X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?p=lurk.git;a=blobdiff_plain;f=lurk.el;h=edfb66fe7d6b79b90021d2d35b7a8c79ea85c7df;hp=e519f46c6893c9e5277ab0a5f92f1eecd4e63311;hb=HEAD;hpb=196c35ccc896c9c166619ef6baee88dcbb02727d

diff --git a/lurk.el b/lurk.el
index e519f46..52ee3b6 100644
--- a/lurk.el
+++ b/lurk.el
@@ -1,4 +1,4 @@
-;;; lurk.el --- Little Unified iRc Klient -*- lexical-binding:t -*-
+;;; lurk.el --- Little Unibuffer iRc Klient -*- lexical-binding:t -*-
 
 ;; Copyright (C) 2021 Tim Vaughan
 
@@ -35,76 +35,85 @@
 ;;
 
 (defgroup lurk nil
-  "Little Unified iRc Klient."
+  "Little Unibuffer 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-default-quit-msg "Bye"
+  "Default quit message when none supplied.")
 
 (defcustom lurk-networks
-  '(("libera" "irc.libera.chat" 6697)
-    ("freenode" "chat.freenode.net" 6697)
-    ("local" "localhost" 6697))
+  '(("libera" "irc.libera.chat" 6697))
   "IRC networks.")
 
 (defcustom lurk-allow-ipv6 nil
   "Set to non-nil to allow use of IPv6.")
 
+(defcustom lurk-show-joins nil
+  "Set to non-nil to be notified of joins, parts and quits.")
+
+(defcustom lurk-display-header t
+  "If non-nil, use buffer header to display information on current host and channel.")
+
 ;;; Faces
 ;;
 
 (defface lurk-text
-  '((t :inherit font-lock-preprocessor-face))
+  '((t :inherit default))
   "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))
+  '((t :inherit font-lock-keyword-face))
   "Face used for the prompt.")
 
 (defface lurk-context
-  '((t :inherit org-list-dt))
+  '((t :inherit lurk-context))
   "Face used for the context name in the prompt.")
 
 (defface lurk-faded
-  '((t :inherit font-lock-preprocessor-face))
+  '((t :inherit shadow))
   "Face used for faded Lurk text.")
 
-(defface lurk-bold
-  '((t :inherit font-lock-function-name-face))
-  "Face used for bold Lurk text.")
+(defface lurk-timestamp
+  '((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 warning))
+  "Face used for Lurk notice text.")
+
 ;;; Global variables
 ;;
 
-(defvar lurk-version "Lurk v0.1")
+(defvar lurk-version "Lurk v0.1"
+  "Value of this string is used in response to CTCP version queries.")
 
-(defvar lurk-notice-prefix
-  (concat
-   (propertize
-    "-" 'face 'lurk-faded)
-   (propertize
-    "!" 'face 'lurk-bold)
-   (propertize
-    "-" 'face 'lurk-faded)))
+(defvar lurk-notice-prefix "-!-")
 
-(defvar lurk-error-prefix
-  (propertize "!!!" 'face 'lurk-error))
+(defvar lurk-error-prefix "!!!")
 
+(defvar lurk-prompt-string ">")
 
-(defvar lurk-prompt-string
-  (propertize "> " 'face 'lurk-prompt))
+(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
@@ -122,7 +131,7 @@
   (unless (equal "open" (string-trim string))
     (lurk-display-error "Disconnected from server.")
     (clrhash lurk-contexts)
-    (setq lurk-current-context nil)
+    (lurk-set-current-context nil)
     (lurk-render-prompt)
     (cancel-timer lurk-ping-timer)))
 
@@ -159,14 +168,19 @@
     (if (not (assoc network lurk-networks))
         (lurk-display-error "Network '" network "' is unknown.")
       (clrhash lurk-contexts)
-      (setq lurk-current-context nil)
+      (lurk-set-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 "USER" lurk-nick 0 "*" lurk-nick))
       (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-connected-p ()
+  (let ((proc (get-process "lurk")))
+    (and proc (eq (process-status proc) 'open))))
 
