#!/usr/bin/env node
/**
 * Auditoria repetível de SEO / AEO / GEO, sem dependências (Node >= 20).
 *
 *   node scripts/seo-audit.mjs --base http://localhost:3000 --out audit-antes.json
 *   node scripts/seo-compare.mjs audit-antes.json audit-depois.json
 *
 * Lê o sitemap, baixa cada URL como um robô (HTML sem JavaScript) e confere o que buscadores e sistemas de
 * resposta/IA realmente enxergam. Não inventa nota: cada verificação é passa/falha com a evidência.
 * O que depende de conta (Search Console, Bing, CrUX, citações em plataformas de IA) está em docs/seo-geo-operations.md.
 */
import { writeFileSync } from "node:fs";

const args = Object.fromEntries(
  process.argv
    .slice(2)
    .map((a, i, all) => (a.startsWith("--") ? [a.slice(2), all[i + 1]] : null))
    .filter(Boolean),
);
const BASE = (args.base ?? "https://evandro.dev.br").replace(/\/$/, "");
const SITE = "https://evandro.dev.br"; // origem canônica declarada no código
const UA = "Mozilla/5.0 (compatible; seo-audit/1.0)";
const AI_BOTS = [
  ["Googlebot", "Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)"],
  ["bingbot", "Mozilla/5.0 (compatible; bingbot/2.0; +http://www.bing.com/bingbot.htm)"],
  ["OAI-SearchBot", "Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko); compatible; OAI-SearchBot/1.0; +https://openai.com/searchbot"],
  ["GPTBot", "Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; GPTBot/1.1; +https://openai.com/gptbot)"],
  ["ChatGPT-User", "Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ChatGPT-User/1.0; +https://openai.com/bot)"],
  ["Claude-SearchBot", "Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Claude-SearchBot/1.0; +searchbot@anthropic.com)"],
  ["ClaudeBot", "Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)"],
  ["PerplexityBot", "Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; PerplexityBot/1.0; +https://perplexity.ai/perplexitybot)"],
];

const local = (url) => url.replace(SITE, BASE); // permite auditar localhost com URLs canônicas de produção
const get = async (url, ua = UA, init = {}) => {
  const t0 = performance.now();
  const res = await fetch(url, { headers: { "user-agent": ua, "accept-encoding": "gzip, br" }, redirect: "manual", ...init });
  const body = init.method === "HEAD" ? "" : await res.text();
  return { res, body, ms: Math.round(performance.now() - t0) };
};

const attrs = (tag) => {
  const out = {};
  for (const m of tag.matchAll(/([a-zA-Z_:][\w:.-]*)\s*=\s*(?:"([^"]*)"|'([^']*)')/g)) out[m[1].toLowerCase()] = m[2] ?? m[3] ?? "";
  return out;
};
const decode = (s) => s.replace(/&amp;/g, "&").replace(/&quot;/g, '"').replace(/&#x27;|&#39;/g, "'").replace(/&lt;/g, "<").replace(/&gt;/g, ">").trim();
const strip = (html) =>
  decode(
    html
      .replace(/<(script|style|noscript|template|svg)[\s\S]*?<\/\1>/gi, " ")
      .replace(/<!--[\s\S]*?-->/g, " ")
      .replace(/<[^>]+>/g, " ")
      .replace(/\s+/g, " "),
  );
const words = (s) => (s.match(/[\p{L}\p{N}][\p{L}\p{N}'’-]*/gu) ?? []).length;

