Fixed bug in non-gopher URL construction.
[elpher.git] / elpher.el
index 94ba3be..d1d795c 100644 (file)
--- a/elpher.el
+++ b/elpher.el
@@ -1,10 +1,10 @@
-;;; elpher.el --- Full-featured gopher client.
+;;; elpher.el --- A friendly gopher client.
 
 ;; Copyright (C) 2019 Tim Vaughan
 
 ;; Author: Tim Vaughan <tgvaughan@gmail.com>
 ;; Created: 11 April 2019
-;; Version: 1.1.0
+;; Version: 1.2.4
 ;; Keywords: comm gopher
 ;; Homepage: https://github.com/tgvaughan/elpher
 ;; Package-Requires: ((emacs "25"))
@@ -26,7 +26,7 @@
 
 ;;; Commentary:
 
-;; Elpher aims to provide a full-featured gopher client for GNU Emacs.
+;; Elpher aims to provide a practical gopher client for GNU Emacs.
 ;; It supports:
 
 ;; - intuitive keyboard and mouse-driven interface,
@@ -34,7 +34,8 @@
 ;; - 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.
+;; - clickable web and gopher links in plain text,
+;; - a simple bookmark management system.
 
 ;; Visited pages are stored as a hierarchy rather than a linear history,
 ;; meaning that navigation between these pages is quick and easy.
@@ -43,7 +44,7 @@
 ;; page containing information on key bindings and suggested starting
 ;; points for your gopher exploration.
 
-;; Faces, caching options and start page can be configured via
+;; Faces, caching and other options can be configured via
 ;; the Elpher customization group in Applications.
 
 ;;; Code:
 (provide 'elpher)
 (require 'seq)
 (require 'pp)
+(require 'shr)
 
 ;;; Global constants
 ;;
 
-(defconst elpher-version "1.1.0"
+(defconst elpher-version "1.2.4"
   "Current version of elpher.")
 
 (defconst elpher-margin-width 6
          "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 - a/A: bookmark the item under cursor or current page\tfake\tfake\t1"
+         "i - x/X: remove bookmark for item under cursor or current page\tfake\tfake\t1"
+         "i - B: visit the bookmarks 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 - w: display the raw server response for the current page\tfake\tfake\t1"
          "i\tfake\tfake\t1"
-         "iPlaces to start exploring Gopherspace:\tfake\tfake\t1"
+         "iWhere to start exploring Gopherspace:\tfake\tfake\t1"
          "i\tfake\tfake\t1"
-         "1Floodgap Systems Gopher Server\t\tgopher.floodgap.com\t70"
+         "1Floodgap Systems Gopher Server\t/\tgopher.floodgap.com\t70"
          "i\tfake\tfake\t1"
          "iAlternatively, select the following item and enter some\tfake\tfake\t1"
          "isearch terms:\tfake\tfake\t1"
   "Source for elpher start page.")
 
 (defconst elpher-type-map
-  '((?0 elpher-get-text-node "T" elpher-text)
+  '((?0 elpher-get-text-node "txt" 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)
+    (?4 elpher-get-node-download "bin" elpher-binary)
+    (?5 elpher-get-node-download "bin" 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)
+    (?8 elpher-get-telnet-node "tel" elpher-telnet)
+    (?9 elpher-get-node-download "bin" elpher-binary)
+    (?g elpher-get-image-node "img" elpher-image)
+    (?p elpher-get-image-node "img" elpher-image)
+    (?I elpher-get-image-node "img" elpher-image)
+    (?d elpher-get-node-download "doc" elpher-binary)
+    (?h elpher-get-url-node "web" elpher-url)
     (bookmarks elpher-get-bookmarks-node "#" elpher-index)
     (start elpher-get-start-node "#" elpher-index))
   "Association list from types to getters, margin codes and index faces.")
@@ -182,12 +188,6 @@ Otherwise, use the system browser via the BROWSE-URL function."
   "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))
@@ -219,56 +219,78 @@ special address types, such as 'start for the start page."
   "Retrieve port from ADDRESS."
   (elt address 3))
 
+(defun elpher-address-special-p (address)
+  "Return non-nil if ADDRESS is special (e.g. start page, bookmarks page)."
+  (not (elpher-address-host address)))
+
 ;; Node
 
-(defun elpher-make-node (display-string parent address &optional content pos)
+(defun elpher-make-node (display-string address &optional parent)
   "Create a node in the gopher page hierarchy.
 
