; The GIMP -- an image manipulation program
; Copyright (C) 1995 Spencer Kimball and Peter Mattis
; 
; read/write a parasite script  for GIMP 1.2
; Copyright (C) 2001-2002 Iccii <iccii@hotmail.com>
; 
; --------------------------------------------------------------------
; 
; First, I'll recommend you to use Parasite Editor written in Perl-Fu
; if you don't have Perl environment e.g. Windows Gimp user.
; 
; 1) List up the current parasite name with No. in target object
;    (Image or Drawable or Global). Check parasite number.
; 
; 2) Read the parasite contents by entering parasite number. Then,
;    you'll get current parasite informatin.
; 
; 3) If you add new parasite, select "Create new" and enter new name.
;    then, you'll have new parasite with no contents.
; 
; 4) If you edit parasite contens, select "Overwrite" and select
;    target parasite number and enter new contents (string).
; 
; 5) Select "Remove" and select target parasite number if you want to
;    remove parasite from parasite list
;
; For example, Image has "Created with The GIMP" in "gimp-comment"
; when you create new blank image.
;	(No.)	(name)		(contents)
;	0	gimp-comment	Created with The GIMP
;
; --------------------------------------------------------------------
; version 0.0  by Iccii 2001/08/10
;     - Initial relase (not work yet!)
; version 0.1  by Iccii 2001/08/26
;     - Now, real initial relase
;     - Script can show current parasite list
; version 0.2  by Iccii 2001/08/27
;     - Add Overwrite option
; version 0.3  by Iccii 2001/08/28
;     - Add Read option
;     - Add helper function
; version 0.4  by Iccii 2001/08/29
;     - Add remove option
; version 0.5  by Iccii 2001/09/25
;     - Add Create new option
;     - Bug fixed in reading a parasite
; version 0.6  by Iccii 2001/09/27
;     - Add Addtional write option
; version 0.7  by Iccii 2002/01/05
;     - Added Export to File option
;
; --------------------------------------------------------------------
; 
; 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 2 of the License, 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 this program; if not, write to the Free Software
; Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
;

	;	-- TODO --
	;
	; \ がらみで、\n を書き込むのが \\n でできるようにする、とか
	; パラサイトの書き込みが上書きではなく、追加も選べるようにする (完了)
	; パラサイトの書き込みで、ターゲットパラサイトが存在しない場合は新規作成する
	; ターゲットオブジェクト Global が何だか変？
	; 全てを一つのダイアログで済ませるのではなく、目的別に分けようか？
	; パラサイトリストの取得表示時に、各パラサイト情報も表示する


	;; convert Integer into Chracter string 

(define (integer->char integer)
  (define (list-ref l n) (nth n l))
  (let* (                  ;   0    1    2    3    4    5    6    7    8    9
	 (character-code0  '("\N" "\1" "\2" "\3" "\d" "\5" "\6" "\7"   "" "\t"))
	 (character-code1  '("\n"   ""   "" "\r"   ""   ""   ""   ""   ""   ""))
	 (character-code2  '(  ""   ""   ""   ""   ""   ""   ""   ""   ""   ""))
	 (character-code3  '(  ""   ""  " "  "!" "\""  "#"  "$"  "%"  "&"  "'"))
	 (character-code4  '( "("  ")"  "*"  "+"  ","  "-"  "."  "/"  "0"  "1"))
	 (character-code5  '( "2"  "3"  "4"  "5"  "6"  "7"  "8"  "9"  ":"  ";"))
	 (character-code6  '( "<"  "="  ">"  "?"  "@"  "A"  "B"  "C"  "D"  "E"))
	 (character-code7  '( "F"  "G"  "H"  "I"  "J"  "K"  "L"  "M"  "N"  "O"))
	 (character-code8  '( "P"  "Q"  "R"  "S"  "T"  "U"  "V"  "W"  "X"  "Y"))
	 (character-code9  '( "Z"  "[" "\\"  "]"  "^"  "_"  "`"  "a"  "b"  "c"))
	 (character-code10 '( "d"  "e"  "f"  "g"  "h"  "i"  "j"  "k"  "l"  "m"))
	 (character-code11 '( "n"  "o"  "p"  "q"  "r"  "s"  "t"  "u"  "v"  "w"))
	 (character-code12 '( "x"  "y"  "z"  "{"  "|"  "}"  "~"  ""   ""   ""))
	 (character-code (append character-code0  character-code1  character-code2
	                         character-code3  character-code4  character-code5
	                         character-code6  character-code7  character-code8
	                         character-code9  character-code10 character-code11
	                         character-code12 ))
	 (result (if (and (<= 0 integer) (<= integer 127))	; always 0 <= number <= 127
	             (list-ref character-code integer)
	             (number->string integer)))	; debug output
	) ; end variable definition
  result
  ) ; end of let*
)