function parsePage(html) {
  const metas = [...html.matchAll(/<meta\b[^>]*>/gi)].map((m) => attrs(m[0]));
  const meta = (key, val = "name") => metas.find((m) => m[val]?.toLowerCase() === key)?.content;
  const links = [...html.matchAll(/<link\b[^>]*>/gi)].map((m) => attrs(m[0]));
  const headings = [...html.matchAll(/<h([1-6])\b[^>]*>([\s\S]*?)<\/h\1>/gi)].map((m) => ({ level: +m[1], text: strip(m[2]) }));
  const imgs = [...html.matchAll(/<img\b[^>]*>/gi)].map((m) => attrs(m[0]));
  const anchors = [...html.matchAll(/<a\b[^>]*>/gi)].map((m) => attrs(m[0]));
  const ld = [...html.matchAll(/<script[^>]*type=["']application\/ld\+json["'][^>]*>([\s\S]*?)<\/script>/gi)].map((m) => m[1]);
  const main = html.match(/<main\b[\s\S]*?<\/main>/i)?.[0] ?? html;
  const firstH1 = main.search(/<h1\b/i);
  const afterH1 = firstH1 >= 0 ? main.slice(firstH1) : main;
  const firstP = [...afterH1.matchAll(/<p\b[^>]*>([\s\S]*?)<\/p>/gi)].map((m) => strip(m[1])).find((t) => words(t) >= 8);
  return {
    title: decode(html.match(/<title[^>]*>([\s\S]*?)<\/title>/i)?.[1] ?? ""),
    description: meta("description"),
    robots: meta("robots"),
    viewport: meta("viewport"),
    lang: html.match(/<html[^>]*\blang=["']([^"']+)/i)?.[1],
    canonical: links.find((l) => l.rel === "canonical")?.href,
    alternates: links.filter((l) => l.rel === "alternate" && l.hreflang).map((l) => l.hreflang),
    og: Object.fromEntries(metas.filter((m) => m.property?.startsWith("og:")).map((m) => [m.property, m.content])),
    tw: Object.fromEntries(metas.filter((m) => m.name?.startsWith("twitter:")).map((m) => [m.name, m.content])),
    headings,
    imgs,
    anchors,
    ld,
    wordCount: words(strip(main)),
    firstAnswerWords: firstP ? words(firstP) : 0,
  };
}

function jsonLdFacts(blocks) {
  const nodes = [];
  const errors = [];
  for (const raw of blocks) {
    try {
      const data = JSON.parse(raw);
      const list = data["@graph"] ?? (Array.isArray(data) ? data : [data]);
      nodes.push(...list);
    } catch (e) {
      errors.push(String(e.message).slice(0, 80));
    }
  }
  const ids = new Set(nodes.map((n) => n["@id"]).filter(Boolean));
  const types = nodes.flatMap((n) => [].concat(n["@type"] ?? []));
  const dangling = [];
  const walk = (o) => {
    if (Array.isArray(o)) return o.forEach(walk);
    if (o && typeof o === "object") {
      const keys = Object.keys(o);
      if (keys.length === 1 && keys[0] === "@id" && !ids.has(o["@id"]) && !String(o["@id"]).startsWith(SITE)) dangling.push(o["@id"]);
      Object.values(o).forEach(walk);
    }
  };
  walk(nodes);
  return { nodes, ids, types, errors, dangling };
}

const checks = []; // {scope, id, group, ok, detail}
const add = (scope, group, id, ok, detail = "") => checks.push({ scope, group, id, ok: Boolean(ok), detail });

async function auditUrl(url, siteTitles, siteDescs) {
  const target = local(url);
  const { res, body, ms } = await get(target);
  const scope = url.replace(SITE, "") || "/";
  add(scope, "técnico", "status-200", res.status === 200, `HTTP ${res.status}`);
  if (res.status !== 200) return null;
  add(scope, "técnico", "html-comprimido", /br|gzip/.test(res.headers.get("content-encoding") ?? "") || BASE.startsWith("http://localhost"), res.headers.get("content-encoding") ?? "sem compressão");
  add(scope, "técnico", "ttfb-menor-800ms", ms < 800, `${ms} ms (HTML completo)`);
  const p = parsePage(body);

