;; -*-  Mode: Lisp; Package: Maxima; Syntax: Common-Lisp; Base: 10 -*- ;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;                                                                    ;;;;;
;;;  Copyright (c) 1984,1987 by William Schelter,University of Texas   ;;;;;
;;;     All rights reserved                                            ;;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(in-package :maxima)

(defmacro defun-prop (f arg &body body)
  (assert (listp f))
  #+gcl (eval-when (eval) (compiler::compiler-def-hook (first f) body))
  `(setf (get ',(first f) ',(second f)) #'(lambda ,arg ,@body)))

(defvar *prin1* nil)		  ;a function called instead of prin1.

;; Should we give this a different name?
(defvar *fortran-print* nil
  "Tells EXPLODEN we are printing numbers for Fortran so include the exponent marker.")

(defun appears (tree var)
  (cond ((equal tree var)
	 (throw 'appears t))
	((atom tree) nil)
	(t  (appears  (car tree) var)
	    (appears (cdr tree)  var)))
  nil)

(defun appears1 (tree var)
  (cond ((eq tree var)
	 (throw 'appears t))
	((atom tree) nil)
	(t
	 (appears (car tree) var)
	 (appears (cdr tree) var)))
  nil)

(defun appears-in (tree var)
  "Yields t if var appears in tree"
  (catch 'appears
    (if (or (symbolp var) (fixnump var))
	(appears1 tree var)
	(appears tree var))))

;; A more portable implementation of ml-typep.  I (rtoy) think it
;; would probably be better to replace uses of
;; ml-typep with the corresponding Common Lisp typep or type-of or
;; subtypep, as appropriate.
(defun ml-typep (x &optional type)
  (cond (type
	 (cl:let ((pred (get type 'ml-typep)))
	   (if pred
	       (funcall pred x)
	       (typep x type))))
	(t
	 (typecase x
	   (cl:cons 'list)
	   (cl:fixnum 'fixnum)
	   (cl:integer 'bignum)
	   (cl:float 'flonum)
	   (cl:number 'number)
	   (cl:array 'array)
	   (cl:hash-table 'hash-table)
	   (t
	    (type-of x))))))

(defprop :extended-number extended-number-p ml-typep)
(defprop array arrayp ml-typep)
(defprop atom  atom ml-typep)

#+(or cmu scl)
(eval-when (:compile-toplevel :load-toplevel :execute)
  (shadow '(cl:compiled-function-p) (find-package :maxima))
)
#+(or cmu scl)
(defun compiled-function-p (x)
  (and (functionp x) (not (symbolp x))
       (not (eval:interpreted-function-p x))))

(defprop compiled-function compiled-function-p ml-typep)
(defprop extended-number extended-number-p ml-typep)
(defprop fixnum fixnump ml-typep)
(defprop list consp ml-typep)
(defprop number numberp ml-typep)
(defprop string stringp ml-typep)
(defprop symbol  symbolp ml-typep)


(defvar *maxima-arrays* nil
  "Trying to track down any functional arrays in maxima")

;;only remaining calls are for maclisp-type = nil
(defun *array (name maclisp-type &rest dimlist &aux aarray)
  (cond ((member maclisp-type '(readtable obarray) :test #'eq)
	 (error " bad type ~S" maclisp-type)))
  (pushnew name *maxima-arrays*)	;for tracking down old ones.
  (setq aarray (make-array dimlist :initial-element (case maclisp-type
						      (fixnum 0)
						      (flonum 0.0)
						      (otherwise nil))))
  (cond ((null name) aarray)
	((symbolp name)
	 (setf (symbol-array name) aarray)
	 name)
	(t (error "~S is illegal first arg for *array" name))))

