#!/usr/bin/env pwsh
# https://docs.sheetjs.com/docs/demos/net/server#worker-threads

$oldDir = Get-Location
$tempDir = Join-Path -Path $env:TEMP -ChildPath "sheetjs-worker"
if (Test-Path -Path $tempDir) { Remove-Item -Path $tempDir -Recurse -Force }
New-Item -ItemType Directory -Path $tempDir | Out-Null
Set-Location -Path $tempDir

'{ "type": "module" }' | Out-File -FilePath "package.json" -Encoding ASCII

@'
/* load the worker_threads module */
import { parentPort } from 'node:worker_threads';

/* load the SheetJS module and hook to FS */
import { set_fs, readFile, write } from 'xlsx';
import * as fs from 'fs';
set_fs(fs);

/* the server will send a message with the `path` field */
parentPort.on('message', (task) => {
  // read file
  const wb = readFile(task.path, { dense: true });
  // send back XLSX
  parentPort.postMessage(write(wb, { type: "buffer", bookType: "xlsx" }));
  // remove file
  fs.unlink(task.path, ()=>{});
});
'@ | Out-File -FilePath "worker.js" -Encoding ASCII

Invoke-WebRequest -Uri "https://docs.sheetjs.com/server/worker_pool.js" -OutFile "worker_pool.js"
Invoke-WebRequest -Uri "https://docs.sheetjs.com/pres.numbers" -OutFile "pres.numbers"

@'
/* load dependencies */
import os from 'node:os';
import process from 'node:process'
import express from 'express';
import formidable from 'formidable';

/* load worker pool */
import WorkerPool from './worker_pool.js';

const pool = new WorkerPool(os.cpus().length);
process.on("beforeExit", () => { pool.close(); })

/* create server */
const app = express();
app.post('/', (req, res, next) => {
  // parse body
  const form = formidable({});
  form.parse(req, (err, fields, files) => {
    // look for "upload" field
    if(err) return next(err);
    if(!files["upload"]) return next(new Error("missing `upload` file"));

    // send a message to the worker with the path to the uploaded file
    pool.runTask({ path: files["upload"].filepath }, (err, result) => {
      if(err) return next(err);
      // send the file back as an attachment
      res.attachment("SheetJSPool.xlsx");
      res.status(200).end(result);
    });
  });
});

// start server
app.listen(7262, () => { console.log(`Example app listening on port 7262`); });
'@ | Out-File -FilePath "main.mjs" -Encoding ASCII

npm i --save https://cdn.sheetjs.com/xlsx-latest/xlsx-latest.tgz formidable@2.1.2

$expressVersions = @("4.21.2", "5.1.0")
foreach ($express in $expressVersions) {
  npm i --save express@$express
  npm ls | Select-String "express"
  # Test with different node versions (if available)
  $nodeVersions = @(20, 22, 24)
  foreach ($n in $nodeVersions) {
    nvm use $n
    node --version

    $proc = Start-Process -NoNewWindow -FilePath "node" -ArgumentList "main.mjs" -PassThru
    Start-Sleep -Seconds 2
    pwsh -NonInteractive -Command 'Invoke-WebRequest -Uri "http://localhost:7262/" -Method Post -Form @{ upload = Get-Item "pres.numbers" } -OutFile "SheetJSPool.xlsx"'

    npx -y xlsx-cli SheetJSPool.xlsx | Select-Object -First 10
    Remove-Item -Path "SheetJSPool.xlsx" -Force

    $proc | Stop-Process
  }
}

Set-Location $oldDir
Remove-Item -Path $tempDir -Recurse -Force