X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=elopher.el;h=eb5160ce90040f70b5d387601ccf79d42f42177b;hb=5a6848b978627f5643fca2011212ff10c2f823e4;hp=56dc32f25f9c81ace0f18ca260b395214f8ca874;hpb=0935ba5c8e9541272bf3acda9bc5b948640c3ac3;p=elpher.git

diff --git a/elopher.el b/elopher.el
index 56dc32f..eb5160c 100644
--- a/elopher.el
+++ b/elopher.el
@@ -6,6 +6,41 @@
 
 ;;; Code:
 
+;;; 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.")
+
+(defconst elopher-start-index
+  (string-join
+   (list "i\tfake\tfake\t1"
+         "i--------------------------------------------\tfake\tfake\t1"
+         "i          Elopher Gopher Client             \tfake\tfake\t1"
+         (format "i              version %s\tfake\tfake\t1" elopher-version)
+         "i--------------------------------------------\tfake\tfake\t1"
+         "i\tfake\tfake\t1"
+         "iBasic usage:\tfake\tfake\t1"
+         "i - tab/shift-tab: next/prev directory entry\tfake\tfake\t1"
+         "i - RET/mouse-1: open directory entry\tfake\tfake\t1"
+         "i - u: return to parent directory entry\tfake\tfake\t1"
+         "i - g: go to a particular site\tfake\tfake\t1"
+         "i - r: reload current page\tfake\tfake\t1"
+         "i\tfake\tfake\t1"
+         "iPlaces to start exploring Gopherspace:\tfake\tfake\t1"
+         "1Floodgap Systems Gopher Server\t\tgopher.floodgap.com\t70"
+         "1Super-Dimensional Fortress\t\tsdf.org\t70"
+         "i\tfake\tfake\t1"
+         "iTest entries:\tfake\tfake\t1"
+         "pXKCD comic image\t/fun/xkcd/comics/2130/2137/text_entry.png\tgopher.floodgap.com\t70"
+         "1Test server\t\tlocalhost\t70"
+         ".")
+   "\r\n"))
+
+
 ;;; Customization group
 ;;
 
@@ -23,82 +58,121 @@
   "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 variables
+;;; Model
 ;;
 
-(defvar elopher-version "1.0.0"
-  "Current version of elopher.")
+;; Address
 
-(defvar elopher-margin-width 6
-  "Width of left-hand margin used when rendering indicies.")
+(defun elopher-make-address (selector host port)
+  (list selector host port))
 
-(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"
-          "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"))
+(defun elopher-address-selector (address)
+  (car address))
 
+(defun elopher-address-host (address)
+  (cadr address))
 
-;;; Mode and keymap
+(defun elopher-address-port (address)
+  (caddr address))
+
+;; Node
+
+(defun elopher-make-node (parent address getter &optional content pos)
+  (list parent address getter content pos))
+
+(defun elopher-node-parent (node)
+  (elt node 0))
+
+(defun elopher-node-address (node)
+  (elt node 1))
+
+(defun elopher-node-getter (node)
+  (elt node 2))
+
+(defun elopher-node-content (node)
+  (elt node 3))
+
+(defun elopher-node-pos (node)
+  (elt node 4))
+
+(defun elopher-set-node-content (node content)
+  (setcar (nthcdr 3 node) content))
+
+(defun elopher-set-node-pos (node pos)
+  (setcar (nthcdr 4 node) pos))
+
+(defun elopher-save-pos ()
+  (when elopher-current-node
+    (elopher-set-node-pos elopher-current-node (point))))
+
+(defun elopher-restore-pos ()
+  (let ((pos (elopher-node-pos elopher-current-node)))
+    (if pos
+        (goto-char pos)
+      (goto-char (point-min)))))
+
+;; Node graph traversal
+
+(defvar elopher-current-node)
+
+(defun elopher-visit-node (node)
+  (elopher-save-pos)
+  (elopher-prepare-buffer)
+  (setq elopher-current-node node)
+  (funcall (elopher-node-getter node)))
+
+(defun elopher-visit-parent-node ()
+  (let ((parent-node (elopher-node-parent elopher-current-node)))
+    (when parent-node
+      (elopher-visit-node parent-node))))
+      
+(defun elopher-reload-current-node ()
+  (elopher-set-node-content elopher-current-node nil)
+  (elopher-visit-node elopher-current-node))
+
+
+;;; Buffer preparation
 ;;
 
-(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.")
+(defun elopher-prepare-buffer ()
+  (switch-to-buffer "*elopher*")
+  (elopher-mode)
+  (let ((inhibit-read-only t))
+    (erase-buffer)))
 
-(define-derived-mode elopher-mode special-mode "elopher"
-  "Major mode for elopher, an elisp gopher client.")
 
