;; 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"))
;; - (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.
+;; 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
;;; Code:
(provide 'elpher)
+(require 'seq)
+(require 'pp)
;;; Global constants
;;
-(defconst elpher-version "1.0.0"
+(defconst elpher-version "1.1.0"
"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 - m: select a directory entry by name (autocompletes)\tfake\tfake\t1"
"i - u: return to parent directory entry\tfake\tfake\t1"
+ "i - O: visit the root directory of the current server\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"
"i - R: reload current page (regenerates cache)\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.")
;; 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
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))
;; 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."
(goto-char pos)
(goto-char (point-min)))))
+
;;; Buffer preparation
;;
(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))
args)))
+
;;; Index rendering
;;
(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-no-period (replace-regexp-in-string "\r\n\.\r\n$" "\r\n" string))
+ (str-no-cr (replace-regexp-in-string "\r" "" str-no-period)))
+ (dolist (line (split-string str-no-cr "\n"))
+ (unless (= (length line) 0)
+ (elpher-insert-index-record line)))))
(defun elpher-insert-margin (&optional type-name)
"Insert index margin, optionally containing the TYPE-NAME, into the current buffer."
(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)))
+ (port (elt fields 3)))
+ (elpher-insert-index-record-helper type display-string selector host port)))
+
+(defun elpher-insert-index-record-helper (type display-string selector host port)
+ (let ((address (elpher-make-address 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))
'elpher-node (elpher-make-node elpher-current-node
address
getter)
+ 'elpher-node-type type
'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
- (insert (propertize display-string
- 'face 'elpher-info)))
- (?h (elpher-insert-margin "W") ; Web link
+ (?i (elpher-insert-margin) ;; Information
+ (insert (propertize
+ (if elpher-buttonify-urls-in-directories
+ (elpher-buttonify-urls display-string)
+ 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
'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)))))
(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)))
+
+(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))))
+
;;; Selector retrieval (all kinds)
;;
(if content
(progn
(elpher-with-clean-buffer
- (insert content))
- (elpher-restore-pos))
+ (insert content)
+ (elpher-restore-pos)))
(if address
(progn
(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
- (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
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)
(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-process-text elpher-selector-string))
+ (elpher-restore-pos)
+ (elpher-set-node-content elpher-current-node
+ (buffer-string))))))))))
;; Image retrieval
(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
'no-conversion)
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 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: "))
(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)))))))))
+;;; Bookmarks
+;;
+
+(defun elpher-make-bookmark (type display-string address)
+ (list type display-string address))
+
+(defun elpher-bookmark-type (bookmark)
+ (elt bookmark 0))
+
+(defun elpher-bookmark-display-string (bookmark)
+ (elt bookmark 1))
+
+(defun elpher-bookmark-address (bookmark)
+ (elt bookmark 2))
+
+(defun elpher-save-bookmarks (bookmarks)
+ (with-temp-file (locate-user-emacs-file "elpher-bookmarks")
+ (erase-buffer)
+ (pp bookmarks (current-buffer))))
-;;; Navigation procedures
+(defun elpher-load-bookmarks ()
+ (with-temp-buffer
+ (insert-file-contents (locate-user-emacs-file "elpher-bookmarks"))
+ (goto-char (point-min))
+ (read (current-buffer))))
+
+(defun elpher-add-bookmark (bookmark)
+ (let ((bookmarks (elpher-load-bookmarks)))
+ (add-to-list 'bookmarks bookmark)
+ (elpher-save-bookmarks bookmarks)))
+
+(defun elpher-remove-bookmark (bookmark)
+ (elpher-save-bookmarks
+ (seq-filter (lambda (this-bookmark)
+ (not (equal bookmark this-bookmark)))
+ (elpher-load-bookmarks))))
+
+(defun elpher-display-bookmarks ()
+ (interactive)
+ (elpher-with-clean-buffer
+ (insert
+ "---- Bookmark list ----\n\n"
+ "Use 'u' to return to the previous page.\n\n")
+ (dolist (bookmark (elpher-load-bookmarks))
+ (let ((type (elpher-bookmark-type bookmark))
+ (display-string (elpher-bookmark-display-string bookmark))
+ (address (elpher-bookmark-address bookmark)))
+ (elpher-insert-index-record-helper type display-string
+ (elpher-address-selector address)
+ (elpher-address-host address)
+ (elpher-address-port address))))
+ (goto-char (point-min))
+ (elpher-next-link)))
+
+(defun elpher-bookmark-link ()
+ "Bookmark the link at point."
+ (interactive)
+ (let ((button (button-at (point))))
+ (if button
+ (let ((node (button-get button 'elpher-node))
+ (type (button-get button 'elpher-node-type)))
+ (if node
+ (elpher-add-bookmark
+ (elpher-make-bookmark type
+ (button-label button)
+ (elpher-node-address node)))
+ (error "Can only bookmark gopher links, not general URLs.")))
+ (error "No link selected."))))
+
+(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))
+ (type (button-get button 'elpher-node-type)))
+ (if node
+ (elpher-remove-bookmark
+ (elpher-make-bookmark type
+ (button-label button)
+ (elpher-node-address node)))
+ (error "Can only bookmark gopher links, not general URLs.")))
+ (error "No link selected."))))
+
+;;; Interactive navigation 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)
+ (switch-to-buffer "*elpher*")
(let* (
(hostname (read-string "Gopher host: "))
(selector (read-string "Selector (default none): " nil nil ""))
(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."
(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."))))
+ (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 (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))))
+ (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 "" host port)))
+ (elpher-visit-node (elpher-make-node elpher-current-node
+ root-address
+ #'elpher-get-index-node)))
+ (error "Already at root directory of current server.")))
+ (error "Command invalid for Elpher start page."))))
+
+
;;; 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 "d") 'elpher-download)
(define-key map (kbd "m") 'elpher-menu)
(when (fboundp 'evil-define-key)
- (evil-define-key 'normal map
+ (add-to-list 'evil-motion-state-modes 'elpher-mode)
+ (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 "m") 'elpher-menu))
+ (kbd "m") 'elpher-menu
+ (kbd "a") 'elpher-bookmark-link
+ (kbd "x") 'elpher-unbookmark-link
+ (kbd "B") 'elpher-display-bookmarks))
map)
"Keymap for gopher client.")
(defun elpher ()
"Start elpher with default landing page."
(interactive)
- (setq elpher-current-node nil)
- (let ((start-node (elpher-make-node nil
- elpher-start-address
- #'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 nil
+ elpher-start-address
+ #'elpher-get-index-node)))
+ (elpher-visit-node start-node)))
"Started Elpher.") ; Otherwise (elpher) evaluates to start page string.
;;; elpher.el ends here