Replaced org-mode faces with font-lock/basic faces.

[elpher.git] / elpher.el

diff --git a/elpher.el b/elpher.el
index a55b659..fc18741 100644 (file)
--- a/elpher.el
+++ b/elpher.el
@@ -4,7 +4,7 @@
 
 ;; Author: Tim Vaughan <tgvaughan@gmail.com>
 ;; Created: 11 April 2019
 
 ;; Author: Tim Vaughan <tgvaughan@gmail.com>
 ;; Created: 11 April 2019

-;; Version: 1.0.0
+;; Version: 1.1.0

 ;; Keywords: comm gopher
 ;; Homepage: https://github.com/tgvaughan/elpher
 ;; Package-Requires: ((emacs "25"))
 ;; Keywords: comm gopher
 ;; Homepage: https://github.com/tgvaughan/elpher
 ;; Package-Requires: ((emacs "25"))


@@ -26,16 +26,36 @@
 
 ;;; Commentary:
 
 
 ;;; Commentary:
 

-;; Elpher is a tool for exploring "gopherspace" using GNU Emacs.
+;; Elpher aims to provide a full-featured gopher client for GNU Emacs.
+;; It supports:
+
+;; - intuitive keyboard and mouse-driven browsing,
+;; - caching of visited sites (both content and cursor position),
+;; - pleasant and configurable colouring of Gopher directories,
+;; - direct visualisation of image files,
+;; - (m)enu key support, similar to Emacs' info browser,
+;; - clickable web and gopher links in plain text.
+
+;; Visited pages are stored as a hierarchy rather than a linear history,
+;; meaning that navigation between these pages is quick and easy.
+
+;; To launch Elpher, simply use 'M-x elpher'.  This will open a start
+;; page containing information on key bindings and suggested starting
+;; points for your gopher exploration.
+
+;; Faces, caching options and start page can be configured via
+;; the Elpher customization group in Applications.

 
 ;;; Code:
 
 (provide 'elpher)
 
 ;;; Code:
 
 (provide 'elpher)

+(require 'seq)
+(require 'pp)

 
 ;;; Global constants
 ;;
 
 
 ;;; Global constants
 ;;
 

-(defconst elpher-version "1.0.0"
+(defconst elpher-version "1.1.0"

   "Current version of elpher.")
 
 (defconst elpher-margin-width 6
   "Current version of elpher.")
 
 (defconst elpher-margin-width 6


@@ -45,17 +65,21 @@
   (mapconcat
    'identity
    (list "i\tfake\tfake\t1"
   (mapconcat
    'identity
    (list "i\tfake\tfake\t1"

-         "i--------------------------------------------\tfake\tfake\t1"
-         "i           Elpher Gopher Client             \tfake\tfake\t1"
-         (format "i              version %s\tfake\tfake\t1" elpher-version)
-         "i--------------------------------------------\tfake\tfake\t1"
+         "i     --------------------------------------------\tfake\tfake\t1"
+         "i                Elpher Gopher Client             \tfake\tfake\t1"
+         (format "i                   version %s\tfake\tfake\t1" elpher-version)
+         "i     --------------------------------------------\tfake\tfake\t1"

          "i\tfake\tfake\t1"
          "i\tfake\tfake\t1"

-         "iBasic usage:\tfake\tfake\t1"
+         "iUsage:\tfake\tfake\t1"

          "i\tfake\tfake\t1"
          "i\tfake\tfake\t1"

-         "i - tab/shift-tab: next/prev directory entry on current page\tfake\tfake\t1"
-         "i - RET/mouse-1: open directory entry under cursor\tfake\tfake\t1"
-         "i - u: return to parent directory entry\tfake\tfake\t1"
-         "i - g: go to a particular page\tfake\tfake\t1"
+         "i - tab/shift-tab: next/prev item on current page\tfake\tfake\t1"
+         "i - RET/mouse-1: open item under cursor\tfake\tfake\t1"
+         "i - m: select an item on current page by name (autocompletes)\tfake\tfake\t1"
+         "i - u: return to parent\tfake\tfake\t1"
+         "i - O: visit the root menu of the current server\tfake\tfake\t1"
+         "i - g: go to a particular menu or item\tfake\tfake\t1"
+         "i - i/I: info on item under cursor or current page\tfake\tfake\t1"
+         "i - c/C: copy URL representation of item under cursor or current page\tfake\tfake\t1"

          "i - r: redraw current page (using cached contents if available)\tfake\tfake\t1"
          "i - R: reload current page (regenerates cache)\tfake\tfake\t1"
          "i - d: download directory entry under cursor\tfake\tfake\t1"
          "i - r: redraw current page (using cached contents if available)\tfake\tfake\t1"
          "i - R: reload current page (regenerates cache)\tfake\tfake\t1"
          "i - d: download directory entry under cursor\tfake\tfake\t1"


@@ -69,10 +93,24 @@
          "isearch terms:\tfake\tfake\t1"
          "i\tfake\tfake\t1"
          "7Veronica-2 Gopher Search Engine\t/v2/vs\tgopher.floodgap.com\t70"
          "isearch terms:\tfake\tfake\t1"
          "i\tfake\tfake\t1"
          "7Veronica-2 Gopher Search Engine\t/v2/vs\tgopher.floodgap.com\t70"

-         ".")
+         ".\r\n")

    "\r\n")
   "Source for elpher start page.")
 
    "\r\n")
   "Source for elpher start page.")
 

+(defconst elpher-type-map
+  '((?0 elpher-get-text-node "T" elpher-text)
+    (?1 elpher-get-index-node "/" elpher-index)
+    (?4 elpher-get-node-download "B" elpher-binary)
+    (?5 elpher-get-node-download "B" elpher-binary)
+    (?7 elpher-get-search-node "?" elpher-search)
+    (?8 elpher-get-telnet-node "?" elpher-telnet)
+    (?9 elpher-get-node-download "B" elpher-binary)
+    (?g elpher-get-image-node "im" elpher-image)
+    (?p elpher-get-image-node "im" elpher-image)
+    (?I elpher-get-image-node "im" elpher-image)
+    (?h elpher-get-url-node "W" elpher-url))
+  "Association list from types to getters, margin codes and index faces.")
+

 
 ;;; Customization group
 ;;
 
 ;;; Customization group
 ;;


@@ -81,103 +119,126 @@
   "A gopher client."
   :group 'applications)
 
   "A gopher client."
   :group 'applications)
 

+;; Face customizations
+

 (defface elpher-index
 (defface elpher-index

-  '((((background dark)) :foreground "deep sky blue")
-    (((background light)) :foreground "blue"))
-  "Face used for index records.")
+  '((t :inherit font-lock-keyword-face))
+  "Face used for directory type directory records.")

