X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?p=lurk.git;a=blobdiff_plain;f=lurk.el;h=edfb66fe7d6b79b90021d2d35b7a8c79ea85c7df;hp=531e426191d805afe9316bcf7cc2aaf193a5095c;hb=HEAD;hpb=d874c02a112bb7e965a86955ecc88d379b0358c0

diff --git a/lurk.el b/lurk.el
index 531e426..52ee3b6 100644
--- a/lurk.el
+++ b/lurk.el
@@ -1,4 +1,4 @@
-;;; lurk.el --- Little Uni-buffer iRc Klient -*- lexical-binding:t -*-
+;;; lurk.el --- Little Unibuffer iRc Klient -*- lexical-binding:t -*-
 
 ;; Copyright (C) 2021 Tim Vaughan
 
@@ -35,7 +35,7 @@
 ;;
 
 (defgroup lurk nil
-  "Little Uni-buffer iRc Klient."
+  "Little Unibuffer iRc Klient."
   :group 'network)
 
 (defcustom lurk-nick "plugd"
@@ -45,11 +45,7 @@
   "Default quit message when none supplied.")
 
 (defcustom lurk-networks
-  '(("libera" "irc.libera.chat" 6697)
-    ("freenode" "chat.freenode.net" 6697)
-    ("tilde" "tilde.chat" 6697)
-    ("mbr" "mbrserver.com" 6667 :notls)
-    ("local" "localhost" 6697))
+  '(("libera" "irc.libera.chat" 6697))
   "IRC networks.")
 
 (defcustom lurk-allow-ipv6 nil
@@ -69,27 +65,27 @@
   "Face used for Lurk text.")
 
 (defface lurk-prompt
-  '((t :inherit org-priority))
+  '((t :inherit font-lock-keyword-face))
   "Face used for the prompt.")
 
 (defface lurk-context
-  '((t :inherit org-tag))
+  '((t :inherit lurk-context))
   "Face used for the context name in the prompt.")
 
 (defface lurk-faded
-  '((t :inherit org-agenda-dimmed-todo-face))
+  '((t :inherit shadow))
   "Face used for faded Lurk text.")
 
 (defface lurk-timestamp
-  '((t :inherit org-agenda-dimmed-todo-face))
+  '((t :inherit shadow))
   "Face used for timestamps.")
 
 (defface lurk-error
-  '((t :inherit font-lock-regexp-grouping-construct))
+  '((t :inherit error))
   "Face used for Lurk error text.")
 
 (defface lurk-notice
-  '((t :inherit org-upcoming-deadline))
+  '((t :inherit warning))
   "Face used for Lurk notice text.")
 
 ;;; Global variables
@@ -107,6 +103,19 @@
 (defvar lurk-debug nil
   "If non-nil, enable debug mode.")
 
+
+;;; Utility procedures
+;;
+
+(defun lurk--filtered-join (&rest args)
+  (string-join (seq-filter (lambda (el) el) args) " "))
+
+(defun lurk--as-string (obj)
+  (if obj
+      (with-output-to-string (princ obj))
+    nil))
+
+
 ;;; Network process
 ;;
 
@@ -182,11 +191,6 @@
 ;;; 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)
@@ -235,9 +239,6 @@ portion of the source component of the message, as LURK doesn't use this.")
         (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))
@@ -270,10 +271,13 @@ portion of the source component of the message, as LURK doesn't use this.")
 (defun lurk-get-context-users (name)
   (gethash name lurk-contexts))
 
+(defun lurk-context-known-p (name)
+  (not (eq (gethash name lurk-contexts 0) 0)))
+
 (defun lurk-add-context-users (context users)
   (puthash context
-           (append users
-                   (gethash context lurk-contexts))
+           (cl-union users
+                     (gethash context lurk-contexts))
            lurk-contexts))
 
 (defun lurk-del-context-user (context user)
@@ -317,14 +321,13 @@ portion of the source component of the message, as LURK doesn't use this.")
 (defun lurk-set-current-context (context)
   (setq lurk-current-context context)
   (lurk-highlight-context context)
+  (lurk-render-prompt)
   (if lurk-zoomed
       (lurk-zoom-in lurk-current-context)))
 
 (defun lurk-cycle-contexts (&optional rev)
   (if lurk-current-context
-      (progn
-        (lurk-set-current-context (lurk-get-next-context rev))
-        (lurk-render-prompt))
+      (lurk-set-current-context (lurk-get-next-context rev))
     (lurk-display-error "No channels joined.")))
 
