//  __SDEFILE__ - This file is a dependency for the stand-alone environment
import PDFDocument from 'pdfkit/js/pdfkit.standalone'

/**
 * PdfKit, the library we're using for pdf generation, uses points as a unit, so when we tell it things like where to put the svg and how big the svg is, we need those numbers to be in points
 * The svg uses mm internally, so when we do spatial reasoning inside the svg, we need to know values in mm
 * */
export const mmToPoints = 2.834645669291339

/**
 * A PDFKit Pdf with a few of our utilities included
 * @returns
 */
export const Pdf = ({ size, layout }) => {
  const pdf = new PDFDocument({
    size,
    layout,
  })

  // PdfKit wants to flush the buffer on each new page.
  // We can't save directly from inside a worker, so we have to manage the buffers ourselves so we can return a blob
  const buffers = []

  // use a listener to add new data to our buffer storage
  pdf.on('data', buffers.push.bind(buffers))

  /** convert the pdf to a blob */
  pdf.toBlob = function () {
    return new Promise((resolve) => {
      // have to do it this way so that the document flushes everything to buffers
      pdf.on('end', () => {
        // convert buffers to a blob
        resolve(
          new Blob(buffers, {
            type: 'application/pdf',
          })
        )
      })

      // end the stream
      pdf.end()
    })
  }

  return pdf
}