Opcode = enum
  Cont = 0,                 ## Denotes a continuation frame.
  Text = 1,                 ## Denotes a text frame.
  Binary = 2,               ## Denotes a binary frame.
  Close = 8,                ## Denotes a connection close.
  Ping = 9,                 ## Denotes a ping.
  Pong = 10                  ## Denotes a pong.

ReadyState = enum
  Connecting = 0, Open = 1, Closing = 2, Closed = 3

WebSocket = ref object
  tcpSocket*: AsyncSocket
  version*: int
  key*: string
  protocol*: string
  readyState*: ReadyState
  masked*: bool

WebSocketClosedError = object of WebSocketError

WebSocketCreationError = object of WebSocketError

WebSocketError = object of IOError

WebSocketFailedUpgradeError = object of WebSocketError

WebSocketHandshakeError = object of WebSocketError

WebSocketPacketTypeError = object of WebSocketError

WebSocketProtocolMismatchError = object of WebSocketError

proc close(ws: WebSocket) {....raises: [Exception, ValueError], tags: [RootEffect,
    WriteIOEffect, ReadIOEffect, TimeEffect].}

proc decodeBase16(str: string): string {....raises: [], tags: [].}

proc encodeBase16(str: string): string {....raises: [], tags: [].}

proc handshake(ws: WebSocket; headers: HttpHeaders): owned(Future[void]) {.
    ...raises: [Exception], tags: [RootEffect].}

proc hangup(ws: WebSocket) {....raises: [WebSocketError], tags: [RootEffect].}

proc newWebSocket(req: Request; protocol: string = ""): Future[WebSocket] {.
    ...raises: [Exception, ValueError], tags: [RootEffect].}

proc newWebSocket(url: string; protocol: string): Future[WebSocket] {.
    ...raises: [Exception, ValueError],
    tags: [RootEffect, ReadIOEffect, TimeEffect].}

proc newWebSocket(url: string; protocols: seq[string] = @[]): Future[WebSocket] {.
    ...raises: [Exception, ValueError],
    tags: [RootEffect, ReadIOEffect, TimeEffect].}

proc ping(ws: WebSocket; data = ""): owned(Future[void]) {....raises: [Exception],
    tags: [RootEffect, WriteIOEffect, ReadIOEffect, TimeEffect].}

proc receiveBinaryPacket(ws: WebSocket): Future[seq[byte]] {.
    ...raises: [Exception, ValueError],
    tags: [RootEffect, WriteIOEffect, ReadIOEffect, TimeEffect].}

proc receivePacket(ws: WebSocket): Future[(Opcode, string)] {.
    ...raises: [Exception, ValueError], tags: [RootEffect].}

proc receiveStrPacket(ws: WebSocket): Future[string] {.
    ...raises: [Exception, ValueError],
    tags: [RootEffect, WriteIOEffect, ReadIOEffect, TimeEffect].}

proc send(ws: WebSocket; text: string; opcode = Opcode.Text): Future[void] {.
    ...raises: [Exception],
    tags: [RootEffect, WriteIOEffect, ReadIOEffect, TimeEffect].}

proc setupPings(ws: WebSocket; seconds: float) {.
    ...raises: [Exception, ValueError],
    tags: [RootEffect, WriteIOEffect, ReadIOEffect, TimeEffect].}

proc toSeq(hv: HttpHeaderValues): seq[string] {....raises: [], tags: [].}