 
@@ -350,8 +353,10 @@ portion of the source component of the message, as LURK doesn't use this.")
                          "")
                        'face 'lurk-context
                        'read-only t)
-           (propertize (concat lurk-prompt-string " ")
+           (propertize lurk-prompt-string
                        'face 'lurk-prompt
+                       'read-only t)
+           (propertize " " ; Need this to be separate to mark it as rear-nonsticky
                        'read-only t
                        'rear-nonsticky t)))
         (set-marker-insertion-type lurk-input-marker nil))
@@ -368,22 +373,25 @@ portion of the source component of the message, as LURK doesn't use this.")
   "Marker for prompt position in LURK buffer.")
 
 (defun lurk-setup-header ()
-  (setq-local header-line-format
-              '(:eval
-                (let ((proc (get-process "lurk")))
-                  (if proc
-                      (concat
-                       "Host: " (car (process-contact proc))
-                       ", Context: "
-                       (if lurk-current-context
-                           (concat
-                            lurk-current-context
-                            " ("
-                            (number-to-string
-                             (length (lurk-get-context-users lurk-current-context)))
-                            " users)")
-                         "Server"))
-                    "No connection")))))
+  (with-current-buffer "*lurk*"
+    (setq-local header-line-format
+                '((:eval
+                   (let ((proc (get-process "lurk")))
+                     (if proc
+                         (concat
+                          "Host: " (car (process-contact proc))
+                          ", Context: "
+                          (if lurk-current-context
+                              (concat
+                               lurk-current-context
+                               " ("
+                               (number-to-string
+                                (length (lurk-get-context-users lurk-current-context)))
+                               " users)")
+                            "Server"))
+                       "No connection")))
+                  (:eval
+                   (if lurk-zoomed " [ZOOMED]" ""))))))
 
 (defun lurk-setup-buffer ()
   (with-current-buffer (get-buffer-create "*lurk*")
@@ -400,15 +408,20 @@ portion of the source component of the message, as LURK doesn't use this.")
     (if lurk-display-header
         (lurk-setup-header))))
 
+(defun lurk-clear-buffer ()
+  "Completely erase all non-prompt and non-input text from lurk buffer."
+  (with-current-buffer "*lurk*"
+    (let ((inhibit-read-only t))
+      (delete-region (point-min) lurk-prompt-marker))))
 
 ;;; Output formatting and highlighting
 ;;
 
-;; Partially-implemented idea: the face text property can be
-;; a list of faces, applied in order.  By assigning each context
-;; a unique list and keeping track of these in a hash table, we can
-;; easily switch the face corresponding to a particular context
-;; by modifying the elements of this list.
+;; Idea: the face text property can be a list of faces, applied in
+;; order.  By assigning each context a unique list and keeping track
+;; of these in a hash table, we can easily switch the face
+;; corresponding to a particular context by modifying the elements of
+;; this list.
 ;;
 ;; More subtly, we make only the cdrs of this list shared among
 ;; all text of a given context, allowing the cars to be different
@@ -437,8 +450,35 @@ portion of the source component of the message, as LURK doesn't use this.")
       (fill-region (point-min) (point-max) nil t)
       (buffer-string))))
 
+(defun lurk--start-of-final-line ()
+  (with-current-buffer "*lurk*"
+    (save-excursion
+      (goto-char (point-max))
+      (line-beginning-position))))
+
+(defun lurk-scroll-windows-to-last-line ()
+  (with-current-buffer "*lurk*"
+    (dolist (window (get-buffer-window-list))
+      (if (>= (window-point window) (lurk--start-of-final-line))
+          (with-selected-window window
+            (recenter -1))))))
+
+(defun lurk-make-context-button (context &optional label)
+  (with-temp-buffer
+    (insert-text-button (or label context)
+                        'action #'lurk--context-button-action
+                        'follow-link t
+                        'help-echo "Switch context.")
+    (buffer-string)))
+
+(defun lurk--context-button-action (button)
+  (let ((context (button-get button 'context)))
+    (if (eq lurk-current-context context)
+        (lurk-toggle-zoom)
+      (lurk-set-current-context context))))
+
 (defun lurk-display-string (context prefix &rest strings)
-  (with-current-buffer (get-buffer-create "*lurk*")
+  (with-current-buffer "*lurk*"
     (save-excursion
       (goto-char lurk-prompt-marker)
       (let* ((inhibit-read-only t)
@@ -460,11 +500,13 @@ portion of the source component of the message, as LURK doesn't use this.")
                       'read-only t
                       'context context
                       'invisible context-atom)
-          (propertize (concat (lurk-buttonify-urls (apply #'concat strings)) "\n")
-                      'face (lurk-get-context-facelist context)
-                      'read-only t
-                      'context context
-                      'invisible context-atom)))))))
+          (lurk-add-formatting
+           (propertize (concat (apply #'lurk-buttonify-urls strings) "\n")
+                       'face (lurk-get-context-facelist context)
+                       'read-only t
+                       'context context
+                       'invisible context-atom)))))))
+  (lurk-scroll-windows-to-last-line))
 