 ;;; Index rendering
 ;;
 
+(defun elopher-insert-index (string)
+  "Inserts the index corresponding to STRING into the current buffer."
+  (dolist (line (split-string string "\r\n"))
+    (unless (string-empty-p line)
+      (elopher-insert-index-record line))))
+
 (defun elopher-insert-margin (&optional type-name)
+  "Insert index margin, optionally containing the TYPE-NAME, into the current buffer."
   (if type-name
-      (insert (propertize
-               (format (concat "%" (number-to-string elopher-margin-width) "s")
-                       (concat "[" type-name "] "))
-               'face elopher-margin-face))
+      (progn
+        (insert (format (concat "%" (number-to-string (- elopher-margin-width 1)) "s")
+                        (concat
+                         (propertize "[" 'face '(foreground-color . "blue"))
+                         (propertize type-name 'face '(foreground-color . "white"))
+                         (propertize "]" 'face '(foreground-color . "blue")))))
+        (insert " "))
     (insert (make-string elopher-margin-width ?\s))))
 
-(defun elopher-render-record (line)
+(defun elopher-insert-index-record (line)
+  "Inserts the index record corresponding to LINE into the current buffer."
   (let* ((type (elt line 0))
          (fields (split-string (substring line 1) "\t"))
          (display-string (elt fields 0))
-         (selector (elt fields 1))
-         (hostname (elt fields 2))
-         (port (elt fields 3))
-         (address (list selector hostname port)))
+         (address (elopher-make-address (elt fields 1) (elt fields 2) (elt fields 3)))
+         (help-string (format "mouse-1, RET: open %s on %s port %s"
+                              (elopher-address-selector address)
+                              (elopher-address-host address)
+                              (elopher-address-port address))))
     (pcase type
       (?i (elopher-insert-margin)
           (insert (propertize display-string
@@ -106,121 +180,130 @@
       (?0 (elopher-insert-margin "T")
           (insert-text-button display-string
                               'face elopher-text-face
-                              'link-getter #'elopher-get-text
-                              'link-address address
+                              'elopher-node (elopher-make-node elopher-current-node
+                                                               address
+                                                               #'elopher-get-text-node)
                               'action #'elopher-click-link
-                              'follow-link t))
+                              'follow-link t
+                              'help-echo help-string))
       (?1 (elopher-insert-margin "/")
           (insert-text-button display-string
                               'face elopher-index-face
-                              'link-getter #'elopher-get-index
-                              'link-address address
+                              'elopher-node (elopher-make-node elopher-current-node
+                                                               address
+                                                               #'elopher-get-index-node)
                               'action #'elopher-click-link
-                              'follow-link t))
-      (?p (elopher-insert-margin "img")
+                              'follow-link t
+                              'help-echo help-string))
+      ((or ?g ?p ?I) (elopher-insert-margin "im")
           (insert-text-button display-string
-                             'face elopher-image-face
-                             'link-getter #'elopher-get-image
-                             'link-address address
-                             'action #'elopher-click-link
-                             'follow-link t))
+                              'face elopher-image-face
+                              'elopher-node (elopher-make-node elopher-current-node
+                                                               address
+                                                               #'elopher-get-image-node)
+                              'action #'elopher-click-link
+                              'follow-link t
+                              'help-echo help-string))
       (?.) ; Occurs at end of index, can safely ignore.
       (tp (elopher-insert-margin (concat (char-to-string tp) "?"))
           (insert (propertize display-string
                               'face elopher-unknown-face))))
     (insert "\n")))
 
-(defvar elopher-incomplete-record "")
-
-(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-render-record line)))
-        (setq elopher-incomplete-record (elt lines idx))))))
 
