Gopher links in text files are now clickable.
[elpher.git] / elopher.el
index 8237b63..21552e0 100644 (file)
   "Face used for image records."
   :type '(face))
 
+(defcustom elopher-binary-face '(foreground-color . "magenta")
+  "Face used for image records."
+  :type '(face))
+
 (defcustom elopher-unknown-face '(foreground-color . "red")
   "Face used for unknown record types."
   :type '(face))
@@ -145,6 +149,7 @@ Otherwise, use the system browser via the BROWSE-URL function."
 
 (defun elopher-visit-node (node &optional getter)
   (elopher-save-pos)
+  (elopher-process-cleanup)
   (setq elopher-current-node node)
   (if getter
       (funcall getter)
@@ -163,6 +168,7 @@ Otherwise, use the system browser via the BROWSE-URL function."
 ;;
 
 (defmacro elopher-with-clean-buffer (&rest args)
+  "Evaluate ARGS with a clean *elopher* buffer as current."
   (list 'progn
         '(switch-to-buffer "*elopher*")
         '(elopher-mode)
@@ -191,6 +197,16 @@ Otherwise, use the system browser via the BROWSE-URL function."
         (insert " "))
     (insert (make-string elopher-margin-width ?\s))))
 
+(defvar elopher-type-map
+  `((?0 elopher-get-text-node "T" ,elopher-text-face)
+    (?1 elopher-get-index-node "/" ,elopher-index-face)
+    (?g elopher-get-image-node "im" ,elopher-image-face)
+    (?p elopher-get-image-node "im" ,elopher-image-face)
+    (?I elopher-get-image-node "im" ,elopher-image-face)
+    (?4 elopher-get-binary-node "B" ,elopher-binary-face)
+    (?9 elopher-get-binary-node "B" ,elopher-binary-face)
+    (?7 elopher-get-search-node "?" ,elopher-search-face)))
+
 (defun elopher-insert-index-record (line)
   "Insert the index record corresponding to LINE into the current buffer."
   (let* ((type (elt line 0))
@@ -200,74 +216,54 @@ Otherwise, use the system browser via the BROWSE-URL function."
          (host (elt fields 2))
          (port (elt fields 3))
          (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 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")
+         (type-map-entry (alist-get type elopher-type-map)))
+    (if type-map-entry
+        (let ((getter (car type-map-entry))
+              (margin-code (cadr type-map-entry))
+              (face (caddr type-map-entry)))
+          (elopher-insert-margin margin-code)
           (insert-text-button display-string
-                              'face elopher-image-face
+                              'face 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)
+                                                               getter)
                               '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 elopher-unknown-face))))
+                              'help-echo (format "mouse-1, RET: open %s on %s port %s"
+                                                 selector host port)))
+      (pcase type
+        (?i (elopher-insert-margin) ; Information 
+            (insert (propertize display-string
+                                'face elopher-info-face)))
+        (?h (elopher-insert-margin "W") ; Web link
+            (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 elopher-unknown-face)))))
     (insert "\n")))
 
 
 ;;; 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 "")
-  (let ((p (get-process "elopher-process")))
-    (if p (delete-process p)))
   (make-network-process
    :name "elopher-process"
    :host (elopher-address-host address)
@@ -286,7 +282,7 @@ The result is stored as a string in the variable elopher-selector-string."
     (if content
         (progn
           (elopher-with-clean-buffer
-            (insert content))
+           (insert content))
           (elopher-restore-pos))
       (if address
           (progn
@@ -294,23 +290,64 @@ The result is stored as a string in the variable elopher-selector-string."
              (insert "LOADING DIRECTORY..."))
             (elopher-get-selector address
                                   (lambda (proc event)
-                                    (elopher-with-clean-buffer
-                                      (elopher-insert-index elopher-selector-string))
-                                    (elopher-restore-pos)
-                                    (elopher-set-node-content elopher-current-node
-                                                              (buffer-string)))))
+                                    (unless (string-prefix-p "deleted" 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-insert-index elopher-start-index))
           (elopher-restore-pos)
           (elopher-set-node-content elopher-current-node
                                     (buffer-string)))))))
 
