add single-page pdf export

sites/shared/components/workbench/exporting/pdf-maker.mjs

@@ -1,4 +1,4 @@
-import PDFDocument from 'pdfkit/js/pdfkit.standalone'
+import { Pdf, mmToPoints } from './pdf.mjs'
 import SVGtoPDF from 'svg-to-pdfkit'
 import { logoPath } from 'shared/components/logos/freesewing.mjs'
 
@@ -8,11 +8,6 @@ const logoSvg = `<svg viewBox="0 0 25 25">
   <path d="${logoPath}" />
 </svg>`
 
-/**
- * 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
- * */
-const mmToPoints = 2.834645669291339
 const lineStart = 50
 /**
  * Freesewing's first explicit class?
@@ -58,7 +53,10 @@ export class PdfMaker {
     this.strings = strings
     this.cutLayouts = cutLayouts
 
-    this.initPdf()
+    this.pdf = Pdf({
+      size: this.pageSettings.size.toUpperCase(),
+      layout: this.pageSettings.orientation,
+    })
 
     this.margin = this.pageSettings.margin * mmToPoints // margin is in mm because it comes from us, so we convert it to points
     this.pageHeight = this.pdf.page.height - this.margin * 2 // this is in points because it comes from pdfKit
@@ -73,22 +71,6 @@ export class PdfMaker {
     this.svgHeight = this.rows * this.pageHeight
   }
 
-  /** create the pdf document */
-  initPdf() {
-    // instantiate with the correct size and orientation
-    this.pdf = new PDFDocument({
-      size: this.pageSettings.size.toUpperCase(),
-      layout: this.pageSettings.orientation,
-    })
-
-    // 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
-    this.buffers = []
-
-    // use a listener to add new data to our buffer storage
-    this.pdf.on('data', this.buffers.push.bind(this.buffers))
-  }
-
   /** make the pdf */
   async makePdf() {
     await this.generateCoverPage()
@@ -97,21 +79,8 @@ export class PdfMaker {
   }
 
   /** convert the pdf to a blob */
-  toBlob() {
-    return new Promise((resolve) => {
-      // have to do it this way so that the document flushes everything to buffers
-      this.pdf.on('end', () => {
-        // convert buffers to a blob
-        resolve(
-          new Blob(this.buffers, {
-            type: 'application/pdf',
-          })
-        )
-      })
-
-      // end the stream
-      this.pdf.end()
-    })
+  async toBlob() {
+    return this.pdf.toBlob()
   }
 
   /** generate the cover page for the pdf */