;; Author: Tim Vaughan <tgvaughan@gmail.com>
;; Created: 11 April 2019
-;; Version: 1.0.0
+;; Version: 1.2.0
;; Keywords: comm gopher
;; Homepage: https://github.com/tgvaughan/elpher
;; Package-Requires: ((emacs "25"))
;;; 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 interface,
+;; - 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)
+(require 'seq)
+(require 'pp)
;;; Global constants
;;
-(defconst elpher-version "1.0.0"
+(defconst elpher-version "1.2.0"
"Current version of elpher.")
(defconst elpher-margin-width 6
(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"
- "iBasic usage:\tfake\tfake\t1"
+ "iUsage:\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 - 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"
"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.")
+(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)
+ (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.")
+
;;; Customization group
;;
"A gopher client."
:group 'applications)
+;; Face customizations
+
(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
- '((((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
- '((((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
- '((((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
- '((((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
- '((t :foreground "magenta"))
- "Face used for binary records.")
+ '((t :inherit font-lock-doc-face))
+ "Face used for binary type directory records.")
(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
- '((((background dark)) :foreground "white"))
- "Face used for margin key.")
+ '((t :inherit bold))
+ "Face used for directory margin key.")
(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-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-use-header t
+ "If non-nil, display current node information in buffer header."
+ :type '(boolean))
+
;;; 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 &optional selector host port)
+ "Create an address of a gopher object with TYPE, SELECTOR, HOST and PORT.
+Although selector host and port are optional, they are only omitted for
+special address types, such as 'start for the start page."
+ (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."
- (car address))
+ (elt address 1))
(defun elpher-address-host (address)
"Retrieve host from ADDRESS."
- (cadr address))
+ (elt address 2))
(defun elpher-address-port (address)
"Retrieve port from ADDRESS."
- (caddr address))
+ (elt address 3))
;; Node
-(defun elpher-make-node (parent address getter &optional content pos)
+(defun elpher-make-node (display-string parent address)
"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."
+ (list display-string parent address))
-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))
+(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 0))
+ (elt node 1))
(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)
- "Retrieve the cached content of NODE, or nil if none exists."
- (elt node 3))
+;; 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)
+(defvar elpher-current-node nil)
(defun elpher-visit-node (node &optional getter)
"Visit NODE using its own getter or GETTER, if non-nil."
(setq elpher-current-node node)
(if getter
(funcall getter)
- (funcall (elpher-node-getter node))))
+ (let* ((address (elpher-node-address node))
+ (type (elpher-address-type address)))
+ (funcall (car (alist-get type elpher-type-map))))))
(defun elpher-visit-parent-node ()
"Visit the parent of the current node."
(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)))))
+
;;; 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."
- (list 'progn
- '(switch-to-buffer "*elpher*")
+ (list 'with-current-buffer "*elpher*"
'(elpher-mode)
(append (list 'let '((inhibit-read-only t))
- '(erase-buffer))
+ '(erase-buffer)
+ '(elpher-update-header))
args)))
+
;;; 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."
- (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)))
+ (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)))
+ (elpher-insert-index-record display-string type selector host port))))))
(defun elpher-insert-margin (&optional type-name)
"Insert index margin, optionally containing the TYPE-NAME, into the current buffer."
(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
- (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 (elt type-map-entry 2))
+ (node (elpher-make-node display-string elpher-current-node address)))
(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
- 'help-echo (format "mouse-1, RET: open %s on %s port %s"
- selector host port)))
+ 'help-echo (elpher-node-button-help node)))
(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")))
+(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)
;;
(defun elpher-get-selector (address after)
"Retrieve selector specified by ADDRESS, then execute AFTER.
-The result is stored as a string in the variable elpher-selector-string."
+The result is stored as a string in the variable ‘elpher-selector-string’."
(setq elpher-selector-string "")
(make-network-process
:name "elpher-process"
(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))
- (if address
- (progn
- (elpher-with-clean-buffer
- (insert "LOADING DIRECTORY..."))
- (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))))))
- (progn
- (elpher-with-clean-buffer
- (elpher-insert-index elpher-start-index))
- (elpher-restore-pos)
- (elpher-set-node-content elpher-current-node
- (buffer-string)))))))
+ (insert content)
+ (elpher-restore-pos)))
+ (elpher-with-clean-buffer
+ (insert "LOADING DIRECTORY..."))
+ (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-cache-content
+ (elpher-node-address elpher-current-node)
+ (buffer-string)))))))))
;; 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.")
+(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)
- (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)
- 'elpher-url url
- 'action #'elpher-click-url
+ 'elpher-node node
+ 'action #'elpher-click-link
'follow-link t
- 'help-echo (format "mouse-1, RET: open url %s" url)))))
+ 'help-echo (elpher-node-button-help node))))
(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))
- (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))
+ (insert content)
+ (elpher-restore-pos)))
(progn
(elpher-with-clean-buffer
(insert "LOADING TEXT..."))
(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-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
- (insert-image content))
- (setq cursor-type nil)
- (elpher-restore-pos))
- (progn
- (elpher-with-clean-buffer
- (insert "LOADING IMAGE..."))
- (elpher-get-selector address
- (lambda (proc event)
- (unless (string-prefix-p "deleted" event)
- (let ((image (create-image
- (encode-coding-string elpher-selector-string
- 'no-conversion)
- nil t)))
- (elpher-with-clean-buffer
- (insert-image image))
- (setq cursor-type nil)
- (elpher-restore-pos)
- (elpher-set-node-content elpher-current-node
- image)))))))))
+ (insert-image content)
+ (elpher-restore-pos)))
+ (if (display-images-p)
+ (progn
+ (elpher-with-clean-buffer
+ (insert "LOADING IMAGE..."))
+ (elpher-get-selector address
+ (lambda (proc event)
+ (unless (string-prefix-p "deleted" event)
+ (let ((image (create-image
+ (encode-coding-string
+ elpher-selector-string
+ 'no-conversion)
+ nil t)))
+ (elpher-with-clean-buffer
+ (insert-image image)
+ (elpher-restore-pos))
+ (if elpher-cache-images
+ (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
- (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))
- (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..."))
(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))))))
(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..."))
(if address
(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))
(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
-;;; Navigation procedures
+(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)))
+
+;; 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 which loads and displays 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")
+ (elpher-restore-pos)))
+
+
+;;; 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-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))
+
+(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-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-address-bookmark (address)
+ "Remove any bookmark to ADDRESS."
+ (elpher-save-bookmarks
+ (seq-filter (lambda (bookmark)
+ (not (equal (elpher-bookmark-address bookmark) address)))
+ (elpher-load-bookmarks))))
+
+;;; Interactive procedures
;;
(defun elpher-next-link ()
(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-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 (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*")
+ (elpher-visit-node node)))
(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)
- (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)
- (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)
- (message "No previous site.")))
+ (error "No previous site")))
(defun elpher-download ()
"Download the link at point."
(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-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-jump ()
+ "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))
+ (host (elpher-address-host address)))
+ (if host
+ (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 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)
+ (elpher-visit-node
+ (elpher-make-node "Bookmarks"
+ elpher-current-node
+ (elpher-make-address 'bookmarks))))
+
+(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
;;
(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 "m") 'elpher-jump)
+ (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)
+ (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 '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 "O") 'elpher-root-dir
(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-jump
+ (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-bookmarks))
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
;;
(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-make-address 'start))))
+ (elpher-visit-node start-node)))
"Started Elpher.") ; Otherwise (elpher) evaluates to start page string.
;;; elpher.el ends here