;;; Code:
-;; (defvar elopher-mode-map nil "Keymap for gopher client.")
+;;; Customization group
+;;
-;; (define-derived-mode elopher-mode special-mode "elopher"
-;; "Major mode for elopher, an elisp gopher client.")
+(defgroup elopher nil
+ "A simple gopher client."
+ :group 'applications)
-(defvar elopher-margin-width 5)
+
+(defcustom elopher-index-face '(foreground-color . "cyan")
+ "Face used for index records.")
+(defcustom elopher-text-face '(foreground-color . "white")
+ "Face used for text records.")
+(defcustom elopher-info-face '(foreground-color . "gray")
+ "Face used for info records.")
+(defcustom elopher-image-face '(foreground-color . "green")
+ "Face used for image records.")
+(defcustom elopher-unknown-face '(foreground-color . "red")
+ "Face used for unknown record types.")
+(defcustom elopher-margin-face '(foreground-color . "orange")
+ "Face used for record margin legend.")
+
+;;; Global constants
+;;
+
+(defconst elopher-version "1.0.0"
+ "Current version of elopher.")
+
+(defconst elopher-margin-width 6
+ "Width of left-hand margin used when rendering indicies.")
+
+(defvar elopher-start-page
+ (concat "i\tfake\tfake\t1\r\n"
+ "i--------------------------------------------\tfake\tfake\t1\r\n"
+ "i Elopher Gopher Client \tfake\tfake\t1\r\n"
+ (format "i version %s\tfake\tfake\t1\r\n" elopher-version)
+ "i--------------------------------------------\tfake\tfake\t1\r\n"
+ "i\tfake\tfake\t1\r\n"
+ "iBasic usage:\tfake\tfake\t1\r\n"
+ "i - tab/shift-tab: next/prev directory entry\tfake\tfake\t1\r\n"
+ "i - RET/mouse-1: open directory entry\tfake\tfake\t1\r\n"
+ "i - u: return to parent directory entry\tfake\tfake\t1\r\n"
+ "i - g: go to a particular site\tfake\tfake\t1\r\n"
+ "i\tfake\tfake\t1\r\n"
+ "iPlaces to start exploring Gopherspace:\tfake\tfake\t1\r\n"
+ "1Floodgap Systems Gopher Server\t\tgopher.floodgap.com\t70\r\n"
+ "1Super-Dimensional Fortress\t\tsdf.org\t70\r\n"
+ "i\tfake\tfake\t1\r\n"
+ "iTest entries:\tfake\tfake\t1\r\n"
+ "pXKCD comic image\t/fun/xkcd/comics/2130/2137/text_entry.png\tgopher.floodgap.com\t70\r\n"))
+
+
+;;; Mode and keymap
+;;
+
+(defvar elopher-mode-map
+ (let ((map (make-sparse-keymap)))
+ (define-key map (kbd "<tab>") 'elopher-next-link)
+ (define-key map (kbd "<S-tab>") 'elopher-prev-link)
+ (define-key map (kbd "u") 'elopher-history-back)
+ (define-key map (kbd "g") 'elopher-go)
+ (when (require 'evil nil t)
+ (evil-define-key 'normal map
+ (kbd "C-]") 'elopher-follow-closest-link
+ (kbd "C-t") 'elopher-history-back
+ (kbd "u") 'elopher-history-back
+ (kbd "g") 'elopher-go))
+ map)
+ "Keymap for gopher client.")
+
+(define-derived-mode elopher-mode special-mode "elopher"
+ "Major mode for elopher, an elisp gopher client.")
