Implementing reload.

[elpher.git] / elopher.el

diff --git a/elopher.el b/elopher.el
index 56dc32f..3aef080 100644 (file)
--- a/elopher.el
+++ b/elopher.el
@@ -26,18 +26,15 @@
 (defcustom elopher-margin-face '(foreground-color . "orange")
   "Face used for record margin legend.")
 
-;;; Global variables
+;;; Global constants
 ;;
 
-(defvar elopher-version "1.0.0"
+(defconst elopher-version "1.0.0"
   "Current version of elopher.")
 
-(defvar elopher-margin-width 6
+(defconst elopher-margin-width 6
   "Width of left-hand margin used when rendering indicies.")
 
-(defvar elopher-history nil
-  "List of pages in elopher history.")
-
 (defvar elopher-start-page
   (concat "i\tfake\tfake\t1\r\n"
           "i--------------------------------------------\tfake\tfake\t1\r\n"
@@ -62,24 +59,27 @@
 ;;; Mode and keymap
 ;;
 
-(defvar elopher-mode-map
+(setq 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 "u") 'elopher-pop-history)
     (define-key map (kbd "g") 'elopher-go)
+    (define-key map (kbd "r") 'elopher-reload)
     (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.")
+        (kbd "C-t") 'elopher-pop-history
+        (kbd "u") 'elopher-pop-history
+        (kbd "g") 'elopher-go
+        (kbd "r") 'elopher-reload))
+    map))
+  ;; "Keymap for gopher client.")
 
 (define-derived-mode elopher-mode special-mode "elopher"
   "Major mode for elopher, an elisp gopher client.")
 
+
 ;;; Index rendering
 ;;
 
@@ -142,13 +142,55 @@
               (elopher-render-record line)))
         (setq elopher-incomplete-record (elt lines idx))))))
 
-;;; Selector retrieval
+
+;;; History management
+;;
+
+(defvar elopher-history nil
+  "List of pages in elopher history.")
+
+(defvar elopher-place-history nil
+  "List of objects describing how to access pages in history.")
+
+(defvar elopher-current-place nil
+  "How to access current page.")
+
+(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)
+    (push
+     elopher-current-place
+     elopher-place-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)
+            (setq elopher-current-place (pop elopher-place-history)))
+        (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*")
-  (push (buffer-string) elopher-history)
   (elopher-mode)
+  (elopher-push-history)
   (let ((inhibit-read-only t))
     (erase-buffer))
   (make-network-process
@@ -210,16 +252,17 @@
                         #'elopher-image-filter
                         #'elopher-image-sentinel))
 
-;;; Control methods for binding
-;;
+;; Start page retrieval
 
-(defun elopher-history-back ()
-  (interactive)
-  (when elopher-history
-    (let ((inhibit-read-only t))
-      (erase-buffer)
-      (save-excursion
-        (insert (pop elopher-history))))))
+(defun elopher-get-start-page (&optional selector host port)
+  "Display start page.  SELECTOR, HOST and PORT are unused."
+  (let ((inhibit-read-only t))
+    (erase-buffer)
+    (save-excursion
+      (elopher-render-complete-records elopher-start-page))))
+
+;;; Navigation methods
+;;
 
 (defun elopher-next-link ()
   (interactive)
@@ -230,7 +273,8 @@
   (backward-button 1))
 
 (defun elopher-click-link (button)
-  (apply (button-get button 'link-getter) (button-get button 'link-address)))
+  (apply (button-get button 'link-getter) (button-get button 'link-address))
+  (setq elopher-current-place (list link-getter link-address)))
 
 (defun elopher-follow-closest-link ()
   (interactive)
@@ -239,7 +283,21 @@
 (defun elopher-go ()
   "Go to a particular gopher site."
   (interactive)
-  (elopher-get-index "" (read-from-minibuffer "Gopher host: ") 70))
+  (let* ((selector "")
+         (hostname (read-from-minibuffer "Gopher host: "))
+         (port 70)
+         (address (list selector hostname port)))
+    (elopher-get-index "" (read-from-minibuffer "Gopher host: ") 70)i
+    (setq elopher-current-place (list #'elopher-get-index address))))
+
+(defun  elopher-reload ()
+  "Reload current page."
+  (interactive)
+  (if elopher-current-place
+      (let ((link-getter (car elopher-current-place))
+            (address (cadr elopher-current-place)))
+        (apply link-getter address))
+    (elopher-get-start-page)))
 
 ;;; Main start procedure
 ;;
@@ -250,13 +308,9 @@
   (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))))
+  (setq elopher-place-history nil)
+  (setq elopher-current-place nil)
+  (elopher-get-start-page))
 
-;; (elopher)
-;; (elopher-get-index "" "gopher.floodgap.com" 70)
-;; (elopher-get-image "/fun/xkcd/comics/2130/2137/text_entry.png" "gopher.floodgap.com" 70)
 
 ;;; elopher.el ends here