+;;; lurk.el --- Little Unified iRc Klient -*- lexical-binding:t -*-
+
+;; Copyright (C) 2021 Tim Vaughan
+
+;; Author: Tim Vaughan <timv@ughan.xyz>
+;; Created: 14 June 2021
+;; Version: 1.0
+;; Keywords: network
+;; Homepage: http://thelambdalab.xyz/erc
+;; Package-Requires: ((emacs "26"))
+
+;; This file is not part of GNU Emacs.
+
+;; This program is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this file. If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;;; Code:
+
+(provide 'lurk)
+
+
+;;; Customizations
+;;
+
+(defgroup lurk nil
+ "Little Unified iRc Klient."
+ :group 'network)
+
+(defcustom lurk-nick "plugd"
+ "Default nick.")
+(defcustom lurk-full-name "plugd"
+ "Default full name.")
+(defcustom lurk-user-name "plugd"
+ "Default user name.")
+
+(defcustom lurk-networks
+ '(("libera" "irc.libera.chat" 6697)
+ ("freenode" "chat.freenode.net" 6697)
+ ("local" "localhost" 6697))
+ "IRC networks.")
+
+(defcustom lurk-allow-ipv6 nil
+ "Set to non-nil to allow use of IPv6.")
+
+;;; Faces
+;;
+
+(defface lurk-text
+ '((t :inherit font-lock-preprocessor-face))
+ "Face used for Lurk text.")
+
+(defface lurk-your-nick
+ '((t :inherit font-lock-constant-face))
+ "Face used for highlighting your nick.")
+
+(defface lurk-prompt
+ '((t :inherit org-level-2))
+ "Face used for the prompt.")
+
+(defface lurk-context
+ '((t :inherit org-list-dt))
+ "Face used for the context name in the prompt.")
+
+(defface lurk-faded
+ '((t :inherit font-lock-preprocessor-face))
+ "Face used for faded Lurk text.")
+
+(defface lurk-bold
+ '((t :inherit font-lock-function-name-face))
+ "Face used for bold Lurk text.")
+
+(defface lurk-error
+ '((t :inherit font-lock-regexp-grouping-construct))
+ "Face used for Lurk error text.")
+
+;;; Global variables
+;;
+
+(defvar lurk-version "Lurk v0.1")
+
+(defvar lurk-notice-prefix
+ (concat
+ (propertize
+ "-" 'face 'lurk-faded)
+ (propertize
+ "!" 'face 'lurk-bold)
+ (propertize
+ "-" 'face 'lurk-faded)))
+
+(defvar lurk-error-prefix
+ (propertize "!!!" 'face 'lurk-error))
+
+
+(defvar lurk-prompt-string
+ (propertize "> " 'face 'lurk-prompt))
+
+
+;;; Network process
+;;
+
+(defvar lurk-response "")
+
+(defun lurk-filter (proc string)
+ (dolist (line (split-string (concat lurk-response string) "\n"))
+ (if (string-suffix-p "\r" line)
+ (lurk-eval-msg-string (string-trim line))
+ (setq lurk-response line))))
+
+(defun lurk-sentinel (proc string)
+ (unless (equal "open" (string-trim string))
+ (lurk-display-error "Disconnected from server.")
+ (clrhash lurk-contexts)
+ (setq lurk-current-context nil)
+ (lurk-render-prompt)
+ (cancel-timer lurk-ping-timer)))
+
+(defun lurk-start-process (network)
+ (let* ((row (assoc network lurk-networks))
+ (host (elt row 1))
+ (port (elt row 2))
+ (flags (seq-drop row 3)))
+ (make-network-process :name "lurk"
+ :host host
+ :service port
+ :family (if lurk-allow-ipv6 nil 'ipv4)
+ :filter #'lurk-filter
+ :sentinel #'lurk-sentinel
+ :nowait nil
+ :tls-parameters (if (memq :notls flags)
+ nil
+ (cons 'gnutls-x509pki
+ (gnutls-boot-parameters
+ :type 'gnutls-x509pki
+ :hostname host)))
+ :buffer "*lurk*")))
+
+(defvar lurk-ping-timer nil)
+(defvar lurk-ping-period 60)
+
+(defun lurk-ping-function ()
+ (lurk-send-msg (lurk-msg nil nil "PING" (car (process-contact (get-process "lurk")))))
+ (setq lurk-ping-timer (run-with-timer lurk-ping-period nil #'lurk-ping-function)))
+
+(defun lurk-connect (network)
+ (if (get-process "lurk")
+ (lurk-display-error "Already connected. Disconnect first.")