 (defun lurk-send-msg (msg)
+  (if lurk-debug
+      (lurk-display-string nil nil (lurk-msg->string 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"))
@@ -177,11 +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)
@@ -230,9 +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))
@@ -265,10 +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)
@@ -280,6 +289,11 @@ portion of the source component of the message, as LURK doesn't use this.")
   (dolist (context (lurk-get-context-list))
     (lurk-del-context-user context user)))
 
+(defun lurk-rename-user (old-nick new-nick)
+  (dolist (context (lurk-get-context-list))
+    (lurk-del-context-user context old-nick)
+    (lurk-add-context-users context (list new-nick))))
+
 (defun lurk-get-context-type (name)
   (cond
    ((string-prefix-p "#" name) 'channel)
@@ -304,40 +318,22 @@ portion of the source component of the message, as LURK doesn't use this.")
           (car context-list)))
     nil))
 
+(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
-        (setq lurk-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.")))
 
-(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)))
@@ -359,6 +355,8 @@ portion of the source component of the message, as LURK doesn't use this.")
                        'read-only t)
            (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))
@@ -374,9 +372,31 @@ portion of the source component of the message, as LURK doesn't use this.")
 (defvar lurk-input-marker nil
   "Marker for prompt position in LURK buffer.")
 
+(defun lurk-setup-header ()
+  (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*")
     (setq-local scroll-conservatively 1)
+    (setq-local buffer-invisibility-spec nil)
     (if (markerp lurk-prompt-marker)
         (set-marker lurk-prompt-marker (point-max))
       (setq lurk-prompt-marker (point-max-marker)))
@@ -384,87 +404,315 @@ portion of the source component of the message, as LURK doesn't use this.")
         (set-marker lurk-input-marker (point-max))
       (setq lurk-input-marker (point-max-marker)))
     (goto-char (point-max))
-    (lurk-render-prompt)))
+    (lurk-render-prompt)
+    (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
+;;
 
-;;; Output formatting
+;; 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
+;; and for different elements of the context-specific text to have
+;; different styling.
+
+;; Additionally, we allow selective hiding of contexts via
+;; the buffer-invisibility-spec.
+
+(defvar lurk-context-facelists (make-hash-table :test 'equal)
+  "List of seen contexts and associated face lists.")
+
+(defun lurk-get-context-facelist (context)
+  (let ((facelist (gethash context lurk-context-facelists)))
+    (unless facelist
+      (setq facelist (list 'lurk-text))
+      (puthash context facelist lurk-context-facelists))
+    facelist))
+
+(defun lurk--fill-strings (col indent &rest strings)
+  (with-temp-buffer
+    (setq buffer-invisibility-spec nil)
+    (let ((fill-column col)
+          (adaptive-fill-regexp (rx-to-string `(= ,indent anychar))))
+      (apply #'insert strings)
+      (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 "*lurk*"
+    (save-excursion
+      (goto-char lurk-prompt-marker)
+      (let* ((inhibit-read-only t)
+             (old-pos (marker-position lurk-prompt-marker))
+             (padded-timestamp (concat (format-time-string "%H:%M ")))
+             (padded-prefix (if prefix (concat prefix " ") ""))
+             (context-atom (if context (intern context) nil)))
+        (insert-before-markers
+         (lurk--fill-strings
+          80
+          (+ (length padded-timestamp)
+             (length padded-prefix))
+          (propertize padded-timestamp
+                      'face 'lurk-timestamp
+                      'read-only t
+                      'context context
+                      'invisible context-atom)
+          (propertize padded-prefix
+                      '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))
                      to
                    (if (equal to lurk-nick) from to))))
     (lurk-display-string
+     context
      (propertize
       (pcase (lurk-get-context-type to)
-        ('channel (concat to " <" from "> " text))
-        ('nick (concat "[" from " -> " to "] " text))
+        ('channel (concat
+                   (lurk-make-context-button to)
+                   " <" from ">"))
+        ('nick (lurk-make-context-button context (concat "[" from " -> " to "]")))
         (_
          (error "Unsupported context type")))
-      'face 'lurk-text
-      'help-echo (concat "Context: " context)
-      'context context))))
+      'face (lurk-get-context-facelist context))
+     text)))
+
+(defun lurk-display-action (from to action-text)
+  (let ((context (if (eq 'channel (lurk-get-context-type to))
+                     to
+                   (if (equal to lurk-nick) from to))))
+    (lurk-display-string
+     context
+     (propertize
+      (concat (lurk-make-context-button context) " * " from)
+      'face (lurk-get-context-facelist context))
+     action-text)))
 
