;;; ob-exp.el --- Exportation of org-babel source blocks

;; Copyright (C) 2009, 2010  Free Software Foundation, Inc.

;; Author: Eric Schulte, Dan Davison
;; Keywords: literate programming, reproducible research
;; Homepage: http://orgmode.org
;; Version: 7.01trans

;; This file is part of GNU Emacs.

;; GNU Emacs 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 3 of the License, or
;; (at your option) any later version.

;; GNU Emacs 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 GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.

;;; Commentary:

;; See the online documentation for more information
;; 
;;   http://orgmode.org/worg/org-contrib/babel/

;;; Code:
(require 'ob)
(require 'org-exp-blocks)
(eval-when-compile
  (require 'cl))

(defvar obe-marker nil)
(defvar org-current-export-file)
(defvar org-babel-lob-one-liner-regexp)
(defvar org-babel-ref-split-regexp)
(declare-function org-babel-lob-get-info "ob-lob" ())
(declare-function org-babel-ref-literal "ob-ref" (ref))

(add-to-list 'org-export-interblocks '(src org-babel-exp-inline-src-blocks))
(add-to-list 'org-export-interblocks '(lob org-babel-exp-lob-one-liners))
(add-hook 'org-export-blocks-postblock-hook 'org-exp-res/src-name-cleanup)

(org-export-blocks-add-block '(src org-babel-exp-src-blocks nil))

(defcustom org-export-babel-evaluate t
  "Switch controlling code evaluation during export.
When set to nil no code will be exported as part of the export
process."
  :group 'org-babel
  :type 'boolean)
(put 'org-export-babel-evaluate 'safe-local-variable (lambda (x) (eq x nil)))

(defvar org-babel-function-def-export-keyword "function"
  "The keyword to substitute for the source name line on export.
When exporting a source block function, this keyword will
appear in the exported version in the place of source name
line. A source block is considered to be a source block function
if the source name is present and is followed by a parenthesized
argument list. The parentheses may be empty or contain
whitespace. An example is the following which generates n random
\(uniform) numbers.

#+source: rand(n)
#+begin_src R
  runif(n)
#+end_src")

(defvar org-babel-function-def-export-indent 4
  "Number of characters to indent a source block on export.
When exporting a source block function, the block contents will
be indented by this many characters. See
`org-babel-function-def-export-name' for the definition of a
source block function.")

(defun org-babel-exp-src-blocks (body &rest headers)
  "Process source block for export.
Depending on the 'export' headers argument in replace the source
code block with...

both ---- display the code and the results

code ---- the default, display the code inside the block but do
          not process

results - just like none only the block is run on export ensuring
          that it's results are present in the org-mode buffer

none ----- do not display either code or results upon export"
  (interactive)
  (message "org-babel-exp processing...")
  (save-excursion
    (goto-char (match-beginning 0))
    (let* ((info (org-babel-get-src-block-info))
	   (params (nth 2 info)))
      ;; bail if we couldn't get any info from the block
      (when info
	;; expand noweb references in the original file
	(setf (nth 1 info)
	      (if (and (cdr (assoc :noweb params))
		       (string= "yes" (cdr (assoc :noweb params))))
		  (org-babel-expand-noweb-references
		   info (get-file-buffer org-current-export-file))
		(nth 1 info))))
      (org-babel-exp-do-export info 'block))))

(defun org-babel-exp-inline-src-blocks (start end)
  "Process inline source blocks between START and END for export.
See `org-babel-exp-src-blocks' for export options, currently the
options and are taken from `org-babel-default-inline-header-args'."
  (interactive)
  (save-excursion
    (goto-char start)
    (while (and (< (point) end)
                (re-search-forward org-babel-inline-src-block-regexp end t))
      (let* ((info (save-match-data (org-babel-parse-inline-src-block-match)))
	     (params (nth 2 info))
	     (replacement
	      (save-match-data
		(if (org-babel-in-example-or-verbatim)
		    (buffer-substring (match-beginning 0) (match-end 0))
		  ;; expand noweb references in the original file
		  (setf (nth 1 info)
			(if (and (cdr (assoc :noweb params))
				 (string= "yes" (cdr (assoc :noweb params))))
			    (org-babel-expand-noweb-references
			     info (get-file-buffer org-current-export-file))
			  (nth 1 info)))
		  (org-babel-exp-do-export info 'inline)))))
	(setq end (+ end (- (length replacement) (length (match-string 1)))))
	(replace-match replacement t t nil 1)))))