 
 (defface elpher-text
 
 (defface elpher-text

-  '((((background dark)) :foreground "white")
-    (((background light)) :weight bold))
-  "Face used for text records.")
+  '((t :inherit bold))
+  "Face used for text type directory records.")

 
 

-(defface elpher-info '()
-  "Face used for info records.")
+(defface elpher-info
+  '((t :inherit default))
+  "Face used for info type directory records.")

 
 (defface elpher-image
 
 (defface elpher-image

-  '((((background dark)) :foreground "green")
-    (t :foreground "dark green"))
-  "Face used for image records.")
+  '((t :inherit font-lock-string-face))
+  "Face used for image type directory records.")

 
 (defface elpher-search
 
 (defface elpher-search

-  '((((background light)) :foreground "orange")
-    (((background dark)) :foreground "dark orange"))
-  "Face used for search records.")
+  '((t :inherit warning))
+  "Face used for search type directory records.")

 
 (defface elpher-url
 
 (defface elpher-url

-  '((((background dark)) :foreground "yellow")
-    (((background light)) :foreground "dark red"))
-  "Face used for url records.")
+  '((t :inherit font-lock-comment-face))
+  "Face used for url type directory records.")
+
+(defface elpher-telnet
+  '((t :inherit font-lock-function-name-face))
+  "Face used for telnet type directory records.")

 
 (defface elpher-binary
 
 (defface elpher-binary

-  '((t :foreground "magenta"))
-  "Face used for binary records.")
+  '((t :inherit font-lock-doc-face))
+  "Face used for binary type directory records.")

 
 (defface elpher-unknown
 
 (defface elpher-unknown

-  '((t :foreground "red"))
-  "Face used for unknown record types.")
+  '((t :inherit error))
+  "Face used for directory records with unknown/unsupported types.")

 
 (defface elpher-margin-key
 
 (defface elpher-margin-key

-  '((((background dark)) :foreground "white"))
-  "Face used for margin key.")
+  '((t :inherit bold))
+  "Face used for directory margin key.")

 
 (defface elpher-margin-brackets
 
 (defface elpher-margin-brackets

-  '((t :foreground "blue"))
-  "Face used for brackets around margin key.")
+  '((t :inherit shadow))
+  "Face used for brackets around directory margin key.")
+
+;; Other customizations

 
 (defcustom elpher-open-urls-with-eww nil
   "If non-nil, open URL selectors using eww.
 Otherwise, use the system browser via the BROWSE-URL function."
   :type '(boolean))
 
 
 (defcustom elpher-open-urls-with-eww nil
   "If non-nil, open URL selectors using eww.
 Otherwise, use the system browser via the BROWSE-URL function."
   :type '(boolean))
 

+(defcustom elpher-buttonify-urls-in-directories nil
+  "If non-nil, turns URLs matched in directories into clickable buttons."
+  :type '(boolean))
+

 (defcustom elpher-cache-images nil
   "If non-nil, cache images in memory in the same way as other content."
   :type '(boolean))
 
 (defcustom elpher-cache-images nil
   "If non-nil, cache images in memory in the same way as other content."
   :type '(boolean))
 

+(defcustom elpher-start-address nil
+  "If nil, the default start directory is shown when Elpher is started.
+Otherwise, a list containing the selector, host and port of a directory to
+use as the start page."
+  :type '(list string string integer))
+
+(defcustom elpher-use-header t
+  "If non-nil, display current node information in buffer header."
+  :type '(boolean))
+

 ;;; Model
 ;;
 
 ;; Address
 
 ;;; Model
 ;;
 
 ;; Address
 

-(defun elpher-make-address (selector host port)
-  "Create an address of a gopher object with SELECTOR, HOST and PORT."
-  (list selector host port))
+(defun elpher-make-address (type selector host port)
+  "Create an address of a gopher object with TYPE, SELECTOR, HOST and PORT."
+  (list type selector host port))
+
+(defun elpher-address-type (address)
+  "Retrieve type from ADDRESS."
+  (elt address 0))

 
 (defun elpher-address-selector (address)
   "Retrieve selector from ADDRESS."
 
 (defun elpher-address-selector (address)
   "Retrieve selector from ADDRESS."

-  (car address))
+  (elt address 1))

 
 (defun elpher-address-host (address)
   "Retrieve host from ADDRESS."
 
 (defun elpher-address-host (address)
   "Retrieve host from ADDRESS."

-  (cadr address))
+  (elt address 2))

 
 (defun elpher-address-port (address)
   "Retrieve port from ADDRESS."
 
 (defun elpher-address-port (address)
   "Retrieve port from ADDRESS."

-  (caddr address))
+  (elt address 3))

 
 ;; Node
 
 
 ;; Node
 

-(defun elpher-make-node (parent address getter &optional content pos)
+(defun elpher-make-node (display-string parent address &optional content pos)

   "Create a node in the gopher page hierarchy.
 
   "Create a node in the gopher page hierarchy.
 

-PARENT specifies the parent of the node, ADDRESS specifies the address of
-the gopher page, GETTER provides the getter function used to obtain this
-page.
+DISPLAY-STRING records the display string used for the page.
+
+PARENT specifies the parent of the node, and ADDRESS specifies the
+address of the gopher page.

 
 The optional arguments CONTENT and POS can be used to fill the cached
 content and cursor position fields of the node."
 
 The optional arguments CONTENT and POS can be used to fill the cached
 content and cursor position fields of the node."

-  (list parent address getter content pos))
+  (list display-string parent address content pos))
+
+(defun elpher-node-display-string (node)
+  "Retrieve the display string of NODE."
+  (elt node 0))

 
 (defun elpher-node-parent (node)
   "Retrieve the parent node of NODE."
 
 (defun elpher-node-parent (node)
   "Retrieve the parent node of NODE."

