// OTA command senders. The firmware listens on the WebSocket for two-byte
// binary frames [FIRMWARE_UPDATE_CMD_HEAD, cmd_id] (see command_interface.h
// in the firmware). The dispatch is currently commented out in
// websocket_server.cpp — uncomment it on the firmware side to make these flow.
//
// Per the firmware retarget choice, the S3 build reuses the P4 enum slots:
//   0x00 = REQUEST_AVAILABLE_UPDATES
//   0x02 = START_UPDATE (S3 firmware)
//   0x03 = START_UPDATE (S3 webinterface)
import { $websocket } from "../WebSocketAtom";

const FIRMWARE_UPDATE_CMD_HEAD = 0xBB;

const FIRMWARE_UPDATE_CMD_REQUEST_AVAILABLE_UPDATES = 0x00;
const FIRMWARE_UPDATE_CMD_START_UPDATE_S3_FIRMWARE = 0x02;       // reused P4 slot
const FIRMWARE_UPDATE_CMD_START_UPDATE_S3_WEBINTERFACE = 0x03;   // reused P4 slot

function wsOpen(): WebSocket | null {
  const ws = $websocket.get();
  return ws && (ws as WebSocket).readyState === WebSocket.OPEN ? (ws as WebSocket) : null;
}

function sendFwCommand(cmdId: number): boolean {
  const ws = wsOpen();
  if (!ws) {
    console.error("[OTA] WS not open, cannot send command", cmdId);
    return false;
  }
  ws.send(new Uint8Array([FIRMWARE_UPDATE_CMD_HEAD, cmdId]));
  return true;
}

export function request_available_updates(): boolean {
  return sendFwCommand(FIRMWARE_UPDATE_CMD_REQUEST_AVAILABLE_UPDATES);
}

export function start_firmware_update_s3_fw(): boolean {
  return sendFwCommand(FIRMWARE_UPDATE_CMD_START_UPDATE_S3_FIRMWARE);
}

export function start_firmware_update_s3_web(): boolean {
  return sendFwCommand(FIRMWARE_UPDATE_CMD_START_UPDATE_S3_WEBINTERFACE);
}

// Sent on WS open so the firmware updates its currentVersion for the
// LittleFS image. The bundled web app is the source of truth for this
// version (LITTLEFS_VERSION in AppProviderStore.tsx).
export function send_webinterface_version(version: string): boolean {
  const ws = wsOpen();
  if (!ws) return false;
  ws.send(JSON.stringify({ message_type: "set_webinterface_version", version }));
  return true;
}