const listener = Deno.listen({ port: 8080 });

const decoder = new TextDecoder();
const encoder = new TextEncoder();

for await (const conn of listener) {
  handleConn(conn);
}

async function handleConn(conn: Deno.Conn) {
  const buf = new Uint8Array(1024);
  const bytes = await conn.read(buf);
  if (bytes === null) {
    conn.close();
    return;
  }

  const rawRequest = decoder.decode(buf.subarray(0, bytes));

  console.log(rawRequest);

  const [
    requestMethod,
    requestHost,
    requestUserAgent,
    requestAccept,
    requestContentType,
    requestContentLength,
    _,
    requestBody,
  ] = rawRequest.split("\r\n");

  const [method, path, protocol] = requestMethod.split(" ");
  const [, host] = requestHost.split(" ");
  const [, userAgent] = requestUserAgent.split(" ");
  const [, accept] = requestAccept.split(" ");
  const [, contentType] = requestContentType.split(" ");
  const [, contentLength] = requestContentLength.split(" ");

  const responseBody = `{` +
    `"method": "${method}",` +
    `"path": "${path}",` +
    `"protocol": "${protocol}",` +
    `"host": "${host}",` +
    `"user-agent": "${userAgent}",` +
    `"accept": "${accept}",` +
    `"content-type": "${contentType}",` +
    `"content-length": "${contentLength}",` +
    `"body": "${requestBody}"` +
    `}\n`;

  const response =
    "HTTP/1.1 200 OK\r\n" +
    "Content-Type: text/json\r\n" +
    `Content-Length: ${responseBody.length}\r\n` +
    "Connection: close\r\n" +
    "\r\n" +
    responseBody;

  await conn.write(encoder.encode(response));
  conn.close();
}