X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=elopher.el;h=fe30d930c4a33ae946a2f1deb76a59b41bd4e40b;hb=ed720255e09b70bb0105a1684ab2ea046df2b4e3;hp=2907e95b8d5afef539fc08c04e2283c0c0493733;hpb=3d8242afb97973597d318ed0fdc558b51ceffa20;p=elpher.git

diff --git a/elopher.el b/elopher.el
index 2907e95..fe30d93 100644
--- a/elopher.el
+++ b/elopher.el
@@ -6,139 +6,442 @@
 
 ;;; Code:
 
-(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)
-    (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))
-    map)
-  "Keymap for gopher client.")
+;;; 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.")
+
+(defconst elopher-margin-width 6
+  "Width of left-hand margin used when rendering indicies.")
+
+(defconst elopher-start-index
+  (mapconcat
+   'identity
+   (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\tfake\tfake\t1"
+         "i - tab/shift-tab: next/prev directory entry on current page\tfake\tfake\t1"
+         "i - RET/mouse-1: open directory entry under cursor\tfake\tfake\t1"
+         "i - u: return to parent directory entry\tfake\tfake\t1"
+         "i - g: go to a particular page\tfake\tfake\t1"
+         "i - r: reload current page\tfake\tfake\t1"
+         "i - d: download directory entry under cursor\tfake\tfake\t1"
+         "i - w: display the raw server response for the current page\tfake\tfake\t1"
+         "i\tfake\tfake\t1"
+         "iPlaces to start exploring Gopherspace:\tfake\tfake\t1"
+         "i\tfake\tfake\t1"
+         "1Floodgap Systems Gopher Server\t\tgopher.floodgap.com\t70"
+         "i\tfake\tfake\t1"
+         "iAlternatively, select the following item and enter some\tfake\tfake\t1"
+         "isearch terms:\tfake\tfake\t1"
+         "i\tfake\tfake\t1"
+         "7Veronica-2 Gopher Search Engine\t/v2/vs\tgopher.floodgap.com\t70"
+         ".")
+   "\r\n"))
+
+
+;;; Customization group
+;;
+
+(defgroup elopher nil
+  "A simple gopher client."
+  :group 'applications)
+
+(defcustom elopher-index-face '(foreground-color . "cyan")
+  "Face used for index records."
+  :type '(face))
+
+(defcustom elopher-text-face '(foreground-color . "white")
+  "Face used for text records."
+  :type '(face))
+
+(defcustom elopher-info-face '(foreground-color . "gray")
+  "Face used for info records."
+  :type '(face))
+
+(defcustom elopher-image-face '(foreground-color . "green")
+  "Face used for image records."
+  :type '(face))
+
+(defcustom elopher-search-face '(foreground-color . "orange")
+  "Face used for image records."
+  :type '(face))
+
+(defcustom elopher-http-face '(foreground-color . "yellow")
+  "Face used for image records."
+  :type '(face))
+
+(defcustom elopher-unknown-face '(foreground-color . "red")
+  "Face used for unknown record types."
+  :type '(face))
+
+(defcustom elopher-open-urls-with-eww nil
+  "If non-nil, open URL selectors using eww.
+Otherwise, use the system browser via the BROWSE-URL function."
+  :type '(boolean))
+
+;;; Model
+;;
+
+;; Address
+
+(defun elopher-make-address (selector host port)
+  (list selector host port))
 