 (defun lurk-display-message (from to text)
   (let ((context (if (eq 'channel (lurk-get-context-type to))
@@ -474,8 +516,10 @@ portion of the source component of the message, as LURK doesn't use this.")
      context
      (propertize
       (pcase (lurk-get-context-type to)
-        ('channel (concat to " <" from ">"))
-        ('nick (concat "[" from " -> " to "]"))
+        ('channel (concat
+                   (lurk-make-context-button to)
+                   " <" from ">"))
+        ('nick (lurk-make-context-button context (concat "[" from " -> " to "]")))
         (_
          (error "Unsupported context type")))
       'face (lurk-get-context-facelist context))
@@ -487,7 +531,9 @@ portion of the source component of the message, as LURK doesn't use this.")
                    (if (equal to lurk-nick) from to))))
     (lurk-display-string
      context
-     (concat context " * " from)
+     (propertize
+      (concat (lurk-make-context-button context) " * " from)
+      'face (lurk-get-context-facelist context))
      action-text)))
 
 (defun lurk-display-notice (context &rest notices)
@@ -521,7 +567,8 @@ portion of the source component of the message, as LURK doesn't use this.")
                (remove-from-invisibility-spec this-context-atom)
              (add-to-invisibility-spec this-context-atom)))))
      lurk-context-facelists)
-    (force-window-update "*lurk*")))
+    (force-window-update "*lurk*"))
+  (lurk-scroll-windows-to-last-line))
 
 (defun lurk-zoom-out ()
   (with-current-buffer "*lurk*"
@@ -530,7 +577,18 @@ portion of the source component of the message, as LURK doesn't use this.")
        (let ((this-context-atom (if this-context (intern this-context) nil)))
          (remove-from-invisibility-spec this-context-atom)))
      lurk-context-facelists)
-    (force-window-update "*lurk*")))
+    (force-window-update "*lurk*"))
+  (lurk-scroll-windows-to-last-line))
+
+(defun lurk-clear-context (context)
+  (with-current-buffer "*lurk*"
+    (save-excursion
+      (goto-char (point-min))
+      (let ((inhibit-read-only t)
+            (match nil))
+        (while (setq match (text-property-search-forward 'context context t))
+          (delete-region (prop-match-beginning match)
+                         (prop-match-end match)))))))
 
 (defconst lurk-url-regex
   (rx (:
@@ -541,17 +599,17 @@ portion of the source component of the message, as LURK doesn't use this.")
        (opt (group (: ":" (+ digit))))
        (opt (group (: "/"
                       (opt
-                       (* (any alnum "-/.,#:%=&_"))
-                       (any alnum "-/#:%=&_")))))))
+                       (* (any alnum "-/.,#:%=&_?~@+"))
+                       (any alnum "-/#:%=&_~@+")))))))
   "Imperfect regex used to find URLs in plain text.")
 
