ox-bibtex: Port for "org-exp-bibtex.el"

* contrib/lisp/ox-bibtex.el: New file

contrib/lisp/ox-bibtex.el

@@ -0,0 +1,252 @@
+;;; ox-bibtex.el --- Export bibtex fragments
+
+;; Copyright (C) 2009-2013 Taru Karttunen
+
+;; Author: Taru Karttunen <taruti@taruti.net>
+;;      Nicolas Goaziou <n dot goaziou at gmail dot com>
+;; This file is not currently part of GNU Emacs.
+
+;; This program is free software; you can redistribute it and/or
+;; modify it under the terms of the GNU General Public License as
+;; published by the Free Software Foundation; either version 2, or (at
+;; your option) any later version.
+
+;; This program is distributed in the hope that it will be useful, but
+;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+;; General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this program ; see the file COPYING.  If not, write to
+;; the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+;; Boston, MA 02111-1307, USA.
+
+;;; Commentary:
+;;
+;; This is an utility to handle BibTeX export to both LaTeX and html
+;; exports.  It uses the bibtex2html software from:
+;;
+;;   http://www.lri.fr/~filliatr/bibtex2html/
+;;
+;; The usage is as follows:
+;;
+;;   #+BIBLIOGRAPHY: bibfilebasename stylename optional-options
+;;
+;; e.g. given foo.bib and using style plain:
+;;
+;;   #+BIBLIOGRAPHY: foo plain option:-d
+;;
+;; Optional options are of the form:
+;;
+;;   option:-foobar pass '-foobar' to bibtex2html
+;;
+;; e.g.,
+;;
+;;   option:-d    sort by date
+;;   option:-a    sort as BibTeX (usually by author) *default*
+;;   option:-u    unsorted i.e. same order as in .bib file
+;;   option:-r    reverse the sort
+;;
+;; See the bibtex2html man page for more.  Multiple options can be
+;; combined like:
+;;
+;;   option:-d option:-r
+;;
+;; Limiting to only the entries cited in the document:
+;;
+;;   limit:t
+;;
+;; For LaTeX export this simply inserts the lines
+;;
+;;   \bibliographystyle{plain}
+;;   \bibliography{foo}
+;;
+;; into the TeX file when exporting.
+;;
+;; For HTML export it:
+;; 1) converts all \cite{foo} to links to the bibliography,
+;; 2) creates a foo.html and foo_bib.html,
+;; 3) includes the contents of foo.html in the exported HTML file.
+
+
+;;; Internal Functions
+
+(defun org-bibtex-get-file (keyword)
+  "Return bibliography file as a string.
+KEYWORD is a \"BIBLIOGRAPHY\" keyword. If no file is found,
+return nil instead."
+  (let ((value (org-element-property :value keyword)))
+    (and value
+         (string-match "\\(\\S-+\\)[ \t]+\\(\\S-+\\)\\(.*\\)" value)
+         (match-string 1 value))))
+
+(defun org-bibtex-get-style (keyword)
+  "Return bibliography style as a string.
+KEYWORD is a \"BIBLIOGRAPHY\" keyword. If no style is found,
+return nil instead."
+  (let ((value (org-element-property :value keyword)))
+    (and value
+         (string-match "\\(\\S-+\\)[ \t]+\\(\\S-+\\)\\(.*\\)" value)
+         (match-string 2 value))))
+
+(defun org-bibtex-get-arguments (keyword)
+  "Return \"bibtex2html\" arguments specified by the user.
+KEYWORD is a \"BIBLIOGRAPHY\" keyword. Return value is a plist
+containing `:options' and `:limit' properties. The former
+contains a list of strings to be passed as options ot
+\"bibtex2html\" process. The latter contains a boolean."
+  (let ((value (org-element-property :value keyword)))
+    (and value
+         (string-match "\\(\\S-+\\)[ \t]+\\(\\S-+\\)\\(.*\\)" value)
+         (let (options limit)
+           (dolist (arg (org-split-string (match-string 3 value))
+                        ;; Return value.
+                        (list :options (nreverse options) :limit limit))
+             (let* ((s (split-string arg ":"))
+                    (key (car s))
+                    (value (nth 1 s)))
+               (cond ((equal "limit" key)
+                      (setq limit (not (equal "nil" value))))
+                     ((equal "option" key) (push value options)))))))))
+
+(defun org-bibtex-citation-p (fragment)
+  "Non-nil when a LaTeX macro is a citation.
+FRAGMENT is a `latex-fragment' type object."
+  (string-match "\\`\\\\cite{" (org-element-property :value fragment)))
+
+(defun org-bibtex-get-citation-key (citation)
+  "Return key for a given citation, as a string.
+CITATION is a `latex-fragment' type object satisfying to
+`org-bibtex-citation-p' predicate."
+  (let ((value (org-element-property :value citation)))
+    (and (string-match "\\`\\\\cite{" value)
+         (substring value (match-end 0) -1))))
+
+
+
+;;; LaTeX Part
+
+(defadvice org-latex-keyword (around bibtex-keyword)
+  "Translate \"BIBLIOGRAPHY\" keywords into LaTeX syntax.
+Fallback to `latex' back-end for other keywords."
+  (let ((keyword (ad-get-arg 0)))
+    (if (not (equal (org-element-property :key keyword) "BIBLIOGRAPHY"))
+        ad-do-it
+      (let ((file (org-bibtex-get-file keyword))
+            (style (org-bibtex-get-style keyword)))