-  (elt node 0))
+  (elt node 1))

 
 (defun elpher-node-address (node)
   "Retrieve the address of NODE."
 
 (defun elpher-node-address (node)
   "Retrieve the address of NODE."

-  (elt node 1))
-
-(defun elpher-node-getter (node)
-  "Retrieve the preferred getter function of NODE."

   (elt node 2))
 
 (defun elpher-node-content (node)
   (elt node 2))
 
 (defun elpher-node-content (node)


@@ -198,16 +259,25 @@ content and cursor position fields of the node."
 
 ;; Node graph traversal
 
 
 ;; Node graph traversal
 

-(defvar elpher-current-node)
+(defvar elpher-current-node nil)

 
 (defun elpher-visit-node (node &optional getter)
   "Visit NODE using its own getter or GETTER, if non-nil."
   (elpher-save-pos)
   (elpher-process-cleanup)
   (setq elpher-current-node node)
 
 (defun elpher-visit-node (node &optional getter)
   "Visit NODE using its own getter or GETTER, if non-nil."
   (elpher-save-pos)
   (elpher-process-cleanup)
   (setq elpher-current-node node)

+  (with-current-buffer "*elpher*"
+    (setq header-line-format "hello"))
+    ;; (let ((inhibit-read-only t))
+
+    ;; (force-mode-line-update))

   (if getter
       (funcall getter)
   (if getter
       (funcall getter)

-    (funcall (elpher-node-getter node))))
+    (let* ((address (elpher-node-address node))
+           (type (if address
+                     (elpher-address-type address)
+                   ?1)))
+      (funcall (car (alist-get type elpher-type-map))))))

 
 (defun elpher-visit-parent-node ()
   "Visit the parent of the current node."
 
 (defun elpher-visit-parent-node ()
   "Visit the parent of the current node."


@@ -232,26 +302,55 @@ content and cursor position fields of the node."
         (goto-char pos)
       (goto-char (point-min)))))
 
         (goto-char pos)
       (goto-char (point-min)))))
 

+

 ;;; Buffer preparation
 ;;
 
 ;;; Buffer preparation
 ;;
 

+(defun elpher-update-header ()
+  "If `elpher-use-header' is true, display current node info in window header."
+  (if elpher-use-header
+      (setq header-line-format (elpher-node-display-string elpher-current-node))))
+

 (defmacro elpher-with-clean-buffer (&rest args)
   "Evaluate ARGS with a clean *elpher* buffer as current."
 (defmacro elpher-with-clean-buffer (&rest args)
   "Evaluate ARGS with a clean *elpher* buffer as current."

-  (list 'progn
-        '(switch-to-buffer "*elpher*")
+  (list 'with-current-buffer "*elpher*"

         '(elpher-mode)
         (append (list 'let '((inhibit-read-only t))
         '(elpher-mode)
         (append (list 'let '((inhibit-read-only t))

-                      '(erase-buffer))
+                      '(erase-buffer)
+                      '(elpher-update-header))

                 args)))
 
                 args)))
 

+

 ;;; Index rendering
 ;;
 
 ;;; Index rendering
 ;;
 

+(defun elpher-preprocess-text-response (string)
+  "Clear away CRs and terminating period from STRING."
+  (replace-regexp-in-string "\n\.\n$" "\n"
+                            (replace-regexp-in-string "\r" ""
+                                                      string)))
+

 (defun elpher-insert-index (string)
   "Insert the index corresponding to STRING into the current buffer."
 (defun elpher-insert-index (string)
   "Insert the index corresponding to STRING into the current buffer."

-  (dolist (line (split-string string "\r\n"))
-    (unless (= (length line) 0)
-      (elpher-insert-index-record line))))
+  ;; Should be able to split directly on CRLF, but some non-conformant
+  ;; LF-only servers sadly exist, hence the following.
+  (let ((str-processed (elpher-preprocess-text-response string))
+        formatting-error)
+    (dolist (line (split-string str-processed "\n"))
+      (unless (= (length line) 0)
+        (let* ((type (elt line 0))
+               (fields (split-string (substring line 1) "\t"))
+               (display-string (elt fields 0))
+               (selector (elt fields 1))
+               (host (elt fields 2))
+               (port (if (elt fields 3)
+                         (string-to-number (elt fields 3))
+                       nil)))
+          (if (< (length fields) 4)
+              (setq formatting-error t))
+          (elpher-insert-index-record display-string type selector host port))))
+    (if formatting-error
+        (display-warning :warning "One or more badly formatted index records detected."))))

 
 (defun elpher-insert-margin (&optional type-name)
   "Insert index margin, optionally containing the TYPE-NAME, into the current buffer."
 
 (defun elpher-insert-margin (&optional type-name)
   "Insert index margin, optionally containing the TYPE-NAME, into the current buffer."


@@ -265,60 +364,53 @@ content and cursor position fields of the node."
         (insert " "))
     (insert (make-string elpher-margin-width ?\s))))
 
         (insert " "))
     (insert (make-string elpher-margin-width ?\s))))
 

-(defvar elpher-type-map
-  '((?0 elpher-get-text-node "T" elpher-text)
-    (?1 elpher-get-index-node "/" elpher-index)
-    (?g elpher-get-image-node "im" elpher-image)
-    (?p elpher-get-image-node "im" elpher-image)
-    (?I elpher-get-image-node "im" elpher-image)
-    (?4 elpher-get-node-download "B" elpher-binary)
-    (?5 elpher-get-node-download "B" elpher-binary)
-    (?9 elpher-get-node-download "B" elpher-binary)
-    (?7 elpher-get-search-node "?" elpher-search))
-  "Association list from types to getters, margin codes and index faces.")
-
-(defun elpher-insert-index-record (line)
-  "Insert the index record corresponding to LINE into the current buffer."
-  (let* ((type (elt line 0))
-         (fields (split-string (substring line 1) "\t"))
-         (display-string (elt fields 0))
-         (selector (elt fields 1))
-         (host (elt fields 2))
-         (port (elt fields 3))
-         (address (elpher-make-address selector host port))
-         (type-map-entry (alist-get type elpher-type-map)))
+(defun elpher-node-button-help (node)
+  "Return a string containing the help text for a button corresponding to NODE."
+  (let ((address (elpher-node-address node)))
+    (if (eq (elpher-address-type address) ?h)
+        (let ((url (cadr (split-string (elpher-address-selector address) "URL:"))))
+          (format "mouse-1, RET: open url '%s'" url))
+      (format "mouse-1, RET: open '%s' on %s port %s"
+              (elpher-address-selector address)
+              (elpher-address-host address)
+              (elpher-address-port address)))))
+
+(defun elpher-insert-index-record (display-string type selector host port)
+  "Function to insert an index record into the current buffer.
+The contents of the record are dictated by TYPE, DISPLAY-STRING, SELECTOR, HOST
+and PORT."
+  (let ((address (elpher-make-address type selector host port))
+        (type-map-entry (alist-get type elpher-type-map)))