-(defvar elopher-margin-width 5)
+(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 &optional getter)
+  (elopher-save-pos)
+  (elopher-process-cleanup)
+  (setq elopher-current-node node)
+  (if getter
+      (funcall getter)
+    (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
+;;
+
+(defmacro elopher-with-clean-buffer (&rest args)
+  "Evaluate ARGS with a clean *elopher* buffer as current."
+  (list 'progn
+        '(switch-to-buffer "*elopher*")
+        '(elopher-mode)
+        (append (list 'let '((inhibit-read-only t))
+                      '(erase-buffer))
+                args)))
+
+;;; Index rendering
+;;
+
+(defun elopher-insert-index (string)
+  "Insert the index corresponding to STRING into the current buffer."
+  (dolist (line (split-string string "\r\n"))
+    (unless (= (length line) 0)
+      (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 '(foreground-color . "yellow")))
+      (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-process-record (line)
+(defun elopher-insert-index-record (line)
+  "Insert 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))
+         (host (elt fields 2))
          (port (elt fields 3))
-         (address (list selector hostname port)))
+         (address (elopher-make-address selector host port))
+         (help-string (format "mouse-1, RET: open %s on %s port %s"
+                              selector host port)))
     (pcase type
       (?i (elopher-insert-margin)
           (insert (propertize display-string
-                              'face '(foreground-color. "gray"))))
+                              'face elopher-info-face)))
       (?0 (elopher-insert-margin "T")
           (insert-text-button display-string
-                              'face '(foreground-color . "white")
-                              'link-getter #'elopher-get-text
-                              'link-address address
+                              'face elopher-text-face
+                              '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 '(foreground-color . "yellow")
-                              'link-getter #'elopher-get-index
-                              'link-address address
+                              'face elopher-index-face
+                              '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 '(foreground-color . "cyan")
-                             '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))
+      (?7 (elopher-insert-margin "S")
+          (insert-text-button display-string
+                              'face elopher-search-face
+                              'elopher-node (elopher-make-node elopher-current-node
+                                                              address
+                                                              #'elopher-get-search-node)
+                              'action #'elopher-click-link
+                              'follow-link t
+                              'help-echo help-string))
+      (?h (elopher-insert-margin "W")
+          (let ((url (elt (split-string selector "URL:") 1)))
+            (insert-text-button display-string
+                                'face elopher-http-face
+                                'elopher-url url
+                                'action #'elopher-click-url
+                                'follow-link t
+                                'help-echo (format "mouse-1, RET: open url %s" url))))
       (?.) ; 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)
-  (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)))
-        (setq elopher-incomplete-record (elt lines idx))))))
-
-(defun elopher-get-selector (selector host port filter)
-  (switch-to-buffer "*elopher*")
-  (elopher-mode)
-  (let ((inhibit-read-only t))
-    (erase-buffer))
-  (setq elopher-incomplete-record "")
+
+;;; Selector retrieval (all kinds)
+;;
+
+(defun elopher-process-cleanup ()
+  "Immediately shut down any extant elopher process."
+  (let ((p (get-process "elopher-process")))
+    (if p (delete-process p))))
+
+(defvar elopher-selector-string)
+
+(defun elopher-get-selector (address after)
+  "Retrieve selector specified by ADDRESS, then execute AFTER.
+The result is stored as a string in the variable elopher-selector-string."
+  (setq elopher-selector-string "")
   (make-network-process
    :name "elopher-process"
-   :host host
-   :service (if port port 70)
-   :filter filter)
-  (process-send-string "elopher-process" (concat selector "\n")))
-
-(defun elopher-index-filter (proc string)
-  (with-current-buffer (get-buffer "*elopher*")
-    (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-process-complete-records string)
-        (set-marker marker (point))))))
-    
-(defun elopher-get-index (selector host port)
-  (elopher-get-selector selector host port #'elopher-index-filter))
-
-(defun elopher-text-filter (proc string)
-  (with-current-buffer (get-buffer "*elopher*")
-    (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))
-
-(defvar elopher-image-buffer "")
-
-(defun elopher-image-filter (proc string)
-  (setq elopher-image-buffer (concat elopher-image-buffer string)))
-
-(defun elopher-get-image (selector host port)
-  (setq elopher-image-buffer "")
-  (elopher-get-selector selector host port #'elopher-image-filter)
-  (insert-image (create-image elopher-image-buffer)))
-
-(defun elopher-history-back ()
-  (interactive)
-  (let ((inhibit-read-only t))
-    (undo)))
+   :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
+          (elopher-with-clean-buffer
+           (insert content))
+          (elopher-restore-pos))
+      (if address
+          (progn
+            (elopher-with-clean-buffer
+             (insert "LOADING DIRECTORY..."))
+            (elopher-get-selector address
+                                  (lambda (proc event)
+                                    (unless (string-prefix-p "deleted" event)
+                                      (message event)
+                                      (elopher-with-clean-buffer
+                                       (elopher-insert-index elopher-selector-string))
+                                      (elopher-restore-pos)
+                                      (elopher-set-node-content elopher-current-node
+                                                                (buffer-string))))))
+        (progn
+          (elopher-with-clean-buffer
+           (elopher-insert-index elopher-start-index))
+          (elopher-restore-pos)
+          (elopher-set-node-content elopher-current-node
+                                    (buffer-string)))))))
+
+;; Text retrieval
+
+(defun elopher-process-text (string)
+  (let ((chopped-str (replace-regexp-in-string "\r\n\.\r\n$" "\r\n" string)))
+    (replace-regexp-in-string "\r" "" chopped-str)))
+
+(defun elopher-get-text-node ()
+  (let ((content (elopher-node-content elopher-current-node))
+        (address (elopher-node-address elopher-current-node)))
+    (if content
+        (progn
+          (elopher-with-clean-buffer
+           (insert content))
+          (elopher-restore-pos))
+      (progn
+        (elopher-with-clean-buffer
+         (insert "LOADING TEXT..."))
+        (elopher-get-selector address
+                              (lambda (proc event)
+                                (unless (string-prefix-p "deleted" event)
+                                  (elopher-with-clean-buffer
+                                   (insert (elopher-process-text 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
+          (elopher-with-clean-buffer
+           (insert-image content))
+          (setq cursor-type nil)
+          (elopher-restore-pos))
+      (progn
+        (elopher-with-clean-buffer
+         (insert "LOADING IMAGE..."))
+        (elopher-get-selector address
+                              (lambda (proc event)
+                                (unless (string-prefix-p "deleted" event)
+                                  (let ((image (create-image
+                                                (string-as-unibyte elopher-selector-string)
+                                                nil t)))
+                                    (elopher-with-clean-buffer
+                                     (insert-image image))
+                                    (setq cursor-type nil)
+                                    (elopher-restore-pos)
+                                    (elopher-set-node-content elopher-current-node
+                                                              image)))))))))
+
+;; Search retrieval
+
+(defun elopher-get-search-node ()
+  (let* ((content (elopher-node-content elopher-current-node))
+         (address (elopher-node-address elopher-current-node)))
+    (if content
+        (progn
+          (elopher-with-clean-buffer
+            (insert content))
+          (elopher-restore-pos)
+          (message "Displaying cached search results.  Reload to perform a new search."))
+      (let* ((query-string (read-string "Query: "))
+             (query-selector (concat (elopher-address-selector address) "\t" query-string))
+             (search-address (elopher-make-address query-selector
+                                                   (elopher-address-host address)
+                                                   (elopher-address-port address))))
+        (elopher-with-clean-buffer
+         (insert "LOADING RESULTS..."))
+        (elopher-get-selector search-address
+                              (lambda (proc event)
+                                (unless (string-prefix-p "deleted" event)
+                                  (elopher-with-clean-buffer
+                                   (elopher-insert-index elopher-selector-string))
+                                  (goto-char (point-min))
+                                  (elopher-set-node-content elopher-current-node
+                                                            (buffer-string)))))))))
+
+;; Raw server response retrieval
+
+(defun elopher-get-node-raw ()
+  (let* ((content (elopher-node-content elopher-current-node))
+         (address (elopher-node-address elopher-current-node)))
+    (elopher-with-clean-buffer
+     (insert "LOADING RAW SERVER RESPONSE..."))
+    (if address
+        (elopher-get-selector address
+                              (lambda (proc event)
+                                (unless (string-prefix-p "deleted" event)
+                                  (elopher-with-clean-buffer
+                                   (insert elopher-selector-string))
+                                  (goto-char (point-min)))))
+      (progn
+        (elopher-with-clean-buffer
+         (insert elopher-start-index))
+        (goto-char (point-min)))))
+  (message "Displaying raw server response.  Reload to return to standard view."))
+ 
+
+;; File export retrieval
+
+(defvar elopher-download-filename)
+
+(defun elopher-get-node-download ()
+  (let* ((address (elopher-node-address elopher-current-node))
+         (selector (elopher-address-selector address)))
+    (unwind-protect
+        (let* ((filename-proposal (file-name-nondirectory selector))
+               (filename (read-file-name "Save file as: "
+                                         nil nil nil
+                                         (if (> (length filename-proposal) 0)
+                                             filename-proposal
+                                           "gopher.file"))))
+          (message "Downloading...")
+          (setq elopher-download-filename filename)
+          (elopher-get-selector address
+                                (lambda (proc event)
+                                  (let ((coding-system-for-write 'binary))
+                                    (with-temp-file elopher-download-filename
+                                      (insert elopher-selector-string)))
+                                  (message (format "Download complate, saved to file %s."
+                                                   elopher-download-filename)))))
+      (elopher-visit-parent-node))))
+        
+
+;;; Navigation procedures
+;;
 
