import base64
from io import BytesIO

from sqlalchemy.ext.asyncio import AsyncSession

from modules.fulfillment_base.barcodes_pdf_gen import BarcodePdfGenerator, BarcodeData
from modules.fulfillment_base.models import Product
from modules.fulfillment_base.repositories import ProductRepository
from modules.fulfillment_base.schemas.product import GetProductBarcodePdfRequest


class BarcodePrinterService:
    session: AsyncSession

    def __init__(self, session: AsyncSession):
        self.session = session

    async def generate_pdf(
        self, request: GetProductBarcodePdfRequest
    ) -> tuple[str, BytesIO]:
        product: Product = await ProductRepository(self.session).get_by_id(
            request.product_id
        )
        barcode_data: BarcodeData = {
            "barcode": request.barcode,
            "template": product.barcode_template,
            "product": product,
            "num_duplicates": request.quantity,
        }
        filename = f"{product.id}_barcode.pdf"

        size = product.barcode_template.size
        generator = BarcodePdfGenerator(size.width, size.height)
        return filename, generator.generate([barcode_data])

    async def generate_base64(
        self, request: GetProductBarcodePdfRequest
    ) -> tuple[str, str]:
        filename, pdf_buffer = await self.generate_pdf(request)
        base64_string = base64.b64encode(pdf_buffer.read()).decode("utf-8")
        return filename, base64_string