     (if type-map-entry
     (if type-map-entry

-        (let ((getter (car type-map-entry))
-              (margin-code (cadr type-map-entry))
-              (face (caddr type-map-entry)))
+        (let* ((margin-code (cadr type-map-entry))
+               (face (caddr type-map-entry))
+               (node (elpher-make-node display-string elpher-current-node address)))

           (elpher-insert-margin margin-code)
           (insert-text-button display-string
                               'face face
           (elpher-insert-margin margin-code)
           (insert-text-button display-string
                               'face face

-                              'elpher-node (elpher-make-node elpher-current-node
-                                                               address
-                                                               getter)
+                              'elpher-node node

                               'action #'elpher-click-link
                               'follow-link t
                               'action #'elpher-click-link
                               'follow-link t

-                              'help-echo (format "mouse-1, RET: open %s on %s port %s"
-                                                 selector host port)))
+                              'help-echo (elpher-node-button-help node)))

       (pcase type
       (pcase type

-        (?i (elpher-insert-margin) ; Information
-            (insert (propertize display-string
-                                'face 'elpher-info)))
-        (?h (elpher-insert-margin "W") ; Web link
-            (let ((url (elt (split-string selector "URL:") 1)))
-              (insert-text-button display-string
-                                  'face 'elpher-url
-                                  'elpher-url url
-                                  'action #'elpher-click-url
-                                  'follow-link t
-                                  'help-echo (format "mouse-1, RET: open url %s" url))))
-        (?.) ; Occurs at end of index, can safely ignore.
-        (tp (elpher-insert-margin (concat (char-to-string tp) "?"))
-            (insert (propertize display-string
-                                'face 'elpher-unknown-face)))))
+        (?i ;; Information
+         (elpher-insert-margin)
+         (insert (propertize
+                  (if elpher-buttonify-urls-in-directories
+                      (elpher-buttonify-urls display-string)
+                    display-string)
+                  'face 'elpher-info)))
+        (other ;; Unknown
+         (elpher-insert-margin (concat (char-to-string type) "?"))
+         (insert (propertize display-string
+                             'face 'elpher-unknown-face)))))

     (insert "\n")))
 
     (insert "\n")))
 

+(defun elpher-click-link (button)
+  "Function called when the gopher link BUTTON is activated (via mouse or keypress)."
+  (let ((node (button-get button 'elpher-node)))
+    (elpher-visit-node node)))
+

 
 ;;; Selector retrieval (all kinds)
 ;;
 
 ;;; Selector retrieval (all kinds)
 ;;


@@ -353,8 +445,8 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
     (if content
         (progn
           (elpher-with-clean-buffer
     (if content
         (progn
           (elpher-with-clean-buffer

-           (insert content))
-          (elpher-restore-pos))
+           (insert content)
+           (elpher-restore-pos)))

       (if address
           (progn
             (elpher-with-clean-buffer
       (if address
           (progn
             (elpher-with-clean-buffer


@@ -363,66 +455,70 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
                                   (lambda (proc event)
                                     (unless (string-prefix-p "deleted" event)
                                       (elpher-with-clean-buffer
                                   (lambda (proc event)
                                     (unless (string-prefix-p "deleted" event)
                                       (elpher-with-clean-buffer

-                                       (elpher-insert-index elpher-selector-string))
-                                      (elpher-restore-pos)
-                                      (elpher-set-node-content elpher-current-node
-                                                                (buffer-string))))))
+                                       (elpher-insert-index elpher-selector-string)
+                                       (elpher-restore-pos)
+                                       (elpher-set-node-content elpher-current-node
+                                                                (buffer-string)))))))

         (progn
           (elpher-with-clean-buffer
         (progn
           (elpher-with-clean-buffer

-           (elpher-insert-index elpher-start-index))
-          (elpher-restore-pos)
-          (elpher-set-node-content elpher-current-node
-                                    (buffer-string)))))))
+           (elpher-insert-index elpher-start-index)
+           (elpher-restore-pos)
+           (elpher-set-node-content elpher-current-node
+                                    (buffer-string))))))))

 
 ;; Text retrieval
 
 (defconst elpher-url-regex
 
 ;; Text retrieval
 
 (defconst elpher-url-regex

-  "\\(https?\\|gopher\\)://\\([a-zA-Z0-9.\-]+\\)\\(?3::[0-9]+\\)?\\(?4:/[^ \r\n\t(),]*\\)?"
+  "\\([a-zA-Z]+\\)://\\([a-zA-Z0-9.\-]+\\)\\(?3::[0-9]+\\)?\\(?4:/[^ \r\n\t(),]*\\)?"

   "Regexp used to locate and buttinofy URLs in text files loaded by elpher.")
 
   "Regexp used to locate and buttinofy URLs in text files loaded by elpher.")
 