;;;    Change maclisp array referencing.
;;;   Idea1: Make changes in the code which will allow the code to still run in maclisp,
;;;yet will allow, with the appropriate macro definitions of array,arraycall, etc,
;;;to put the array into the value-cell.
;;;   Idea2: Make changes in the array referencing of (a dim1 dim2..) to (arraycall nil (symbol-array a) dim1..)
;;;which would then allow expansion into something which is common lisp compatible, for
;;;the day when (a 2 3) no longer is equivalent to (aref (symbol-function a) 2 3).
;;;I.  change (array a typ dim1 dim2..) to expand to (defvar a (make-array (list dim1 dim2 ...) :type typ')
;;;II. change (a dim1 dim2..) to (arraycall nil (symbol-array a) dim1 dim2 ..)
;;;III define
;;(defmacro symbol-array (ar)
;;    `(symbol-function ,ar))
;;(defmacro arraycall (ignore ar &rest dims)
;;  `(aref ,ar ,@ dims))
;;;IV. change array setting to use (setf (arraycall nil ar dim1.. ) val)
;;;which will generate the correct setting code on the lispm and will
;;;still work in maclisp.

(defmacro maxima-error (datum &rest args)
  `(cerror "without any special action" ,datum ,@args))

(defmacro safe-value (sym)
  (cond ((symbolp sym)
	 `(cond ((symbolp ',sym)
		 (and (boundp ',sym) ,sym))
	   (t ,sym)))
	(t nil)))

(defmacro show (&rest l)
  (loop for v in l
	 collecting `(format t "~%The value of ~A is ~A" ',v ,v) into tem
	 finally (return `(progn ,@ tem))))

(defmacro defquote  (fn (aa . oth) &body rest &aux help ans)
  (setq help (intern (format nil "~a-~a" fn '#:aux)))
  (cond ((eq aa '&rest)
	 (setq ans
	       (list
		`(defmacro ,fn (&rest ,(car oth))
		  `(,',help  ',,(car oth)))
		`(defun ,help (,(car oth)) ,@rest))))
	(t (when (member '&rest oth)
	     (error "at present &rest may only occur as first item in a defquote argument"))
	   (setq ans
		 (list
		  `(defmacro ,fn (,aa . other)
		    (setq other (loop for v in other collecting (list 'quote v)))
		    (check-arg other (eql (length other) ,(length oth))
			       ,(format nil "wrong number of args to ~a" fn))
		    `(,',help ',,aa ,@ other))
		  `(defun ,help (,aa ,@ oth) ,@rest)))))
  `(progn ,@ans))


;;the resulting function will translate to defvar and will behave
;;correctly for the evaluator.

;;(defun gg fexpr (ll)
;;       body)
;;(defquote gg (&rest ll)
;;       body)

;;(DEFQUOTE GG ( &rest C)
;; (list  (car c) (second c) ))
;;the big advantage of using the following over defmspec is that it
;;seems to translate more easily, since it is a fn.
;;New functions which wanted quoted arguments should be defined using
;;defquote


(defun onep (x) (eql 1 x))

(defun extended-number-p (x)
  (member (type-of x) '(bignum rational float )))

(defvar *scan-string-buffer*  nil)

(defun macsyma-read-string (a-string &aux answer)
  (cond ((not (or (search "$" a-string :test #'char-equal)
		  (search ";" a-string :test #'char-equal)))
	 (vector-push-extend #\$ a-string)))
  (with-input-from-string (stream a-string)
    (setq answer (third (mread stream)))
    answer))

(defvar *sharp-read-buffer*
  (make-array 140 :element-type ' #.(array-element-type "a") :fill-pointer 0 :adjustable t))

(defun x$-cl-macro-read (stream sub-char arg)
  (declare (ignore arg))
  ($-read-aux sub-char stream))

(defun $-read-aux (arg stream &aux (meval-flag t) (*mread-prompt* ""))
  (declare (special *mread-prompt*)
	   (ignore arg))
  (setf (fill-pointer *sharp-read-buffer*) 0)
  (cond ((eql #\$ (peek-char t stream))
	 (tyi stream)
	 (setq meval-flag nil)))
  (with-output-to-string (st *sharp-read-buffer*)
    (let (char)
      (loop while (not (eql char #\$))
	     do
	     (setq char (tyi stream))
	     (write-char char st))))
  (if meval-flag
      (list 'meval* (list 'quote (macsyma-read-string *sharp-read-buffer*)))
      (list 'quote (macsyma-read-string *sharp-read-buffer*))))