 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.
+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."
-  (list display-string parent address content pos))
+The optional PARENT specifies the parent node in the hierarchy.
+This is set every time the node is visited, so while it forms
+an important part of the node data there is no need to set it
+initially."
+  (list display-string address parent))
 
 (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."
-  (elt node 1))
-
 (defun elpher-node-address (node)
   "Retrieve the address of NODE."
+  (elt node 1))
+
+(defun elpher-node-parent (node)
+  "Retrieve the parent node of NODE."
   (elt node 2))
 
-(defun elpher-node-content (node)
-  "Retrieve the cached content of NODE, or nil if none exists."
-  (elt node 3))
+(defun elpher-set-node-parent (node parent)
+  "Set the parent node of NODE to be PARENT."
+  (setcar (cdr (cdr node)) parent))
+
+;; Cache
 
-(defun elpher-node-pos (node)
-  "Retrieve the cached cursor position for NODE, or nil if none exists."
-  (elt node 4))
+(defvar elpher-content-cache (make-hash-table :test 'equal))
+(defvar elpher-pos-cache (make-hash-table :test 'equal))
 
-(defun elpher-set-node-content (node content)
-  "Set the content cache of NODE to CONTENT."
-  (setcar (nthcdr 3 node) content))
+(defun elpher-get-cached-content (address)
+  "Retrieve the cached content for ADDRESS, or nil if none exists."
+  (gethash address elpher-content-cache))
 
-(defun elpher-set-node-pos (node pos)
-  "Set the cursor position cache of NODE to POS."
-  (setcar (nthcdr 4 node) pos))
+(defun elpher-cache-content (address content)
+  "Set the content cache for ADDRESS to CONTENT."
+  (puthash address content elpher-content-cache))
+
+(defun elpher-get-cached-pos (address)
+  "Retrieve the cached cursor position for ADDRESS, or nil if none exists."
+  (gethash address elpher-pos-cache))
+
+(defun elpher-cache-pos (address pos)
+  "Set the cursor position cache for ADDRESS to POS."
+  (puthash address pos elpher-pos-cache))
 
 ;; Node graph traversal
 
 (defvar elpher-current-node nil)
 
-(defun elpher-visit-node (node &optional getter)
-  "Visit NODE using its own getter or GETTER, if non-nil."
+(defun elpher-visit-node (node &optional getter preserve-parent)
+  "Visit NODE using its own getter or GETTER, if non-nil.
+Additionally, set the parent of NODE to `elpher-current-node',
+unless PRESERVE-PARENT is non-nil."
   (elpher-save-pos)
   (elpher-process-cleanup)
+  (unless preserve-parent
+    (if (and (elpher-node-parent elpher-current-node)
+             (equal (elpher-node-address elpher-current-node)
+                    (elpher-node-address node)))
+        (elpher-set-node-parent node (elpher-node-parent elpher-current-node))
+      (elpher-set-node-parent node elpher-current-node)))
   (setq elpher-current-node node)
   (if getter
       (funcall getter)
@@ -280,21 +302,21 @@ content and cursor position fields of the node."
   "Visit the parent of the current node."
   (let ((parent-node (elpher-node-parent elpher-current-node)))
     (when parent-node
-      (elpher-visit-node parent-node))))
+      (elpher-visit-node parent-node nil t))))
       
 (defun elpher-reload-current-node ()
   "Reload the current node, discarding any existing cached content."
-  (elpher-set-node-content elpher-current-node nil)
+  (elpher-cache-content (elpher-node-address elpher-current-node) nil)
   (elpher-visit-node elpher-current-node))
 
 (defun elpher-save-pos ()
   "Save the current position of point to the current node."
   (when elpher-current-node
-    (elpher-set-node-pos elpher-current-node (point))))
+    (elpher-cache-pos (elpher-node-address elpher-current-node) (point))))
 
