package proxy

import (
	"fmt"

	"github.com/gorilla/websocket"
)

type WebsocketReadWriter struct {
	W *websocket.Conn
}

func (w *WebsocketReadWriter) Read(p []byte) (int, error) {
	t, m, err := w.W.ReadMessage()
	if err != nil {
		return 0, fmt.Errorf("error reading websocket: %w", err)
	}
	if t != websocket.BinaryMessage {
		return 0, fmt.Errorf("error reading websocket: only binary messages are supported")
	}
	if cap(p) < len(m) {
		return 0, fmt.Errorf("error reading websocket: outputbuffer too short for input")
	}
	if i := copy(p, m); i != len(m) {
		return 0, fmt.Errorf("error reading websocket: copy failed %d of %d", i, len(m))
	}
	return len(m), nil
}

func (w *WebsocketReadWriter) Write(p []byte) (int, error) {
	if err := w.W.WriteMessage(websocket.BinaryMessage, p); err != nil {
		return 0, fmt.Errorf("error writing websocket: %w", err)
	}
	return len(p), nil
}

func (w *WebsocketReadWriter) Close() error {
	return w.W.Close()
}