+(defun elpher-make-node-from-matched-url (parent &optional string)
+  "Convert most recent `elpher-url-regex' match to a node.
+
+PARENT defines the node to set as the parent to the new node.
+
+If STRING is non-nil, this is given as an argument to all `match-string'
+calls, as is necessary if the match is performed by `string-match'."
+  (let ((url (match-string 0 string))
+        (protocol (downcase (match-string 1 string))))
+    (if (string= protocol "gopher")
+        (let* ((host (match-string 2 string))
+               (port (if (> (length (match-string 3 string))  1)
+                         (string-to-number (substring (match-string 3 string) 1))
+                       70))
+               (type-and-selector (match-string 4 string))
+               (type (if (> (length type-and-selector) 1)
+                         (elt type-and-selector 1)
+                       ?1))
+               (selector (if (> (length type-and-selector) 1)
+                             (substring type-and-selector 2)
+                           ""))
+               (address (elpher-make-address type selector host port)))
+          (elpher-make-node url elpher-current-node address))
+      (let* ((host (match-string 2 string))
+             (port (if (> (length (match-string 3 string)) 1)
+                       (string-to-number (substring (match-string 3 string) 1))
+                     70))
+             (selector (concat "URL:" url))
+             (address (elpher-make-address ?h selector host port)))
+        (elpher-make-node url elpher-current-node address)))))
+
+

 (defun elpher-buttonify-urls (string)
   "Turn substrings which look like urls in STRING into clickable buttons."
   (with-temp-buffer
     (insert string)
     (goto-char (point-min))
     (while (re-search-forward elpher-url-regex nil t)
 (defun elpher-buttonify-urls (string)
   "Turn substrings which look like urls in STRING into clickable buttons."
   (with-temp-buffer
     (insert string)
     (goto-char (point-min))
     (while (re-search-forward elpher-url-regex nil t)

-      (let ((url (match-string 0))
-            (protocol (downcase (match-string 1))))
-        (if (string= protocol "gopher")
-            (let* ((host (match-string 2))
-                   (port 70)
-                   (type-and-selector (match-string 4))
-                   (type (if (> (length type-and-selector) 1)
-                             (elt type-and-selector 1)
-                           ?1))
-                   (selector (if (> (length type-and-selector) 1)
-                                 (substring type-and-selector 2)
-                               ""))
-                   (address (elpher-make-address selector host port))
-                   (getter (car (alist-get type elpher-type-map))))
-              (make-text-button (match-beginning 0)
-                                (match-end 0)
-                                'elpher-node (elpher-make-node elpher-current-node
-                                                                 address
-                                                                 getter)
-                                'action #'elpher-click-link
-                                'follow-link t
-                                'help-echo (format "mouse-1, RET: open %s on %s port %s"
-                                                   selector host port)))
+        (let ((node (elpher-make-node-from-matched-url elpher-current-node)))

           (make-text-button (match-beginning 0)
                             (match-end 0)
           (make-text-button (match-beginning 0)
                             (match-end 0)

-                            'elpher-url url
-                            'action #'elpher-click-url
+                            'elpher-node  node
+                            'action #'elpher-click-link

                             'follow-link t
                             'follow-link t

-                            'help-echo (format "mouse-1, RET: open url %s" url)))))
+                            'help-echo (elpher-node-button-help node))))

     (buffer-string)))
 
     (buffer-string)))
 

-(defun elpher-process-text (string)
-  "Remove CRs and trailing period from the gopher text document STRING."
-  (let* ((chopped-str (replace-regexp-in-string "\r\n\.\r\n$" "\r\n" string))
-         (cleaned-str (replace-regexp-in-string "\r" "" chopped-str)))
-    (elpher-buttonify-urls cleaned-str)))
-

 (defun elpher-get-text-node ()
   "Getter which retrieves the current node contents as a text document."
   (let ((content (elpher-node-content elpher-current-node))
 (defun elpher-get-text-node ()
   "Getter which retrieves the current node contents as a text document."
   (let ((content (elpher-node-content elpher-current-node))


@@ -430,8 +526,8 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
     (if content
         (progn
           (elpher-with-clean-buffer
     (if content
         (progn
           (elpher-with-clean-buffer

-           (insert content))
-          (elpher-restore-pos))
+           (insert content)
+           (elpher-restore-pos)))

       (progn
         (elpher-with-clean-buffer
          (insert "LOADING TEXT..."))
       (progn
         (elpher-with-clean-buffer
          (insert "LOADING TEXT..."))


@@ -439,10 +535,12 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
                               (lambda (proc event)
                                 (unless (string-prefix-p "deleted" event)
                                   (elpher-with-clean-buffer
                               (lambda (proc event)
                                 (unless (string-prefix-p "deleted" event)
                                   (elpher-with-clean-buffer

-                                   (insert (elpher-process-text elpher-selector-string)))
-                                  (elpher-restore-pos)
-                                  (elpher-set-node-content elpher-current-node
-                                                            (buffer-string)))))))))
+                                   (insert (elpher-buttonify-urls
+                                            (elpher-preprocess-text-response
+                                             elpher-selector-string)))
+                                   (elpher-restore-pos)
+                                   (elpher-set-node-content elpher-current-node
+                                                            (buffer-string))))))))))

 
 ;; Image retrieval
 
 
 ;; Image retrieval
 


@@ -453,9 +551,8 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
     (if content
         (progn
           (elpher-with-clean-buffer
     (if content
         (progn
           (elpher-with-clean-buffer

-           (insert-image content))
-          (setq cursor-type nil)
-          (elpher-restore-pos))
+           (insert-image content)
+           (elpher-restore-pos)))

       (if (display-images-p)
           (progn
             (elpher-with-clean-buffer
       (if (display-images-p)
           (progn
             (elpher-with-clean-buffer


@@ -464,13 +561,13 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
                                  (lambda (proc event)
                                    (unless (string-prefix-p "deleted" event)
                                      (let ((image (create-image
                                  (lambda (proc event)
                                    (unless (string-prefix-p "deleted" event)
                                      (let ((image (create-image

-                                                   (encode-coding-string elpher-selector-string
-                                                                         'no-conversion)
+                                                   (encode-coding-string
+                                                    elpher-selector-string
+                                                    'no-conversion)

                                                    nil t)))
                                        (elpher-with-clean-buffer
                                                    nil t)))
                                        (elpher-with-clean-buffer

-                                        (insert-image image))
-                                       (setq cursor-type nil)
-                                       (elpher-restore-pos)
+                                        (insert-image image)
+                                        (elpher-restore-pos))

                                        (if elpher-cache-images
                                            (elpher-set-node-content elpher-current-node
                                                                     image)))))))
                                        (if elpher-cache-images
                                            (elpher-set-node-content elpher-current-node
                                                                     image)))))))


@@ -486,15 +583,16 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
     (if content
         (progn
           (elpher-with-clean-buffer
     (if content
         (progn
           (elpher-with-clean-buffer

-           (insert content))
-          (elpher-restore-pos)
+           (insert content)
+           (elpher-restore-pos))

           (message "Displaying cached search results.  Reload to perform a new search."))
       (unwind-protect
           (let* ((query-string (read-string "Query: "))
                  (query-selector (concat (elpher-address-selector address) "\t" query-string))
           (message "Displaying cached search results.  Reload to perform a new search."))
       (unwind-protect
           (let* ((query-string (read-string "Query: "))
                  (query-selector (concat (elpher-address-selector address) "\t" query-string))

-                 (search-address (elpher-make-address query-selector
-                                                       (elpher-address-host address)
-                                                       (elpher-address-port address))))
+                 (search-address (elpher-make-address ?1
+                                                      query-selector
+                                                      (elpher-address-host address)
+                                                      (elpher-address-port address))))

             (setq aborted nil)
             (elpher-with-clean-buffer
              (insert "LOADING RESULTS..."))
             (setq aborted nil)
             (elpher-with-clean-buffer
              (insert "LOADING RESULTS..."))