(set-dispatch-macro-character #\# #\$ #'x$-cl-macro-read)

(defvar *macsyma-readtable*)

(defun find-lisp-readtable-for-macsyma ()
  (cond ((and (boundp '*macsyma-readtable*)
	      (readtablep *macsyma-readtable*))
	 *macsyma-readtable*)
	(t (setq *macsyma-readtable* (copy-readtable nil))
	   (set-dispatch-macro-character #\# #\$ 'x$-cl-macro-read *macsyma-readtable*)
	   *macsyma-readtable*)))

(defun set-readtable-for-macsyma ()
  (setq *readtable* (find-lisp-readtable-for-macsyma)))

(defvar *reset-var* t)

(defvar *variable-initial-values* (make-hash-table)
  "Hash table containing all Maxima defmvar variables and their initial
values")

(defmacro defmvar (var &rest val-and-doc)
  "If *reset-var* is true then loading or eval'ing will reset value, otherwise like defvar"
  (cond ((> (length val-and-doc) 2)
	 (setq val-and-doc (list (car val-and-doc) (second val-and-doc)))))
  `(progn
    (unless (gethash ',var *variable-initial-values*)
      (setf (gethash ',var *variable-initial-values*)
	    ,(first val-and-doc)))
    (defvar ,var ,@val-and-doc)))

(defun $mkey (variable)
  "($mkey '$demo)==>:demo"
  (intern (string-left-trim "$" (string variable)) 'keyword))

(defmacro arg (x)
  `(narg1 ,x narg-rest-argument))

(defun narg1 (x l &aux tem)
  (cond ((null x) (length l))
	(t (setq tem (nthcdr (1- x) l))
	   (cond ((null tem) (error "arg ~A beyond range ~A " x (length l)))
		 (t (car tem))))))

(defmacro listify (x)
  `(listify1 ,x narg-rest-argument))

(defmacro setarg (i val)
  `(setarg1 ,i ,val narg-rest-argument))

(defun setarg1 (i val l)
  (setf (nth (1- i) l) val)
  val)

(defun listify1 (n narg-rest-argument)
  (cond ((minusp n) (copy-list (last narg-rest-argument (- n))) )
	((zerop n) nil)
	(t (subseq narg-rest-argument 0 n))))

(defmacro defmfun (function &body  rest &aux .n.)
  (cond ((and (car rest) (symbolp (car rest)))
	 ;;old maclisp narg syntax
	 (setq .n. (car rest))
	 (setf (car rest)
	       `(&rest narg-rest-argument &aux (, .n. (length narg-rest-argument))))))
  `(progn
    ;; I (rtoy) think we can consider all defmfun's as translated functions.
    (defprop ,function t translated)
    (defun ,function . ,rest)))

;;sample usage
;;(defmfun foo a (show a )(show (listify a)) (show (arg 3)))

(defun exploden (symb)
  (let* (#+(and gcl (not gmp)) (big-chunk-size 120)
	   #+(and gcl (not gmp)) (tentochunksize (expt 10 big-chunk-size))
	   string)
    (cond ((symbolp symb)
	   (setq string (print-invert-case symb)))
	  ((floatp symb)
	   (setq string (exploden-format-float symb)))

