var PDFDocument = require("pdfkit");
var doc = new PDFDocument({ size: "A4", autoFirstPage: false });
var fs = require("fs");
var ets = [];
var height = 841.89;
var width = 595.28;
const offset = 4000;
for (var i = offset; i < 4 * 100 + offset; i++) {
   ets.push(i.toString());
}

//const barcode = require("barcode");
var bwipjs = require("bwip-js");
const margin = 40;

//A4: [595.28, 841.89],
// 28.29

function print(xo, yo, bc) {
   xo = xo + 40;
   yo = yo + 40;
   doc.fontSize(14);
   doc.text(
      "Bitte alle Felder leserlich ausfüllen. \nDie Nummer unten bitte auf ALLE \nBücher schreiben!!",
      xo,
      yo
   );
   doc.fontSize(16);
   yo += 45;

   var h = yo + 40;
   doc.moveTo(xo, h).lineTo(xo + 180, h);
   doc.text("Vorame", xo, h + 5);
   doc.stroke();

   h += 50;
   doc.moveTo(xo, h).lineTo(xo + 180, h);
   doc.text("Nachname", xo, h + 5);
   doc.stroke();

   h += 50;
   doc.moveTo(xo, h).lineTo(xo + 180, h);
   doc.text("Klasse", xo, h + 5);
   doc.stroke();

   h += 50;
   doc.moveTo(xo, h).lineTo(xo + 180, h);
   doc.text("Telefon", xo, h + 5);
   doc.stroke();

   h += 50;
   doc.moveTo(xo, h).lineTo(xo + 180, h);
   doc.text("E-Mail", xo, h + 5);
   doc.stroke();
   //doc.rect(xo, yo, ewidth, eheight);
   //doc.stroke();

   //return new Promise((resolve)=>{resolve()});
   //Barcode:

   var imagewidth = 240;
   var imageheight = 20;
   return new Promise((resolve, reject) => {
      bwipjs.toBuffer(
         {
            bcid: "code128",
            text: bc,
            scale: 1,
            height: imageheight,
            width: imagewidth,
            includetext: true,
            textxalign: "center",
            textsize: 15,
         },
         (err, png) => {
            if (err) return console.log(err);
            doc.image(png, xo + 23 - 40, h + 23, {
               height: 50,
               width: imagewidth,
            });
            resolve();
         }
      );
   });
}

function page(items, callback, index) {
   //bekommt ein array mit 12 ids
   doc.addPage({ margin: 0, size: "A4" });
   doc.moveTo(width / 2, 0).lineTo(width / 2, height);
   doc.stroke();
   doc.moveTo(0, height / 2).lineTo(width, height / 2);
   doc.stroke();
   var i = 0;
   var proms = [];
   if (i < items.length) {
      proms.push(print(0, 0, items[0]));
      i++;
   }

   if (i < items.length) {
      proms.push(print(width / 2, 0, items[1]));
      i++;
   }

   if (i < items.length) {
      proms.push(print(0, height / 2, items[2]));
      i++;
   }

   if (i < items.length) {
      proms.push(print(width / 2, height / 2, items[3]));
      i++;
   }

   Promise.all(proms).then(() => {
      callback(index + 4);
   });
}

function printpack(index) {
   if (index >= ets.length) {
      doc.pipe(fs.createWriteStream(__dirname + "/student_form.pdf"));
      doc.end();
      return;
   }
   var i = [];
   for (var g = 0; g < 4; g++) {
      if (index + g >= ets.length) break;
      i.push(ets[index + g]);
   }
   page(i, printpack, index);
}
printpack(0);