X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=elopher.el;h=eb5160ce90040f70b5d387601ccf79d42f42177b;hb=5a6848b978627f5643fca2011212ff10c2f823e4;hp=fd0e91029ff9c6a9110a3f97de39e4b8d4f896b8;hpb=4e8af883d7ef57fad6fbfa8b26ba20d42f4ff343;p=elpher.git

diff --git a/elopher.el b/elopher.el
index fd0e910..eb5160c 100644
--- a/elopher.el
+++ b/elopher.el
@@ -6,51 +6,376 @@
 
 ;;; Code:
 
-;; (defvar elopher-mode-map nil "Keymap for gopher client.")
-;; (define-key elopher-mode-map (kbd "p") 'elopher-quit)
+;;; Global constants
+;;
 
-;; (define-derived-mode elopher-mode special-mode "elopher"
-;;   "Major mode for elopher, an elisp gopher client.")
+(defconst elopher-version "1.0.0"
+  "Current version of elopher.")
 
-(defvar my-marker nil)
+(defconst elopher-margin-width 6
+  "Width of left-hand margin used when rendering indicies.")
 
-(defun my-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)
-        (insert (propertize string 'face '(foreground-color . "yellow")))
-        (set-marker marker (point))))))
-    
+(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"))
 
-(defun elopher ()
-  "Start gopher client."
-  (interactive)
-  (switch-to-buffer-other-window "*elopher*")
-  (setq my-marker (make-marker))
-  (erase-buffer)
-  (make-process
-   :name "date"
-   :command (list "/bin/ls" "-l" "/")
-   :filter #'my-filter))
-
-(elopher)
+
+;;; Customization group
+;;
+
+(defgroup elopher nil
+  "A simple gopher client."
+  :group 'applications)
+
+(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.")
+
+;;; Model
+;;
+
+;; Address
+
+(defun elopher-make-address (selector host port)
+  (list selector host port))
+
+(defun elopher-address-selector (address)
+  (car address))
+
+(defun elopher-address-host (address)
+  (cadr address))
+
+(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
+;;
+
+(defun elopher-prepare-buffer ()
+  (switch-to-buffer "*elopher*")
+  (elopher-mode)
+  (let ((inhibit-read-only t))
+    (erase-buffer)))
+
+
+;;; 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
+      (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-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))
+         (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
+                              'face elopher-info-face)))
+      (?0 (elopher-insert-margin "T")
+          (insert-text-button display-string
+                              'face elopher-text-face
+                              'elopher-node (elopher-make-node elopher-current-node
+                                                               address
+                                                               #'elopher-get-text-node)
+                              'action #'elopher-click-link
+                              'follow-link t
+                              'help-echo help-string))
+      (?1 (elopher-insert-margin "/")
+          (insert-text-button display-string
+                              'face elopher-index-face
+                              'elopher-node (elopher-make-node elopher-current-node
+                                                               address
+                                                               #'elopher-get-index-node)
+                              'action #'elopher-click-link
+                              'follow-link t
+                              'help-echo help-string))
+      ((or ?g ?p ?I) (elopher-insert-margin "im")
+          (insert-text-button display-string
+                              '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")))
+
+
+;;; Selector retrieval (all kinds)
+;;
+
+(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 (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-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-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
+
+(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)))))))
+        
   
-  ;; (address (read-from-minibuffer "Address of gopher server: ")))
-  ;; (message "Connecting to '%s' ..." address)
-  ;; (erase-buffer)
-  ;; (insert (propertize "Hello, world." 'face '(foreground-color . "red")))
-  ;; (newline)
-  ;; (insert (propertize "Hello, Tim." 'face '(foreground-color . "yellow"))))
-
-(defun elopher-quit ()
+
+;;; Navigation procedures
+;;
+
+(defun elopher-next-link ()
   (interactive)
-  (kill-buffer "*elopher*"))
+  (forward-button 1))
 
-(start-process "ls" "*elopher*" "/bin/date")
+(defun elopher-prev-link ()
+  (interactive)
+  (backward-button 1))
 
-;;; elopher.el ends here
+(defun elopher-click-link (button)
+  (let ((node (button-get button 'elopher-node)))
+    (elopher-visit-node node)))
 
-(list-processes)
+(defun elopher-follow-closest-link ()
+  (interactive)
+  (push-button))
+
+(defun elopher-go ()
+  "Go to a particular gopher site."
+  (interactive)
+  (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))))
+
+(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)
+  (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