/**
 * A stand-in gateway that stays connected and answers printer provisioning,
 * for scripts/e2e-provision.sh.
 *
 * With TELEMETRY_AFTER_PROVISION=1 it also reports each provisioned printer
 * (running, then failed a few seconds later), so the console has something to
 * alert on.
 *
 * With REPORT_IDLE=<gateway-printer-id> it reports that printer idle on
 * connect, so the scheduler treats it as free. A `start_print` command is
 * accepted, the file is downloaded from its presigned URL and hashed (the
 * hash is appended to the frames file, never the URL), and the printer then
 * reports running and finished, like a real print that goes well.
 *
 * Needs FARM_ID in the environment (the hello must name the token's farm).
 *
 * Usage: bun scripts/fake-gateway-serve.ts <ws-url> <edge-jwt> <seconds> <frames-file> [refuse-access-code]
 *
 * Every provision_printer / remove_printer frame it receives is appended to
 * <frames-file> as one JSON line, so the script can prove the credential
 * arrived here. A provision whose access_code equals <refuse-access-code> is
 * answered as a failure, like a printer that rejected the login.
 */
import { appendFileSync } from "node:fs";

const [url, jwt, seconds, framesFile, refuseCode] = process.argv.slice(2);
if (!url || !jwt || !seconds || !framesFile) {
  console.error("usage: fake-gateway-serve.ts <ws-url> <edge-jwt> <seconds> <frames-file> [refuse-code]");
  process.exit(2);
}

const ws = new WebSocket(url, { headers: { authorization: `Bearer ${jwt}` } } as never);
ws.onerror = () => {
  console.error("socket error");
  process.exit(1);
};
ws.onopen = () => {
  // farm_id is required by the hello schema; the backend checks it against the token's farm.
  ws.send(JSON.stringify({ type: "hello", gateway_id: "fake-gw", farm_id: process.env.FARM_ID }));
  if (process.env.REPORT_IDLE) {
    ws.send(JSON.stringify({ type: "telemetry", printers: [{ printer_id: process.env.REPORT_IDLE, name: "Fake", state: "IDLE", percent: 0, print_error: 0 }] }));
  }
  console.log("ready");
};

async function printFile(message: { command_id: string; printer_id: string; command: { job_id: string; file_name: string; url: string } }) {
  const report = (state: string, percent: number) =>
    ws.send(JSON.stringify({ type: "telemetry", printers: [{ printer_id: message.printer_id, name: "Fake", state, percent, print_error: 0 }] }));
  const body = new Uint8Array(await (await fetch(message.command.url)).arrayBuffer());
  const digest = new Bun.CryptoHasher("sha256").update(body).digest("hex");
  appendFileSync(framesFile, JSON.stringify({ type: "downloaded", file_name: message.command.file_name, bytes: body.length, sha256: digest }) + "\n");
  report("RUNNING", 20);
  setTimeout(() => report("RUNNING", 60), 1500);
  setTimeout(() => report("FINISH", 100), 3000);
}
ws.onmessage = (event) => {
  const message = JSON.parse(String(event.data));
  if (message.type === "command" && message.command?.action === "start_print") {
    appendFileSync(framesFile, JSON.stringify({ type: "start_print", printer_id: message.printer_id, file_name: message.command.file_name, job_id: message.command.job_id }) + "\n");
    ws.send(JSON.stringify({ type: "command_result", command_id: message.command_id, ok: true }));
    void printFile(message);
    return;
  }
  if (message.type !== "provision_printer" && message.type !== "remove_printer") return;
  appendFileSync(framesFile, JSON.stringify(message) + "\n");
  if (message.type === "provision_printer" && process.env.TELEMETRY_AFTER_PROVISION === "1") {
    const id = message.printer.id;
    const report = (state: string) =>
      ws.send(JSON.stringify({ type: "telemetry", printers: [{ printer_id: id, name: message.printer.name, state, percent: 40, print_error: 0 }] }));
    setTimeout(() => report("RUNNING"), 1500);
    setTimeout(() => report("RUNNING"), 3000);
    setTimeout(() => report("FAILED"), 4500);
  }
  const refused = message.type === "provision_printer" && refuseCode && message.printer.access_code === refuseCode;
  ws.send(
    JSON.stringify({
      type: "command_result",
      command_id: message.request_id,
      ok: !refused,
      ...(refused ? { error: "could not connect to the printer: the access code was rejected" } : {}),
    }),
  );
};
setTimeout(() => process.exit(0), Number(seconds) * 1000);