 (defun lurk-click-url (button)
   (browse-url (button-get button 'url)))
 
-(defun lurk-buttonify-urls (string)
+(defun lurk-buttonify-urls (&rest strings)
   "Turn substrings which look like urls in STRING into clickable buttons."
   (with-temp-buffer
-    (insert string)
+    (apply #'insert strings)
     (goto-char (point-min))
     (while (re-search-forward lurk-url-regex nil t)
       (let ((url (match-string 0)))
@@ -564,6 +622,42 @@ portion of the source component of the message, as LURK doesn't use this.")
                           'help-echo "Open URL in browser.")))
     (buffer-string)))
 
+(defun lurk-add-formatting (string)
+  (with-temp-buffer
+    (insert string)
+    (goto-char (point-min))
+    (let ((bold nil)
+          (italics nil)
+          (underline nil)
+          (strikethrough nil)
+          (prev-point (point)))
+      (while (re-search-forward (rx (or (any "\x02\x1D\x1F\x1E\x0F")
+                                        (: "\x03" (+ digit) (opt "," (* digit)))))
+                                nil t)
+        (let ((beg (+ (match-beginning 0) 1)))
+          (if bold
+              (add-face-text-property prev-point beg '(:weight bold)))
+          (if italics
+              (add-face-text-property prev-point beg '(:slant italic)))
+          (if underline
+              (add-face-text-property prev-point beg '(:underline t)))
+          (if strikethrough
+              (add-face-text-property prev-point beg '(:strike-through t)))
+          (pcase (match-string 0)
+            ("\x02" (setq bold (not bold)))
+            ("\x1D" (setq italics (not italics)))
+            ("\x1F" (setq underline (not underline)))
+            ("\x1E" (setq strikethrough (not strikethrough)))
+            ("\x0F" ; Reset
+             (setq bold nil)
+             (setq italics nil)
+             (setq underline nil)
+             (setq strikethrough nil))
+            (_))
+          (delete-region (match-beginning 0) (match-end 0))
+          (setq prev-point (point)))))
+    (buffer-string)))
+
 
 ;;; Message evaluation
 ;;
@@ -572,6 +666,7 @@ portion of the source component of the message, as LURK doesn't use this.")
   (if lurk-debug
       (lurk-display-string nil nil string))
   (let* ((msg (lurk-string->msg string)))
+    (lurk-process-autoreplies msg)
     (pcase (lurk-msg-cmd msg)
       ("PING"
        (lurk-send-msg
@@ -590,15 +685,19 @@ portion of the source component of the message, as LURK doesn't use this.")
        (let* ((params (lurk-msg-params msg))
               (channel (elt params 2))
               (names (split-string (elt params 3))))
-         (lurk-add-context-users channel names)))
+         (if (lurk-context-known-p channel)
+             (lurk-add-context-users channel names)
+           (lurk-display-notice nil "Users in " channel ": " (string-join names " ")))))
 
       ("366" ; ENDOFNAMES
        (let* ((params (lurk-msg-params msg))
               (channel (elt params 1)))
-         (lurk-display-notice
-          channel
-          (lurk--as-string (length (lurk-get-context-users channel)))
-          " users in " channel)))
+         (if (lurk-context-known-p channel)
+             (lurk-display-notice
+              channel
+              (lurk--as-string (length (lurk-get-context-users channel)))
+              " users in " channel)
+           (lurk-display-notice nil "End of " channel " names list."))))
 
       ("331"
        (let* ((params (lurk-msg-params msg))
@@ -724,82 +823,244 @@ portion of the source component of the message, as LURK doesn't use this.")
        (lurk-display-notice nil (lurk-msg->string msg))))))
 