+
+
+;;; Index rendering
+;;
(defun elopher-insert-margin (&optional type-name)
(if type-name
(insert (propertize
(format (concat "%" (number-to-string elopher-margin-width) "s")
(concat "[" type-name "] "))
- 'face '(foreground-color . "yellow")))
+ 'face elopher-margin-face))
(insert (make-string elopher-margin-width ?\s))))
-(defun elopher-follow-index-link (button)
- (apply #'elopher-get-index (button-get button 'link-address)))
-
-(defun elopher-follow-text-link (button)
- (apply #'elopher-get-text (button-get button 'link-address)))
-
-(defun elopher-follow-image-link (button)
- (apply #'elopher-get-image (button-get button 'link-address)))
-
-(defun elopher-process-record (line)
+(defun elopher-render-record (line)
(let* ((type (elt line 0))
(fields (split-string (substring line 1) "\t"))
(display-string (elt fields 0))
(pcase type
(?i (elopher-insert-margin)
(insert (propertize display-string
- 'face '(foreground-color. "white"))))
+ 'face elopher-info-face)))
(?0 (elopher-insert-margin "T")
(insert-text-button display-string
- 'face '(foreground-color . "gray")
+ 'face elopher-text-face
+ 'link-getter #'elopher-get-text
'link-address address
- 'action #'elopher-follow-text-link
+ 'action #'elopher-click-link
'follow-link t))
(?1 (elopher-insert-margin "/")
(insert-text-button display-string
- 'face '(foreground-color . "cyan")
+ 'face elopher-index-face
+ 'link-getter #'elopher-get-index
'link-address address
- 'action #'elopher-follow-index-link
+ 'action #'elopher-click-link
'follow-link t))
(?p (elopher-insert-margin "img")
(insert-text-button display-string
- 'face '(foreground-color . "gray")
+ 'face elopher-image-face
+ 'link-getter #'elopher-get-image
'link-address address
- 'action #'elopher-follow-image-link
+ 'action #'elopher-click-link
'follow-link t))
(?.) ; Occurs at end of index, can safely ignore.
(tp (elopher-insert-margin (concat (char-to-string tp) "?"))
(insert (propertize display-string
- 'face '(foreground-color . "red")))))
+ 'face elopher-unknown-face))))
(insert "\n")))
(defvar elopher-incomplete-record "")
-(defun elopher-process-complete-records (string)
+(defun elopher-render-complete-records (string)
(let* ((til-now (string-join (list elopher-incomplete-record string)))
(lines (split-string til-now "\r\n")))
(dotimes (idx (length lines))
(if (< idx (- (length lines) 1))
(let ((line (elt lines idx)))
(unless (string-empty-p line)
- (elopher-process-record line)))
+ (elopher-render-record line)))
(setq elopher-incomplete-record (elt lines idx))))))
-(defun elopher-index-filter (proc string)
- (with-current-buffer (get-buffer "*elopher*")
- (let ((marker (process-mark proc)))
- (if (not (marker-position marker))
- (set-marker marker 0 (current-buffer)))
- (save-excursion
- (goto-char marker)
- (elopher-process-complete-records string)
- (set-marker marker (point))))))
-
-(defun elopher-get-index (selector host port)
+
+;;; History management
+;;
+
+(defvar elopher-history nil
+ "List of pages in elopher history.")
+
+(defun elopher-push-history ()
+ "Add current contents of buffer, including point, to history."
+ (unless (string-empty-p (buffer-string))
+ (push
+ (list (buffer-string)
+ (point))
+ elopher-history)))
+
+(defun elopher-pop-history ()
+ "Restore most recent page from history."
+ (interactive)
+ (if (get-buffer "*elopher*")
+ (if elopher-history
+ (let* ((inhibit-read-only t)
+ (prev-page (pop elopher-history))
+ (page-string (car prev-page))
+ (page-point (cadr prev-page)))
+ (switch-to-buffer "*elopher*")
+ (erase-buffer)
+ (insert page-string)
+ (goto-char page-point))
+ (message "Already at start of history."))
+ (message "No elopher buffer found.")))
