from typing import Optional
from fastapi import APIRouter, Form, HTTPException, status, Query, UploadFile, File

from .model import UploadedFileData
from src.uploaded_file.schema import UploadedFileDataCreate, UploadedFileDataUpdate, UploadedFileDataRead, UploadedFileDataPagination
from src.uploaded_file.service import get, get_all, create, update, delete

from src.database.service import CommonParameters, search_filter_sort_paginate
from src.database.core import DbSession
from src.auth.service import CurrentUser
from src.models import StandardResponse
from pathlib import Path
from uuid import uuid4
import os
from datetime import datetime

router = APIRouter()

@router.get("", response_model=StandardResponse[UploadedFileDataPagination])
async def get_uploaded_files(
    db_session: DbSession,
    common: CommonParameters,
    items_per_page: Optional[int] = Query(5),
    search: Optional[str] = Query(None),
):
    """Get all uploaded files pagination."""
    uploaded_files = await get_all(
        db_session=db_session,
        items_per_page=items_per_page,
        search=search,
        common=common,
    )
    # return
    return StandardResponse(
        data=uploaded_files,
        message="Data retrieved successfully",
    )


@router.get("/{uploaded_file_id}", response_model=StandardResponse[UploadedFileDataRead])
async def get_uploaded_file(db_session: DbSession, uploaded_file_id: str):
    uploaded_file = await get(db_session=db_session, uploaded_file_id=uploaded_file_id)
    if not uploaded_file:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="A data with this id does not exist.",
        )

    return StandardResponse(data=uploaded_file, message="Data retrieved successfully")


@router.post("", response_model=StandardResponse[UploadedFileDataRead])
async def create_uploaded_file(
    db_session: DbSession,
    current_user: CurrentUser,
    filename: Optional[str] = Form(None),
    file_content: str = Form(...),
    uploaded_file: UploadFile = File(...),
):
    """
    Accept an UploadFile along with the UploadedFileDataCreate payload.
    The file bytes and filename are attached to the input model if possible,
    and created_by is set from the current user.
    """
    file_read = await uploaded_file.read()

    file_name = filename or uploaded_file.filename
    file_size = len(file_read)
    file_type = uploaded_file.content_type
    try:
        uploaded_file.file.seek(0)
    except Exception:
        raise Exception("Could not process uploaded file.")
    
    safe_name = Path(file_name).name
    unique_name = f"{safe_name}"

    src_dir = Path(__file__).resolve().parent.parent

    timestamp = datetime.now().strftime("%Y%m%d%H%M%S")
    uploads_dir = src_dir / "uploads" / timestamp
    os.makedirs(str(uploads_dir), exist_ok=True)

    file_path = uploads_dir / unique_name
    file_path.write_bytes(file_read)

    relative_path = Path(timestamp) / unique_name
    file_location = relative_path.as_posix()
    file_url = f"/uploads/{file_location}"

    uploaded_file_in = UploadedFileDataCreate(
        filename=file_name,
        file_content=file_content,
        file_url=file_url,
        file_size=file_size,
        file_type=file_type,
        created_by=current_user.name,
    )
    
    uploaded_file_obj = await create(db_session=db_session, uploaded_file_in=uploaded_file_in)

    return StandardResponse(data=uploaded_file_obj, message="Data created successfully")


@router.put("/{uploaded_file_id}", response_model=StandardResponse[UploadedFileDataRead])
async def update_uploaded_file(
    db_session: DbSession,
    uploaded_file_id: str,
    uploaded_file_in: UploadedFileDataUpdate,
    current_user: CurrentUser,
):
    uploaded_file = await get(db_session=db_session, uploaded_file_id=uploaded_file_id)

    if not uploaded_file:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="A data with this id does not exist.",
        )
    uploaded_file_in.updated_by = current_user.name

    return StandardResponse(
        data=await update(
            db_session=db_session, uploaded_file=uploaded_file, uploaded_file_in=uploaded_file_in
        ),
        message="Data updated successfully",
    )


@router.delete("/{uploaded_file_id}", response_model=StandardResponse[UploadedFileDataRead])
async def delete_uploaded_file(db_session: DbSession, uploaded_file_id: str):
    uploaded_file = await get(db_session=db_session, uploaded_file_id=uploaded_file_id)

    if not uploaded_file:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=[{"msg": "A data with this id does not exist."}],
        )

    # Attempt to delete the file on disk if a file_url is present
    file_url = uploaded_file.file_url
    if file_url:
        try:
            # file_url is stored like "/uploads/<timestamp>/<filename>"
            src_dir = Path(__file__).resolve().parent.parent
            file_path = src_dir / Path(file_url.lstrip("/"))
            if file_path.exists():
                file_path.unlink()
                # try to remove the timestamp directory if it's empty
                try:
                    file_path.parent.rmdir()
                except OSError:
                    # not empty or cannot remove, ignore
                    pass
        except Exception as e:
            raise HTTPException(
                status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
                detail=f"Failed to delete file from disk: {str(e)}",
            )

    await delete(db_session=db_session, uploaded_file_id=uploaded_file_id)

    return StandardResponse(message="Data deleted successfully", data=uploaded_file)