vendor_and_build_docs.js

const Path = require("path");
const Fs = require("fs");
const Cp = require("child_process");

const deleteFolderRecursive = (path) => {
  if (Fs.existsSync(path)) {
    Fs.readdirSync(path).forEach((file, index) => {
      const curPath = Path.join(path, file);
      if (Fs.lstatSync(curPath).isDirectory()) {
        // recurse
        deleteFolderRecursive(curPath);
      } else {
        // delete file
        Fs.unlinkSync(curPath);
      }
    });
    Fs.rmdirSync(path);
  }
};

function copyFileSync(source, target) {
  var targetFile = target;

  //if target is a directory a new file with the same name will be created
  if (Fs.existsSync(target)) {
    if (Fs.lstatSync(target).isDirectory()) {
      targetFile = Path.join(target, Path.basename(source));
    }
  }

  Fs.writeFileSync(targetFile, Fs.readFileSync(source));
}

function copyFolderRecursiveSync(source, target) {
  var files = [];

  //check if folder needs to be created or integrated
  var targetFolder = Path.join(target, Path.basename(source));
  if (!Fs.existsSync(targetFolder)) {
    Fs.mkdirSync(targetFolder);
  }

  //copy
  if (Fs.lstatSync(source).isDirectory()) {
    files = Fs.readdirSync(source);
    files.forEach(function (file) {
      var curSource = Path.join(source, file);
      if (Fs.lstatSync(curSource).isDirectory()) {
        copyFolderRecursiveSync(curSource, targetFolder);
      } else {
        copyFileSync(curSource, targetFolder);
      }
    });
  }
}

// Get the source installation.json to get source paths
const installationJson = Fs.readFileSync(
  Path.resolve("_esy/default/installation.json")
);

// Remove version numbers to make it easier to query the file
const cleanedInstallationJson = installationJson
  .toString()
  .replace(/@(opam:)?[a-z0-9\.]+@[0-9a-z]+/g, "");

// Parse the cleaned JSON
const packageIndex = JSON.parse(cleanedInstallationJson);

const vendorPackages = (packages) => {
  // Create vendor folder
  try {
    Fs.mkdirSync("vendor");
  } catch (e) {
    console.warn(e);
  }

  // Copy the wanted packages into place
  packages.forEach(({ package, target, extra }) => {
    const vendorPath = Path.join("vendor", target);
    try {
      Fs.mkdirSync(vendorPath);
    } catch (e) {
      console.warn(e);
    }

    try {
      copyFolderRecursiveSync(packageIndex[package], vendorPath);
    } catch (e) {
      console.warn(e);
    }

    // Extra steps needed
    if (extra != null) {
      try {
        extra(Path.join(vendorPath, Path.basename(packageIndex[package])));
      } catch (e) {
        console.warn(e);
      }
    }
  });
};

// The packages we want with potential extra steps needed
const wantedPackages = [
  { package: "@reason-native-web/piaf", target: "piaf" },
  {
    package: "@opam/hmap",
    target: "hmap",
    extra: (path) => {
      const duneFile = "(library (name hmap) (public_name hmap))";
      const duneProject = "(lang dune 1.11)";

      Fs.writeFileSync(Path.join(path, "src", "dune"), duneFile);
      Fs.writeFileSync(Path.join(path, "dune-project"), duneProject);
      Fs.copyFileSync(Path.join(path, "opam"), Path.join(path, "hmap.opam"));
    },
  },
];

// Vendor packages
vendorPackages(wantedPackages);

// Generate docs
Cp.execSync("esy docs");

// Print path to allow `open $(node vendor_and_build_docs.js)`
console.log(Cp.execSync("esy docs-path").toString().trim() + "/index.html");

// Cleanup
deleteFolderRecursive("vendor");