// Runs the wasm benchmark modules off the main thread. The threaded (mt)
// variant spawns its pthread workers from here (nested workers).
'use strict';

const instances = {}; // variant -> { module, run }

async function getInstance(variant) {
  if (!instances[variant]) {
    importScripts(`dist/bench_${variant}.js`);
    const factory = variant === 'mt' ? createBenchMT : createBenchST;
    const module = await factory({
      // Loaded via importScripts, the module would otherwise resolve the
      // .wasm (and the script pthread workers re-load) relative to THIS
      // worker's URL — point both back into dist/.
      locateFile: (path) => 'dist/' + path,
      mainScriptUrlOrBlob: `dist/bench_${variant}.js`,
      print: (line) => postMessage({ type: 'log', line }),
      printErr: (line) => postMessage({ type: 'log', line: '[stderr] ' + line }),
    });
    instances[variant] = {
      module,
      run: module.cwrap('run_bench', 'number', ['number', 'number', 'number']),
    };
  }
  return instances[variant];
}

onmessage = async (e) => {
  const { id, variant, routine, n, threads } = e.data;
  try {
    const inst = await getInstance(variant);
    const t0 = performance.now();
    const gflops = inst.run(routine, n, threads);
    const seconds = (performance.now() - t0) / 1000;
    postMessage({ type: 'result', id, gflops, seconds });
  } catch (err) {
    postMessage({ type: 'error', id, message: String(err && err.message || err) });
  }
};