;; 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"
"iUsage:\tfake\tfake\t1"
"i\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.")
(?I elpher-get-image-node "im" elpher-image)
(?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)
- (?7 elpher-get-search-node "?" elpher-search))
+ (?h elpher-get-url-node "W" elpher-url))
"Association list from types to getters, margin codes and index faces.")
'((t :inherit org-level-6))
"Face used for url type directory records.")
+(defface elpher-telnet
+ '((t :inherit org-level-6))
+ "Face used for telnet type directory records.")
+
(defface elpher-binary
'((t :inherit org-level-7))
"Face used for binary type directory records.")
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
;;
'(erase-buffer))
args)))
+
;;; Index rendering
;;
"Insert the index corresponding to STRING into the current buffer."
;; 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))))
+ (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."
(insert " "))
(insert (make-string elpher-margin-width ?\s))))
+(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-node-getter node) #'elpher-get-url-node)
+ (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 (line)
"Insert the index record corresponding to LINE into the current buffer."
(let* ((type (elt line 0))
(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)
+ "Helper 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.
+
+This function is essentially the second half of `elpher-insert-index-record',
+but broken out so that it can be used by other functions to construct indices
+on the fly."
+ (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))
- (face (caddr type-map-entry)))
+ (let* ((getter (car type-map-entry))
+ (margin-code (cadr type-map-entry))
+ (face (caddr type-map-entry))
+ (node (elpher-make-node elpher-current-node address getter)))
(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
+ 'elpher-node-type type
'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.
+ (insert (propertize
+ (if elpher-buttonify-urls-in-directories
+ (elpher-buttonify-urls display-string)
+ display-string)
+ 'face 'elpher-info)))
(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)))
+
;;; Selector retrieval (all kinds)
;;
;; 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 selector host port))
+ (getter (car (alist-get type elpher-type-map))))
+ (elpher-make-node elpher-current-node address getter))
+ (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 selector host port))
+ (getter (car (alist-get ?h elpher-type-map))))
+ (elpher-make-node elpher-current-node address getter)))))
+
+
(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)
(message (format "Download complate, saved to file %s."
elpher-download-filename)))))))))
+;; URL retrieval
+
+(defun elpher-get-url-node ()
+ "Getter which attempts to open the URL specified by the current node."
+ (let* ((address (elpher-node-address elpher-current-node))
+ (selector (elpher-address-selector address)))
+ (elpher-visit-parent-node) ; Do first in case of non-local exits.
+ (let ((url (elt (split-string selector "URL:") 1)))
+ (if elpher-open-urls-with-eww
+ (browse-web url)
+ (browse-url url)))))
+
+;; Telnet node connection
+
+(defun elpher-get-telnet-node ()
+ "Getter which opens a telnet connection to the server specified by the current node."
+ (let* ((address (elpher-node-address elpher-current-node))
+ (host (elpher-address-host address))
+ (port (elpher-address-port address)))
+ (elpher-visit-parent-node)
+ (telnet host port)))
-;;; Navigation procedures
+
+;;; 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))))
+
+(defun elpher-load-bookmarks ()
+ (with-temp-buffer
+ (ignore-errors
+ (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
+ "Use 'u' to return to the previous page.\n\n"
+ "---- Bookmark list ----\n\n")
+ (let ((bookmarks (elpher-load-bookmarks)))
+ (if bookmarks
+ (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))))
+ (insert "No bookmarks found.\n")))
+ (insert "\n-----------------------")
+ (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))
+ (label (button-label button)))
+ (if node
+ (progn
+ (elpher-add-bookmark
+ (elpher-make-bookmark type
+ label
+ (elpher-node-address node)))
+ (message "Bookmarked \"%s\"" label))
+ (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 ""))
- (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 (read-string "Port (default 70): " nil nil 70)))
+ (elpher-make-node elpher-current-node
+ (elpher-make-address selector host-or-url port)
+ #'elpher-get-index-node))))))
+ (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."
(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."
(elpher-visit-node (elpher-make-node elpher-current-node
root-address
#'elpher-get-index-node)))
- (message "Already at root directory of current server.")))
- (message "Command invalid for Elpher start page."))))
+ (error "Already at root directory of current server")))
+ (error "Command invalid for Elpher start page"))))
+
;;; Mode and keymap
;;
(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 "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)
- (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))
+ (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
The Lambda Lab / projects / elpher.git / blobdiff