+ (if (not (assoc network lurk-networks))
+ (lurk-display-error "Network '" network "' is unknown.")
+ (clrhash lurk-contexts)
+ (setq lurk-current-context nil)
+ (lurk-start-process network)
+ (lurk-send-msg (lurk-msg nil nil "USER" lurk-user-name 0 "*" lurk-full-name))
+ (lurk-send-msg (lurk-msg nil nil "NICK" lurk-nick))
+ (setq lurk-ping-timer (run-with-timer lurk-ping-period nil #'lurk-ping-function)))))
+
+
+(defun lurk-send-msg (msg)
+ (let ((proc (get-process "lurk")))
+ (if (and proc (eq (process-status proc) 'open))
+ (process-send-string proc (concat (lurk-msg->string msg) "\r\n"))
+ (lurk-display-error "No server connection established.")
+ (error "No server connection established"))))
+
+
+;;; Server messages
+;;
+
+(defun lurk--as-string (obj)
+ (if obj
+ (with-output-to-string (princ obj))
+ nil))
+
+(defun lurk-msg (tags src cmd &rest params)
+ (list (lurk--as-string tags)
+ (lurk--as-string src)
+ (upcase (lurk--as-string cmd))
+ (mapcar #'lurk--as-string
+ (if (and params (listp (elt params 0)))
+ (elt params 0)
+ params))))
+
+(defun lurk-msg-tags (msg) (elt msg 0))
+(defun lurk-msg-src (msg) (elt msg 1))
+(defun lurk-msg-cmd (msg) (elt msg 2))
+(defun lurk-msg-params (msg) (elt msg 3))
+(defun lurk-msg-trail (msg)
+ (let ((params (lurk-msg-params msg)))
+ (if params
+ (elt params (- (length params) 1)))))
+
+(defvar lurk-msg-regex
+ (rx
+ (opt (: "@" (group (* (not (or "\n" "\r" ";" " ")))))
+ (* whitespace))
+ (opt (: ":" (: (group (* (not (any space "!" "@"))))
+ (* (not (any space)))))
+ (* whitespace))
+ (group (: (* (not whitespace))))
+ (* whitespace)
+ (opt (group (+ not-newline))))
+ "Regex used to parse IRC messages.
+Note that this regex is incomplete. Noteably, we discard the non-nick
+portion of the source component of the message, as LURK doesn't use this.")
+
+(defun lurk-string->msg (string)
+ (if (string-match lurk-msg-regex string)
+ (let* ((tags (match-string 1 string))
+ (src (match-string 2 string))
+ (cmd (upcase (match-string 3 string)))
+ (params-str (match-string 4 string))
+ (params
+ (if params-str
+ (let* ((idx (cl-search ":" params-str))
+ (l (split-string (string-trim (substring params-str 0 idx))))
+ (r (if idx (list (substring params-str (+ 1 idx))) nil)))
+ (append l r))
+ nil)))
+ (apply #'lurk-msg (append (list tags src cmd) params)))
+ (error "Failed to parse string " string)))
+
+(defun lurk--filtered-join (&rest args)
+ (string-join (seq-filter (lambda (el) el) args) " "))
+
+(defun lurk-msg->string (msg)
+ (let ((tags (lurk-msg-tags msg))
+ (src (lurk-msg-src msg))
+ (cmd (lurk-msg-cmd msg))
+ (params (lurk-msg-params msg)))
+ (lurk--filtered-join
+ (if tags (concat "@" tags) nil)
+ (if src (concat ":" src) nil)
+ cmd
+ (if (> (length params) 1)
+ (string-join (seq-take params (- (length params) 1)) " ")
+ nil)
+ (if (> (length params) 0)
+ (concat ":" (elt params (- (length params) 1)))
+ nil))))
+
+
+;;; Contexts and users
+;;
+
+(defvar lurk-context-table
+ '((channel lurk-display-channel-message)
+ (nick lurk-display-private-message)
+ (host lurk-diaplay-server-message)))
+
+(defvar lurk-current-context nil)
+(defvar lurk-contexts (make-hash-table :test #'equal))