 ;; Text retrieval
 
+(defvar elopher-url-regex "\\(https?\\|gopher\\)://\\([a-z.\-]+\\)\\(?3::[0-9]+\\)?\\(?4:/[^ \r\n\t(),]*\\)")
+
+(defun elopher-buttonify-urls (string)
+  "Turn substrings which look like urls in STRING into clickable buttons."
+  (with-temp-buffer
+    (insert string)
+    (goto-char (point-min))
+    (while (re-search-forward elopher-url-regex nil t)
+      (let ((url (match-string 0))
+            (protocol (downcase (match-string 1))))
+        (if (string= protocol "gopher")
+            (let* ((host (match-string 2))
+                   (port 70)
+                   (type-and-selector (match-string 4))
+                   (type (if (> (length type-and-selector) 1)
+                             (elt type-and-selector 1)
+                           ?1))
+                   (selector (if (> (length type-and-selector) 1)
+                                 (substring type-and-selector 2)
+                               ""))
+                   (address (elopher-make-address selector host port))
+                   (getter (car (alist-get type elopher-type-map))))
+              (make-text-button (match-beginning 0)
+                                (match-end 0)
+                                'elopher-node (elopher-make-node elopher-current-node
+                                                                 address
+                                                                 getter)
+                                'action #'elopher-click-link
+                                'follow-link t
+                                'help-echo (format "mouse-1, RET: open %s on %s port %s"
+                                                   selector host port)))
+          (make-text-button (match-beginning 0)
+                            (match-end 0)
+                            'elopher-url url
+                            'action #'elopher-click-url
+                            'follow-link t
+                            'help-echo (format "mouse-1, RET: open url %s" url)))))
+    (buffer-string)))
+
 (defun elopher-process-text (string)
-  (let ((chopped-str (replace-regexp-in-string "\r\n\.\r\n$" "\r\n" string)))
-    (replace-regexp-in-string "\r" "" chopped-str)))
+  (let* ((chopped-str (replace-regexp-in-string "\r\n\.\r\n$" "\r\n" string))
+         (cleaned-str (replace-regexp-in-string "\r" "" chopped-str)))
+    (elopher-buttonify-urls cleaned-str)))
 
 (defun elopher-get-text-node ()
   (let ((content (elopher-node-content elopher-current-node))
@@ -318,18 +355,19 @@ The result is stored as a string in the variable elopher-selector-string."
     (if content
         (progn
           (elopher-with-clean-buffer
-            (insert content))
+           (insert content))
           (elopher-restore-pos))
       (progn
         (elopher-with-clean-buffer
-          (insert "LOADING TEXT..."))
+         (insert "LOADING TEXT..."))
         (elopher-get-selector address
                               (lambda (proc event)
-                                (elopher-with-clean-buffer
-                                  (insert (elopher-process-text elopher-selector-string)))
-                                (elopher-restore-pos)
-                                (elopher-set-node-content elopher-current-node
-                                                          (buffer-string))))))))
+                                (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
 
@@ -339,22 +377,24 @@ The result is stored as a string in the variable elopher-selector-string."
     (if content
         (progn
           (elopher-with-clean-buffer
-            (insert-image content))
+           (insert-image content))
           (setq cursor-type nil)
           (elopher-restore-pos))
       (progn
         (elopher-with-clean-buffer
-          (insert "LOADING IMAGE..."))
+         (insert "LOADING IMAGE..."))
         (elopher-get-selector address
                               (lambda (proc 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))))))))
+                                (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
 
@@ -376,11 +416,12 @@ The result is stored as a string in the variable elopher-selector-string."
          (insert "LOADING RESULTS..."))
         (elopher-get-selector search-address
                               (lambda (proc event)
-                                (elopher-with-clean-buffer
-                                  (elopher-insert-index elopher-selector-string))
-                                (goto-char (point-min))
-                                (elopher-set-node-content elopher-current-node
-                                                          (buffer-string))))))))
+                                (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
 
@@ -392,9 +433,10 @@ The result is stored as a string in the variable elopher-selector-string."
     (if address
         (elopher-get-selector address
                               (lambda (proc event)
-                                (elopher-with-clean-buffer
-                                 (insert elopher-selector-string))
-                                (goto-char (point-min))))
+                                (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))
@@ -409,24 +451,23 @@ The result is stored as a string in the variable elopher-selector-string."
 (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)))
+    (elopher-visit-parent-node) ; Do first in case of non-local exits.
+    (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))))
-        
+                                                   elopher-download-filename)))))))))
+
 
 ;;; Navigation procedures
 ;;