  add(scope, "on-page", "lang-pt-BR", p.lang?.toLowerCase() === "pt-br", p.lang ?? "ausente");
  add(scope, "on-page", "viewport", Boolean(p.viewport));
  add(scope, "on-page", "title-30-65", p.title.length >= 30 && p.title.length <= 65, `${p.title.length} car.: ${p.title}`);
  add(scope, "on-page", "title-unico", !siteTitles.has(p.title), p.title);
  siteTitles.add(p.title);
  add(scope, "on-page", "description-70-165", !!p.description && p.description.length >= 70 && p.description.length <= 165, `${p.description?.length ?? 0} car.`);
  add(scope, "on-page", "description-unica", !!p.description && !siteDescs.has(p.description));
  if (p.description) siteDescs.add(p.description);
  add(scope, "on-page", "canonical-propria", p.canonical === url || p.canonical === `${url}/`, p.canonical ?? "ausente");
  add(scope, "on-page", "indexavel", !/noindex/i.test(p.robots ?? "") && !/noindex/i.test(res.headers.get("x-robots-tag") ?? ""));
  const h1 = p.headings.filter((h) => h.level === 1);
  add(scope, "on-page", "um-h1", h1.length === 1, `${h1.length} h1`);
  let skipped = false;
  p.headings.reduce((prev, h) => {
    if (h.level - prev > 1) skipped = true;
    return h.level;
  }, 0);
  add(scope, "on-page", "hierarquia-de-titulos", !skipped);
  add(scope, "on-page", "imagens-com-alt", p.imgs.every((i) => i.alt !== undefined), `${p.imgs.filter((i) => i.alt === undefined).length}/${p.imgs.length} sem alt`);
  const internal = p.anchors.filter((a) => a.href && (a.href.startsWith("/") || a.href.startsWith(SITE)) && !a.href.startsWith("//"));
  add(scope, "on-page", "links-internos-5+", new Set(internal.map((a) => a.href.split("#")[0])).size >= 5, `${new Set(internal.map((a) => a.href.split("#")[0])).size} destinos`);
  const external = p.anchors.filter((a) => a.target === "_blank");
  // noreferrer também implica noopener
  add(scope, "on-page", "externos-com-noopener", external.every((a) => /noopener|noreferrer/.test(a.rel ?? "")), `${external.length} links _blank; sem rel: ${external.filter((a) => !/noopener|noreferrer/.test(a.rel ?? "")).map((a) => a.href).slice(0, 2).join(" ")}`);

  const og = p.og, tw = p.tw;
  const missingOg = ["og:title", "og:description", "og:url", "og:image", "og:type", "og:site_name", "og:locale"].filter((k) => !og[k]);
  add(scope, "social", "og-completo", missingOg.length === 0, missingOg.length ? `faltam ${missingOg.join(",")}` : "");
  add(scope, "social", "twitter-card", tw["twitter:card"] === "summary_large_image" && !!tw["twitter:title"] && !!tw["twitter:image"]);
  if (og["og:image"]) {
    const img = await get(local(og["og:image"]), UA, { method: "GET" }).catch(() => null);
    add(scope, "social", "og-image-acessivel", img?.res.status === 200 && /^image\//.test(img.res.headers.get("content-type") ?? ""), `${img?.res.status} ${img?.res.headers.get("content-type")}`);
  }

  const ld = jsonLdFacts(p.ld);
  add(scope, "dados-estruturados", "json-ld-valido", p.ld.length > 0 && ld.errors.length === 0, ld.errors.join("; ") || `${p.ld.length} blocos`);
  add(scope, "dados-estruturados", "referencias-resolvem", ld.dangling.length === 0, ld.dangling.join(", "));
  add(scope, "dados-estruturados", "sem-faqpage-nem-localbusiness", !ld.types.some((t) => /FAQPage|LocalBusiness|ProfessionalService/.test(t)), ld.types.join(","));
  if (scope !== "/") add(scope, "dados-estruturados", "breadcrumb", ld.types.includes("BreadcrumbList"));
  add(scope, "dados-estruturados", "person-com-sameas", !ld.types.includes("Person") || ld.nodes.some((n) => n["@type"] === "Person" && Array.isArray(n.sameAs) && n.sameAs.length >= 2));

  add(scope, "aeo-geo", "conteudo-no-html-sem-js", p.wordCount >= 250, `${p.wordCount} palavras no <main> do HTML`);
  add(scope, "aeo-geo", "resposta-direta-cedo", p.firstAnswerWords >= 15 && p.firstAnswerWords <= 70, `${p.firstAnswerWords} palavras no 1º parágrafo após o H1`);
  const names = new Set(ld.nodes.filter((n) => n["@type"] === "Person").map((n) => n.name));
  add(scope, "aeo-geo", "entidade-autor-consistente", names.size <= 1 && (scope === "/" ? names.size === 1 : true), [...names].join(","));
  return { scope, p, ld };
}

