package wsjson

import (

"cdr.dev/slog/v3"

"github.com/coder/websocket"

)

// Stream is a two-way messaging interface over a WebSocket connection.

type Stream[R any, W any] struct {

conn *websocket.Conn

r *Decoder[R]

w *Encoder[W]

}

func NewStream[R any, W any](conn *websocket.Conn, readType, writeType websocket.MessageType, logger slog.Logger) *Stream[R, W] {

return &Stream[R, W]{

conn: conn,

r: NewDecoder[R](conn, readType, logger),

// We intentionally don't call `NewEncoder` because it calls `CloseRead`.

w: &Encoder[W]{conn: conn, typ: writeType},

}

}

// Chan returns a `chan` that you can read incoming messages from. The returned

// `chan` will be closed when the WebSocket connection is closed. If there is an

// error reading from the WebSocket or decoding a value the WebSocket will be

// closed.

//

// Safety: Chan must only be called once. Successive calls will panic.

func (s *Stream[R, W]) Chan() <-chan R {

return s.r.Chan()

}

func (s *Stream[R, W]) Send(v W) error {

return s.w.Encode(v)

}

func (s *Stream[R, W]) Close(c websocket.StatusCode) error {

return s.conn.Close(c, "")

}

func (s *Stream[R, W]) Drop() {

_ = s.conn.Close(websocket.StatusInternalError, "dropping connection")

}