B03_FileInput_Engine import (
    resolve_upload_destination,
    save_upload_stream,
)
from B03_FileInput.B03_FileInput_Engine_Analyze import analyze_input_metadata
from B03_FileInput.B03_FileInput_Repository import (
    create_input_file,
    get_project_storage_relative_path,
)
from B03_FileInput.B03_FileInput_Schema import (
    FileUploadDescriptor,
    FileUploadResponse,
    UploadedFileResult,
)
from common_util.common_util_json import atomic_write_json
from common_util.common_util_storage import resolve_stored_project_path
from common_util.common_util_workflow import load_project_workflow
from config.config_db import get_db_pool
from config.config_system import UPLOAD_MAX_FILES

logger = logging.getLogger(__name__)
router = APIRouter(prefix="/api/projects", tags=["B03 File Input"])


@router.post("/{project_id}/files", response_model=FileUploadResponse)
async def upload_project_files(
    project_id: UUID,
    files: list[UploadFile] = File(...),
) -> FileUploadResponse | JSONResponse:
    """프로젝트 입력 파일을 저장·분석하고 DB 메타데이터를 기록한다."""
    if not files or len(files) > UPLOAD_MAX_FILES:
        return JSONResponse(
            status_code=400,
            content={
                "status": "error",
                "message": f"파일은 1~{UPLOAD_MAX_FILES}개까지 가능합니다.",
            },
        )

    filenames = [upload.filename or "" for upload in files]
    if len({filename.casefold() for filename in filenames}) != len(filenames):
        return JSONResponse(
            status_code=400,
            content={"status": "error", "message": "동일한 파일명을 중복 업로드할 수 없습니다."},
        )
    las_count = sum(Path(filename).suffix.lower() in {".las", ".laz"} for filename in filenames)
    if las_count != 1:
        return JSONResponse(
            status_code=400,
            content={
                "status": "error",
                "message": "LAS 또는 LAZ 파일을 정확히 1개 포함해야 합니다.",
            },
        )

    pool = get_db_pool()
    saved_paths: list[Path] = []
    try:
        results: list[UploadedFileResult] = []

        async with pool.acquire() as connection:
            stored_path = await get_project_storage_relative_path(connection, project_id)
            project_root = Path(resolve_stored_project_path(stored_path))

            await connection.begin()
            try:
                for upload in files:
                    preliminary = FileUploadDescriptor(
                        original_filename=upload.filename or "",
                        size_bytes=max(upload.size or 0, 1),
                    )
                    destination = resolve_upload_destination(project_root, preliminary)
                    written_bytes = await save_upload_stream(upload, destination)
                    saved_paths.append(destination)
                    descriptor = FileUploadDescriptor(
                        original_filename=preliminary.original_filename,
                        size_bytes=written_bytes,
                    )
                    metadata = await asyncio.to_thread(analyze_input_metadata, destination)
                    relative_path = destination.relative_to(project_root).as_posix()
                    file_type = destination.suffix.lower().lstrip(".")
                    crs_epsg = metadata.get("epsg")
                    input_file_id = await create_input_file(
                        connection,
                        project_id=project_id,
                        file_type=file_type,
                        original_filename=descriptor.original_filename,
                        relative_path=relative_path,
                        file_size_bytes=written_bytes,
                        upload_by=None,
                        crs_epsg=int(crs_epsg) if crs_epsg is not None else None,
                        metadata=metadata,
                    )
                    results.append(
                        UploadedFileResult(
                            input_file_id=input_file_id,
                            original_filename=descriptor.original_filename,
                            file_type=file_type,
                            relative_path=relative_path,
                            size_bytes=written_bytes,
                            metadata=metadata,
                        )
                    )
                await connection.commit()
            except Exception:
                await connection.rollback()
                raise

        stage_root = project_root / "B03_FileInput"
        atomic_write_json(
            stage_root / "metadata.json",
            {"project_id": str(project_id), "files": [result.model_dump() for result in results]},
        )
        workflow_path = project_root / "workflow.json"
        if not workflow_path.exists():
            atomic_write_json(workflow_path, load_project_workflow(project_root))
        return FileUploadResponse(project_id=str(project_id), files=results)
    except LookupError as exc:
        return JSONResponse(status_code=404, content={"status": "error", "message": str(exc)})
    except (OSError, ValueError) as exc:
        for saved_path in saved_paths:
            saved_path.unlink(missing_ok=True)
        return JSONResponse(status_code=400, content={"status": "error", "message": str(exc)})
    except Exception:
        for saved_path in saved_paths:
            saved_path.unlink(missing_ok=True)
        logger.exception("B03 파일 업로드 처리 실패: project_id=%s", project_id)
        return JSONResponse(
            status_code=500,
            content={"status": "error", "message": "파일 업로드 처리 중 오류가 발생했습니다."},
        )
    finally:
        for upload in files:
            await upload.close()