      ((integerp symb)
       ;; When obase > 10, prepend leading zero to
       ;; ensure that output is readable as a number.
       (let ((leading-digit (if (> *print-base* 10) #\0)))
         (cond
           #+(and gcl (not gmp))
           ((bignump symb)
            (let* ((big symb)
                   ans rem tem
                   (chunks
                     (loop
                       do (multiple-value-setq (big rem)
                            (floor big tentochunksize))
                       collect rem
                       while (not (eql 0 big)))))
              (setq chunks (nreverse chunks))
              (setq ans (coerce (format nil "~d" (car chunks)) 'list))
              (if (and leading-digit (not (digit-char-p (car ans) 10.)))
                (setq ans (cons leading-digit ans)))
              (loop for v in (cdr chunks)
                    do (setq tem (coerce (format nil "~d" v) 'list))
                    (loop for i below (- big-chunk-size (length tem))
                          do (setq tem (cons #\0 tem)))
                    (setq ans (nconc ans tem)))
              (return-from exploden ans)))
           (t
             (setq string (format nil "~A" symb))
             (setq string (coerce string 'list))
             (if (and leading-digit (not (digit-char-p (car string) 10.)))
               (setq string (cons leading-digit string)))
             (return-from exploden string)))))

	  (t (setq string (format nil "~A" symb))))
    (assert (stringp string))
    (coerce string 'list)))

(defvar *exploden-strip-float-zeros* t) ;; NIL => allow trailing zeros

(defun exploden-format-float (symb)
  (declare (special $maxfpprintprec))
  (let ((a (abs symb))
        string
        (effective-printprec (if (or (= $fpprintprec 0)
                                     (> $fpprintprec $maxfpprintprec))
                                 $maxfpprintprec
                                 $fpprintprec)))
    ;; When printing out something for Fortran, we want to be
    ;; sure to print the exponent marker so that Fortran
    ;; knows what kind of number it is.  It turns out that
    ;; Fortran's exponent markers are the same as Lisp's so
    ;; we just need to make sure the exponent marker is
    ;; printed.
    (if *fortran-print*
        (setq string (format nil "~e" symb))
        (multiple-value-bind (form digits)
          (cond
            ((zerop a)
             (values "~,vf" 1))
            ((<= 0.001 a 1e7)
             (let*
               ((integer-log10 (floor (/ (log a) #.(log 10.0))))
                (scale (1+ integer-log10)))
               (if (< scale effective-printprec)
                 (values "~,vf" (- effective-printprec scale))
                 (values "~,ve" (1- effective-printprec)))))
            (t
              (values "~,ve" (1- effective-printprec))))

          ;; Call FORMAT using format string chosen above.
          (setq string (format nil form digits a))

          ;; EXPLODEN is often called after NFORMAT, so it doesn't
          ;; usually see a negative argument. I can't guarantee
          ;; a non-negative argument, so handle negative here.
          (if (< symb 0)
            (setq string (concatenate 'string "-" string)))))

    (if *exploden-strip-float-zeros*
      (or (strip-float-zeros string) string)
      string)))

(defun trailing-zeros-regex-f-0 (s) (funcall #.(maxima-nregex::regex-compile "^(.*\\.[0-9]*[1-9])00*$") s))
(defun trailing-zeros-regex-f-1 (s) (funcall #.(maxima-nregex::regex-compile "^(.*\\.0)00*$") s))
(defun trailing-zeros-regex-e-0 (s) (funcall #.(maxima-nregex::regex-compile "^(.*\\.[0-9]*[1-9])00*([^0-9][+-][0-9]*)$") s))
(defun trailing-zeros-regex-e-1 (s) (funcall #.(maxima-nregex::regex-compile "^(.*\\.0)00*([^0-9][+-][0-9]*)$") s))

;; Return S with trailing zero digits stripped off, or NIL if there are none.

(defun strip-float-zeros (s)
  (cond
    ((or (trailing-zeros-regex-f-0 s) (trailing-zeros-regex-f-1 s))
     (let
       ((group1 (aref maxima-nregex::*regex-groups* 1)))
       (subseq s (first group1) (second group1))))
    ((or (trailing-zeros-regex-e-0 s) (trailing-zeros-regex-e-1 s))
     (let*
       ((group1 (aref maxima-nregex::*regex-groups* 1))
        (s1 (subseq s (first group1) (second group1)))
        (group2 (aref maxima-nregex::*regex-groups* 2))
        (s2 (subseq s (first group2) (second group2))))
       (concatenate 'string s1 s2)))
    (t nil)))