+
+(defun lurk-add-context (name)
+ (puthash name nil lurk-contexts))
+
+(defun lurk-del-context (name)
+ (remhash name lurk-contexts))
+
+(defun lurk-get-context-users (name)
+ (gethash name lurk-contexts))
+
+(defun lurk-add-context-users (context users)
+ (puthash context
+ (append users
+ (gethash context lurk-contexts))
+ lurk-contexts))
+
+(defun lurk-del-context-user (context user)
+ (puthash context
+ (remove user (gethash context lurk-contexts))
+ lurk-contexts))
+
+(defun lurk-del-user (user)
+ (dolist (context (lurk-get-context-list))
+ (lurk-del-context-user context user)))
+
+(defun lurk-get-context-type (name)
+ (cond
+ ((string-prefix-p "#" name) 'channel)
+ ((string-match-p (rx (or "." "localhost")) name) 'host)
+ (t 'nick)))
+
+(defun lurk-get-context-list ()
+ (let ((res nil))
+ (maphash (lambda (key val)
+ (cl-pushnew key res))
+ lurk-contexts)
+ res))
+
+(defun lurk-get-next-context (&optional prev)
+ (if lurk-current-context
+ (let* ((context-list (if prev
+ (reverse (lurk-get-context-list))
+ (lurk-get-context-list)))
+ (context-list* (member lurk-current-context context-list)))
+ (if (> (length context-list*) 1)
+ (cadr context-list*)
+ (car context-list)))
+ nil))
+
+(defun lurk-cycle-contexts (&optional rev)
+ (if lurk-current-context
+ (progn
+ (setq lurk-current-context (lurk-get-next-context rev))
+ (lurk-render-prompt))
+ (lurk-display-error "No channels joined.")))
+
+(defun lurk-cycle-contexts-forward ()
+ (interactive)
+ (lurk-cycle-contexts))
+
+(defun lurk-cycle-contexts-reverse ()
+ (interactive)
+ (lurk-cycle-contexts t))
+
+;;; Buffer
+;;
+
+(defun lurk-display-string (&rest strings)
+ (with-current-buffer (get-buffer-create "*lurk*")
+ (save-excursion
+ (goto-char lurk-prompt-marker)
+ (let ((inhibit-read-only t)
+ (old-pos (marker-position lurk-prompt-marker))
+ (adaptive-fill-regexp (rx (= 6 anychar))))
+ (insert-before-markers
+ (propertize (concat (format-time-string "%H:%M") " ")
+ 'face 'lurk-text
+ 'read-only t)
+ (propertize (concat (apply #'concat strings) "\n")
+ 'read-only t))
+ (fill-region old-pos lurk-prompt-marker)))))
+
+(defun lurk-render-prompt ()
+ (with-current-buffer "*lurk*"
+ (let ((update-point (= lurk-input-marker (point)))
+ (update-window-points (mapcar (lambda (w)
+ (list (= (window-point w) lurk-input-marker)
+ w))
+ (get-buffer-window-list nil nil t))))
+ (save-excursion
+ (set-marker-insertion-type lurk-prompt-marker nil)
+ (set-marker-insertion-type lurk-input-marker t)
+ (let ((inhibit-read-only t))
+ (delete-region lurk-prompt-marker lurk-input-marker)
+ (goto-char lurk-prompt-marker)
+ (insert
+ (propertize (if lurk-current-context
+ lurk-current-context
+ "")
+ 'face 'lurk-context
+ 'read-only t)
+ (propertize lurk-prompt-string
+ 'face 'lurk-prompt
+ 'read-only t
+ 'rear-nonsticky t)))
+ (set-marker-insertion-type lurk-input-marker nil))
+ (if update-point
+ (goto-char lurk-input-marker))
+ (dolist (v update-window-points)
+ (if (car v)
+ (set-window-point (cadr v) lurk-input-marker))))))
+
+(defvar lurk-prompt-marker nil
+ "Marker for prompt position in LURK buffer.")
+
+(defvar lurk-input-marker nil
+ "Marker for prompt position in LURK buffer.")