@@ -522,8 +620,8 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
                               (lambda (proc event)
                                 (unless (string-prefix-p "deleted" event)
                                   (elpher-with-clean-buffer
                               (lambda (proc event)
                                 (unless (string-prefix-p "deleted" event)
                                   (elpher-with-clean-buffer

-                                   (insert elpher-selector-string))
-                                  (goto-char (point-min)))))
+                                   (insert elpher-selector-string)
+                                   (goto-char (point-min))))))

       (progn
         (elpher-with-clean-buffer
          (insert elpher-start-index))
       (progn
         (elpher-with-clean-buffer
          (insert elpher-start-index))


@@ -555,8 +653,126 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
                                   (message (format "Download complate, saved to file %s."
                                                    elpher-download-filename)))))))))
 
                                   (message (format "Download complate, saved to file %s."
                                                    elpher-download-filename)))))))))
 

+;; URL retrieval
+
+(defun elpher-get-url-node ()
+  "Getter which attempts to open the URL specified by the current node."
+  (let* ((address (elpher-node-address elpher-current-node))
+         (selector (elpher-address-selector address)))
+    (elpher-visit-parent-node) ; Do first in case of non-local exits.
+    (let ((url (elt (split-string selector "URL:") 1)))
+      (if elpher-open-urls-with-eww
+          (browse-web url)
+        (browse-url url)))))
+
+;; Telnet node connection
+
+(defun elpher-get-telnet-node ()
+  "Getter which opens a telnet connection to the server specified by the current node."
+  (let* ((address (elpher-node-address elpher-current-node))
+         (host (elpher-address-host address))
+         (port (elpher-address-port address)))
+    (elpher-visit-parent-node)
+    (telnet host port)))
+
+
+;;; Bookmarks
+;;
+
+(defun elpher-make-bookmark (display-string address)
+  "Make an elpher bookmark.
+DISPLAY-STRING determines how the bookmark will appear in the
+bookmark list, while ADDRESS is the address of the entry."
+  (list display-string address))
+  
+(defun elpher-bookmark-display-string (bookmark)
+  "Get the display string of BOOKMARK."
+  (elt bookmark 0))
+
+(defun elpher-bookmark-address (bookmark)
+  "Get the address for BOOKMARK."
+  (elt bookmark 1))
+
+(defun elpher-save-bookmarks (bookmarks)
+  "Record the bookmark list BOOKMARKS to the user's bookmark file.
+Beware that this completely replaces the existing contents of the file."
+  (with-temp-file (locate-user-emacs-file "elpher-bookmarks")
+    (erase-buffer)
+    (pp bookmarks (current-buffer))))
+
+(defun elpher-load-bookmarks ()
+  "Get the list of bookmarks from the users's bookmark file."
+  (with-temp-buffer
+    (ignore-errors
+      (insert-file-contents (locate-user-emacs-file "elpher-bookmarks"))
+      (goto-char (point-min))
+      (read (current-buffer)))))
+
+(defun elpher-add-node-bookmark (node)
+  "Add bookmark to NODE to the saved list of bookmarks."
+  (let ((bookmark (elpher-make-bookmark (elpher-node-display-string node)
+                                        (elpher-node-address node)))
+        (bookmarks (elpher-load-bookmarks)))
+    (add-to-list 'bookmarks bookmark)
+    (elpher-save-bookmarks bookmarks)))
+
+(defun elpher-remove-node-bookmark (node)
+  "Remove bookmark to NODE from the saved list of bookmarks."
+  (let ((bookmark (elpher-make-bookmark (elpher-node-display-string node)
+                                        (elpher-node-address node))))
+    (elpher-save-bookmarks
+     (seq-filter (lambda (this-bookmark)
+                   (not (equal bookmark this-bookmark)))
+                 (elpher-load-bookmarks)))))
+     
+(defun elpher-display-bookmarks ()
+  "Display saved bookmark list."
+  (interactive)
+  (elpher-with-clean-buffer
+   (insert "Use 'r' to return to the previous page.\n\n"
+           "---- Bookmark list ----\n\n")
+   (let ((bookmarks (elpher-load-bookmarks)))
+     (if bookmarks
+         (dolist (bookmark bookmarks)
+           (let ((display-string (elpher-bookmark-display-string bookmark))
+                 (address (elpher-bookmark-address bookmark)))
+             (elpher-insert-index-record display-string
+                                         (elpher-address-type address)
+                                         (elpher-address-selector address)
+                                         (elpher-address-host address)
+                                         (elpher-address-port address))))
+       (insert "No bookmarks found.\n")))
+   (insert "\n-----------------------")
+   (goto-char (point-min))
+   (elpher-next-link)))
+
+(defun elpher-bookmark-current ()
+  "Bookmark the current node."
+  (interactive)
+  (elpher-add-node-bookmark elpher-current-node))
+
+(defun elpher-bookmark-link ()
+  "Bookmark the link at point."
+  (interactive)
+  (let ((button (button-at (point))))
+    (if button
+        (elpher-add-node-bookmark (button-get button 'elpher-node))
+      (error "No link selected"))))
+
+(defun elpher-unbookmark-current ()
+  "Remove bookmark for the current node."
+  (interactive)
+  (elpher-remove-node-bookmark elpher-current-node))
+
+(defun elpher-unbookmark-link ()
+  "Remove bookmark for the link at point."
+  (interactive)
+  (let ((button (button-at (point))))
+    (if button
+        (elpher-remove-node-bookmark (button-get button 'elpher-node))
+      (error "No link selected"))))