 (defun elpher-restore-pos ()
   "Restore the position of point to that cached in the current node."
-  (let ((pos (elpher-node-pos elpher-current-node)))
+  (let ((pos (elpher-get-cached-pos (elpher-node-address elpher-current-node))))
     (if pos
         (goto-char pos)
       (goto-char (point-min)))))
@@ -374,9 +396,9 @@ and PORT."
   (let ((address (elpher-make-address type selector host port))
         (type-map-entry (alist-get type elpher-type-map)))
     (if 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)))
+        (let* ((margin-code (elt type-map-entry 1))
+               (face (elt type-map-entry 2))
+               (node (elpher-make-node display-string address)))
           (elpher-insert-margin margin-code)
           (insert-text-button display-string
                               'face face
@@ -395,7 +417,7 @@ and PORT."
         (other ;; Unknown
          (elpher-insert-margin (concat (char-to-string type) "?"))
          (insert (propertize display-string
-                             'face 'elpher-unknown-face)))))
+                             'face 'elpher-unknown)))))
     (insert "\n")))
 
 (defun elpher-click-link (button)
@@ -418,37 +440,46 @@ and PORT."
   "Retrieve selector specified by ADDRESS, then execute AFTER.
 The result is stored as a string in the variable ‘elpher-selector-string’."
   (setq elpher-selector-string "")
-  (make-network-process
-   :name "elpher-process"
-   :host (elpher-address-host address)
-   :service (elpher-address-port address)
-   :filter (lambda (proc string)
-             (setq elpher-selector-string (concat elpher-selector-string string)))
-   :sentinel after)
-  (process-send-string "elpher-process"
-                       (concat (elpher-address-selector address) "\n")))
+  (condition-case nil
+      (progn
+        (make-network-process :name "elpher-process"
+                              :host (elpher-address-host address)
+                              :service (elpher-address-port address)
+                              :filter (lambda (proc string)
+                                        (setq elpher-selector-string
+                                              (concat elpher-selector-string string)))
+                              :sentinel after)
+        (process-send-string "elpher-process"
+                             (concat (elpher-address-selector address) "\n")))
+    (error
+     (elpher-with-clean-buffer
+      (insert (propertize "\n---- ERROR -----\n\n" 'face 'error)
+              "Failed to connect to " (elpher-get-address-url address) ".\n"
+              (propertize "\n----------------\n\n" 'face 'error)
+              "Press 'u' to return to the previous page.")))))
 
 ;; Index retrieval
 
 (defun elpher-get-index-node ()
   "Getter which retrieves the current node contents as an index."
-  (let ((content (elpher-node-content elpher-current-node))
-        (address (elpher-node-address elpher-current-node)))
+  (let* ((address (elpher-node-address elpher-current-node))
+         (content (elpher-get-cached-content address)))
     (if content
         (progn
           (elpher-with-clean-buffer
            (insert content)
            (elpher-restore-pos)))
       (elpher-with-clean-buffer
-       (insert "LOADING DIRECTORY..."))
+       (insert "LOADING DIRECTORY... (use 'u' to cancel)"))
       (elpher-get-selector address
                            (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-cache-content
+                                 (elpher-node-address elpher-current-node)
+                                 (buffer-string)))))))))
 
 ;; Text retrieval
 
@@ -456,11 +487,9 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
   "\\([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.")
 
-(defun elpher-make-node-from-matched-url (parent &optional string)
+(defun elpher-make-node-from-matched-url (&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))
@@ -478,14 +507,14 @@ calls, as is necessary if the match is performed by `string-match'."
                              (substring type-and-selector 2)
                            ""))
                (address (elpher-make-address type selector host port)))
-          (elpher-make-node url elpher-current-node address))
+          (elpher-make-node url 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)))))
+        (elpher-make-node url address)))))
 
 
 (defun elpher-buttonify-urls (string)
@@ -494,7 +523,7 @@ calls, as is necessary if the match is performed by `string-match'."
     (insert string)
     (goto-char (point-min))
     (while (re-search-forward elpher-url-regex nil t)
-        (let ((node (elpher-make-node-from-matched-url elpher-current-node)))
+        (let ((node (elpher-make-node-from-matched-url)))
           (make-text-button (match-beginning 0)
                             (match-end 0)
                             'elpher-node  node
@@ -505,8 +534,8 @@ calls, as is necessary if the match is performed by `string-match'."
 