+
+
+;;; Selector retrieval (all kinds)
+;;
+
+
+(defun elopher-get-selector (selector host port filter &optional sentinel)
(switch-to-buffer "*elopher*")
- (erase-buffer)
- (setq elopher-incomplete-record "")
+ (elopher-mode)
+ (elopher-push-history)
+ (let ((inhibit-read-only t))
+ (erase-buffer))
(make-network-process
:name "elopher-process"
:host host
:service (if port port 70)
- :filter #'elopher-index-filter)
+ :filter filter
+ :sentinel sentinel)
(process-send-string "elopher-process" (concat selector "\n")))
+;; Index retrieval
+
+(defun elopher-index-filter (proc string)
+ (let ((marker (process-mark proc))
+ (inhibit-read-only t))
+ (if (not (marker-position marker))
+ (set-marker marker 0 (current-buffer)))
+ (save-excursion
+ (goto-char marker)
+ (elopher-render-complete-records string)
+ (set-marker marker (point)))))
+
+(defun elopher-get-index (selector host port)
+ (setq elopher-incomplete-record "")
+ (elopher-get-selector selector host port
+ #'elopher-index-filter))
+
+;; Text retrieval
+
(defun elopher-text-filter (proc string)
- (with-current-buffer (get-buffer "*elopher*")
- (let ((marker (process-mark proc)))
- (if (not (marker-position marker))
- (set-marker marker 0 (current-buffer)))
- (save-excursion
- (goto-char marker)
- (dolist (line (split-string string "\r"))
- (insert line))
- (set-marker marker (point))))))
+ (let ((marker (process-mark proc))
+ (inhibit-read-only t))
+ (if (not (marker-position marker))
+ (set-marker marker 0 (current-buffer)))
+ (save-excursion
+ (goto-char marker)
+ (dolist (line (split-string string "\r"))
+ (insert line))
+ (set-marker marker (point)))))
(defun elopher-get-text (selector host port)
- (switch-to-buffer "*elopher*")
- (erase-buffer)
- (make-network-process
- :name "elopher-process"
- :host host
- :service port
- :filter #'elopher-text-filter)
- (process-send-string "elopher-process" (concat selector "\n")))
+ (elopher-get-selector selector host port
+ #'elopher-text-filter))
+
+;; Image retrieval
(defvar elopher-image-buffer "")
(defun elopher-image-filter (proc string)
(setq elopher-image-buffer (concat elopher-image-buffer string)))
+(defun elopher-image-sentinel (proc event)
+ (let ((inhibit-read-only t))
+ (insert-image (create-image elopher-image-buffer))))
+
(defun elopher-get-image (selector host port)
- (switch-to-buffer "*elopher*")
- (erase-buffer)
(setq elopher-image-buffer "")
- (make-network-process
- :name "elopher-process"
- :host host
- :service port
- :filter #'elopher-image-filter)
- (process-send-string "elopher-process" (concat selector "\n"))
- (insert-image (create-image elopher-image-buffer)))
+ (elopher-get-selector selector host port
+ #'elopher-image-filter
+ #'elopher-image-sentinel))
-(defun elopher ()
- "Start gopher client."
+
+;;; Navigation methods
+;;
+
+(defun elopher-next-link ()
+ (interactive)
+ (forward-button 1))
+
+(defun elopher-prev-link ()
+ (interactive)
+ (backward-button 1))
+
+(defun elopher-click-link (button)
+ (apply (button-get button 'link-getter) (button-get button 'link-address)))
+
+(defun elopher-follow-closest-link ()
+ (interactive)
+ (push-button))
+
+(defun elopher-go ()
+ "Go to a particular gopher site."
(interactive)
(elopher-get-index "" (read-from-minibuffer "Gopher host: ") 70))
-(elopher-get-index "" "cosmic.voyage" 70)
-;; (elopher-get-image "/fun/xkcd/comics/2130/2137/text_entry.png" "gopher.floodgap.com" 70)
+
+;;; Main start procedure
+;;
+
+(defun elopher ()
+ "Start elopher with default landing page."
+ (interactive)
+ (switch-to-buffer "*elopher*")
+ (elopher-mode)
+ (setq elopher-history nil)
+ (let ((inhibit-read-only t))
+ (erase-buffer)
+ (save-excursion
+ (elopher-render-complete-records elopher-start-page))))
+
;;; elopher.el ends here