 
 

-;;; Navigation procedures
+;;; Interactive navigation procedures

 ;;
 
 (defun elpher-next-link ()
 ;;
 
 (defun elpher-next-link ()


@@ -569,18 +785,6 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
   (interactive)
   (backward-button 1))
 
   (interactive)
   (backward-button 1))
 

-(defun elpher-click-link (button)
-  "Function called when the gopher link BUTTON is activated (via mouse or keypress)."
-  (let ((node (button-get button 'elpher-node)))
-    (elpher-visit-node node)))
-
-(defun elpher-click-url (button)
-  "Function called when the url link BUTTON is activated (via mouse or keypress)."
-  (let ((url (button-get button 'elpher-url)))
-    (if elpher-open-urls-with-eww
-        (browse-web url)
-      (browse-url url))))
-

 (defun elpher-follow-current-link ()
   "Open the link or url at point."
   (interactive)
 (defun elpher-follow-current-link ()
   "Open the link or url at point."
   (interactive)


@@ -589,38 +793,50 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
 (defun elpher-go ()
   "Go to a particular gopher site."
   (interactive)
 (defun elpher-go ()
   "Go to a particular gopher site."
   (interactive)

-  (let* (
-         (hostname (read-string "Gopher host: "))
-         (selector (read-string "Selector (default none): " nil nil ""))
-         (port (read-string "Port (default 70): " nil nil 70))
-         (address (list selector hostname port)))
-    (elpher-visit-node
-     (elpher-make-node elpher-current-node
-                        address
-                        #'elpher-get-index-node))))
+  (let ((node
+         (let ((host-or-url (read-string "Gopher host or URL: ")))
+           (if (string-match elpher-url-regex host-or-url)
+               (elpher-make-node-from-matched-url elpher-current-node
+                                                  host-or-url)
+             (let ((selector (read-string "Selector (default none): " nil nil ""))
+                   (port (string-to-number (read-string "Port (default 70): "
+                                                        nil nil 70))))
+               (elpher-make-node (concat "gopher://" host-or-url
+                                         ":" port
+                                         "/1" selector)
+                                 elpher-current-node
+                                 (elpher-make-address ?1 selector host-or-url port)))))))
+    (switch-to-buffer "*elpher*")
+    (elpher-visit-node node)))

 
 (defun  elpher-redraw ()
   "Redraw current page."
   (interactive)
 
 (defun  elpher-redraw ()
   "Redraw current page."
   (interactive)

-  (elpher-visit-node elpher-current-node))
+  (if elpher-current-node
+      (elpher-visit-node elpher-current-node)
+    (message "No current site.")))

 
 (defun  elpher-reload ()
   "Reload current page."
   (interactive)
 
 (defun  elpher-reload ()
   "Reload current page."
   (interactive)

-  (elpher-reload-current-node))
+  (if elpher-current-node
+      (elpher-reload-current-node)
+    (message "No current site.")))

 
 (defun elpher-view-raw ()
   "View current page as plain text."
   (interactive)
 
 (defun elpher-view-raw ()
   "View current page as plain text."
   (interactive)

-  (elpher-visit-node elpher-current-node
-                      #'elpher-get-node-raw))
+  (if elpher-current-node
+      (elpher-visit-node elpher-current-node
+                         #'elpher-get-node-raw)
+    (message "No current site.")))

 
 (defun elpher-back ()
   "Go to previous site."
   (interactive)
   (if (elpher-node-parent elpher-current-node)
       (elpher-visit-parent-node)
 
 (defun elpher-back ()
   "Go to previous site."
   (interactive)
   (if (elpher-node-parent elpher-current-node)
       (elpher-visit-parent-node)

-    (message "No previous site.")))
+    (error "No previous site")))

 
 (defun elpher-download ()
   "Download the link at point."
 
 (defun elpher-download ()
   "Download the link at point."


@@ -629,10 +845,108 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
     (if button
         (let ((node (button-get button 'elpher-node)))
           (if node
     (if button
         (let ((node (button-get button 'elpher-node)))
           (if node

-              (elpher-visit-node (button-get button 'elpher-node
-                                  #'elpher-get-node-download))
-            (message "Can only download gopher links, not general URLs.")))
-      (message "No link selected."))))
+              (elpher-visit-node (button-get button 'elpher-node)
+                                 #'elpher-get-node-download)
+            (error "Can only download gopher links, not general URLs")))
+      (error "No link selected"))))
+
+(defun elpher-build-link-map ()
+  "Build alist mapping link names to destination nodes in current buffer."
+  (let ((link-map nil)
+        (b (next-button (point-min) t)))
+    (while b
+      (add-to-list 'link-map (cons (button-label b) b))
+      (setq b (next-button (button-start b))))
+    link-map))
+
+(defun elpher-menu ()
+  "Select a directory entry by name.  Similar to the info browser (m)enu command."
+  (interactive)
+  (let* ((link-map (elpher-build-link-map)))
+    (if link-map
+        (let ((key (let ((completion-ignore-case t))
+                     (completing-read "Directory entry/link (tab to autocomplete): "
+                                      link-map nil t))))
+          (if (and key (> (length key) 0))
+              (let ((b (cdr (assoc key link-map))))
+                (goto-char (button-start b))
+                (button-activate b)))))))
+
+(defun elpher-root-dir ()
+  "Visit root of current server."
+  (interactive)
+  (let ((address (elpher-node-address elpher-current-node)))
+    (if address
+        (let ((host (elpher-address-host address))
+              (selector (elpher-address-selector address))
+              (port (elpher-address-port address)))
+          (if (> (length selector) 0)
+              (let ((root-address (elpher-make-address ?1 "" host port)))
+                (elpher-visit-node
+                 (elpher-make-node (concat "gopher://" host
+                                           ":" (number-to-string port)
+                                           "/1/")
+                                   elpher-current-node
+                                   root-address)))
+            (error "Already at root directory of current server")))
+      (error "Command invalid for Elpher start page"))))
+
+(defun elpher-info-node (node)
+  "Display information on NODE."
+  (let ((display-string (elpher-node-display-string node))
+        (address (elpher-node-address node)))
+    (if address
+        (message "`%s' on %s port %s"
+                (elpher-address-selector address)
+                (elpher-address-host address)
+                (elpher-address-port address))
+      (message "%s" display-string))))
+
+(defun elpher-info-link ()
+  "Display information on node corresponding to link at point."
+  (interactive)
+  (let ((button (button-at (point))))
+    (if button
+        (elpher-info-node (button-get button 'elpher-node))
+      (error "No item selected"))))
+  
+(defun elpher-info-current ()
+  "Display information on current node."
+  (interactive)
+  (elpher-info-node elpher-current-node))
+
+(defun elpher-get-address-url (address)
+  "Get URL representation of ADDRESS."
+  (concat "gopher://"
+          (elpher-address-host address)
+          (let ((port (elpher-address-port address)))
+            (if (equal port 70)
+                ""
+              (format ":%d" port)))
+          "/" (string (elpher-address-type address))
+          (elpher-address-selector address)))
+
+(defun elpher-copy-node-url (node)
+  "Copy URL representation of address of NODE to `kill-ring'."
+  (let ((address (elpher-node-address node)))
+    (if address
+        (let ((url (elpher-get-address-url address)))
+          (message url)
+          (kill-new url))
+      (error (format "Cannot represent %s as URL" (elpher-node-display-string node))))))
+
+(defun elpher-copy-link-url ()
+  "Copy URL of item at point to `kill-ring'."
+  (interactive)
+  (let ((button (button-at (point))))
+    (if button
+        (elpher-copy-node-url (button-get button 'elpher-node))
+      (error "No item selected"))))
+
+(defun elpher-copy-current-url ()
+  "Copy URL of current node to `kill-ring'."
+  (interactive)
+  (elpher-copy-node-url elpher-current-node))