 (defun elpher-get-text-node ()
   "Getter which retrieves the current node contents as a text document."
-  (let ((content (elpher-node-content elpher-current-node))
-        (address (elpher-node-address elpher-current-node)))
+  (let* ((address (elpher-node-address elpher-current-node))
+         (content (elpher-get-cached-content address)))
     (if content
         (progn
           (elpher-with-clean-buffer
@@ -514,7 +543,7 @@ calls, as is necessary if the match is performed by `string-match'."
            (elpher-restore-pos)))
       (progn
         (elpher-with-clean-buffer
-         (insert "LOADING TEXT..."))
+         (insert "LOADING TEXT... (use 'u' to cancel)"))
         (elpher-get-selector address
                               (lambda (proc event)
                                 (unless (string-prefix-p "deleted" event)
@@ -523,15 +552,16 @@ calls, as is necessary if the match is performed by `string-match'."
                                             (elpher-preprocess-text-response
                                              elpher-selector-string)))
                                    (elpher-restore-pos)
-                                   (elpher-set-node-content elpher-current-node
-                                                            (buffer-string))))))))))
+                                   (elpher-cache-content
+                                    (elpher-node-address elpher-current-node)
+                                    (buffer-string))))))))))
 
 ;; Image retrieval
 
 (defun elpher-get-image-node ()
   "Getter which retrieves the current node contents as an image to view."
-  (let ((content (elpher-node-content elpher-current-node))
-        (address (elpher-node-address elpher-current-node)))
+  (let* ((address (elpher-node-address elpher-current-node))
+         (content (elpher-get-cached-content address)))
     (if content
         (progn
           (elpher-with-clean-buffer
@@ -540,7 +570,7 @@ calls, as is necessary if the match is performed by `string-match'."
       (if (display-images-p)
           (progn
             (elpher-with-clean-buffer
-             (insert "LOADING IMAGE..."))
+             (insert "LOADING IMAGE... (use 'u' to cancel)"))
             (elpher-get-selector address
                                  (lambda (proc event)
                                    (unless (string-prefix-p "deleted" event)
@@ -553,17 +583,18 @@ calls, as is necessary if the match is performed by `string-match'."
                                         (insert-image image)
                                         (elpher-restore-pos))
                                        (if elpher-cache-images
-                                           (elpher-set-node-content elpher-current-node
-                                                                    image)))))))
+                                           (elpher-cache-content
+                                            (elpher-node-address elpher-current-node)
+                                            image)))))))
         (elpher-get-node-download)))))
 
 ;; Search retrieval
 
 (defun elpher-get-search-node ()
   "Getter which submits a search query to the address of the current node."
-  (let ((content (elpher-node-content elpher-current-node))
-        (address (elpher-node-address elpher-current-node))
-        (aborted t))
+  (let* ((address (elpher-node-address elpher-current-node))
+         (content (elpher-get-cached-content address))
+         (aborted t))
     (if content
         (progn
           (elpher-with-clean-buffer
@@ -579,15 +610,16 @@ calls, as is necessary if the match is performed by `string-match'."
                                                       (elpher-address-port address))))
             (setq aborted nil)
             (elpher-with-clean-buffer
-             (insert "LOADING RESULTS..."))
+             (insert "LOADING RESULTS... (use 'u' to cancel)"))
             (elpher-get-selector search-address
                                   (lambda (proc event)
                                     (unless (string-prefix-p "deleted" event)
                                       (elpher-with-clean-buffer
                                        (elpher-insert-index elpher-selector-string))
                                       (goto-char (point-min))
-                                      (elpher-set-node-content elpher-current-node
-                                                                (buffer-string))))))
+                                      (elpher-cache-content
+                                       (elpher-node-address elpher-current-node)
+                                       (buffer-string))))))
         (if aborted
             (elpher-visit-parent-node))))))
 
@@ -595,10 +627,9 @@ calls, as is necessary if the match is performed by `string-match'."
 