+
+(defun lurk-setup-buffer ()
+ (with-current-buffer (get-buffer-create "*lurk*")
+ (if (markerp lurk-prompt-marker)
+ (set-marker lurk-prompt-marker (point-max))
+ (setq lurk-prompt-marker (point-max-marker)))
+ (if (markerp lurk-input-marker)
+ (set-marker lurk-input-marker (point-max))
+ (setq lurk-input-marker (point-max-marker)))
+ (goto-char (point-max))
+ (lurk-render-prompt)))
+
+
+;;; Output formatting
+;;
+
+(defun lurk-display-message (from to text)
+ (let* ((to-type (lurk-get-context-type to))
+ (display-fun (cadr (assoc to-type lurk-context-table))))
+ (funcall display-fun from to text)))
+
+(defun lurk-display-channel-message (from to text)
+ (lurk-display-string
+ (propertize (concat to
+ " <" from "> "
+ text)
+ 'face 'lurk-text)))
+
+
+(defun lurk-display-action (channel-name nick action)
+ (lurk-display-string (concat channel-name
+ " * "
+ (propertize (concat nick " " action)
+ 'face 'lurk-text))))
+
+(defun lurk-display-private-message (from to text)
+ (lurk-display-string
+ (concat
+ (propertize
+ (concat "[" from " -> " to "] "
+ text)
+ 'face 'lurk-text))))
+
+
+(defun lurk-display-notice (&rest notices)
+ (lurk-display-string lurk-notice-prefix " " (apply #'concat notices)))
+
+(defun lurk-display-error (&rest messages)
+ (lurk-display-string lurk-error-prefix " "
+ (propertize (apply #'concat messages)
+ 'face 'lurk-error)))
+
+;;; Message evaluation
+;;
+
+(defun lurk-eval-msg-string (string)
+ ;; (lurk-display-string string)
+ (let* ((msg (lurk-string->msg string)))
+ (pcase (lurk-msg-cmd msg)
+ ("PING"
+ (lurk-send-msg
+ (lurk-msg nil nil "PONG" (lurk-msg-params msg)))
+ (lurk-display-notice "ping-pong"))
+
+ ("353" ; NAMEREPLY
+ (let* ((params (lurk-msg-params msg))
+ (channel (elt params 2))
+ (names (split-string (elt params 3))))
+ (lurk-add-context-users channel names)))
+
+ ("366" ; ENDOFNAMES
+ (lurk-display-notice
+ (lurk--as-string (length (lurk-get-context-users lurk-current-context)))
+ " users in " lurk-current-context))
+
+ ((rx (= 3 (any digit)))
+ (lurk-display-notice (mapconcat 'identity (cdr (lurk-msg-params msg)) " ")))
+
+ ((and "JOIN"
+ (guard (equal lurk-nick (lurk-msg-src msg))))
+ (let ((channel-name (car (lurk-msg-params msg))))
+ (lurk-add-context channel-name)
+ (setq lurk-current-context channel-name)
+ (lurk-display-notice "Joining channel " channel-name)
+ (lurk-render-prompt)))
+
+ ("JOIN"
+ (let ((channel-name (car (lurk-msg-params msg)))
+ (nick (lurk-msg-src msg)))
+ (lurk-add-context-users channel-name (list nick))
+ (lurk-display-notice nick " joined channel " channel-name)))
+
+ ((and "PART"
+ (guard (equal lurk-nick (lurk-msg-src msg))))
+ (let ((channel-name (car (lurk-msg-params msg))))
+ (lurk-display-notice "Left channel " channel-name)
+ (lurk-del-context channel-name)
+ (if (equal channel-name lurk-current-context)
+ (setq lurk-current-context (lurk-get-next-context)))
+ (lurk-render-prompt)))
+
+ ("PART"
+ (let ((channel-name (car (lurk-msg-params msg)))
+ (nick (lurk-msg-src msg)))
+ (lurk-del-context-user channel-name nick)
+ (lurk-display-notice nick " left channel " channel-name)))
+
+ ("QUIT"
+ (let ((nick (lurk-msg-src msg))
+ (reason (mapconcat 'identity (lurk-msg-params msg) " ")))
+ (lurk-del-user nick)
+ (lurk-display-notice nick " quit: " reason)))
+
+ ((and "NICK"
+ (guard (equal lurk-nick (lurk-msg-src msg))))
+ (setq lurk-nick (car (lurk-msg-params msg)))
+ (lurk-display-notice "Set nick to " lurk-nick))
+
+ ("NICK"
+ (let ((old-nick (lurk-msg-src msg))
+ (new-nick (car (lurk-msg-params msg))))
+ (lurk-display-notice nick " is now known as " new-nick)
+ (lurk-rename-user nick new-nick)))
+
+ ("NOTICE"
+ (let ((nick (lurk-msg-src msg))
+ (channel (car (lurk-msg-params msg)))
+ (text (cadr (lurk-msg-params msg))))
+ (pcase text
+ ((rx (: "\01VERSION "
+ (let version (* (not "\01")))
+ "\01"))
+ (lurk-display-notice "CTCP version reply from " nick ": " version))
+ (_
+ (lurk-display-notice text)))))
+
+ ("PRIVMSG"
+ (let* ((from (lurk-msg-src msg))
+ (params (lurk-msg-params msg))
+ (to (car params))
+ (text (cadr params)))
+ (pcase text
+ ("\01VERSION\01"
+ (let ((version-string (concat lurk-version " - running on GNU Emacs " emacs-version)))
+ (lurk-send-msg (lurk-msg nil nil "NOTICE"
+ (list from (concat "\01VERSION "
+ version-string
+ "\01")))))
+ (lurk-display-notice "CTCP version request received from " from))
+
+ ((rx (let ping (: "\01PING " (* (not "\01")) "\01")))
+ (lurk-send-msg (lurk-msg nil nil "NOTICE" (list from ping)))
+ (lurk-display-notice "CTCP ping received from " from))
+
+ ("\01USERINFO\01"
+ (lurk-display-notice "CTCP userinfo request from " from " (no response sent)"))
+
+ (_
+ (lurk-display-message from to text)))))
+ (_
+ (lurk-display-string (lurk-msg->string msg))))))
+
+
+;;; Command entering
+;;
+
+(defun lurk-enter-string (string)
+ (if (string-prefix-p "/" string)
+ (pcase (substring string 1)
+ ((rx (: "CONNECT " (let network (* not-newline))))
+ (lurk-display-notice "Attempting to connect to " network "...")