(defun explodec (symb)		;is called for symbols and numbers
  (loop for v in (coerce (print-invert-case symb) 'list)
     collect (intern (string v))))

(defvar *string-for-implode*
  (make-array 20 :fill-pointer 0 :adjustable t :element-type '#.(array-element-type "a")))

;;; If the 'string is all the same case, invert the case.  Otherwise,
;;; do nothing.
#-(or scl allegro)
(defun maybe-invert-string-case (string)
  (let ((all-upper t)
	(all-lower t)
	(length (length string)))
    (dotimes (i length)
      (let ((ch (char string i)))
	(when (both-case-p ch)
	  (if (upper-case-p ch)
	      (setq all-lower nil)
	      (setq all-upper nil)))))
    (cond (all-upper
	   (string-downcase string))
	  (all-lower
	   (string-upcase string))
	  (t
	   string))))

#+(or scl allegro)
(defun maybe-invert-string-case (string)
  (cond (#+scl (eq ext:*case-mode* :lower)
	 #+allegro (eq excl:*current-case-mode* :case-sensitive-lower)
	 string)
	(t
	 (let ((all-upper t)
	       (all-lower t)
	       (length (length string)))
	   (dotimes (i length)
	     (let ((ch (aref string i)))
	       (when (both-case-p ch)
		 (if (upper-case-p ch)
		     (setq all-lower nil)
		     (setq all-upper nil)))))
	   (cond (all-upper
		  (string-downcase string))
		 (all-lower
		  (string-upcase string))
		 (t
		  string))))))

(defun intern-invert-case (string)
  ;; Like read-from-string with readtable-case :invert
  ;; Supply package argument in case this function is called
  ;; from outside the :maxima package.
  (intern (maybe-invert-string-case string) :maxima))


#-(or gcl scl allegro)
(let ((local-table (copy-readtable nil)))
  (setf (readtable-case local-table) :invert)
  (defun print-invert-case (sym)
    (let ((*readtable* local-table)
	  (*print-case* :upcase))
      (princ-to-string sym))))

#+(or scl allegro)
(let ((local-table (copy-readtable nil)))
  (unless #+scl (eq ext:*case-mode* :lower)
	  #+allegro (eq excl:*current-case-mode* :case-sensitive-lower)
    (setf (readtable-case local-table) :invert))
  (defun print-invert-case (sym)
    (cond (#+scl (eq ext:*case-mode* :lower)
	   #+allegro (eq excl:*current-case-mode* :case-sensitive-lower)
	   (let ((*readtable* local-table)
		 (*print-case* :downcase))
	     (princ-to-string sym)))
	  (t
	   (let ((*readtable* local-table)
		 (*print-case* :upcase))
	     (princ-to-string sym))))))

#+gcl
(defun print-invert-case (sym)
  (cond ((symbolp sym)
	 (let* ((str (princ-to-string sym))
		(have-upper nil)
		(have-lower nil)
		(converted-str
		 (map 'string (lambda (c)
				(cond ((upper-case-p c)
				       (setf have-upper t)
				       (char-downcase c))
				      ((lower-case-p c)
				       (setf have-lower t)
				       (char-upcase c))
				      (t c)))
		      str)))
	   (if (and have-upper have-lower)
	       str
	       converted-str)))
	(t (princ-to-string sym))))

(defun implode (lis)
  (let ((ar *string-for-implode*)
	(leng (length lis)))
    (unless (> (array-total-size ar) leng)
      (setq ar (adjust-array ar (+ leng 20))))
    (setf (fill-pointer ar) leng)
    (loop for v in lis
       for i below leng
       do
	 (setf (aref ar i) (cond ((characterp v) v)
				 ((symbolp v) (char (symbol-name v) 0))
				 ((numberp v) (code-char v)))))
    (intern-invert-case ar)))

;; Note:  symb can also be a number, not just a symbol.
(defun explode (symb)
  (loop for v in (coerce (format nil "~S" symb) 'list)
     collect (intern (string v))))

