;;; pces-om.el --- pces implementation for Mule 1.* and Mule 2.*

;; Copyright (C) 1995,1996,1997,1998,1999 Free Software Foundation, Inc.

;; Author: MORIOKA Tomohiko <tomo@m17n.org>
;;         Katsumi Yamaoka  <yamaoka@jpl.org>
;; Keywords: emulation, compatibility, Mule

;; This file is part of APEL (A Portable Emacs Library).

;; 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, 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.

;;; Code:

(require 'poe)


;;; @ version specific features
;;;

(cond ((= emacs-major-version 19)
       (define-ccl-program poem-ccl-decode-raw-text
	 '(1
	   ((r2 = 0)
	    (read r0)
	    (loop
	      (if (r0 == ?\x0d)
		  ((r2 = 1)
		   (read-if (r1 == ?\x0a)
			    ((r0 = ?\x0a)
			     (r2 = 0)
			     (write-read-repeat r0))
			    ((write r0)
			     (r0 = (r1 + 0))
			     (repeat))))
		((r2 = 0)
		 (write-read-repeat r0)))))
	   ;; This EOF BLOCK won't work out in practice. So the last datum
	   ;; might be lost if it's value is ?\x0d.
	   (if r2
	       (write r0))
	   )
	 "Convert line-break code from CRLF to LF.")

       (define-ccl-program poem-ccl-encode-raw-text
	 '(1
	   ((read r0)
	    (loop (write-read-repeat r0))))
	 "Pass through without any conversions.")

       (define-ccl-program poem-ccl-encode-raw-text-CRLF
	 '(2
	   ((loop
	      (read-if (r0 == ?\x0a)
		       (write "\x0d\x0a")
		       (write r0))
	      (repeat))))
	 "Convert line-break code from LF to CRLF.")

       (make-coding-system
	'raw-text 4 ?=
	"No conversion"
	nil
	(cons poem-ccl-decode-raw-text poem-ccl-encode-raw-text))

       (make-coding-system
	'raw-text-dos 4 ?=
	"No conversion"
	nil
	(cons poem-ccl-decode-raw-text poem-ccl-encode-raw-text-CRLF))
       )
      (t
       (defun poem-decode-raw-text (from to)
	 (save-restriction
	   (narrow-to-region from to)
	   (goto-char (point-min))
	   (while (re-search-forward "\r$" nil t)
	     (replace-match "")
	     )))
       (defun poem-encode-raw-text-CRLF (from to)
	 (save-restriction
	   (narrow-to-region from to)
	   (goto-char (point-min))
	   (while (re-search-forward "\\(\\=\\|[^\r]\\)\n" nil t)
	     (replace-match "\\1\r\n")
	     )))

       (make-coding-system 'raw-text nil ?= "No conversion")
       (put 'raw-text 'post-read-conversion 'poem-decode-raw-text)
       
       (make-coding-system 'raw-text-dos nil ?= "No conversion")
       (put 'raw-text-dos 'post-read-conversion 'poem-decode-raw-text)
       (put 'raw-text-dos 'pre-write-conversion 'poem-encode-raw-text-CRLF)
       ))


;;; @ coding system
;;;

(defun-maybe find-coding-system (obj)
  "Return OBJ if it is a coding-system."
  (if (coding-system-p obj)
      obj))

(defun encode-coding-region (start end coding-system)
  "Encode the text between START and END to CODING-SYSTEM.
\[EMACS 20 emulating function]"
  ;; If `coding-system' is nil, do nothing.
  (code-convert-region start end *internal* coding-system))

(defun decode-coding-region (start end coding-system)
  "Decode the text between START and END which is encoded in CODING-SYSTEM.
\[EMACS 20 emulating function]"
  ;; If `coding-system' is nil, do nothing.
  (code-convert-region start end coding-system *internal*))

;; XXX: Should we support optional NOCOPY argument? (only in Emacs 20.x)
(defun encode-coding-string (str coding-system)
  "Encode the STRING to CODING-SYSTEM.
\[EMACS 20 emulating function]"
  (if coding-system
      (code-convert-string str *internal* coding-system)
    ;;(code-convert-string str *internal* nil) returns nil instead of str.
    str))