 (defun lurk-display-notice (context &rest notices)
   (lurk-display-string
-   (propertize
-    (concat lurk-notice-prefix " " (apply #'concat notices))
-    'help-echo (concat "Context: " (or context "none"))
-    'context context)))
+   context
+   (propertize lurk-notice-prefix 'face 'lurk-notice)
+   (apply #'concat notices)))
 
 (defun lurk-display-error (&rest messages)
   (lurk-display-string
-   (concat lurk-error-prefix " "
-           (propertize (apply #'concat messages)
-                       'face 'lurk-error))))
+   nil
+   (propertize lurk-error-prefix 'face 'lurk-error)
+   (apply #'concat messages)))
 
 (defun lurk-highlight-context (context)
+  (maphash
+   (lambda (this-context facelist)
+     (if (equal this-context context)
+         (setcar facelist 'lurk-text)
+       (setcar facelist 'lurk-faded)))
+   lurk-context-facelists)
+  (force-window-update "*lurk*"))
+
+(defun lurk-zoom-in (context)
+  (with-current-buffer "*lurk*"
+    (maphash
+     (lambda (this-context _)
+       (when this-context
+         (let ((this-context-atom (intern this-context)))
+           (if (equal this-context context)
+               (remove-from-invisibility-spec this-context-atom)
+             (add-to-invisibility-spec this-context-atom)))))
+     lurk-context-facelists)
+    (force-window-update "*lurk*"))
+  (lurk-scroll-windows-to-last-line))
+
+(defun lurk-zoom-out ()
   (with-current-buffer "*lurk*"
-    (let* ((pos lurk-prompt-marker)
-           (nextpos (previous-single-property-change pos 'context))
-           (inhibit-read-only t))
-      (while (> pos nextpos)
-        (let ((thiscontext (get-text-property nextpos 'context)))
-          (if thiscontext
-              (if (equal context thiscontext)
-                  (add-text-properties nextpos pos
-                                       '(face (foreground-color . "green")))
-                (add-text-properties nextpos pos
-                                     '(face (foreground-color . "blue"))))
-            (add-text-properties nextpos pos
-                                 '(face lurk-text)))
-          thiscontext
-          (setq pos nextpos)
-          (setq nextpos (previous-single-property-change pos 'context nil 1)))))))
+    (maphash
+     (lambda (this-context _)
+       (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*"))
+  (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 (:
+       (group (+ alpha))
+       "://"
+       (group (or (+ (any alnum "." "-"))
+                  (+ (any alnum ":"))))
+       (opt (group (: ":" (+ digit))))
+       (opt (group (: "/"
+                      (opt
+                       (* (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 (&rest strings)
+  "Turn substrings which look like urls in STRING into clickable buttons."
+  (with-temp-buffer
+    (apply #'insert strings)
+    (goto-char (point-min))
+    (while (re-search-forward lurk-url-regex nil t)
+      (let ((url (match-string 0)))
+        (make-text-button (match-beginning 0)
+                          (match-end 0)
+                          'action #'lurk-click-url
+                          'url url
+                          'follow-link t
+                          'face 'button
+                          '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
 ;;
 