	;; View current parasites, or Read or Write or Remove a parasite

(define (script-fu-read-write-parasite
			img		;; target imgae
			drawable	;; target drawable
			method		;; show / read / overwrite /  addtional write /
			                ;; remove / create new / the parasite
			target-object	;; Image / Drawable / Global
			comment-number	;; target comment name to work
			string		;; parasite string to write (attacth)
			filename		;; export final result to file
	)

  (define (list-ref l n) (nth n l))

  (define (parasite-attach target parasite)
          (cond ((eqv? target-object 0) (gimp-image-parasite-attach target parasite))
                ((eqv? target-object 1) (gimp-drawable-parasite-attach target parasite))
                ((eqv? target-object 2) (gimp-parasite-attach parasite))))
  (define (parasite-detach target name)
          (cond ((eqv? target-object 0) (gimp-image-parasite-detach target name))
                ((eqv? target-object 1) (gimp-drawable-parasite-detach target name))
                ((eqv? target-object 2) (gimp-parasite-detach name))))
  (define (parasite-find target name)
          (cond ((eqv? target-object 0) (gimp-image-parasite-find target name))
                ((eqv? target-object 1) (gimp-drawable-parasite-find target name))
                ((eqv? target-object 2) (gimp-parasite-find name))))
  (define (parasite-list target)
          (cond ((eqv? target-object 0) (gimp-image-parasite-list target))
                ((eqv? target-object 1) (gimp-drawable-parasite-list target))
                ((eqv? target-object 2) (gimp-parasite-list))))

  (set! target-type (cond ((eqv? target-object 0) img)
                          ((eqv? target-object 1) drawable)
                          ((eqv? target-object 2) img)))	; what is global id?

  (set! type (cond ((eqv? target-object 0) "Image")
                   ((eqv? target-object 1) "Drawable")
                   ((eqv? target-object 2) "Global")))


;;;;;;;;;;;;;;;;;;;; Output final result to File or Display

  (set! export? (if (< 0 (string-length filename)) TRUE FALSE))

  (if (equal? export? TRUE)
      (set! outfile (fopen filename "w")))

  (define (output-result message)
    (if (equal? export? TRUE)
        (fwrite message outfile)
        (gimp-message message)))


;;;;;;;;;;;;;;;;;;;; Start

  (cond

;;;;;;;;;;;;;;;;;;;; Show current parasite list

    ((= method 0)

      (let* ((parasite-number (- (car (parasite-list target-type)) 1))
             (result-message (string-append "  <Current Parasite List>  \n"
                                            "              Object Type: " type "\n"))
             (count 0) )

        (if (= parasite-number -1)
            (gimp-message "Found not parasite information. Abort!")
            (begin
              (while (<= count parasite-number)
                (set! result-message
                          (string-append result-message "\n"
                                         "No." (number->string count) ": \""
                                         (list-ref (cadr (parasite-list target-type)) count)
                                         "\"\n"))
                (set! count (+ count 1))
              ) ; end of while
            (output-result result-message)
            ) ; end of begin
        ) ; end of if
      ) ; end of let*

    )


;;;;;;;;;;;;;;;;;;;; Read a parasite

    ((= method 1)

      (let* ((parasite-number (- (car (parasite-list target-type)) 1))
             (target-comment
                 (if (and (and (<= 0 comment-number) (<= comment-number parasite-number))
                          (not (= parasite-number -1)))
                     (list-ref (cadr (parasite-list target-type)) comment-number)
                     ""))
             (count 0) )