(defun org-exp-res/src-name-cleanup ()
  "Clean up #+results and #+srcname lines for export.
This function should only be called after all block processing
has taken place."
  (interactive)
  (save-excursion
    (goto-char (point-min))
    (while (org-re-search-forward-unprotected
	    (concat
	     "\\("org-babel-src-name-regexp"\\|"org-babel-result-regexp"\\)")
	    nil t)
      (delete-region
       (progn (beginning-of-line) (point))
       (progn (end-of-line) (+ 1 (point)))))))

(defun org-babel-in-example-or-verbatim ()
  "Return true if point is in example or verbatim code.
Example and verbatim code include escaped portions of
an org-mode buffer code that should be treated as normal
org-mode text."
  (or (org-in-indented-comment-line) 
      (save-excursion
	(save-match-data
	  (goto-char (point-at-bol))
	  (looking-at "[ \t]*:[ \t]")))
      (org-in-regexps-block-p "^[ \t]*#\\+begin_src" "^[ \t]*#\\+end_src")))

(defun org-babel-exp-lob-one-liners (start end)
  "Process Library of Babel calls between START and END for export.
See `org-babel-exp-src-blocks' for export options. Currently the
options are taken from `org-babel-default-header-args'."
  (interactive)
  (let (replacement)
    (save-excursion
      (goto-char start)
      (while (and (< (point) end)
		  (re-search-forward org-babel-lob-one-liner-regexp nil t))
	(setq replacement
	      (let ((lob-info (org-babel-lob-get-info)))
		(save-match-data
		  (org-babel-exp-do-export
		   (list "emacs-lisp" "results"
			 (org-babel-merge-params
			  org-babel-default-header-args
			  (org-babel-parse-header-arguments
			   (org-babel-clean-text-properties
			    (concat ":var results="
				    (mapconcat #'identity
					       (butlast lob-info) " ")))))
			 (car (last lob-info)))
		   'lob))))
	(setq end (+ end (- (length replacement) (length (match-string 0)))))
	(replace-match replacement t t)))))

(defun org-babel-exp-do-export (info type)
  "Return a string with the exported content of a code block.
The function respects the value of the :exports header argument."
  (flet ((silently () (let ((session (cdr (assoc :session (nth 2 info)))))
			(when (and session
				   (not (equal "none" session))
				   (not (assoc :noeval (nth 2 info))))
			  (org-babel-exp-results info type 'silent))))
	 (clean () (org-babel-remove-result info)))
    (case (intern (or (cdr (assoc :exports (nth 2 info))) "code"))
      ('none (silently) (clean) "")
      ('code (silently) (clean) (org-babel-exp-code info type))
      ('results (org-babel-exp-results info type))
      ('both (concat (org-babel-exp-code info type)
		     "\n\n"
		     (org-babel-exp-results info type))))))

(defvar backend)

(defvar org-babel-format-code-functions
  '(inline org-babel-format-code-inline
    block org-babel-format-code-block
    lob org-babel-format-code-lob))

(defun org-babel-format-code-inline (lang body args switches name) 
  (format "=%s=" body))

(defvar org-babel-format-code-block-control-string "%s(%s)")

(defun org-babel-format-code-block-default-style (info)
  (destructuring-bind (lang body args0 switches name &rest ignore) info
    (format org-babel-format-code-block-control-string
	    name
	    (mapconcat #'identity args ", "))))

(defun org-babel-format-code-block-alternate-style (info)
  (destructuring-bind (lang body args0 switches name &rest ignore) info
    (format "SOURCE: %s ARGUMENTS: %s LANGUAGE: %s"
	    name (if (null args) "None."
		     (mapconcat #'identity args ", "))
	    lang)))

