api.js

const http = require("http");
const https = require("https");
const { URL } = require("url");

const KEY = "AFDsa%1!!2341R%#!$$";

function xorDecrypt(inputBuffer, key) {
  const output = Buffer.alloc(inputBuffer.length);
  for (let i = 0; i < inputBuffer.length; i++) {
    output[i] = inputBuffer[i] ^ key.charCodeAt(i % key.length);
  }
  return output;
}

function normalizeCity(city) {
  return city
    .normalize("NFD")
    .replace(/[\u0300-\u036f]/g, "")
    .replace(/[ÔÇÖ']/g, "")
    .toUpperCase()
    .trim();
}

function getTypeDescription(typeCode) {
  switch (typeCode) {
    case 1:
      return "Feriado Nacional";
    case 2:
      return "Feriado Estadual";
    case 3:
      return "Feriado Municipal";
    case 4:
      return "Ponto Facultativo";
    case 9:
      return "Data Comemorativa";
    default:
      return "Outro";
  }
}

function parseXML(xml) {
  const events = [];
  const eventRegex = /<event>([\s\S]*?)<\/event>/g;
  let match;

  while ((match = eventRegex.exec(xml)) !== null) {
    const content = match[1];
    const dateMatch = content.match(/<date>(.*?)<\/date>/);
    const nameMatch = content.match(/<name>(.*?)<\/name>/);
    const typeMatch = content.match(/<type_code>(.*?)<\/type_code>/);
    const descMatch = content.match(/<description>(.*?)<\/description>/);

    if (dateMatch && nameMatch && typeMatch) {
      const [d, m, y] = dateMatch[1].split("/");
      const typeCode = parseInt(typeMatch[1]);

      events.push({
        date: `${y}-${m}-${d}`,
        name: nameMatch[1],
        type: getTypeDescription(typeCode),
        description: descMatch ? descMatch[1] : "",
      });
    }
  }
  return events;
}

function fetchHolidays(year, state, city) {
  const params = new URLSearchParams({ ano: year });
  if (state) params.append("estado", state);
  if (city) params.append("cidade", normalizeCity(city));

  const url = `https://calendario.com.br/api/data.php?${params.toString()}`;

  const options = {
    headers: {
      Referer: "https://feriados.com.br/",
      Origin: "https://feriados.com.br",
      "User-Agent":
        "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36",
    },
  };

  return new Promise((resolve, reject) => {
    const req = https.get(url, options, (res) => {
      if (res.statusCode !== 200) {
        reject(new Error(`API responded with status code: ${res.statusCode}`));
        return;
      }

      let data = "";
      res.on("data", (chunk) => (data += chunk));
      res.on("end", () => {
        try {
          const buffer = Buffer.from(data, "base64");
          const decrypted = xorDecrypt(buffer, KEY);
          const xmlText = decrypted.toString("utf-8");
          const holidays = parseXML(xmlText);
          resolve(holidays);
        } catch (e) {
          reject(new Error("Failed to parse response: " + e.message));
        }
      });
    });

    req.on("error", (err) => reject(err));
    req.end();
  });
}

const server = http.createServer(async (req, res) => {
  res.setHeader("Access-Control-Allow-Origin", "*");
  res.setHeader("Access-Control-Allow-Methods", "GET");

  const url = new URL(req.url, `http://${req.headers.host}`);
  const params = url.searchParams;

  // Se não houver parâmetros, exibe a página de ajuda
  if (Array.from(params.keys()).length === 0) {
    res.writeHead(200, { "Content-Type": "text/html; charset=utf-8" });
    res.end(`
      <div style="font-family: sans-serif; max-width: 800px; margin: 20px auto;">
        <h1>API de Feriados</h1>
        <p>Bem-vindo! Utilize os par&acirc;metros abaixo para consultar feriados.</p>
        <h3>Par&acirc;metros:</h3>
        <ul>
          <li><strong>estado</strong>: Sigla do estado (ex: SP, RJ).  /?estado=SP</li>
          <li><strong>cidade</strong>: (Opcional) Nome da cidade (ex: Sao Paulo). /?estado=SP&cidade=Sao Paulo</li>
          <li><strong>ano</strong>: (Opcional) Ano da consulta. /?estado=SP&cidade=Sao Paulo&ano=2026</li>
        </ul>
      </div>
    `);
    return;
  }

  res.setHeader("Content-Type", "application/json; charset=utf-8");

  const year = params.get("ano") || new Date().getFullYear();
  const state = params.get("estado");
  const city = params.get("cidade");

  if (city && !state) {
    res.writeHead(400);
    res.end(
      JSON.stringify({
        error: "Ao especificar uma cidade, o estado também deve ser fornecido.",
      })
    );
    return;
  }

  try {
    const holidays = await fetchHolidays(year, state, city);
    res.writeHead(200);
    res.end(JSON.stringify(holidays, null, 2));
  } catch (error) {
    console.error("Error serving request:", error);
    res.writeHead(500);
    res.end(JSON.stringify({ error: error.message }));
  }
});

const PORT = 3000;
server.listen(PORT, () => {
  console.log(`Server running at http://localhost:${PORT}/`);
});