	;; find the location of target parasite name

        (if (= parasite-number -1)
            (gimp-message "Found not parasite information. Abort!")
            (if (not (and (<= 0 comment-number) (<= comment-number parasite-number)))
                (gimp-message "Incorrect Target comment No. Abort!")
                (begin
                  (while (and (< count parasite-number)
                              (not (equal? target-comment
                                           (list-ref (cadr (parasite-list target-type))
                                                     count))))
                    (set! count (+ count 1))
                  ) ; end of while

	;; extract the parasite contents

                  (let* ((result-message (string-append "Current parasite of \""
                                                        target-comment
                                                        "\" is\n"))
                         (parasite-comment
                                (car (cddar (parasite-find target-type target-comment))))
                         (parasite-comment-length (length parasite-comment))
                         (count2 0) )
                    (while (< count2 parasite-comment-length)
                      (set! result-message
                              (string-append result-message
                                             (integer->char
                                                 (aref parasite-comment count2))))
                      (set! count2 (+ count2 1))
                   ) ; end of while
                   (output-result result-message)
                  ) ; end of let*
                ) ; end of begin
            ) ; end of if
        ) ; end of if (= parasite-number -1)
      ) ; end of let*

    )


;;;;;;;;;;;;;;;;;;;; Overwrite a parasite

    ((= method 2)

      (let* ((flag 1)	; what means flag number? (1 = ?), (2 = ?), etc.
             (parasite-number (- (car (parasite-list target-type)) 1))
             (parasite-message (bytes-append (hexstr->bytes (array->hexstr string)) "\0"))
             (target-comment
                 (if (and (and (<= 0 comment-number) (<= comment-number parasite-number))
                          (not (= parasite-number -1)))
                     (list-ref (cadr (parasite-list target-type)) comment-number)
                     ""))
             (result-parasite (list target-comment flag parasite-message)) )

        (if (= parasite-number -1)
            (gimp-message "Found not parasite information. Abort!")
            (if (not (and (<= 0 comment-number) (<= comment-number parasite-number)))
                (gimp-message "Incorrect Target comment No. Abort!")
                (begin
                  (parasite-attach target-type result-parasite)
                  (gimp-message (string-append "Successful!\n"
                                               "Overwrited the \""
                                               string
                                               "\" at parasite named \""
                                               target-comment
                                               "\" in "
                                               type))
                ) ; end of begin
            ) ; end of if
        ) ; end of if (= parasite-number -1)
      ) ; end of let*

    )


;;;;;;;;;;;;;;;;;;;; Addtional write a parasite

    ((= method 3)

      (let* ((flag 1)	; what means flag number? (1 = ?), (2 = ?), etc.
             (parasite-number (- (car (parasite-list target-type)) 1))
             (parasite-message (bytes-append (hexstr->bytes (array->hexstr string)) "\0"))
             (target-comment
                 (if (and (and (<= 0 comment-number) (<= comment-number parasite-number))
                          (not (= parasite-number -1)))
                     (list-ref (cadr (parasite-list target-type)) comment-number)
                     "")) )

        (if (= parasite-number -1)
            (gimp-message "Found not parasite information. Abort!")
            (if (not (and (<= 0 comment-number) (<= comment-number parasite-number)))
                (gimp-message "Incorrect Target comment No. Abort!")
                (let* ((result-message "")
                       (parasite-comment
                              (car (cddar (parasite-find target-type target-comment))))
                       (result-message (bytes-append parasite-comment parasite-message))
                       (result-parasite (list target-comment flag result-message))
                      ) ; end of let*
                  (parasite-attach target-type result-parasite)
                  (gimp-message (string-append "Successful!\n"
                                               "Addtional writed the \""
                                               string
                                               "\" at parasite named \""
                                               target-comment
                                               "\" in "
                                               type))
                ) ; end of let*
            ) ; end of if
        ) ; end of if (= parasite-number -1)
      ) ; end of let*

    )


