const express = require("express");
const router = express.Router();
const fs = require("fs");
const path = require("path");

const lastFilesDir = "./public/upload/converted/";
const rawDir = "./public/upload/raw/";
const renderPageName = "invoice_sign";

const getMostRecentFile = (dir) => {
  const files = orderReccentFiles(dir);
  return files.length ? files[0] : undefined;
};

const orderReccentFiles = (dir) => {
  return fs
    .readdirSync(dir)
    .filter((file) => fs.lstatSync(path.join(dir, file)).isFile())
    .map((file) => ({ file, mtime: fs.lstatSync(path.join(dir, file)).mtime }))
    .sort((a, b) => b.mtime.getTime() - a.mtime.getTime());
};

const { PDFDocument } = require("pdf-lib");

const signDir = "./public/img/imza.png";
const signPDF = async (sourceFile) => {
  // Fetch PNG image
  const pngUrl = signDir;
  const pngImageBytes = fs.readFileSync(signDir);
  const pBytes = fs.readFileSync(rawDir + sourceFile);
  const pdfDoc = await PDFDocument.load(pBytes);

  // Embed the JPG image bytes and PNG image bytes
  const pngImage = await pdfDoc.embedPng(pngImageBytes);

  // Get the width/height of the PNG image scaled down to 50% of its original size
  const pngDims = pngImage.scale(0.1);

  // Add a blank page to the document
  const pages = pdfDoc.getPages();

  // Draw the PNG image near the lower right corner of the JPG image
  page = pages[0];
  page.drawImage(pngImage, {
    x: page.getWidth() / 2 - pngDims.width / 2 + 75,
    y: page.getHeight() / 2 - pngDims.height,
    width: pngDims.width,
    height: pngDims.height,
  });

  // Serialize the PDFDocument to bytes (a Uint8Array)
  const pdfBytes = await pdfDoc.save();
  fs.writeFileSync(lastFilesDir + sourceFile, await pdfDoc.save());
  return pdfBytes;
};

// load the page
router.get("/", function (req, res) {
  let lastFiles = [];
  if (!fs.existsSync(lastFilesDir)) {
    fs.mkdirSync(lastFilesDir);
  }
  // const dir = fs.opendirSync(lastFilesDir);
  let filesOrdered = orderReccentFiles(lastFilesDir);

  if (filesOrdered.length > 5) {
    for (let index = 5; index < filesOrdered.length; index++) {
      filePath = lastFilesDir + filesOrdered[index].file;
      fs.unlinkSync(filePath);
    }
  }
  filesOrdered = orderReccentFiles(lastFilesDir);
  for (file of filesOrdered) {
    lastFiles.push({ type: "f", name: file.file });
  }
  // lastFiles.push({ type: "f", name: getMostRecentFile(lastFilesDir).file });
  res.render(renderPageName, { lastFiles });
});
//Post the upload file
// For handling the upload request
router.post("/", function (req, res) {
  // When a file has been uploaded
  if (req.files && Object.keys(req.files).length !== 0) {
    // Uploaded path
    const uploadedFile = req.files.uploadFile;

    // Logging uploading file
    console.log(uploadedFile);

    // Upload path
    const uploadPath = rawDir;
    if (!fs.existsSync(uploadPath)) {
      fs.mkdirSync(uploadPath);
    }
    // To save the file using mv() function
    uploadedFile.mv(uploadPath + uploadedFile.name, function (err) {
      if (err) {
        console.log(err);
        res.send("Failed !!");
      }
      // res.send("Successfully Uploaded !!");
      else {
        signPDF(uploadedFile.name);
        res.redirect(renderPageName);
      }
    });
  } else res.send("No file uploaded !!");
});

// To handle the download file request
router.get("/download", function (req, res) {
  const downloadFile = lastFilesDir + req.query.downloadFile;
  console.log(downloadFile);
  res.download(downloadFile, function (err) {});
});
module.exports = router;