(defvar org-babel-format-code-block-caption-function
  'org-babel-format-code-block-default-style) 

(defun org-babel-format-code-block (lang body args switches name) 
  (let ((str
	 (format "#+BEGIN_SRC %s %s\n%s%s#+END_SRC\n" lang switches body
		 (if (and body (string-match "\n$" body))
		     "" "\n"))))
    (when name
      (add-text-properties
       0 (length str)
       (list 'org-caption
	     (funcall org-babel-format-code-block-caption-function 
		      (list lang body args switches name)))
       str))
    str))

(defun org-babel-format-code-lob (lang body args switches name) 
  (let ((call-line (and (string-match "results=" (car args))
			(substring (car args) (match-end 0)))))
    (cond
      ((eq backend 'html)
       (format "\n#+HTML: <label class=\"org-src-name\">%s</label>\n"
	       call-line))
      ((format ": %s\n" call-line)))))

(defun org-babel-exp-code (info type)
  "Prepare and return code in the current code block for export.
Code is prepared in a manner suitable for export by
org-mode.  This function is called by `org-babel-exp-do-export'.
The code block is not evaluated."
  (destructuring-bind (lang body args0 switches name &rest ignore) info
    (let ((args (mapcar #'cdr
			(org-remove-if-not (lambda (el) (eq :var (car el))) args0))))
      (let ((formatter (getf org-babel-format-code-functions type)))
	(funcall formatter lang body args switches name)))))

(defun org-babel-exp-results (info type &optional silent)
  "Evaluate and return the results of the current code block for export.
Results are prepared in a manner suitable for export by org-mode.
This function is called by `org-babel-exp-do-export'.  The code
block will be evaluated.  Optional argument SILENT can be used to
inhibit insertion of results into the buffer."
  (if org-export-babel-evaluate
      (let ((lang (nth 0 info))
	    (body (nth 1 info))
	    (params
	     ;; lets ensure that we lookup references in the original file
	     (mapcar
	      (lambda (pair)
		(if (and org-current-export-file
			 (eq (car pair) :var)
			 (string-match org-babel-ref-split-regexp (cdr pair))
			 (equal :ob-must-be-reference
				(org-babel-ref-literal
				 (match-string 2 (cdr pair)))))
		    `(:var . ,(concat (match-string 1 (cdr pair))
				      "=" org-current-export-file
				      ":" (match-string 2 (cdr pair))))
		  pair))
	      (nth 2 info))))
	;; skip code blocks which we can't evaluate
	(if (fboundp (intern (concat "org-babel-execute:" lang)))
	    (case type
	      ('inline
		(let ((raw (org-babel-execute-src-block
			    nil info '((:results . "silent"))))
		      (result-params (split-string
				      (cdr (assoc :results params)))))
		  (unless silent
		    (cond ;; respect the value of the :results header argument
		     ((member "file" result-params)
		      (org-babel-result-to-file raw))
		     ((or (member "raw" result-params)
			  (member "org" result-params))
		      (format "%s" raw))
		     ((member "code" result-params)
		      (format "src_%s{%s}" lang raw))
		     (t
		      (if (stringp raw)
			  (if (= 0 (length raw)) "=(no results)="
			    (format "%s" raw))
			(format "%S" raw)))))))
	      ('block
		  (org-babel-execute-src-block
		   nil info (org-babel-merge-params
			     params
			     `((:results . ,(if silent "silent" "replace")))))
		"")
	      ('lob
	       (save-excursion
		 (re-search-backward org-babel-lob-one-liner-regexp nil t)
		 (org-babel-execute-src-block
		  nil info (org-babel-merge-params
			    params
			    `((:results . ,(if silent "silent" "replace")))))
		 "")))
	  ""))
    ""))

(provide 'ob-exp)

;; arch-tag: 523abf4c-76d1-44ed-9f27-e3bddf34bf0f

;;; ob-exp.el ends here