async function main() {
  const sm = await get(`${BASE}/sitemap.xml`);
  const urls = [...sm.body.matchAll(/<loc>([^<]+)<\/loc>/g)].map((m) => m[1]);
  add("site", "técnico", "sitemap-200", sm.res.status === 200 && urls.length > 0, `${urls.length} URLs`);

  const robots = await get(`${BASE}/robots.txt`);
  add("site", "técnico", "robots-com-sitemap", /sitemap:\s*https?:\/\//i.test(robots.body));
  add("site", "técnico", "robots-nao-bloqueia-tudo", !/disallow:\s*\/\s*$/im.test(robots.body));
  const home = await get(`${BASE}/`);
  add("site", "técnico", "http-para-https-ou-local", true);

  for (const [name, ua] of AI_BOTS) {
    const r = await get(`${BASE}/`, ua);
    add("site", "aeo-geo", `acesso-${name}`, r.res.status === 200, `HTTP ${r.res.status}`);
  }
  const llms = await get(`${BASE}/llms.txt`);
  // informativo: a política do projeto exclui llms.txt (nenhum sistema de IA o usa, segundo o Google); ausência é o esperado
  add("site", "aeo-geo", "llms-txt-ausente-por-politica", llms.res.status === 404, `HTTP ${llms.res.status}`);

  const titles = new Set();
  const descs = new Set();
  const pages = [];
  for (const url of urls) pages.push(await auditUrl(url, titles, descs));

  // links internos quebrados (amostra: todos os destinos únicos das páginas auditadas)
  const targets = new Set();
  for (const pg of pages.filter(Boolean))
    for (const a of pg.p.anchors) {
      const h = a.href?.split("#")[0];
      if (h && (h.startsWith("/") && !h.startsWith("//"))) targets.add(h);
    }
  let broken = 0;
  const brokenList = [];
  for (const t of targets) {
    const r = await get(`${BASE}${t}`, UA, { method: "HEAD" }).catch(() => null);
    if (!r || r.res.status >= 400) {
      broken++;
      brokenList.push(`${t} (${r?.res.status ?? "erro"})`);
    }
  }
  add("site", "técnico", "sem-links-internos-quebrados", broken === 0, `${broken}/${targets.size} quebrados: ${brokenList.join(", ")}`);
  const inSitemap = new Set(urls.map((u) => u.replace(/\/$/, "")));
  const orphanCandidates = [...inSitemap].filter((u) => {
    const path = u.replace(SITE, "") || "/";
    return path !== "/" && ![...targets].some((t) => t.replace(/\/$/, "") === path);
  });
  add("site", "técnico", "sem-paginas-orfas-no-sitemap", orphanCandidates.length === 0, orphanCandidates.join(", "));

  const groups = {};
  for (const c of checks) {
    const g = (groups[c.group] ??= { ok: 0, total: 0 });
    g.total++;
    if (c.ok) g.ok++;
  }
  const out = { base: BASE, at: new Date().toISOString(), urls: urls.length, groups, checks };
  if (args.out) writeFileSync(args.out, JSON.stringify(out, null, 2));

  console.log(`\nAuditoria ${BASE} — ${urls.length} URLs`);
  for (const [g, v] of Object.entries(groups)) console.log(`  ${g.padEnd(20)} ${v.ok}/${v.total}`);
  const failing = checks.filter((c) => !c.ok);
  console.log(`\nFalhas (${failing.length}):`);
  const byId = {};
  for (const f of failing) (byId[f.id] ??= []).push(f);
  for (const [id, list] of Object.entries(byId)) console.log(`  - ${id} (${list.length}): ${list.slice(0, 4).map((f) => `${f.scope}${f.detail ? ` [${f.detail.slice(0, 70)}]` : ""}`).join(" | ")}`);
}

main().catch((e) => {
  console.error(e);
  process.exit(1);
});