 
 ;;; Mode and keymap
 ;;
 
 ;;; Mode and keymap
 ;;


@@ -642,28 +956,47 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
     (define-key map (kbd "TAB") 'elpher-next-link)
     (define-key map (kbd "<backtab>") 'elpher-prev-link)
     (define-key map (kbd "u") 'elpher-back)
     (define-key map (kbd "TAB") 'elpher-next-link)
     (define-key map (kbd "<backtab>") 'elpher-prev-link)
     (define-key map (kbd "u") 'elpher-back)

+    (define-key map (kbd "O") 'elpher-root-dir)

     (define-key map (kbd "g") 'elpher-go)
     (define-key map (kbd "r") 'elpher-redraw)
     (define-key map (kbd "R") 'elpher-reload)
     (define-key map (kbd "w") 'elpher-view-raw)
     (define-key map (kbd "d") 'elpher-download)
     (define-key map (kbd "g") 'elpher-go)
     (define-key map (kbd "r") 'elpher-redraw)
     (define-key map (kbd "R") 'elpher-reload)
     (define-key map (kbd "w") 'elpher-view-raw)
     (define-key map (kbd "d") 'elpher-download)

+    (define-key map (kbd "m") 'elpher-menu)
+    (define-key map (kbd "i") 'elpher-info-link)
+    (define-key map (kbd "I") 'elpher-info-current)
+    (define-key map (kbd "c") 'elpher-copy-link-url)
+    (define-key map (kbd "C") 'elpher-copy-current-url)

     (when (fboundp 'evil-define-key)
     (when (fboundp 'evil-define-key)

-      (evil-define-key 'normal map
+      (evil-define-key 'motion map

         (kbd "TAB") 'elpher-next-link
         (kbd "C-]") 'elpher-follow-current-link
         (kbd "C-t") 'elpher-back
         (kbd "u") 'elpher-back
         (kbd "TAB") 'elpher-next-link
         (kbd "C-]") 'elpher-follow-current-link
         (kbd "C-t") 'elpher-back
         (kbd "u") 'elpher-back

+        (kbd "O") 'elpher-root-dir

         (kbd "g") 'elpher-go
         (kbd "r") 'elpher-redraw
         (kbd "R") 'elpher-reload
         (kbd "w") 'elpher-view-raw
         (kbd "g") 'elpher-go
         (kbd "r") 'elpher-redraw
         (kbd "R") 'elpher-reload
         (kbd "w") 'elpher-view-raw

-        (kbd "d") 'elpher-download))
+        (kbd "d") 'elpher-download
+        (kbd "m") 'elpher-menu
+        (kbd "i") 'elpher-info-link
+        (kbd "I") 'elpher-info-current
+        (kbd "c") 'elpher-copy-link-url
+        (kbd "C") 'elpher-copy-current-url
+        (kbd "a") 'elpher-bookmark-link
+        (kbd "A") 'elpher-bookmark-current
+        (kbd "x") 'elpher-unbookmark-link
+        (kbd "X") 'elpher-unbookmark-current
+        (kbd "B") 'elpher-display-bookmarks))

     map)
   "Keymap for gopher client.")
 
 (define-derived-mode elpher-mode special-mode "elpher"
   "Major mode for elpher, an elisp gopher client.")
 
     map)
   "Keymap for gopher client.")
 
 (define-derived-mode elpher-mode special-mode "elpher"
   "Major mode for elpher, an elisp gopher client.")
 

+(when (fboundp 'evil-set-initial-state)
+  (evil-set-initial-state 'elpher-mode 'motion))

 
 ;;; Main start procedure
 ;;
 
 ;;; Main start procedure
 ;;


@@ -672,9 +1005,13 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
 (defun elpher ()
   "Start elpher with default landing page."
   (interactive)
 (defun elpher ()
   "Start elpher with default landing page."
   (interactive)

-  (setq elpher-current-node nil)
-  (let ((start-node (elpher-make-node nil nil #'elpher-get-index-node)))
-    (elpher-visit-node start-node))
+  (if (get-buffer "*elpher*")
+      (switch-to-buffer "*elpher*")
+    (switch-to-buffer "*elpher*")
+    (setq elpher-current-node nil)
+    (let ((start-node (elpher-make-node "Elpher Start Page"
+                                        nil elpher-start-address)))
+      (elpher-visit-node start-node)))

   "Started Elpher.") ; Otherwise (elpher) evaluates to start page string.
 
 ;;; elpher.el ends here
   "Started Elpher.") ; Otherwise (elpher) evaluates to start page string.
 
 ;;; elpher.el ends here