(defun getcharn (symb i)
  (let ((strin (string symb)))
    (if (<= 1 i (length strin))
	(char strin (1- i))
    nil)))

(defun getchar (symb i)
  (let ((str (string symb)))
    (if (<= 1 i (length str))
	(intern (string (char str (1- i))))
	nil)))

(defun ascii (n)
  (intern (string n)))

(defun maknam (lis)
  (loop for v in lis
     when (symbolp v)
     collecting (char (symbol-name v) 0) into tem
     else
     when (characterp v)
     collecting v into tem
     else do (maxima-error "bad entry")
     finally
     (return (make-symbol (maybe-invert-string-case (coerce tem 'string))))))

;;for those window labels etc. that are wrong type.
;; is not only called for symbols, but also on numbers
(defun flatc (sym)
  (length (explodec sym)))

(defun flatsize (sym &aux (*print-circle* t))
  (length (exploden sym)))

(defmacro safe-zerop (x)
  (cond((symbolp x)
	`(and (numberp ,x) (zerop ,x)))
       (t `(let ((.x. ,x))
	    (and (numberp .x.) (zerop .x.))))))

(defmacro signp (sym x)
  (cond ((atom x)
	 (let ((test
		(case sym
		  (e `(zerop ,x))
		  (l `(< ,x 0))
		  (le `(<= ,x 0))
		  (g `(> ,x 0))
		  (ge `(>= ,x 0))
		  (n `(not (zerop ,x))))))
	   `(and (numberp ,x) ,test)))
	(t `(let ((.x. ,x))
	     (signp ,sym .x.)))))

(defvar *prompt-on-read-hang* nil)
(defvar *read-hang-prompt* "")

(defun tyi-raw (&optional (stream *standard-input*) eof-option)
  ;; Adding this extra EOF test, because the testsuite generates
  ;; unexpected end of input-stream with Windows XP and GCL 2.6.8.
  #+gcl
  (when (eq (peek-char nil stream nil eof-option) eof-option)
    (return-from tyi-raw eof-option))

  (let ((ch (read-char-no-hang stream nil eof-option)))
    (if ch
	ch
	(progn
	  (when (and *prompt-on-read-hang* *read-hang-prompt*)
	    (princ *read-hang-prompt*)
	    (force-output *standard-output*))
	  (read-char stream nil eof-option)))))

(defun tyi (&optional (stream *standard-input*) eof-option)
  (let ((ch (tyi-raw stream eof-option)))
    (if (eq ch eof-option)
      ch
      (backslash-check ch stream eof-option))))

; The sequences of characters
; <anything-except-backslash>
;   (<backslash> <newline> | <backslash> <return> | <backslash> <return> <newline>)+
;   <anything>
; are reduced to <anything-except-backslash> <anything> .
; Note that this has no effect on <backslash> <anything-but-newline-or-return> .

(let ((previous-tyi #\a))
  (defun backslash-check (ch stream eof-option)
    (if (eq previous-tyi #\\ )
      (progn (setq previous-tyi #\a) ch)
      (setq previous-tyi
	(if (eq ch #\\ )
	  (let ((next-char (peek-char nil stream nil eof-option)))
	    (if (or (eq next-char #\newline) (eq next-char #\return))
	      (eat-continuations ch stream eof-option)
	      ch))
	  ch))))
  ; We have just read <backslash> and we know the next character is <newline> or <return>.
  ; Eat line continuations until we come to something which doesn't match, or we reach eof.
  (defun eat-continuations (ch stream eof-option)
    (setq ch (tyi-raw stream eof-option))
    (do () ((not (or (eq ch #\newline) (eq ch #\return))))
      (let ((next-char (peek-char nil stream nil eof-option)))
	(if (and (eq ch #\return) (eq next-char #\newline))
	  (tyi-raw stream eof-option)))
      (setq ch (tyi-raw stream eof-option))
      (let ((next-char (peek-char nil stream nil eof-option)))
	(if (and (eq ch #\\ ) (or (eq next-char #\return) (eq next-char #\newline)))
	  (setq ch (tyi-raw stream eof-option))
	  (return-from eat-continuations ch))))
    ch))