 (defun elpher-get-node-raw ()
   "Getter which retrieves the raw server response for the current node."
-  (let* ((content (elpher-node-content elpher-current-node))
-         (address (elpher-node-address elpher-current-node)))
+  (let ((address (elpher-node-address elpher-current-node)))
     (elpher-with-clean-buffer
-     (insert "LOADING RAW SERVER RESPONSE..."))
+     (insert "LOADING RAW SERVER RESPONSE... (use 'u' to cancel)"))
     (if address
         (elpher-get-selector address
                               (lambda (proc event)
@@ -639,15 +670,42 @@ calls, as is necessary if the match is performed by `string-match'."
 
 ;; URL retrieval
 
+(defun elpher-insert-rendered-html (string)
+  "Use shr to insert rendered view of html STRING into current buffer."
+  (let ((dom (with-temp-buffer
+               (insert string)
+               (libxml-parse-html-region (point-min) (point-max)))))
+    (shr-insert-document dom)))
+
 (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)))))
+      (if url
+          (progn
+            (elpher-visit-parent-node) ; Do first in case of non-local exits.
+            (message "Opening URL...")
+            (if elpher-open-urls-with-eww
+                (browse-web url)
+              (browse-url url)))
+        (let ((content (elpher-get-cached-content address)))
+          (if content
+              (progn
+                (elpher-with-clean-buffer
+                 (insert content)
+                 (elpher-restore-pos)))
+            (elpher-with-clean-buffer
+             (insert "LOADING HTML... (use 'u' to cancel)"))
+            (elpher-get-selector address
+                                 (lambda (proc event)
+                                   (unless (string-prefix-p "deleted" event)
+                                     (elpher-with-clean-buffer
+                                      (elpher-insert-rendered-html elpher-selector-string)
+                                      (goto-char (point-min))
+                                      (elpher-cache-content
+                                       (elpher-node-address elpher-current-node)
+                                       (buffer-string))))))))))))
 
 ;; Telnet node connection
 
@@ -659,13 +717,38 @@ calls, as is necessary if the match is performed by `string-match'."
     (elpher-visit-parent-node)
     (telnet host port)))
 
-;; Start node retrieval
+;; Start page node retrieval
 
 (defun elpher-get-start-node ()
   "Getter which displays the start page."
   (elpher-with-clean-buffer
    (elpher-insert-index elpher-start-index)
    (elpher-restore-pos)))
+
+;; Bookmarks page node retrieval
+
+(defun elpher-get-bookmarks-node ()
+  "Getter to load and display the current bookmark list."
+  (elpher-with-clean-buffer
+   (insert "---- 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-----------------------\n\n"
+           "- u: return to previous page\n"
+           "- x: delete selected bookmark\n"
+           "- a: rename selected bookmark\n\n"
+           "Bookmarks are stored in the file "
+           (locate-user-emacs-file "elpher-bookmarks"))
+   (elpher-restore-pos)))
   
 
 ;;; Bookmarks
@@ -681,6 +764,10 @@ bookmark list, while ADDRESS is the address of the entry."
   "Get the display string of BOOKMARK."
   (elt bookmark 0))
 
+(defun elpher-set-bookmark-display-string (bookmark display-string)
+  "Set the display string of BOOKMARK to DISPLAY-STRING."
+  (setcar bookmark display-string))
+
 (defun elpher-bookmark-address (bookmark)
   "Get the address for BOOKMARK."
   (elt bookmark 1))
@@ -690,6 +777,10 @@ bookmark list, while ADDRESS is the address of the entry."
 Beware that this completely replaces the existing contents of the file."
   (with-temp-file (locate-user-emacs-file "elpher-bookmarks")
     (erase-buffer)
+    (insert "; Elpher gopher bookmarks file\n\n"
+            "; Bookmarks are stored as a list of (label (type selector host port))\n"
+            "; s-expressions, where type is stored as a character (i.e. 49 = ?1).\n"
+            "; Feel free to edit by hand, but ensure this structure remains intact.\n\n")
     (pp bookmarks (current-buffer))))
 
