;;; 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.
+
+;; The caching mechanism works by maintaining a hierarchy of visited
+;; pages rather than a linear history, meaning that it is quick and
+;; easy to navigate this history.
+
+;; 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:
"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 - m: select a directory entry by name (autocompletes)\tfake\tfake\t1"
"i - u: return to parent directory entry\tfake\tfake\t1"
"i - g: go to a particular page\tfake\tfake\t1"
"i - r: redraw current page (using cached contents if available)\tfake\tfake\t1"
"\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)
+ (?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.")
+
;;; 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 org-drawer))
+ "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 org-tag))
+ "Face used for text type directory records.")
-(defface elpher-info '()
- "Face used for info records.")
+(defface elpher-info
+ '((t :inherit org-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 org-level-4))
+ "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 org-level-5))
+ "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 org-level-6))
+ "Face used for url type directory records.")
(defface elpher-binary
- '((t :foreground "magenta"))
- "Face used for binary records.")
+ '((t :inherit org-level-7))
+ "Face used for binary type directory records.")
(defface elpher-unknown
- '((t :foreground "red"))
- "Face used for unknown record types.")
+ '((t :inherit org-warning))
+ "Face used for directory records with unknown/unsupported types.")
(defface elpher-margin-key
- '((((background dark)) :foreground "white"))
- "Face used for margin key.")
+ '((t :inherit org-tag))
+ "Face used for directory margin key.")
(defface elpher-margin-brackets
- '((t :foreground "blue"))
- "Face used for brackets around margin key.")
+ '((t :inherit org-special-keyword))
+ "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-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))
+
+
;;; Model
;;
(defun elpher-insert-index (string)
"Insert the index corresponding to STRING into the current buffer."
- (dolist (line (split-string string "\r\n"))
+ ;; Should be able to split directly on CRLF, but some non-conformant
+ ;; LF-only servers sadly exist, hence the following.
+ (dolist (line (split-string (replace-regexp-in-string "\r" "" string) "\n"))
(unless (= (length line) 0)
(elpher-insert-index-record line))))
(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))
getter)
'action #'elpher-click-link
'follow-link t
- 'help-echo (format "mouse-1, RET: open %s on %s port %s"
+ 'help-echo (format "mouse-1, RET: open '%s' on %s port %s"
selector host port)))
(pcase type
- (?i (elpher-insert-margin) ; Information
+ (?i (elpher-insert-margin) ;; Information
(insert (propertize display-string
'face 'elpher-info)))
- (?h (elpher-insert-margin "W") ; Web link
+ (?h (elpher-insert-margin "W") ;; Web link
(let ((url (elt (split-string selector "URL:") 1)))
(insert-text-button display-string
'face 'elpher-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.
+ (?.) ;; 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)))))
(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"
getter)
'action #'elpher-click-link
'follow-link t
- 'help-echo (format "mouse-1, RET: open %s on %s port %s"
+ 'help-echo (format "mouse-1, RET: open '%s' on %s port %s"
selector host port)))
(make-text-button (match-beginning 0)
(match-end 0)
(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)))))))))
+ (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))
+ (setq cursor-type nil)
+ (elpher-restore-pos)
+ (if elpher-cache-images
+ (elpher-set-node-content elpher-current-node
+ image)))))))
+ (elpher-get-node-download)))))
;; Search retrieval
(let ((node (button-get button 'elpher-node)))
(if node
(elpher-visit-node (button-get button 'elpher-node)
- #'elpher-get-node-download)
+ #'elpher-get-node-download)
(message "Can only download gopher links, not general URLs.")))
(message "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)))))))
+
;;; Mode and keymap
;;
(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)
(when (fboundp 'evil-define-key)
(evil-define-key 'normal map
(kbd "TAB") 'elpher-next-link
(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))
map)
"Keymap for gopher client.")
"Start elpher with default landing page."
(interactive)
(setq elpher-current-node nil)
- (let ((start-node (elpher-make-node nil nil #'elpher-get-index-node)))
+ (let ((start-node (elpher-make-node nil
+ elpher-start-address
+ #'elpher-get-index-node)))
(elpher-visit-node start-node))
"Started Elpher.") ; Otherwise (elpher) evaluates to start page string.
The Lambda Lab / projects / elpher.git / blobdiff