#!/usr/bin/env node

const fs = require("fs");
const path = require("path");
const yaml = require("yaml");

const puppeteer = require("puppeteer");
const pug = require("pug");

function parseData(dataFilePath) {
  return yaml.parse(fs.readFileSync(dataFilePath, { encoding: "utf8" }));
}

function createHtml(pugFile, data, outputPath) {
  const rendered = pug.renderFile(pugFile, data);

  fs.writeFile(outputPath, rendered, (err) => {
    if (err) throw err;
  });
}

async function printPDF(url) {
  const browser = await puppeteer.launch({ headless: "new" });
  const page = await browser.newPage();
  await page.goto(url, { waitUntil: "networkidle0" });
  const pdf = await page.pdf({ format: "A4" });

  await browser.close();
  return pdf;
}

function exportToPdf(htmlFile, pdfPath) {
  url = `file://${path.resolve(htmlFile)}`;

  printPDF(url).then((pdf) => {
    fs.writeFile(pdfPath, pdf, (err) => {
      if (err) throw err;
    });
  });
}

function exportRenderToPdf(dataFilePath, templatePath, assetsPath, outputPath, outputBasename) {
  const data = parseData(dataFilePath);
  const htmlPath = path.join(outputPath, `${outputBasename}.html`);
  const pdfPath = path.join(outputPath, `${outputBasename}.pdf`);
  const newAssetsPath = path.join(outputPath, "assets");

  fs.mkdirSync(outputPath, { recursive: true });
  fs.mkdirSync(newAssetsPath, { recursive: true });
  fs.cpSync(assetsPath, newAssetsPath, { recursive: true });

  createHtml(templatePath, data, htmlPath);
  console.log(`Wrote HTML file to ${htmlPath}`);

  exportToPdf(htmlPath, pdfPath);
  console.log(`Wrote PDF file to ${pdfPath}`);
}

const [inputPath, templateName, variantName, outputPath] = process.argv.slice(2);
if (!inputPath || !templateName || !variantName || !outputPath) {
  console.error(
    `The script should be called like :\n${process.argv[1]} input_path template_name variant_name output_dir`
  );
  process.exit(1);
}

const inputDirName = inputPath.split(path.sep).at(-1);
const dataFilePath = path.join(inputPath, `${variantName}.yaml`);
const templatePath = path.join(inputPath, `${templateName}.pug`);
const assetsPath = path.join(inputPath, "assets");

exportRenderToPdf(dataFilePath, templatePath, assetsPath, outputPath, `${inputDirName}_${variantName}`);