// Throughput and peak RSS over a JSON array of sources, one tool per process.
// Usage: node bench/throughput.mjs <inputs.json> [tool-substring] [--mode=downlevel]
import fs from "node:fs";
import { execFileSync } from "node:child_process";
import { tools } from "./tools.mjs";

const [inputsPath, only] = process.argv.slice(2).filter((a) => !a.startsWith("--"));
const mode = process.argv.find((a) => a.startsWith("--mode="))?.slice(7) ?? "erase";

if (process.env.TP_WORKER) {
  const inputs = JSON.parse(fs.readFileSync(inputsPath, "utf8"));
  const tool = tools[process.env.TP_WORKER];
  let strip = await tool.load();
  if (mode === "downlevel" && tool.downlevel) strip = await tool.downlevel();
  const bytes = inputs.reduce((n, s) => n + Buffer.byteLength(s), 0);
  let failed = 0;
  const pass = () => { failed = 0; for (const s of inputs) { try { strip(s); } catch { failed++; } } };
  // maxRSS already peaked while parsing the inputs, so sample current RSS per file instead.
  globalThis.gc();
  const before = process.memoryUsage.rss();
  let peak = before;
  for (const s of inputs) { try { strip(s); } catch {} const r = process.memoryUsage.rss(); if (r > peak) peak = r; }
  const times = [];
  for (let i = 0; i < 3; i++) { const t = performance.now(); pass(); times.push(performance.now() - t); }
  const ms = times.sort((a, b) => a - b)[1];
  console.log(JSON.stringify({ mbps: bytes / 1e6 / (ms / 1000), peakDeltaMiB: (peak - before) / 1048576, failed, files: inputs.length, mb: bytes / 1e6 }));
  process.exit(0);
}

console.log(`mode ${mode}, inputs ${inputsPath}\n`);
console.log("| tool | MB/s | peak RSS growth (first pass, sampled per file) | inputs that threw |");
console.log("|---|---|---|---|");
// TP_REVERSE lets a caller alternate tool order across repeated runs, same reason as
// bench/metrics.mjs's METRICS_REVERSE.
const order = process.env.TP_REVERSE ? Object.entries(tools).reverse() : Object.entries(tools);
for (const [name, tool] of order) {
  if (only && !name.includes(only)) continue;
  if (mode === "downlevel" && !tool.lowers) continue;
  const r = JSON.parse(execFileSync(process.execPath, ["--no-warnings", "--expose-gc", import.meta.filename, ...process.argv.slice(2)], { env: { ...process.env, TP_WORKER: name }, maxBuffer: 1 << 24 }).toString().trim().split("\n").pop());
  console.log(`| ${name} | ${r.mbps.toFixed(1)} | +${r.peakDeltaMiB.toFixed(1)}MiB | ${r.failed}/${r.files} (${r.mb.toFixed(1)}MB total) |`);
}