 
+;;; User-defined responses
+
+
+(defvar lurk-autoreply-table nil
+  "Table of autoreply messages.
+
+Each autoreply is a list of two elements: (matcher reply)
+
+Here matcher is a list:
+
+(network src cmd params ...)
+
+and reply is another list:
+
+ (cmd params ...)
+
+Each entry in the matcher list is a regular expression tested against the
+corresponding values in the incomming message.  Entries can be nil,
+in which case they match anything.")
+
+(defun lurk--lists-equal (l1 l2)
+    (if (and l1 l2)
+        (if (or (not (and (car l1) (car l2)))
+                (string-match (car l1) (car l2)))
+            (lurk--lists-equal (cdr l1) (cdr l2))
+          nil)
+      t))
+
+(defun lurk-process-autoreply (msg autoreply)
+  (let ((matcher (car autoreply))
+        (reply (cadr autoreply)))
+    (let ((network (car matcher)))
+      (when (and (or (not network)
+                     (and (get-process "lurk")
+                          (equal (car (process-contact (get-process "lurk")))
+                                 (cadr (assoc network lurk-networks)))))
+                 (lurk--lists-equal (cdr matcher)
+                                    (append (list (lurk-msg-src msg)
+                                                  (lurk-msg-cmd msg))
+                                            (lurk-msg-params msg))))
+        (lurk-send-msg
+         (lurk-msg nil nil (car reply) (cdr reply)))))))
+
+(defun lurk-process-autoreplies (msg)
+  (mapc
+   (lambda (autoreply)
+     (lurk-process-autoreply msg autoreply))
+   lurk-autoreply-table))
+
+
+;;; Commands
+;;
+
+(defvar lurk-command-table
+  '(("DEBUG" "Toggle debug mode on/off." lurk-command-debug lurk-boolean-completions)
+    ("HEADER" "Toggle display of header." lurk-command-header lurk-boolean-completions)
+    ("CONNECT" "Connect to an IRC network." lurk-command-connect lurk-network-completions)
+    ("NETWORKS" "List known IRC networks." lurk-command-networks)
+    ("JOIN" "Join one or more channels." lurk-command-join)
+    ("TOPIC" "Set topic for current channel." lurk-command-topic)
+    ("ME" "Display action." lurk-command-me)
+    ("VERSION" "Request version of another user's client via CTCP." lurk-command-version lurk-nick-completions)
+    ("PART" "Leave channel." lurk-command-part lurk-context-completions)
+    ("QUIT" "Disconnect from current network." lurk-command-quit)
+    ("NICK" "Change nick." lurk-command-nick)
+    ("LIST" "Display details of one or more channels." lurk-command-list)
+    ("WHOIS" "Ask server for details of nick." nil lurk-nick-completions)
+    ("USERS" "List nicks of users in current context." lurk-command-users)
+    ("MSG" "Send private message to user." lurk-command-msg lurk-nick-completions)
+    ("CLEAR" "Clear buffer text." lurk-command-clear lurk-context-completions)
+    ("HELP" "Display help on client commands." lurk-command-help lurk-help-completions))
+  "Table of commands explicitly supported by Lurk.")
+
+(defun lurk-boolean-completions ()
+  '("on" "off"))
+
+(defun lurk-network-completions ()
+  (mapcar (lambda (row) (car row)) lurk-networks))
+
+(defun lurk-nick-completions ()
+  (lurk-get-context-users lurk-current-context))
+
+(defun lurk-context-completions ()
+  (lurk-get-context-list))
+
+(defun lurk-help-completions ()
+  (mapcar (lambda (row) (car row)) lurk-command-table))
+
+(defun lurk-command-help (params)
+  (if params
+      (let* ((cmd-str (upcase (car params)))
+             (row (assoc cmd-str lurk-command-table #'equal)))
+        (if row
+            (progn
+              (lurk-display-notice nil "Help for \x02" cmd-str "\x02:")
+              (lurk-display-notice nil "  " (elt row 1)))
+          (lurk-display-notice nil "No such (client-interpreted) command.")))
+    (lurk-display-notice nil "Client-interpreted commands:")
+    (dolist (row lurk-command-table)
+      (lurk-display-notice nil "  \x02" (elt row 0) "\x02: " (elt row 1)))
+    (lurk-display-notice nil "Use /HELP COMMAND to display information about a specific command.")))
+
+(defun lurk-command-debug (params)
+  (setq lurk-debug 
+        (if params
+            (if (equal (upcase (car params)) "ON")
+                t
+              nil)
+          (not lurk-debug)))
+  (lurk-display-notice nil "Debug mode now " (if lurk-debug "on" "off") "."))
+
+(defun lurk-command-header (params)
+  (if
+      (if params
+          (equal (upcase (car params)) "ON")
+        (not header-line-format))
+      (progn
+        (lurk-setup-header)
+        (lurk-display-notice nil "Header enabled."))
+    (setq-local header-line-format nil)
+    (lurk-display-notice nil "Header disabled.")))
+
+(defun lurk-command-connect (params)
+  (if params
+      (let ((network (car params)))
+        (lurk-display-notice nil "Attempting to connect to " network "...")
+        (lurk-connect network))
+    (lurk-display-notice nil "Usage: /connect <network>")))
+
+(defun lurk-command-networks (params)
+  (lurk-display-notice nil "Currently-known networks:")
+  (dolist (row lurk-networks)
+    (seq-let (network server port &rest others) row
+      (lurk-display-notice nil "\t" network
+                           " [" server
+                           " " (number-to-string port) "]")))
+  (lurk-display-notice nil "(Modify the `lurk-networks' variable to add more.)"))
+
+(defun lurk-command-join (params)
+  (if params
+      (dolist (channel params)
+        (lurk-send-msg (lurk-msg nil nil "JOIN" channel)))
+    (lurk-display-notice nil "Usage: /join channel [channel2 ...]")))
+
+(defun lurk-command-part (params)
+  (let ((channel (if params (car params) lurk-current-context)))
+    (if channel
+        (lurk-send-msg (lurk-msg nil nil "PART" channel))
+      (lurk-display-error "No current channel to leave."))))
+
+(defun lurk-command-version (params)
+  (if params
+      (let ((nick (car params)))
+        (lurk-send-msg (lurk-msg nil nil "PRIVMSG"
+                                 (list nick "\01VERSION\01")))
+        (lurk-display-notice nil "CTCP version request sent to " nick))
+    (lurk-display-notice nil "Usage: /version <nick>")))
+
+(defun lurk-command-quit (params)
+  (let ((quit-msg (if params (string-join params " ") lurk-default-quit-msg)))
+    (lurk-send-msg (lurk-msg nil nil "QUIT" quit-msg))))
+
+(defun lurk-command-nick (params)
+  (let ((new-nick (if params (string-join params " ") nil)))
+    (if new-nick
+        (if (lurk-connected-p)
+            (lurk-send-msg (lurk-msg nil nil "NICK" new-nick))
+          (setq lurk-nick new-nick)
+          (lurk-display-notice nil "Set default nick to '" lurk-nick "'."))
+      (lurk-display-notice nil "Current nick: " lurk-nick))))
+
+(defun lurk-command-me (params)
+  (if lurk-current-context
+      (if params
+          (let* ((action (string-join params " "))
+                 (ctcp-text (concat "\01ACTION " action "\01")))
+            (lurk-send-msg (lurk-msg nil nil "PRIVMSG"
+                                     (list lurk-current-context ctcp-text)))
+            (lurk-display-action lurk-nick lurk-current-context action))
+        (lurk-display-notice nil "Usage: /me <action>"))
+    (lurk-display-notice nil "No current channel.")))
+
+(defun lurk-command-list (params)
+  (if (not params)
+      (lurk-display-notice nil "This command can generate lots of output. Use `/LIST -yes' if you really want this, or `/LIST <channel_regexp>' to reduce the output.")
+    (if (equal (upcase (car params)) "-YES")
+        (lurk-send-msg (lurk-msg nil nil "LIST"))
+      (lurk-send-msg (lurk-msg nil nil "LIST" (car params))))))
+
+(defun lurk-command-topic (params)
+  (if lurk-current-context
+      (if params
+          (lurk-send-msg (lurk-msg nil nil "TOPIC" lurk-current-context (string-join params " ")))
+        (lurk-display-notice nil "Usage: /topic <new topic>"))
+    (lurk-display-notice nil "No current channel.")))
+
+(defun lurk-command-msg (params)
+  (if (and params (>= (length params) 2))
+      (let ((to (car params))
+            (text (string-join (cdr params) " ")))
+        (lurk-send-msg (lurk-msg nil nil "PRIVMSG" to text))
+        (lurk-display-message lurk-nick to text))
+    (lurk-display-notice nil "Usage: /msg <nick> <message>")))
+
+(defun lurk-command-clear (params)
+  (if (not params)
+      (lurk-clear-buffer)
+    (dolist (context params)
+      (lurk-clear-context context))))
+
+(defun lurk-command-users (params)
+  (if lurk-current-context
+      (progn
+        (lurk-display-notice lurk-current-context "Users in " lurk-current-context ":")
+        (lurk-display-notice
+         lurk-current-context
+         (string-join (lurk-get-context-users lurk-current-context) " ")))
+    (lurk-display-notice nil "No current channel.")))
+
 ;;; Command entering
 ;;
 
