;;; org-babel-asymptote.el --- org-babel functions for asymptote evaluation

;; Copyright (C) 2009 Eric Schulte

;; Author: Eric Schulte
;; Keywords: literate programming, reproducible research
;; Homepage: http://orgmode.org
;; Version: 0.01

;;; License:

;; 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 3, 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 GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.

;;; Commentary:

;; Org-Babel support for evaluating asymptote source code.
;;
;; This differs from most standard languages in that
;;
;; 1) there is no such thing as a "session" in asymptote
;;
;; 2) we are generally only going to return results of type "file"
;;
;; 3) we are adding the "file" and "cmdline" header arguments, if file
;;    is omitted then the -V option is passed to the asy command for
;;    interactive viewing

;;; Requirements:

;; - The asymptote program :: http://asymptote.sourceforge.net/
;;
;; - asy-mode :: Major mode for editing asymptote files

;;; Code:
(require 'org-babel)

(org-babel-add-interpreter "asymptote")

(add-to-list 'org-babel-tangle-langs '("asymptote" "asymptote"))

(defvar org-babel-default-header-args:asymptote '((:results . "file") (:exports . "results"))
  "Default arguments to use when evaluating a asymptote source block.")

(defun org-babel-expand-body:asymptote (body params &optional processed-params)
  (let ((vars (second (or processed-params
                          (org-babel-process-params params)))))
    (concat (mapconcat 'org-babel-asymptote-var-to-asymptote vars "\n") "\n" body "\n")))

(defun org-babel-execute:asymptote (body params)
  "Execute a block of Asymptote code with org-babel.  This function is
called by `org-babel-execute-src-block'."
  (message "executing Asymptote source code block")
  (let* ((processed-params (org-babel-process-params params))
         (result-params (split-string (or (cdr (assoc :results params)) "")))
         (out-file (cdr (assoc :file params)))
         (format (or (and out-file
                          (string-match ".+\\.\\(.+\\)" out-file)
                          (match-string 1 out-file))
                     "pdf"))
         (cmdline (cdr (assoc :cmdline params)))
         (in-file (make-temp-file "org-babel-asymptote"))
         (cmd (concat "asy "
                      (if out-file
                          (concat "-globalwrite -f " format " -o " out-file)
                        "-V")
                      " " cmdline " " in-file)))
    (with-temp-file in-file (insert (org-babel-expand-body:asymptote body params processed-params)))
    (message cmd) (shell-command cmd)
    out-file))

(defun org-babel-prep-session:asymptote (session params)
  (error "Asymptote does not support sessions"))

(defun org-babel-asymptote-var-to-asymptote (pair)
  "Convert an elisp val into a string of asymptote code specifying a var
of the same value."
  (let ((var (car pair))
        (val (if (symbolp (cdr pair))
                 (symbol-name (cdr pair))
               (cdr pair))))
    (cond
     ((integerp val)
      (format "int %S=%S;" var val))
     ((floatp val)
      (format "real %S=%S;" var val))
     ((stringp val)
      (format "string %S=\"%s\";" var val))
     ((listp val)
      (let* ((dimension-2-p (not (null (cdr val))))
             (dim (if dimension-2-p "[][]" "[]"))
             (type (org-babel-asymptote-define-type val))
             (array (org-babel-asymptote-table-to-array
                     val
                     (if dimension-2-p '(:lstart "{" :lend "}," :llend "}")))))
        (format "%S%s %S=%s;" type dim var array))))))

(defun org-babel-asymptote-table-to-array (table params)
  "Convert values of an elisp table into a string of an asymptote array.
Empty cells are ignored."
  (labels ((atom-to-string (table)
                           (cond
                            ((null table) '())
                            ((not (listp (car table)))
                             (cons (if (and (stringp (car table))
                                            (not (string= (car table) "")))
                                       (format "\"%s\"" (car table))
                                     (format "%s" (car table)))
                                   (atom-to-string (cdr table))))
                            (t
                             (cons (atom-to-string (car table))
                                   (atom-to-string (cdr table))))))
           ;; Remove any empty row
           (fix-empty-lines (table)
                            (delq nil (mapcar (lambda (l) (delq "" l)) table))))
    (orgtbl-to-generic
     (fix-empty-lines (atom-to-string table))
     (org-combine-plists '(:hline nil :sep "," :tstart "{" :tend "}") params))))

(defun org-babel-asymptote-define-type (data)
  "Determine type of DATA. DATA is a list.
Type symbol is returned as 'symbol. The type is usually the type
of the first atom encountered, except for arrays of int where
every cell must be of int type."
  (labels ((anything-but-int (el)
                             (cond
                              ((null el) nil)
                              ((not (listp (car el)))
                               (cond
                                ((floatp (car el)) 'real)
                                ((stringp (car el)) 'string)
                                (t
                                 (anything-but-int (cdr el)))))
                              (t
                               (or (anything-but-int (car el))
                                   (anything-but-int (cdr el)))))))
    (or (anything-but-int data) 'int)))

(provide 'org-babel-asymptote)
;;; org-babel-asymptote.el ends here