Biwascheme from Emacs (with repl)

emacs-biwa.el

;; Initialize Biwascheme interpreter on frontend(browser) then send and receive expressions with websocket client
;; INSTALL websocket.el, LOAD this file and RUN interactive function `load-ws` from Emacs
;; ws-close to close server
;; send expression (e.g functions) to browser with `C-c C-s` ... Tip#  cursor should be on function name
(require 'websocket)
(require 'scheme)

(defun biwa-start ()
  (interactive)
  ;(load-file  "~/.emacs.d/websocket.el")
  (biwa-start-ws)
  (biwa-start-repl))


(defun biwa-hov ()
  (interactive)
  (buffer-substring-no-properties (mark) (point)))



(defun biwa-selct ()
  (interactive)
  (backward-up-list)
  (mark-sexp)
  (biwa-send-text (biwa-hov)))

(defun biwa-eval-last-sexp ()
  (interactive)
  (biwa-send-text (format "%S" (elisp--preceding-sexp))))


;(define-key lisp-mode-map [remap isearch-forward] 'selct)
(define-key scheme-mode-map "\C-c\C-s" #'biwa-selct)
(define-key scheme-mode-map "\C-c\C-e" #'biwa-eval-last-sexp)

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;  web socket
;;;;;;;;;;;;;;;;

(defvar biwa-global-proc nil)
(defvar biwa-ws-conn nil)
(defvar biwa-client nil)

(defun biwa-send-text (msg)
  (websocket-send-text biwa-client msg))

(defun biwa-ws-close ()
  (interactive)
  (websocket-server-close biwa-ws-conn))
  
(defun biwa-start-ws ()
  (interactive)
  (setq tls-checktrust nil)
  (when (>= (string-to-number (substring emacs-version 0 2)) 24)
    (message "Testing with wss://127.0.0.1/")
    (when (eq system-type 'windows-nt)
      (message "Windows users must have gnutls DLLs in the emacs bin directory."))
    (setq biwa-ws-conn (websocket-server
                    8001
                    :host "127.0.0.1"
                    :on-message (lambda (_ws frame)
				  (setf biwa-client _ws)
                                  (comint-output-filter biwa-global-proc (format " %s\n" (websocket-frame-payload frame)))
				  (comint-output-filter biwa-global-proc biwa-prompt)
				  (message "ws frame: %S" (websocket-frame-payload frame)))
                    :on-open (lambda (_websocket) (message "Client connection opened!"))
                    :on-close (lambda (_websocket)
                                (message "Websocket closed"))))))
   

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;  derive comint
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defun biwa-ccb ()
  (interactive)
  (let ((comint-buffer-maximum-size 0))
    (comint-truncate-buffer)))

;; let's bind the new command to a keycombo
(define-key comint-mode-map "\C-c\M-o" #'biwa-ccb)

(defconst biwa-prompt "Biwa> ")

(defun biwa-input-sender (proc input)
  (setf biwa-global-proc proc)
  (message input)
  (biwa-send-text input))

(define-derived-mode
    biwa-mode comint-mode "biwa"
    "Run a Biwa shell."
    :syntax-table js2-mode-syntax-table
    (setq comint-prompt-regexp (concat "^" (regexp-quote biwa-prompt)))
    (setq comint-input-sender 'biwa-input-sender)

    (unless (comint-check-proc (current-buffer))
      ;; Was cat, but on non-Unix platforms that might not exist, so
      ;; use hexl instead, Interactive Javascript Mode which is part of the Emacs distribution.
      (let ((fake-proc
             (condition-case nil
                 (start-process "biwa" (current-buffer) "hexl")
               (file-error (start-process "biwa" (current-buffer) "cat")))))
        (set-process-query-on-exit-flag fake-proc nil)
        ;; Add a silly header
        (insert "Interactive Biwa Mode\n")
        (set-marker
         (process-mark fake-proc) (point))
        (comint-output-filter fake-proc biwa-prompt))))

(defun biwa-start-repl ()
  (interactive)
  (let ((buffer (generate-new-buffer "*BIWA*")))
    (with-current-buffer buffer
      (funcall 'biwa-mode))
    (switch-to-buffer buffer)))
  ;(display-buffer buffer '(display-buffer-pop-up-frame . nil)))