 (defun lurk-enter-string (string)
   (if (string-prefix-p "/" string)
-      (pcase (substring string 1)
-        ((rx "DEBUG")
-         (setq lurk-debug (not lurk-debug))
-         (lurk-display-notice nil "Debug mode now " (if lurk-debug "on" "off") "."))
-
-        ((rx "HEADER")
-         (if header-line-format
-           (progn
-             (setq-local header-line-format nil)
-             (lurk-display-notice nil "Header disabled."))
-           (lurk-setup-header)
-           (lurk-display-notice nil "Header enabled.")))
-
-        ((rx (: "CONNECT " (let network (* not-newline))))
-         (lurk-display-notice nil "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))))
-         (let ((ctcp-text (concat "\01ACTION " action "\01")))
-           (lurk-send-msg (lurk-msg nil nil "PRIVMSG"
-                                    (list lurk-current-context ctcp-text)))
-           (lurk-display-action lurk-nick lurk-current-context action)))
-
-        ((rx (: "VERSION" " " (let nick (+ (not whitespace)))))
-         (lurk-send-msg (lurk-msg nil nil "PRIVMSG"
-                                  (list nick "\01VERSION\01")))
-         (lurk-display-notice nil "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 "QUIT" (opt (: " " (let quit-msg (* not-newline)))))
-         (lurk-send-msg (lurk-msg nil nil "QUIT"
-                                  (or quit-msg lurk-default-quit-msg))))
-
-        ((rx (: "NICK" (* whitespace) string-end))
-         (lurk-display-notice nil "Current nick: " lurk-nick))
-
-        ((rx (: "NICK" (+ whitespace) (let nick (+ (not whitespace)))))
-         (if (lurk-connected-p)
-             (lurk-send-msg (lurk-msg nil nil "NICK" nick))
-           (setq lurk-nick nick)
-           (lurk-display-notice nil "Set default nick to '" nick "'")))
-
-        ((rx "LIST")
-         (lurk-display-notice nil "This command can generate lots of output. Use `LIST -yes' if you're sure."))
-
-        ((rx (: "LIST" (+ whitespace) "-YES"))
-         (lurk-send-msg (lurk-msg nil nil "LIST")))
-
-        ((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)))))
-
+      (pcase string
+        ((rx (: "/" (let cmd-str (+ (not whitespace)))
+                (opt (+ whitespace)
+                     (let params-str (+ anychar))
+                     string-end)))
+         (let ((command-row (assoc (upcase  cmd-str) lurk-command-table #'equal))
+               (params (if params-str
+                           (split-string params-str nil t)
+                         nil)))
+           (if (and command-row (elt command-row 2))
+               (funcall (elt command-row 2) params)
+             (lurk-send-msg (lurk-msg nil nil (upcase cmd-str) params)))))
+        (_
+         (lurk-display-error "Badly formed command.")))
     (unless (string-empty-p string)
       (if lurk-current-context
           (progn
@@ -809,20 +1070,12 @@ portion of the source component of the message, as LURK doesn't use this.")
             (lurk-display-message lurk-nick lurk-current-context string))
         (lurk-display-error "No current context.")))))
 
