// Shared helpers for the site's own test scripts. Kept dependency-light
// (linkedom for HTML parsing is the one exception, since hand-rolling that
// with regexes is how a link checker grows its own bugs).
import { readFileSync, readdirSync, statSync } from "node:fs";
import { dirname, join, resolve } from "node:path";
import { fileURLToPath } from "node:url";
import { parseHTML } from "linkedom";

export const here = dirname(fileURLToPath(import.meta.url));
export const siteRoot = resolve(here, "..");
export const repoRoot = resolve(siteRoot, "..");
export const distDir = join(siteRoot, "dist");

export function requireDist() {
  try {
    statSync(distDir);
  } catch {
    throw new Error(
      `${distDir} does not exist — run "npm run build" in site/ before the tests`,
    );
  }
}

export function walkFiles(dir = distDir, extension = ".html") {
  const out = [];
  for (const entry of readdirSync(dir, { withFileTypes: true })) {
    const full = join(dir, entry.name);
    if (entry.isDirectory()) {
      out.push(...walkFiles(full, extension));
    } else if (entry.name.endsWith(extension)) {
      out.push(full);
    }
  }
  return out;
}

export function walkHtmlFiles(dir = distDir) {
  return walkFiles(dir, ".html");
}

export function loadDocument(path) {
  const html = readFileSync(path, "utf8");
  return parseHTML(html).document;
}

let failures = 0;
export function fail(message) {
  failures += 1;
  console.error(`FAIL: ${message}`);
}

export function report(name) {
  if (failures > 0) {
    console.error(`\n${name}: ${failures} failure(s)`);
    process.exit(1);
  }
  console.log(`${name}: ok`);
}