 (defun lurk-eval-msg-string (string)
-  ;; (lurk-display-string string)
+  (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
         (lurk-msg nil nil "PONG" (lurk-msg-params msg))))
-       ;; (lurk-display-notice nil "ping-pong (server initiated)"))
 
       ("PONG")
-       ;; (lurk-display-notice nil "ping-pong (client initiated)"))
+
+      ("001"
+       (let* ((params (lurk-msg-params msg))
+              (nick (elt params 0))
+              (text (string-join (seq-drop params 1) " ")))
+         (setq lurk-nick nick)
+         (lurk-display-notice nil text)))
 
       ("353" ; NAMEREPLY
        (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)))
+         (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))
               (channel (elt params 1)))
          (lurk-display-notice
           channel
-          (lurk--as-string (length (lurk-get-context-users channel)))
-          " users in " channel)))
+          "No topic set.")))
+
+      ("332"
+       (let* ((params (lurk-msg-params msg))
+              (channel (elt params 1))
+              (topic (elt params 2)))
+         (lurk-display-notice channel "Topic: " topic)))
+
+      ("333") ; Avoid displaying these
 
       ((rx (= 3 (any digit)))
        (lurk-display-notice nil (mapconcat 'identity (cdr (lurk-msg-params msg)) " ")))
@@ -473,7 +721,7 @@ portion of the source component of the message, as LURK doesn't use this.")
             (guard (equal lurk-nick (lurk-msg-src msg))))
        (let ((channel (car (lurk-msg-params msg))))
          (lurk-add-context channel)
-         (setq lurk-current-context channel)
+         (lurk-set-current-context channel)
          (lurk-display-notice channel "Joining channel " channel)
          (lurk-render-prompt)))
 
@@ -481,7 +729,8 @@ portion of the source component of the message, as LURK doesn't use this.")
        (let ((channel (car (lurk-msg-params msg)))
              (nick (lurk-msg-src msg)))
          (lurk-add-context-users channel (list nick))
-         (lurk-display-notice channel nick " joined channel " channel)))
+         (if lurk-show-joins
+             (lurk-display-notice channel nick " joined channel " channel))))
 
       ((and "PART"
             (guard (equal lurk-nick (lurk-msg-src msg))))
@@ -489,20 +738,37 @@ portion of the source component of the message, as LURK doesn't use this.")
          (lurk-display-notice channel "Left channel " channel)
          (lurk-del-context channel)
          (if (equal channel lurk-current-context)
-             (setq lurk-current-context (lurk-get-next-context)))
+             (lurk-set-current-context (lurk-get-next-context)))
          (lurk-render-prompt)))
 
       ("PART"
        (let ((channel (car (lurk-msg-params msg)))
              (nick (lurk-msg-src msg)))
          (lurk-del-context-user channel nick)
-         (lurk-display-notice channel nick " left channel " channel)))
+         (if lurk-show-joins
+             (lurk-display-notice channel nick " left channel " channel))))
+
+      ((and "KICK")
+       (let ((kicker-nick (lurk-msg-src msg))
+             (channel (car (lurk-msg-params msg)))
+             (nick (cadr (lurk-msg-params msg)))
+             (reason (caddr (lurk-msg-params msg))))
+         (if (equal nick lurk-nick)
+             (progn
+               (lurk-display-notice channel kicker-nick " kicked you from " channel ": " reason)
+               (lurk-del-context channel)
+               (if (equal channel lurk-current-context)
+                   (lurk-set-current-context (lurk-get-next-context)))
+               (lurk-render-prompt))
+           (lurk-del-context-user channel nick)
+           (lurk-display-notice channel kicker-nick " kicked " nick " from " channel ": " reason))))
 