;;;;;;;;;;;;;;;;;;;; Remove a parasite

    ((= method 4)

      (let* ((parasite-number (- (car (parasite-list target-type)) 1))
             (target-comment
                 (if (and (and (<= 0 comment-number) (<= comment-number parasite-number))
                          (not (= parasite-number -1)))
                     (list-ref (cadr (parasite-list target-type)) comment-number)
                     "")) )

        (if (= parasite-number -1)
            (gimp-message "Found not parasite information. Abort!")
            (if (not (and (<= 0 comment-number) (<= comment-number parasite-number)))
                (gimp-message "Incorrect Target comment No. Abort!")
                (begin
                  (parasite-detach target-type target-comment)
                  (gimp-message (string-append "Successful!\n"
                                               "Removed the comment named \""
                                               target-comment
                                               "\" from parasite list in "
                                               type))
                ) ; end of begin
            ) ; end of if
        ) ; end of if (= parasite-number -1)
      ) ; end of let*

    )


;;;;;;;;;;;;;;;;;;;; Create new parasite

    ((= method 5)

      (let* ((flag 1)	; what means flag number? (1 = ?), (2 = ?), etc.
             (parasite-number (- (car (parasite-list target-type)) 1))
             (parasite-message "")
             (target-comment string)
             (result-parasite (list target-comment flag parasite-message))
             (flag FALSE)
             (count 0) )

        (if (equal? string "")
            (gimp-message "New comment name is empty. Abort!")
            (begin
              (while (< count parasite-number)
                (if (equal? target-comment
                            (list-ref (cadr (parasite-list target-type)) count))
                    (set! flag TRUE))
                (set! count (+ count 1))
              ) ; end of while
              (if (eqv? flag TRUE)
                  (gimp-message "The same comment name is existing. Abort!")
                  (begin
                    (parasite-attach target-type result-parasite)
                    (gimp-message (string-append "Successful!\n"
                                                 "Create new comment named \""
                                                 string
                                                 "\" at parasite list in "
                                                 type))
                  ) ; end of begin
              ) ; end of if
            ) ; end of begin
        ) ; end of if
      ) ; end of let*

    )


;;;;;;;;;;;;;;;;;;;; helper function (never used)

    ((= method 6)

      (define (array->list array)
        (let* ((array-size (- (length array) 1))
               (mylist '()))
          (while (>= array-size 0)
                 (set! local-array (aref array array-size))
                 (set! mylist (cons local-array mylist))
                 (set! array-size (- array-size 1))
          )
          mylist
        )
      )

      (let* ((listed-string (array->list (hexstr->bytes (array->hexstr string))))
             (list-length (length listed-string))
             (result-message (string-append "String \""
                                            string
                                            "\" is represented in Interger: \n("))
             (count 0) )
        (while (< count list-length)
          (set! result-message
                (string-append result-message " "
                               (number->string (list-ref listed-string count))))
          (set! count (+ count 1))
        ) ; end of while
        (set! result-message (string-append result-message " )"))
        (output-result result-message))

    )


;;;;;;;;;;;;;;;;;;;; end

  ) ; end of cond
  (if (equal? export? TRUE)
      (fclose outfile))
) ; end of define


(script-fu-register
  "script-fu-read-write-parasite"
  "<Image>/Script-Fu/Utils/Read or Write a Parasite..."
  "Read/Write a parasite"
  "Iccii <iccii@hotmail.com>"
  "Iccii"
  "2001, Sep"
  "RGB* GRAY* INDEXED*"
  SF-IMAGE      "Image"		0
  SF-DRAWABLE   "Drawable"	0
  SF-OPTION     "Method"		'("Show list"
                                          "Read"
                                          "Overwrite"
                                          "Addtional Write"
                                          "Remove"
                                          "Create New"
                                         ; "Convert into Integer"	;; don't use
                                         )
  SF-OPTION     "Target Object"		'("Image" "Drawable" "Global")
  SF-ADJUSTMENT "Target comment No."	'(0 0 127 1 10 0 1)
  SF-STRING     "String"		"Happy GIMPing!"
  SF-FILENAME   "Export Result to File" ""
)