+ (lurk-connect network))
+
+ ((rx (: "TOPIC " (let new-topic (* not-newline))))
+ (lurk-send-msg (lurk-msg nil nil "TOPIC" lurk-current-context new-topic)))
+
+ ((rx (: "ME " (let action (* not-newline))))
+ (lurk-send-msg (lurk-msg nil nil "PRIVMSG"
+ (list lurk-current-context
+ (concat "\01ACTION " action "\01"))))
+ (lurk-display-action lurk-nick action))
+
+ ((rx (: "VERSION" " " (let nick (* (not whitespace)))))
+ (lurk-send-msg (lurk-msg nil nil "PRIVMSG"
+ (list nick "\01VERSION\01")))
+ (lurk-display-notice "CTCP version request sent to " nick))
+
+ ((rx "PART" (opt (: " " (let channel (* not-newline)))))
+ (if (or lurk-current-context channel)
+ (lurk-send-msg (lurk-msg nil nil "PART" (if channel
+ channel
+ lurk-current-context)))
+ (lurk-display-error "No current channel to leave.")))
+
+ ((rx "MSG "
+ (let to (* (not whitespace)))
+ " "
+ (let text (* not-newline)))
+ (lurk-send-msg (lurk-msg nil nil "PRIVMSG" to text))
+ (lurk-display-message lurk-nick to text))
+
+ ((rx (: (let cmd-str (+ (not whitespace)))
+ (opt (: " " (let params-str (* not-newline))))))
+ (lurk-send-msg (lurk-msg nil nil (upcase cmd-str)
+ (if params-str
+ (split-string params-str)
+ nil)))))
+
+ (unless (string-empty-p string)
+ (if lurk-current-context
+ (progn
+ (lurk-send-msg (lurk-msg nil nil "PRIVMSG"
+ lurk-current-context
+ string))
+ (lurk-display-message lurk-nick lurk-current-context string))
+ (lurk-display-error "No current context.")))))
+
+(defun lurk-enter ()
+ "Enter current contents of line after prompt."
+ (interactive)
+ (with-current-buffer "*lurk*"
+ (lurk-enter-string
+ (buffer-substring lurk-input-marker (point-max)))
+ (let ((inhibit-read-only t))
+ (delete-region lurk-input-marker (point-max)))))
+
+
+;;; Mode
+;;
+
+(defvar lurk-mode-map
+ (let ((map (make-sparse-keymap)))
+ (define-key map (kbd "RET") 'lurk-enter)
+ (define-key map (kbd "<C-tab>") 'lurk-cycle-contexts-forward)
+ (define-key map (kbd "<C-S-tab>") 'lurk-cycle-contexts-reverse)
+ map))
+
+(define-derived-mode lurk-mode text-mode "lurk"
+ "Major mode for LURK.")
+
+(when (fboundp 'evil-set-initial-state)
+ (evil-set-initial-state 'lurk-mode 'insert))
+
+;;; Main start procedure
+;;
+
+(defun lurk ()
+ "Switch to *lurk* buffer."
+ (interactive)
+ (if (get-buffer "*lurk*")
+ (switch-to-buffer "*lurk*")
+ (switch-to-buffer "*lurk*"))
+ (lurk-mode)
+ (lurk-setup-buffer)
+ "Started LURK.")
+
+
+
+;;; lurk.el ends here