;; Copyright (c) 1991-2002, The Numerical Algorithms Group Ltd.
;; All rights reserved.
;; Copyright (C) 2007-2012, Gabriel Dos Reis.
;; All rights reserved.
;;
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;; modification, are permitted provided that the following conditions are
;; met:
;;
;;     - Redistributions of source code must retain the above copyright
;;       notice, this list of conditions and the following disclaimer.
;;
;;     - Redistributions in binary form must reproduce the above copyright
;;       notice, this list of conditions and the following disclaimer in
;;       the documentation and/or other materials provided with the
;;       distribution.
;;
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;;       names of its contributors may be used to endorse or promote products
;;       derived from this software without specific prior written permission.
;;
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;; IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
;; TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
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;; NAME:    Pre-Parsing Code
;; PURPOSE: BOOT lines are massaged by preparse to make them easier to parse:
;;        1. Trailing -- comments are removed (this is already done, actually).
;;        2. Comments between { and } are removed.
;;        3. BOOT code is column-sensitive. Code which lines up columnarly is
;;           parenthesized and semicolonized accordingly.  For example,
;;
;;                a
;;                        b
;;                        c
;;                                d
;;                e
;;
;;           becomes
;;
;;                a
;;                        (b;
;;                         c
;;                                d)
;;                e
;;
;;           Note that to do this correctly, we also need to keep track of
;;           parentheses already in the code.
 


(IMPORT-MODULE "parsing")
 
(in-package "BOOT")
 
; Global storage
 
(defparameter $INDEX 0                          "File line number of most recently read line.")
(defparameter |$preparseLastLine| ()            "Most recently read line.")
(defparameter |$preparseReportIfTrue| NIL         "Should we print listings?")
(defparameter $LineList nil                     "Stack of preparsed lines.")
(defparameter |$EchoLineStack| nil                "Stack of lines to list.")
(defparameter $IOIndex 0                        "Number of latest terminal input line.")
 
(DEFPARAMETER TOK NIL)
(DEFPARAMETER DEFINITION_NAME NIL)
(DEFPARAMETER LABLASOC NIL)

(defun Initialize-Preparse (strm)
  (setq $INDEX 0 $LineList nil |$EchoLineStack| nil)
  (setq |$preparseLastLine| (|readLine| strm)))
 
(defvar $skipme)
 
(defun |preparse1| (LineList)
 (PROG (($LINELIST LineList) |$EchoLineStack| NUM A I L PSLOC
        INSTRING PCOUNT COMSYM STRSYM OPARSYM CPARSYM N NCOMSYM
        (SLOC -1) (CONTINUE NIL)  (PARENLEV 0) (NCOMBLOCK ())
        (LINES ()) (LOCS ()) (NUMS ()) functor  )
 READLOOP (DCQ (NUM . A) (|preparseReadLine| LineList))
         (cond ((|atEndOfUnit?| A)
                (|preparseEcho| LineList)
                (COND ((NULL LINES) (RETURN NIL))
                      (NCOMBLOCK
                       (|findCommentBlock| NIL NUMS LOCS NCOMBLOCK NIL)))
                (RETURN (|pairList| (|reverse!| NUMS)
			 (PARSEPILES (|reverse!| LOCS) (|reverse!| LINES))))))
         (cond ((and (NULL LINES) (> (LENGTH A) 0) (EQ (CHAR A 0) #\) ))
                ; this is a command line, don't parse it
                (|preparseEcho| LineList)
                (setq |$preparseLastLine| nil) ;don't reread this line
                (SETQ LINE a)
                (CATCH 'SPAD_READER (|doSystemCommand| (subseq LINE 1)))
                (GO READLOOP)))
         (setq L (LENGTH A))
         (if (EQ L 0) (GO READLOOP))
         (setq PSLOC SLOC)
         (setq I 0 INSTRING () PCOUNT 0)
 STRLOOP (setq STRSYM (OR (position #\" A :start I ) L))
         (setq COMSYM (OR (search "--" A :start2 I ) L))
         (setq NCOMSYM (OR (search "++" A :start2 I ) L))
         (setq OPARSYM (OR (position #\( A :start I ) L))
         (setq CPARSYM (OR (position #\) A :start I ) L))
         (setq N (MIN STRSYM COMSYM NCOMSYM OPARSYM CPARSYM))
         (cond ((= N L) (GO NOCOMS))
               ((|escaped?| A N))
               ((= N STRSYM) (setq INSTRING (NOT INSTRING)))
               (INSTRING)
               ((= N COMSYM) (setq A (subseq A 0 N)) (GO NOCOMS)) ; discard trailing comment
               ((= N NCOMSYM)
                (setq SLOC (|indentationLocation| A))
                (COND
                  ((= SLOC N)
                   (COND ((AND NCOMBLOCK (NOT (= N (CAR NCOMBLOCK))))
                          (|findCommentBlock| NUM NUMS LOCS NCOMBLOCK linelist)
                          (SETQ NCOMBLOCK NIL)))
                   (SETQ NCOMBLOCK (CONS N (CONS A (IFCDR NCOMBLOCK))))
                   (SETQ A ""))
                  ('T (PUSH (STRCONC (|makeString| N #\Space)
                                  (SUBSTRING A N ())) $LINELIST)
                      (SETQ $INDEX (1- $INDEX))
                      (SETQ A (SUBSEQ A 0 N))))
         (GO NOCOMS))
               ((= N OPARSYM) (setq PCOUNT (1+ PCOUNT)))
               ((= N CPARSYM) (setq PCOUNT (1- PCOUNT))))
         (setq I (1+ N))
         (GO STRLOOP)
 NOCOMS  (setq SLOC (|indentationLocation| A))
         (setq A (|trimTrailingBlank| A))
         (cond ((NULL SLOC) (setq SLOC PSLOC) (GO READLOOP)))
         (cond ((EQ (ELT A (|maxIndex| A)) #\_)
                (setq CONTINUE T a (subseq A (|maxIndex| A))))
               ((setq CONTINUE NIL)))
         (if (and (null LINES) (= SLOC 0)) ;;test for skipping constructors
             (if (and |$byConstructors|
                      (null (search "==>" a))
                      (not (member (setq functor (intern
                                    (substring a 0 (STRPOSL ": (=" A 0 NIL))))
                                   |$byConstructors|)))
                 (setq $skipme 't)
               (progn (push functor |$constructorsSeen|) (setq $skipme nil))))
         (when (and LINES (EQL SLOC 0))
             (IF (AND NCOMBLOCK (NOT (ZEROP (CAR NCOMBLOCK))))
               (|findCommentBlock| NUM NUMS LOCS NCOMBLOCK linelist))
             (IF (NOT (|ioTerminal?| in-stream))
                 (setq |$preparseLastLine|
                       (|reverse!| |$EchoLineStack|)))
             (RETURN (|pairList| (|reverse!| NUMS)
                        (PARSEPILES (|reverse!| LOCS) (|reverse!| LINES)))))
         (cond ((> PARENLEV 0) (PUSH NIL LOCS) (setq SLOC PSLOC) (GO REREAD)))
         (COND (NCOMBLOCK
                (|findCommentBlock| NUM NUMS LOCS NCOMBLOCK linelist)
                (setq NCOMBLOCK ())))
         (PUSH SLOC LOCS)
 REREAD  (|preparseEcho| LineList)
         (PUSH A LINES)
         (PUSH NUM NUMS)
         (setq PARENLEV (+ PARENLEV PCOUNT))
         (when (and (|ioTerminal?| in-stream) (not continue))
            (setq |$preparseLastLine| nil)
             (RETURN (|pairList| (|reverse!| NUMS)
                           (PARSEPILES (|reverse!| LOCS) (|reverse!| LINES)))))
 
