Stirling-PDF/functions/splitPDF.js

import { PDFDocument, ParseSpeeds } from 'pdf-lib'
import { createSubDocument } from "./extractPages.js";

export const splitPDF = async (snapshot, splitAfterPageArray) => {
    const pdfDoc = await PDFDocument.load(snapshot)

    const numberOfPages = pdfDoc.getPages().length;

    let pagesArray = [];
    let splitAfter = splitAfterPageArray.shift();
    const subDocuments = [];

    for (let i = 0; i < numberOfPages; i++) {
        if(i > splitAfter && pagesArray.length > 0) {
            subDocuments.push(await createSubDocument(pdfDoc, pagesArray));
            splitAfter = splitAfterPageArray.shift();
            pagesArray = [];
        }
        pagesArray.push(i);        
    }
    subDocuments.push(await createSubDocument(pdfDoc, pagesArray));
    pagesArray = [];

    return subDocuments;
};