+        (setq ad-return-value
+              (when file
+                (concat (and style (format "\\bibliographystyle{%s}\n" style))
+                        (format "\\bibliography{%s}" file))))))))
+
+(ad-activate 'org-latex-keyword)
+
+
+
+;;; HTML Part
+
+(defvar org-bibtex-html-entries-alist)  ; Dynamically scoped.
+(defvar org-bibtex-html-keywords-alist) ; Dynamically scoped.
+
+
+;;;; Advices
+
+(defadvice org-html-keyword (around bibtex-keyword)
+  "Translate \"BIBLIOGRAPHY\" keywords into HTML syntax.
+Fallback to `html' back-end for other keywords."
+  (let ((keyword (ad-get-arg 0)))
+    (if (not (equal (org-element-property :key keyword) "BIBLIOGRAPHY"))
+        ad-do-it
+      (setq ad-return-value
+            (cdr (assq keyword org-bibtex-html-keywords-alist))))))
+
+(defadvice org-html-latex-fragment (around bibtex-citation)
+  "Translate \"\\cite\" LaTeX fragments into HTML syntax.
+Fallback to `html' back-end for other keywords."
+  (let ((fragment (ad-get-arg 0)))
+    (if (not (org-bibtex-citation-p fragment)) ad-do-it
+      (setq ad-return-value
+            (mapconcat
+             (lambda (key)
+               (let ((key (org-trim key)))
+                 (format "[<a href=\"#%s\">%s</a>]"
+                         key
+                         (or (cdr (assoc key org-bibtex-html-entries-alist))
+                             key))))
+             (org-split-string (org-bibtex-get-citation-key fragment) ",")
+             "")))))
+
+(ad-activate 'org-html-keyword)
+(ad-activate 'org-html-latex-fragment)
+
+
+;;;; Filter
+
+(defun org-bibtex-process-bib-files (tree backend info)
+  "Send each bibliography in parse tree to \"bibtex2html\" process.
+Return new parse tree.  This function assumes current back-end is HTML."
+  ;; Initialize dynamically scoped variables.  The first one
+  ;; contain an alist between keyword objects and their HTML
+  ;; translation.  The second one will contain an alist between
+  ;; citation keys and names in the output (according to style).
+  (setq org-bibtex-html-entries-alist nil
+        org-bibtex-html-keywords-alist nil)
+  (org-element-map tree 'keyword
+    (lambda (keyword)
+      (when (equal (org-element-property :key keyword) "BIBLIOGRAPHY")
+        (let ((arguments (org-bibtex-get-arguments keyword))
+              (file (org-bibtex-get-file keyword))
+              temp-file)
+          ;; limit is set: collect citations throughout the document
+          ;; in TEMP-FILE and pass it to "bibtex2html" as "-citefile"
+          ;; argument.
+          (when (plist-get arguments :limit)
+            (let ((citations
+                   (org-element-map tree 'latex-fragment
+                     (lambda (fragment)
+                       (and (org-bibtex-citation-p fragment)
+                            (org-bibtex-get-citation-key fragment))))))
+              (with-temp-file (setq temp-file (make-temp-file "ox-bibtex"))
+                (insert (mapconcat 'identity citations "\n")))
+              (setq arguments
+                    (plist-put arguments
+                               :options
+                               (append (plist-get arguments :options)
+                                       (list "-citefile" temp-file))))))
+          ;; Call "bibtex2html" on specified file.
+          (unless (eq 0 (apply 'call-process
+                               (append '("bibtex2html" nil nil nil)
+                                       '("-a" "-nodoc" "-noheader" "-nofooter")
+                                       (list "--style"
+                                             (org-bibtex-get-style keyword))
+                                       (plist-get arguments :options)
+                                       (list (concat file ".bib")))))
+            (error "Executing bibtex2html failed"))
+          (and temp-file (delete-file temp-file))
+          ;; Open produced HTML file, wrap references within a block and
+          ;; return it.
+          (with-temp-buffer
+            (insert "<div id=\"bibliography\">\n<h2>References</h2>\n")
+            (insert-file-contents (concat file ".html"))
+            (insert "\n</div>")
+            ;; Update `org-bibtex-html-keywords-alist'.
+            (push (cons keyword (buffer-string))
+                  org-bibtex-html-keywords-alist)
+            ;; Update `org-bibtex-html-entries-alist'.
+            (goto-char (point-min))
+            (while (re-search-forward
+                    "a name=\"\\([-_a-zA-Z0-9:]+\\)\">\\(\\w+\\)" nil t)
+              (push (cons (match-string 1) (match-string 2))
+                    org-bibtex-html-entries-alist)))))))
+  ;; Return parse tree unchanged.
+  tree)
+
+(eval-after-load 'ox
+  '(add-to-list 'org-export-filter-parse-tree-functions
+                'org-bibtex-process-bib-files))
+
+
+
+(provide 'ox-bibtex)
+
+;;; ox-bibtex.el ends here