 (defun elpher-load-bookmarks ()
@@ -700,71 +791,24 @@ Beware that this completely replaces the existing contents of the file."
       (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)
+(defun elpher-add-address-bookmark (address display-string)
+  "Save a bookmark for ADDRESS with label DISPLAY-STRING.
+If ADDRESS is already bookmarked, update the label only."
+  (let ((bookmarks (elpher-load-bookmarks)))
+    (let ((existing-bookmark (rassoc (list address) bookmarks)))
+      (if existing-bookmark
+          (elpher-set-bookmark-display-string existing-bookmark display-string)
+        (add-to-list 'bookmarks (elpher-make-bookmark display-string address))))
     (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))))
+(defun elpher-remove-address-bookmark (address)
+  "Remove any bookmark to ADDRESS."
     (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"))))
+     (seq-filter (lambda (bookmark)
+                   (not (equal (elpher-bookmark-address bookmark) address)))
+                 (elpher-load-bookmarks))))
 
-(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"))))
-
-;;; Interactive navigation procedures
+;;; Interactive procedures
 ;;
 
 (defun elpher-next-link ()
@@ -783,19 +827,19 @@ Beware that this completely replaces the existing contents of the file."
   (push-button))
 
 (defun elpher-go ()
-  "Go to a particular gopher site."
+  "Go to a particular gopher site read from the minibuffer.
+The site may be specified via a URL or explicitly in terms of
+host, selector and port."
   (interactive)
   (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)
+               (elpher-make-node-from-matched-url host-or-url)
              (let ((selector (read-string "Selector (default none): " nil nil ""))
                    (port-string (read-string "Port (default 70): " nil nil "70")))
                (elpher-make-node (concat "gopher://" host-or-url
                                          ":" port-string
                                          "/1" selector)
-                                 elpher-current-node
                                  (elpher-make-address ?1 selector host-or-url
                                                       (string-to-number port-string))))))))
     (switch-to-buffer "*elpher*")
@@ -816,11 +860,13 @@ Beware that this completely replaces the existing contents of the file."
     (message "No current site.")))
 
 (defun elpher-view-raw ()
-  "View current page as plain text."
+  "View raw server response for current page."
   (interactive)
   (if elpher-current-node
-      (elpher-visit-node elpher-current-node
-                         #'elpher-get-node-raw)
+      (if (elpher-address-special-p (elpher-node-address elpher-current-node))
+          (error "This page was not generated by a server")
+        (elpher-visit-node elpher-current-node
+                           #'elpher-get-node-raw))
     (message "No current site.")))
 
 (defun elpher-back ()
@@ -836,10 +882,10 @@ Beware that this completely replaces the existing contents of the file."
   (let ((button (button-at (point))))
     (if button
         (let ((node (button-get button 'elpher-node)))
-          (if node
-              (elpher-visit-node (button-get button 'elpher-node)
-                                 #'elpher-get-node-download)
-            (error "Can only download gopher links, not general URLs")))
+          (if (elpher-address-special-p (elpher-node-address node))
+              (error "Cannot download this link")
+            (elpher-visit-node (button-get button 'elpher-node)
+                               #'elpher-get-node-download)))
       (error "No link selected"))))
 
 (defun elpher-build-link-map ()
@@ -857,7 +903,7 @@ Beware that this completely replaces the existing contents of the file."
   (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): "
+                     (completing-read "Directory item/link: "
                                       link-map nil t))))
           (if (and key (> (length key) 0))
               (let ((b (cdr (assoc key link-map))))
@@ -879,11 +925,68 @@ Beware that this completely replaces the existing contents of the file."
                  (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 this page"))))
 