(defvar ^w nil)

(defun $timedate (&optional (time (get-universal-time)))
  (let*
    ((time-integer (mfuncall '$floor time))
     (time-fraction (sub time time-integer))
     (time-millis (mfuncall '$round (mul 1000 time-fraction))))
    (when (= time-millis 1000)
      (setq time-integer (1+ time-integer))
      (setq time-millis 0))
    (multiple-value-bind
      (second minute hour date month year day-of-week dst-p tz)
      (decode-universal-time time-integer)
      (declare (ignore day-of-week))
      (let
        ((tz-offset (if dst-p (- 1 tz) (- tz))))
        (multiple-value-bind
          (tz-hours tz-hour-fraction)
          (floor tz-offset)
          (let
            ((tz-sign (if (< 0 tz-hours) #\+ #\-)))
            (if (= time-millis 0)
              (format nil "~4,'0d-~2,'0d-~2,'0d ~2,'0d:~2,'0d:~2,'0d~a~2,'0d:~2,'0d"
                  year month date hour minute second tz-sign (abs tz-hours) (floor (* 60 tz-hour-fraction)))
              (format nil "~4,'0d-~2,'0d-~2,'0d ~2,'0d:~2,'0d:~2,'0d.~3,'0d~a~2,'0d:~2,'0d"
                  year month date hour minute second time-millis tz-sign (abs tz-hours) (floor (* 60 tz-hour-fraction))))))))))

;; Parse date/time strings in these formats (and only these):
;;
;;   YYYY-MM-DD[ T]hh:mm:ss[,.]nnn
;;   YYYY-MM-DD[ T]hh:mm:ss
;;   YYYY-MM-DD

(defun date-match-date (s) (funcall #.(maxima-nregex::regex-compile "([0-9][0-9][0-9][0-9])-([0-9][0-9])-([0-9][0-9])") s))
(defun date-match-date+time (s) (funcall #.(maxima-nregex::regex-compile "([0-9][0-9][0-9][0-9])-([0-9][0-9])-([0-9][0-9])[ T]([0-9][0-9]):([0-9][0-9]):([0-9][0-9])") s))
(defun date-match-date+time+ms (s) (funcall #.(maxima-nregex::regex-compile "([0-9][0-9][0-9][0-9])-([0-9][0-9])-([0-9][0-9])[ T]([0-9][0-9]):([0-9][0-9]):([0-9][0-9])[,.]([0-9][0-9][0-9])") s))

(defun $parse_timedate (s)
  (if (date-match-date+time+ms s)
    (date-parse-foo s)
    (if (date-match-date+time s)
      (date-parse-foo s)
      (if (date-match-date s)
        (date-parse-foo s)))))

(defun date-parse-foo (s)
  (let ((groups maxima-nregex::*regex-groups*) (ngroups maxima-nregex::*regex-groupings*))
    (apply #'construct-universal-time
      (mapcar #'parse-integer
        (extract-date-bits s (rest (coerce (subseq groups 0 ngroups) 'list)))))))

(defun extract-date-bits (s groups)
  (loop for p in groups while p collect (apply #'subseq (cons s p))))

(defun construct-universal-time (year month day &optional (hour 0) (minute 0) (second 0) (ms 0))
  (add (div ms 1000) (encode-universal-time second minute hour day month year)))

;;Some systems make everything functionp including macros:
(defun functionp (x)
  (cond ((symbolp x)
	 (and (not (macro-function x))
	      (fboundp x) t))
	 ((cl:functionp x))))

;; These symbols are shadowed because we use them also as special
;; variables.
(deff break #'cl:break)
(deff gcd #'cl:gcd)

#+(and sbcl sb-package-locks)
(defun makunbound (sym)
  (sb-ext:without-package-locks
      (cl:makunbound sym)))