-(defvar lurk-history nil
-  "Commands and messages sent in current session.")
 
+;;; Command history
+;;
 
-(defun lurk-enter ()
-  "Enter current contents of line after prompt."
-  (interactive)
-  (with-current-buffer "*lurk*"
-    (let ((line (buffer-substring lurk-input-marker (point-max))))
-      (push line lurk-history)
-      (setq lurk-history-index nil)
-      (let ((inhibit-read-only t))
-        (delete-region lurk-input-marker (point-max)))
-      (lurk-enter-string line))))
+(defvar lurk-history nil
+  "Commands and messages sent in current session.")
 
 (defvar lurk-history-index nil)
 
@@ -838,13 +1091,6 @@ portion of the source component of the message, as LURK doesn't use this.")
       (delete-region lurk-input-marker (point-max))
       (insert (elt lurk-history lurk-history-index)))))
 
-(defun lurk-history-next ()
-  (interactive)
-  (lurk-history-cycle -1))
-
-(defun lurk-history-prev ()
-  (interactive)
-  (lurk-history-cycle +1))
 
 ;;; Interactive functions
 ;;
@@ -867,16 +1113,54 @@ portion of the source component of the message, as LURK doesn't use this.")
     (lurk-zoom-in lurk-current-context))
   (setq lurk-zoomed (not lurk-zoomed)))
 