       ("QUIT"
        (let ((nick (lurk-msg-src msg))
              (reason (mapconcat 'identity (lurk-msg-params msg) " ")))
          (lurk-del-user nick)
-         (lurk-display-notice nil nick " quit: " reason)))
+         (if lurk-show-joins
+             (lurk-display-notice nil nick " quit: " reason))))
 
       ((and "NICK"
             (guard (equal lurk-nick (lurk-msg-src msg))))
@@ -512,8 +778,8 @@ portion of the source component of the message, as LURK doesn't use this.")
       ("NICK"
        (let ((old-nick (lurk-msg-src msg))
              (new-nick (car (lurk-msg-params msg))))
-         (lurk-display-notice nil nick " is now known as " new-nick)
-         (lurk-rename-user nick new-nick)))
+         (lurk-display-notice nil old-nick " is now known as " new-nick)
+         (lurk-rename-user old-nick new-nick)))
 
       ("NOTICE"
        (let ((nick (lurk-msg-src msg))
@@ -543,62 +809,258 @@ portion of the source component of the message, as LURK doesn't use this.")
 
            ((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))
+            (lurk-display-notice from "CTCP ping received from " from))
 
            ("\01USERINFO\01"
-            (lurk-display-notice "CTCP userinfo request from " from " (no response sent)"))
+            (lurk-display-notice from "CTCP userinfo request from " from " (no response sent)"))
+
+           ((rx (: "\01ACTION " (let action-text (* (not "\01"))) "\01"))
+            (lurk-display-action from to action-text))
 
            (_
             (lurk-display-message from to text)))))
       (_
-       (lurk-display-string (lurk-msg->string msg))))))
+       (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 (: "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))))
-         (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 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 "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
@@ -608,14 +1070,97 @@ 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.")))))
 
+
+;;; Command history
+;;
+
+(defvar lurk-history nil
+  "Commands and messages sent in current session.")
+
+(defvar lurk-history-index nil)
+
+(defun lurk-history-cycle (delta)
+  (when lurk-history
+    (with-current-buffer "*lurk*"
+      (if lurk-history-index
+          (setq lurk-history-index
+                (max 0
+                     (min (- (length lurk-history) 1)
+                          (+ delta lurk-history-index))))
+        (setq lurk-history-index 0))
+      (delete-region lurk-input-marker (point-max))
+      (insert (elt lurk-history lurk-history-index)))))
+
+
+;;; Interactive functions
+;;
+
+(defun lurk-cycle-contexts-forward ()
+  (interactive)
+  (lurk-cycle-contexts))
+
+(defun lurk-cycle-contexts-reverse ()
+  (interactive)
+  (lurk-cycle-contexts t))
+
+(defvar lurk-zoomed nil
+  "Keeps track of zoom status.")
+
+(defun lurk-toggle-zoom ()
+  (interactive)
+  (if lurk-zoomed
+      (lurk-zoom-out)
+    (lurk-zoom-in lurk-current-context))
+  (setq lurk-zoomed (not lurk-zoomed)))
+
+(defun lurk-history-next ()
+  (interactive)
+  (lurk-history-cycle -1))
+
+(defun lurk-history-prev ()
+  (interactive)
+  (lurk-history-cycle +1))
+
+(defun lurk-complete-input ()
+  (interactive)
+  (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*"
-    (lurk-enter-string
-     (buffer-substring lurk-input-marker (point-max)))
-    (let ((inhibit-read-only t))
-      (delete-region lurk-input-marker (point-max)))))
+    (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
@@ -624,8 +1169,15 @@ 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-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* 'motion map
+        (kbd "TAB") 'lurk-complete-input))
     map))
 
 (define-derived-mode lurk-mode text-mode "lurk"
@@ -634,19 +1186,22 @@ portion of the source component of the message, as LURK doesn't use this.")
 (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)
+    (switch-to-buffer "*lurk*")
+    (lurk-mode)
+    (lurk-setup-buffer)
+    (if network
+        (lurk-command-connect (list network))))
   "Started LURK.")
 
 
-
 ;;; lurk.el ends here