+(defun elpher-bookmarks-current-p ()
+  "Return non-nil if current node is a bookmarks page."
+  (eq (elpher-address-type (elpher-node-address elpher-current-node)) 'bookmarks))
+
+(defun elpher-reload-bookmarks ()
+  "Reload bookmarks if current node is a bookmarks page."
+  (if (elpher-bookmarks-current-p)
+      (elpher-reload-current-node)))
+
+(defun elpher-bookmark-current ()
+  "Bookmark the current node."
+  (interactive)
+  (unless (elpher-bookmarks-current-p)
+      (let ((address (elpher-node-address elpher-current-node))
+            (display-string (read-string "Bookmark display string: "
+                                         (elpher-node-display-string elpher-current-node))))
+        (elpher-add-address-bookmark address display-string)
+        (message "Bookmark added."))))
+
+(defun elpher-bookmark-link ()
+  "Bookmark the link at point."
+  (interactive)
+  (let ((button (button-at (point))))
+    (if button
+        (let* ((node (button-get button 'elpher-node))
+               (address (elpher-node-address node))
+               (display-string (read-string "Bookmark display string: "
+                                            (elpher-node-display-string node))))
+          (elpher-add-address-bookmark address display-string)
+          (elpher-reload-bookmarks)
+          (message "Bookmark added."))
+      (error "No link selected"))))
+
+(defun elpher-unbookmark-current ()
+  "Remove bookmark for the current node."
+  (interactive)
+  (unless (elpher-bookmarks-current-p)
+    (elpher-remove-address-bookmark (elpher-node-address elpher-current-node))
+    (message "Bookmark removed.")))
+
+(defun elpher-unbookmark-link ()
+  "Remove bookmark for the link at point."
+  (interactive)
+  (let ((button (button-at (point))))
+    (if button
+        (let ((node (button-get button 'elpher-node)))
+          (elpher-remove-address-bookmark (elpher-node-address node))
+          (elpher-reload-bookmarks)
+          (message "Bookmark removed."))
+      (error "No link selected"))))
+
+(defun elpher-bookmarks ()
+  "Visit bookmarks."
+  (interactive)
+  (switch-to-buffer "*elpher*")
+  (elpher-visit-node
+   (elpher-make-node "Bookmarks" (elpher-make-address 'bookmarks))))
+
 (defun elpher-info-node (node)
   "Display information on NODE."
   (let ((display-string (elpher-node-display-string node))
@@ -910,14 +1013,20 @@ Beware that this completely replaces the existing contents of the file."
 
 (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)))
+  (let ((type (elpher-address-type address))
+        (selector (elpher-address-selector address))
+        (host (elpher-address-host address))
+        (port (elpher-address-port address)))
+    (if (and (equal type ?h)
+             (string-prefix-p "URL:" selector))
+        (elt (split-string selector "URL:") 1)
+      (concat "gopher://"
+              host
+              (if (equal port 70)
+                  ""
+                (format ":%d" port))
+              "/" (string type)
+              selector))))
 
 (defun elpher-copy-node-url (node)
   "Copy URL representation of address of NODE to `kill-ring'."
@@ -960,6 +1069,11 @@ Beware that this completely replaces the existing contents of the file."
     (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)
+    (define-key map (kbd "a") 'elpher-bookmark-link)
+    (define-key map (kbd "A") 'elpher-bookmark-current)
+    (define-key map (kbd "x") 'elpher-unbookmark-link)
+    (define-key map (kbd "X") 'elpher-unbookmark-current)
+    (define-key map (kbd "B") 'elpher-bookmarks)
     (when (fboundp 'evil-define-key)
       (evil-define-key 'motion map
         (kbd "TAB") 'elpher-next-link
@@ -981,7 +1095,7 @@ Beware that this completely replaces the existing contents of the file."
         (kbd "A") 'elpher-bookmark-current
         (kbd "x") 'elpher-unbookmark-link
         (kbd "X") 'elpher-unbookmark-current
-        (kbd "B") 'elpher-display-bookmarks))
+        (kbd "B") 'elpher-bookmarks))
     map)
   "Keymap for gopher client.")
 
@@ -1002,7 +1116,8 @@ Beware that this completely replaces the existing contents of the file."
       (switch-to-buffer "*elpher*")
     (switch-to-buffer "*elpher*")
     (setq elpher-current-node nil)
-    (let ((start-node (elpher-make-node "Elpher Start Page" nil (elpher-make-address 'start))))
+    (let ((start-node (elpher-make-node "Elpher Start Page"
+                                        (elpher-make-address 'start))))
       (elpher-visit-node start-node)))
   "Started Elpher.") ; Otherwise (elpher) evaluates to start page string.