-(defun lurk-complete-nick ()
+(defun lurk-history-next ()
+  (interactive)
+  (lurk-history-cycle -1))
+
+(defun lurk-history-prev ()
+  (interactive)
+  (lurk-history-cycle +1))
+
+(defun lurk-complete-input ()
   (interactive)
-  (when (and (>= (point) lurk-input-marker) lurk-current-context)
-    (let* ((end (max lurk-input-marker (point)))
-           (space-idx (save-excursion
-                        (re-search-backward " " lurk-input-marker t)))
-           (start (if space-idx (+ 1 space-idx) lurk-input-marker))
-           (completion-ignore-case t))
-      (unless (string-prefix-p "/" (buffer-substring start end))
-        (completion-in-region start end (lurk-get-context-users lurk-current-context))))))
+  (let ((completion-ignore-case t))
+    (when (>= (point) lurk-input-marker)
+      (pcase (buffer-substring lurk-input-marker (point))
+        ((rx (: "/" (let cmd-str (+ (not whitespace))) (+ " ") (* (not whitespace)) string-end))
+         (let ((space-idx (save-excursion
+                            (re-search-backward " " lurk-input-marker t)))
+               (table-row (assoc (upcase cmd-str) lurk-command-table #'equal)))
+           (if (and table-row (elt table-row 3))
+               (let* ((completions-nospace (funcall (elt table-row 3)))
+                      (completions (mapcar (lambda (el) (concat el " ")) completions-nospace)))
+                 (completion-in-region (+ 1 space-idx) (point) completions)))))
+        ((rx (: "/" (* (not whitespace)) string-end))
+         (message (buffer-substring lurk-input-marker (point)))
+         (completion-in-region lurk-input-marker (point)
+                               (mapcar (lambda (row) (concat "/" (car row) " "))
+                                       lurk-command-table)))
+        (_
+         (let* ((end (max lurk-input-marker (point)))
+                (space-idx (save-excursion
+                             (re-search-backward " " lurk-input-marker t)))
+                (start (if space-idx (+ 1 space-idx) lurk-input-marker)))
+           (unless (string-prefix-p "/" (buffer-substring start end))
+             (let* ((users (lurk-get-context-users lurk-current-context))
+                    (users-no@ (mapcar
+                                (lambda (u) (car (split-string u "@" t)))
+                                users)))
+               (completion-in-region start end users-no@)))))))))
+
+(defun lurk-enter ()
+  "Enter current contents of line after prompt."
+  (interactive)
+  (with-current-buffer "*lurk*"
+    (let ((line (buffer-substring lurk-input-marker (point-max))))
+      (push line lurk-history)
+      (setq lurk-history-index nil)
+      (let ((inhibit-read-only t))
+        (delete-region lurk-input-marker (point-max)))
+      (lurk-enter-string line))))
 
 
 ;;; Mode
@@ -885,37 +1169,38 @@ portion of the source component of the message, as LURK doesn't use this.")
 (defvar lurk-mode-map
   (let ((map (make-sparse-keymap)))
     (define-key map (kbd "RET") 'lurk-enter)
-    (define-key map (kbd "<tab>") 'lurk-complete-nick)
+    (define-key map (kbd "TAB") 'lurk-complete-input)
     (define-key map (kbd "C-c C-z") 'lurk-toggle-zoom)
     (define-key map (kbd "<C-tab>") 'lurk-cycle-contexts-forward)
     (define-key map (kbd "<C-S-tab>") 'lurk-cycle-contexts-reverse)
     (define-key map (kbd "<C-up>") 'lurk-history-prev)
     (define-key map (kbd "<C-down>") 'lurk-history-next)
-    ;; (when (fboundp 'evil-define-key*)
-    ;;   (evil-define-key* 'insert map
-    ;;                     (kbd "<C-Up>") 'lurk-history-prev
-    ;;                     (kbd "<C-Down>") 'lurk-history-next))
+    (when (fboundp 'evil-define-key*)
+      (evil-define-key* 'motion map
+        (kbd "TAB") 'lurk-complete-input))
     map))
 
-(defvar lurk-mode-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."
+(defun lurk (&optional network)
+  "Start lurk or just switch to the lurk buffer if one already exists.
+Also connect to NETWORK if non-nil."
   (interactive)
   (if (get-buffer "*lurk*")
       (switch-to-buffer "*lurk*")
     (switch-to-buffer "*lurk*")
     (lurk-mode)
-    (lurk-setup-buffer))
+    (lurk-setup-buffer)
+    (if network
+        (lurk-command-connect (list network))))
   "Started LURK.")