-;;; Selector retrieval
+;;; 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)
-  (let ((inhibit-read-only t))
-    (erase-buffer))
+(defvar elopher-selector-string)
+
+(defun elopher-get-selector (address after &optional binary)
+  "Retrieve selector specified by ADDRESS and store it in the
+string elopher-selector-string, then execute AFTER as the
+sentinal function."
+  (setq elopher-selector-string "")
+  (let ((p (get-process "elopher-process")))
+    (if p (delete-process p)))
   (make-network-process
    :name "elopher-process"
-   :host host
-   :service (if port port 70)
-   :filter filter
-   :sentinel sentinel)
-  (process-send-string "elopher-process" (concat selector "\n")))
+   :host (elopher-address-host address)
+   :service (elopher-address-port address)
+   :filter (lambda (proc string)
+             (setq elopher-selector-string (concat elopher-selector-string string)))
+   :sentinel after)
+  (process-send-string "elopher-process"
+                       (concat (elopher-address-selector address) "\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))
+(defun elopher-get-index-node ()
+  (let ((content (elopher-node-content elopher-current-node))
+        (address (elopher-node-address elopher-current-node)))
+    (if content
+        (progn
+          (let ((inhibit-read-only t))
+            (insert content))
+          (elopher-restore-pos))
+      (if address
+          (elopher-get-selector address
+                                (lambda (proc event)
+                                  (let ((inhibit-read-only t))
+                                    (elopher-insert-index elopher-selector-string))
+                                  (elopher-restore-pos)
+                                  (elopher-set-node-content elopher-current-node
+                                                            (buffer-string))))
+        (progn
+          (let ((inhibit-read-only t))
+            (elopher-insert-index elopher-start-index))
+          (elopher-restore-pos)
+          (elopher-set-node-content elopher-current-node
+                                    (buffer-string)))))))
 
 ;; Text retrieval
 
-(defun elopher-text-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)
-      (dolist (line (split-string string "\r"))
-        (insert line))
-      (set-marker marker (point)))))
-
-(defun elopher-get-text (selector host port)
-  (elopher-get-selector selector host port
-                        #'elopher-text-filter))
+(defun elopher-strip-CRs (string)
+  (replace-regexp-in-string "\r" "" string))
+
+(defun elopher-get-text-node ()
+  (let ((content (elopher-node-content elopher-current-node))
+        (address (elopher-node-address elopher-current-node)))
+    (if content
+        (progn
+          (let ((inhibit-read-only t))
+            (insert content))
+          (elopher-restore-pos))
+      (elopher-get-selector address
+                            (lambda (proc event)
+                              (let ((inhibit-read-only t))
+                                (insert (elopher-strip-CRs elopher-selector-string)))
+                              (elopher-restore-pos)
+                              (elopher-set-node-content elopher-current-node
+                                                        (buffer-string)))))))
 
 ;; 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)
-  (setq elopher-image-buffer "")
-  (elopher-get-selector selector host port
-                        #'elopher-image-filter
-                        #'elopher-image-sentinel))
-
-;;; Control methods for binding
+(defun elopher-get-image-node ()
+  (let ((content (elopher-node-content elopher-current-node))
+        (address (elopher-node-address elopher-current-node)))
+    (if content
+        (progn
+          (let ((inhibit-read-only t))
+            (insert-image content))
+          (elopher-restore-pos))
+      (elopher-get-selector address
+                            (lambda (proc event)
+                              (let ((image (create-image
+                                            (string-as-unibyte elopher-selector-string)
+                                            nil t))
+                                    (inhibit-read-only t))
+                                (insert-image image)
+                                (elopher-restore-pos)
+                                (elopher-set-node-content elopher-current-node image)))))))
+        
+  
+
+;;; Navigation procedures
 ;;
 
-(defun elopher-history-back ()
-  (interactive)
-  (when elopher-history
-    (let ((inhibit-read-only t))
-      (erase-buffer)
-      (save-excursion
-        (insert (pop elopher-history))))))
-
 (defun elopher-next-link ()
   (interactive)
   (forward-button 1))
@@ -230,7 +313,8 @@
   (backward-button 1))
 
 (defun elopher-click-link (button)
-  (apply (button-get button 'link-getter) (button-get button 'link-address)))
+  (let ((node (button-get button 'elopher-node)))
+    (elopher-visit-node node)))
 
 (defun elopher-follow-closest-link ()
   (interactive)
@@ -239,24 +323,59 @@
 (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-visit-node
+     (elopher-make-node elopher-current-node
+                        address
+                        #'elopher-get-index-node))))
 
-;;; Main start procedure
+(defun  elopher-reload ()
+  "Reload current site."
+  (interactive)
+  (elopher-reload-current-node))
+
+(defun elopher-back ()
+  "Go to previous site."
+  (interactive)
+  (if (elopher-node-parent elopher-current-node)
+      (elopher-visit-parent-node)
+    (message "No previous site.")))
+
+
+;;; 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-back)
+    (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-back
+        (kbd "u") 'elopher-back
+        (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.")
+
+
+;;; 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)
-;; (elopher-get-index "" "gopher.floodgap.com" 70)
-;; (elopher-get-image "/fun/xkcd/comics/2130/2137/text_entry.png" "gopher.floodgap.com" 70)
+  (setq elopher-current-node nil)
+  (let ((start-node (elopher-make-node nil nil #'elopher-get-index-node)))
+    (elopher-visit-node start-node)))
 
 ;;; elopher.el ends here