ASCII export: Better link export.

Links with description not create a note before the next headline that
contains the link.  In the text, the description will be shown.

The new variable `org-export-ascii-links-to-notes' can be configured
to turn off this behavior, then the reference will be inserted inline
in the text.  If the line becomes too long because of this, it will
be wrapped.

lisp/ChangeLog

@@ -1,3 +1,10 @@
+2009-02-26  Carsten Dominik  <carsten.dominik@gmail.com>
+
+	* org-exp.el (org-export-ascii-links-to-notes): New option.
+	(org-export-as-ascii): Handle links better.
+	(org-export-ascii-wrap, org-export-ascii-push-links): New
+	functions.
+
 2009-02-25  Carsten Dominik  <carsten.dominik@gmail.com>
 
 	* org-agenda.el (org-agenda): Make prefix arg optional.

lisp/org-exp.el

@@ -498,6 +498,13 @@ Org-mode file."
   :group 'org-export-ascii
   :type '(repeat character))
 
+(defcustom org-export-ascii-links-to-notes t
+  "Non-nil means, convert links to notes before the next headline.
+When nil, the link will be exported in place.  If the line becomes long
+in this way, it will be wrapped."
+  :group 'org-export-ascii
+  :type 'boolean)
+
 (defgroup org-export-xml nil
   "Options specific for XML export of Org-mode files."
   :tag "Org Export XML"
@@ -2664,7 +2671,7 @@ underlined headlines.  The default is 3."
 		  :add-text (plist-get opt-plist :text))
 		 "\n"))
 	 thetoc have-headings first-heading-pos
-	 table-open table-buffer link desc)
+	 table-open table-buffer link-buffer link desc rpl wrap)
     (let ((inhibit-read-only t))
       (org-unmodified
        (remove-text-properties (point-min) (point-max)
@@ -2773,12 +2780,17 @@ underlined headlines.  The default is 3."
 
     (org-init-section-numbers)
     (while (setq line (pop lines))
+      (when (and link-buffer (string-match "^\\*+ " line))
+	(org-export-ascii-push-links link-buffer)
+	(setq link-buffer nil))
+      (setq wrap nil)
       ;; Remove the quoted HTML tags.
       (setq line (org-html-expand-for-ascii line))
       ;; Replace links with the description when possible
       (while (string-match org-bracket-link-regexp line)
 	(setq link (match-string 1 line)
-	      desc (match-string (if (match-end 3) 3 1) line))
+	      desc0 (match-string 3 line)
+	      desc (or desc0 (match-string 1 line)))
 	(if (and (> (length link) 8)
 		 (equal (substring link 0 8) "coderef:"))
 	    (setq line (replace-match
@@ -2787,9 +2799,16 @@ underlined headlines.  The default is 3."
 				      (substring link 8)
 				      org-export-code-refs)))
 			t t line))
-	  (setq line (replace-match
-		      (if (match-end 3) "[\\3]" "[\\1]")
-		      t nil line))))
+	  (setq rpl (concat "[" 
+			    (or (match-string 3 line) (match-string 1 line))
+			    "]"))
+	  (when (and desc0 (not (equal desc0 link)))
+	    (if org-export-ascii-links-to-notes
+		(push (cons desc0 link) link-buffer)
+	      (setq rpl (concat rpl " (" link ")")
+		    wrap (+ (length line) (- (length (match-string 0)))
+			    (length desc)))))
+	  (setq line (replace-match rpl t t line))))
       (when custom-times
 	(setq line (org-translate-time line)))
       (cond
@@ -2825,9 +2844,12 @@ underlined headlines.  The default is 3."
 	    (setq line (replace-match "" t t line)))
 	(if (and org-export-with-fixed-width
 		 (string-match "^\\([ \t]*\\)\\(:\\( \\|$\\)\\)" line))
-	    (setq line (replace-match "\\1" nil nil line)))
+	    (setq line (replace-match "\\1" nil nil line))
+	  (if wrap (setq line (org-export-ascii-wrap line wrap))))
 	(insert line "\n"))))
 
+    (org-export-ascii-push-links link-buffer)
+
     (normal-mode)
 
     ;; insert the table of contents
@@ -2877,8 +2899,8 @@ underlined headlines.  The default is 3."
     (goto-char (match-beginning 2))
     (delete-char 1) (insert "`")
     (goto-char (match-end 2)))
-  (goto-char (point-min))
   ;; Remove target markers
+  (goto-char (point-min))
   (while (re-search-forward  "<<<?\\([^<>]*\\)>>>?\\([ \t]*\\)" nil t)
     (replace-match "\\1\\2")))
 
@@ -2907,6 +2929,37 @@ underlined headlines.  The default is 3."
 	(setq line (replace-match "" nil nil line))))
   line)
 
+
+(defun org-export-ascii-wrap (line where)
+  "Wrap LINE at or before WHERE."
+  (let ((ind (org-get-indentation line))
+	pos)
+    (catch 'found
+      (loop for i from where downto (/ where 2) do
+	    (and (equal (aref line i) ?\ )
+		 (setq pos i)
+		 (throw 'found t))))
+    (if pos
+	(concat (substring line 0 pos) "\n"
+		(make-string ind ?\ )
+		(substring line (1+ pos)))
+      line)))
+			   
+(defun org-export-ascii-push-links (link-buffer)
+  "Push out links in the buffer."
+  (when link-buffer
+    ;; We still have links to push out.
+    (insert "\n")
+    (let ((ind ""))
+      (save-match-data
+	(if (save-excursion
+	      (re-search-backward
+	       "^\\(\\([ \t]*\\)\\|\\(\\*+ \\)\\)[^ \t\n]" nil t))
+	    (setq ind (or (match-string 2)
+			  (make-string (length (match-string 3)) ?\ )))))
+      (mapc (lambda (x) (insert ind "[" (car x) "]: " link)) link-buffer))
+    (insert "\n")))
+
 (defun org-insert-centered (s &optional underline)
   "Insert the string S centered and underline it with character UNDERLINE."
   (let ((ind (max (/ (- fill-column (string-width s)) 2) 0)))