X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=elopher.el;h=30383ae57d06cac614df92c55db204873937f533;hb=2a3908c9deef367de80495ffeae94e46329ee67a;hp=609876db1876a03eae17f6a8e7ae84f3768f1480;hpb=e4e93510ae1b8adac371c955ff600afbade58c05;p=elpher.git

diff --git a/elopher.el b/elopher.el
index 609876d..30383ae 100644
--- a/elopher.el
+++ b/elopher.el
@@ -6,31 +6,91 @@
 
 ;;; 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))
@@ -41,108 +101,185 @@
     (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