         (GO READLOOP)))
 
(defun PARSEPRINT (L)
  (if L
      (progn (format t "~&~%       ***       PREPARSE      ***~%~%")
             (dolist (X L) (format t "~5d. ~a~%" (car x) (cdr x)))
             (format t "~%"))))
 
(DEFUN |preparseReadLine1| (X)
    (PROG (LINE IND)
      (SETQ LINE (if $LINELIST
                     (pop $LINELIST)
              (|expandLeadingTabs| (|readLine| in-stream))))
      (setq |$preparseLastLine| LINE)
      (and (stringp line) (incf $INDEX))
      (COND
        ( (NOT (STRINGP LINE))
          (RETURN (LIST $INDEX)) ) )
      (SETQ LINE (|trimTrailingBlank| LINE))
      (PUSH (COPY-SEQ LINE) |$EchoLineStack|)
    ;; next line must evaluate $INDEX before recursive call
      (RETURN
        (CONS
          $INDEX
          (COND
            ( (AND (> (SETQ IND (|maxIndex| LINE)) -1) (char= (ELT LINE IND) #\_))
              (setq |$preparseLastLine|
                    (STRCONC (SUBSTRING LINE 0 IND) (CDR (|preparseReadLine1| X))) ))
            ( 'T
              LINE ) ))) ) )
 
(defun PARSEPILES (LOCS LINES)
  "Add parens and semis to lines to aid parsing."
  (mapl #'add-parens-and-semis-to-line 
	(|append!| LINES '(" ")) 
	(|append!| locs '(nil)))
  LINES)
 
(defun add-parens-and-semis-to-line (slines slocs)
 
  "The line to be worked on is (CAR SLINES).  
   It's indentation is (CAR SLOCS).  
   There is a notion of current indentation. Then:
 
    A. Add open paren to beginning of following line if following 
       line's indentation is greater than current, and add close paren
       to end of last succeeding line with following line's indentation.
    B. Add semicolon to end of line if following line's indentation is
       the same.
    C. If the entire line consists of the single keyword then or else, 
       leave it alone."
 
  (let ((start-column (car slocs)))
    (if (and start-column (> start-column 0))
        (let ((count 0)
	      (i 0))
          (seq
           (mapl #'(lambda (next-lines nlocs)
                     (let ((next-line (car next-lines))
			   (next-column (car nlocs)))
                       (incf i)
                       (if next-column
                           (progn 
			     (setq next-column (abs next-column))
			     (if (< next-column start-column)
				 (exit nil))
			     (cond 
			      ((and (eq next-column start-column)
				    (rplaca nlocs (- (car nlocs)))
				    (not (|infixToken?| next-line)))
			       (setq next-lines (|drop| (1- i) slines))
			       (rplaca next-lines 
				       (|addClose| (car next-lines) #\;))
			       (setq count (1+ count))))))))
                 (cdr slines) (cdr slocs)))
          (if (> count 0)
              (progn 
		(setf (char (car slines) (1- (|firstNonblankCharPosition| (car slines))))
		      #\( )
		(setq slines (|drop| (1- i) slines))
		(rplaca slines (|addClose| (car slines) #\) ))))))))