 (defun elopher-next-link ()
   (interactive)
@@ -149,18 +452,98 @@
   (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-click-url (button)
+  (let ((url (button-get button 'elopher-url)))
+    (if elopher-open-urls-with-eww
+        (browse-web url)
+      (browse-url url))))
 
 (defun elopher-follow-closest-link ()
   (interactive)
   (push-button))
 
-(defun elopher ()
-  "Start gopher client."
+(defun elopher-go ()
+  "Go to a particular gopher site."
+  (interactive)
+  (let* (
+         (hostname (read-string "Gopher host: "))
+         (selector (read-string "Selector (default none): " nil nil ""))
+         (port (read-string "Port (default 70): " nil nil 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 page."
   (interactive)
-  (elopher-get-index "" (read-from-minibuffer "Gopher host: ") 70))
+  (elopher-reload-current-node))
 
-(elopher-get-index "" "gopher.floodgap.com" 70)
-;; (elopher-get-image "/fun/xkcd/comics/2130/2137/text_entry.png" "gopher.floodgap.com" 70)
+(defun elopher-view-raw ()
+  "View current page as plain text."
+  (interactive)
+  (elopher-visit-node elopher-current-node
+                      #'elopher-get-node-raw))
+
+(defun elopher-back ()
+  "Go to previous site."
+  (interactive)
+  (if (elopher-node-parent elopher-current-node)
+      (elopher-visit-parent-node)
+    (message "No previous site.")))
+
+(defun elopher-download ()
+  "Download the link at point."
+  (interactive)
+  (let ((button (button-at (point))))
+    (if button
+        (elopher-visit-node (button-get button 'elopher-node)
+                            #'elopher-get-node-download)
+      (message "No link selected."))))
+
+
+;;; 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)
+    (define-key map (kbd "w") 'elopher-view-raw)
+    (define-key map (kbd "d") 'elopher-download)
+    (when (fboundp 'evil-define-key)
+      (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
+        (kbd "w") 'elopher-view-raw
+        (kbd "d") 'elopher-download))
+    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))
+  "Started Elopher.") ; Otherwise (elopher) evaluates to start page string.
 
 ;;; elopher.el ends here
+