;;; ob-lob.el --- Functions Supporting the Library of Babel -*- lexical-binding: t; -*-

;; Copyright (C) 2009-2016 Free Software Foundation, Inc.

;; Authors: Eric Schulte
;;	 Dan Davison
;; Keywords: literate programming, reproducible research
;; Homepage: http://orgmode.org

;; 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/>.

;;; Code:
(require 'cl-lib)
(require 'ob-core)
(require 'ob-table)

(declare-function org-babel-ref-split-args "ob-ref" (arg-string))
(declare-function org-element-at-point "org-element" ())
(declare-function org-element-context "org-element" (&optional element))
(declare-function org-element-property "org-element" (property element))
(declare-function org-element-type "org-element" (element))

(defvar org-babel-library-of-babel nil
  "Library of source-code blocks.
This is an association list.  Populate the library by calling
`org-babel-lob-ingest' on files containing source blocks.")

(defvar org-babel-default-lob-header-args
  '((:cache . "no")
    (:exports . "results")
    (:hlines . "no")
    (:noweb . "no")
    (:results . "replace")
    (:session . "none")
    (:tangle . "no"))
  "Default header arguments to use when exporting Babel calls.")

(defun org-babel-lob-ingest (&optional file)
  "Add all named source blocks defined in FILE to `org-babel-library-of-babel'."
  (interactive "fFile: ")
  (let ((lob-ingest-count 0))
    (org-babel-map-src-blocks file
      (let* ((info (let ((org-babel-default-header-args
			  org-babel-default-lob-header-args))
		     (org-babel-get-src-block-info 'light)))
	     (source-name (nth 4 info)))
	(when source-name
	  (setq source-name (intern source-name)
		org-babel-library-of-babel
		(cons (cons source-name info)
		      (assq-delete-all source-name org-babel-library-of-babel))
		lob-ingest-count (1+ lob-ingest-count)))))
    (message "%d src block%s added to Library of Babel"
	     lob-ingest-count (if (> lob-ingest-count 1) "s" ""))
    lob-ingest-count))

;; Functions for executing lob one-liners.

;;;###autoload
(defun org-babel-lob-execute-maybe ()
  "Execute a Library of Babel source block, if appropriate.
Detect if this is context for a Library Of Babel source block and
if so then run the appropriate source block from the Library."
  (interactive)
  (let ((info (org-babel-lob-get-info)))
    (when info
      (org-babel-execute-src-block nil info)
      t)))

(defun org-babel-lob--src-info (name)
  "Return internal representation for Babel data named NAME.
NAME is a string.  This function looks into the current document
for a Babel call or source block.  If none is found, it looks
after NAME in the Library of Babel.  Eventually, if that also
fails, it returns nil."
  ;; During export, look into the pristine copy of the document being
  ;; exported instead of the current one, which could miss some data.
  (with-current-buffer (or org-babel-exp-reference-buffer (current-buffer))
    (org-with-wide-buffer
     (goto-char (point-min))
     (catch :found
       (let ((case-fold-search t)
	     (regexp (org-babel-named-data-regexp-for-name name)))
	 (while (re-search-forward regexp nil t)
	   (let ((element (org-element-at-point)))
	     (when (equal name (org-element-property :name element))
	       (throw :found
		      (pcase (org-element-type element)
			(`src-block (let ((org-babel-default-header-args
					   org-babel-default-lob-header-args))
				      (org-babel-get-src-block-info t element)))
			(`babel-call (org-babel-lob-get-info element))
			;; Non-executable data found.  Since names are
			;; supposed to be unique throughout a document,
			;; bail out.
			(_ nil))))))
	 ;; No element named NAME in buffer.  Try Library of Babel.
	 (cdr (assoc-string name org-babel-library-of-babel)))))))

;;;###autoload
(defun org-babel-lob-get-info (&optional datum)
  "Return internal representation for Library of Babel function call.
Consider DATUM, when provided, or element at point.  Return nil
when not on an appropriate location.  Otherwise return a list
compatible with `org-babel-get-src-block-info', which see."
  (let* ((context (or datum (org-element-context)))
	 (type (org-element-type context)))
    (when (memq type '(babel-call inline-babel-call))
      (pcase (org-babel-lob--src-info (org-element-property :call context))
	(`(,language ,body ,header ,_ ,_ ,_)
	 (let ((begin (org-element-property (if (eq type 'inline-babel-call)
						:begin
					      :post-affiliated)
					    context)))
	   (list language
		 body
		 (apply #'org-babel-merge-params
			header
			(append
			 (org-with-wide-buffer
			  (goto-char begin)
			  (org-babel-params-from-properties language))
			 (list
			  (org-babel-parse-header-arguments
			   (org-element-property :inside-header context))
			  (let ((args (org-element-property :arguments context)))
			    (and args
				 (mapcar (lambda (ref) (cons :var ref))
					 (org-babel-ref-split-args args))))
			  (org-babel-parse-header-arguments
			   (org-element-property :end-header context)))))
		 nil
		 (org-element-property :name context)
		 begin)))
	(_ nil)))))

(provide 'ob-lob)

;; Local variables:
;; generated-autoload-file: "org-loaddefs.el"
;; End:

;;; ob-lob.el ends here