const http = require("http");
const https = require("https");
const fs = require("fs");
const path = require("path");

const port = Number(process.env.PORT) || 18080;
const root = __dirname;
const apiOrigin = "https://qhse.cncecoa.com";
const mimeTypes = {
  ".html": "text/html; charset=utf-8",
  ".css": "text/css; charset=utf-8",
  ".js": "application/javascript; charset=utf-8",
  ".json": "application/json; charset=utf-8",
  ".pdf": "application/pdf",
  ".xlsx": "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"
};

function proxyApi(request, response) {
  const target = new URL(request.url, apiOrigin);
  const headers = { ...request.headers, host: target.host };
  delete headers.origin;
  delete headers.referer;

  const proxyRequest = https.request(target, {
    method: request.method,
    headers
  }, (proxyResponse) => {
    response.writeHead(proxyResponse.statusCode || 502, proxyResponse.headers);
    proxyResponse.pipe(response);
  });

  proxyRequest.on("error", (error) => {
    response.writeHead(502, { "Content-Type": "application/json; charset=utf-8" });
    response.end(JSON.stringify({ code: 0, message: `接口代理失败：${error.message}`, data: null }));
  });
  request.pipe(proxyRequest);
}

function serveStatic(request, response) {
  const requestPath = decodeURIComponent(new URL(request.url, "http://localhost").pathname);
  const relativePath = requestPath === "/" ? "indexV2.html" : requestPath.replace(/^\/+/, "");
  const filePath = path.resolve(root, relativePath);
  if (filePath !== root && !filePath.startsWith(`${root}${path.sep}`)) {
    response.writeHead(403);
    response.end("Forbidden");
    return;
  }

  fs.stat(filePath, (statError, stat) => {
    if (statError || !stat.isFile()) {
      response.writeHead(404, { "Content-Type": "text/plain; charset=utf-8" });
      response.end("Not Found");
      return;
    }
    response.writeHead(200, {
      "Content-Type": mimeTypes[path.extname(filePath).toLowerCase()] || "application/octet-stream",
      "Cache-Control": "no-cache"
    });
    fs.createReadStream(filePath).pipe(response);
  });
}

http.createServer((request, response) => {
  if (request.url.startsWith("/qhse_webapi/")) {
    proxyApi(request, response);
    return;
  }
  serveStatic(request, response);
}).listen(port, "127.0.0.1", () => {
  console.log(`数据治理看板：http://127.0.0.1:${port}/indexV2.html`);
});