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.barcodes_pdf_gen.types import PdfBarcodeImageGenData
from modules.fulfillment_base.models import Product, DealProduct
from modules.fulfillment_base.repositories import (
    ProductRepository,
    DealProductRepository,
)
from modules.fulfillment_base.schemas.product import (
    GetProductBarcodePdfRequest,
    GetDealBarcodesPdfRequest,
)


class BarcodePrinterService:
    session: AsyncSession

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

    async def generate_product_pdf(
        self, request: GetProductBarcodePdfRequest
    ) -> tuple[str, BytesIO]:
        product: Product = await ProductRepository(self.session).get_by_id(
            request.product_id
        )
        if product.barcode_image:
            barcode_data: PdfBarcodeImageGenData = {
                "barcode_image_url": product.barcode_image.image_url,
                "num_duplicates": request.quantity,
            }
        else:
            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, await generator.generate([barcode_data])

    async def generate_product_base64(
        self, request: GetProductBarcodePdfRequest
    ) -> tuple[str, str]:
        filename, pdf_buffer = await self.generate_product_pdf(request)
        base64_string = base64.b64encode(pdf_buffer.read()).decode("utf-8")
        return filename, base64_string

    async def generate_deal_pdf(
        self, request: GetDealBarcodesPdfRequest
    ) -> tuple[str, BytesIO]:
        deal_product_repo = DealProductRepository(self.session)
        deal_products: list[DealProduct] = await deal_product_repo.get_all(
            request.deal_id
        )

        if len(deal_products) == 0:
            return "no_content.pdf", BytesIO()

        barcodes_data: list[BarcodeData | PdfBarcodeImageGenData] = []

        for deal_product in deal_products:
            if deal_product.product.barcode_image:
                barcode_data: PdfBarcodeImageGenData = {
                    "barcode_image_url": deal_product.product.barcode_image.image_url,
                    "num_duplicates": deal_product.quantity,
                }
                barcodes_data.append(barcode_data)
            elif len(deal_product.product.barcodes) > 0:
                barcode_data: BarcodeData = {
                    "barcode": deal_product.product.barcodes[0].barcode,
                    "template": deal_product.product.barcode_template,
                    "product": deal_product.product,
                    "num_duplicates": deal_product.quantity,
                }
                barcodes_data.append(barcode_data)

        size = deal_products[0].product.barcode_template.size
        generator = BarcodePdfGenerator(size.width, size.height)
        filename = "deal_barcodes.pdf"
        return filename, await generator.generate(barcodes_data)

    async def generate_deal_base64(
        self, request: GetDealBarcodesPdfRequest
    ) -> tuple[str, str]:
        filename, pdf_buffer = await self.generate_deal_pdf(request)
        base64_string = base64.b64encode(pdf_buffer.read()).decode("utf-8")
        return filename, base64_string