;; XXX: Should we support optional NOCOPY argument? (only in Emacs 20.x)
(defun decode-coding-string (str coding-system)
  "Decode the string STR which is encoded in CODING-SYSTEM.
\[EMACS 20 emulating function]"
  (if coding-system
      (let ((len (length str))
	    ret)
	(while (and (< 0 len)
		    (null (setq ret
				(code-convert-string
				 (substring str 0 len)
				 coding-system *internal*))))
	  (setq len (1- len)))
	(concat ret (substring str len)))
    str))

(defalias 'detect-coding-region 'code-detect-region)

(defalias 'set-buffer-file-coding-system 'set-file-coding-system)


;;; @ with code-conversion
;;;

(cond
 ((and (>= emacs-major-version 19) (>= emacs-minor-version 23))
  ;; Mule 2.0 or later.
  (defun insert-file-contents-as-coding-system
    (coding-system filename &optional visit beg end replace)
    "Like `insert-file-contents', q.v., but CODING-SYSTEM the first arg will
be applied to `file-coding-system-for-read'."
    (let ((file-coding-system-for-read coding-system))
      (insert-file-contents filename visit beg end replace))))
 (t
  ;; Mule 1.1 or earlier.
  (defun insert-file-contents-as-coding-system
    (coding-system filename &optional visit beg end replace)
    "Like `insert-file-contents', q.v., but CODING-SYSTEM the first arg will
be applied to `file-coding-system-for-read'."
    (let ((file-coding-system-for-read coding-system))
      (insert-file-contents filename visit)))))

(cond
 ((and (>= emacs-major-version 19) (>= emacs-minor-version 29))
  ;; for MULE 2.3 based on Emacs 19.34.
  (defun write-region-as-coding-system
    (coding-system start end filename &optional append visit lockname)
    "Like `write-region', q.v., but CODING-SYSTEM the first arg will be
applied to `file-coding-system'."
    (let ((file-coding-system coding-system)
	  jka-compr-compression-info-list jam-zcat-filename-list)
      (write-region start end filename append visit lockname)))

  (defun find-file-noselect-as-coding-system
    (coding-system filename &optional nowarn rawfile)
    "Like `find-file-noselect', q.v., but CODING-SYSTEM the first arg will
be applied to `file-coding-system-for-read'."
    (let ((file-coding-system-for-read coding-system))
      (find-file-noselect filename nowarn rawfile)))
  )
 (t
  ;; for MULE 2.3 based on Emacs 19.28 or MULE 1.*.
  (defun write-region-as-coding-system
    (coding-system start end filename &optional append visit lockname)
    "Like `write-region', q.v., but CODING-SYSTEM the first arg will be
applied to `file-coding-system'."
    (let ((file-coding-system coding-system)
	  jka-compr-compression-info-list jam-zcat-filename-list)
      (write-region start end filename append visit)))

  (defun find-file-noselect-as-coding-system
    (coding-system filename &optional nowarn rawfile)
    "Like `find-file-noselect', q.v., but CODING-SYSTEM the first arg will
be applied to `file-coding-system-for-read'."
    (let ((file-coding-system-for-read coding-system))
      (find-file-noselect filename nowarn)))
  ))

(defun save-buffer-as-coding-system (coding-system &optional args)
  "Like `save-buffer', q.v., but CODING-SYSTEM the first arg will be
applied to `coding-system-for-write'."
  (let ((file-coding-system coding-system))
    (save-buffer args)))


;;; @ without code-conversion
;;;

(make-coding-system 'binary nil ?= "No conversion")

(defmacro as-binary-process (&rest body)
  (` (let (selective-display	; Disable ^M to nl translation.
	   ;; Mule
	   mc-flag
	   (default-process-coding-system (cons *noconv* *noconv*))
	   program-coding-system-alist)
       (,@ body))))

(defmacro as-binary-input-file (&rest body)
  (` (let (mc-flag
	   (file-coding-system-for-read *noconv*)
	   )
       (,@ body))))

(defmacro as-binary-output-file (&rest body)
  (` (let (mc-flag
	   (file-coding-system *noconv*)
	   )
       (,@ body))))

(defalias 'set-process-input-coding-system 'set-process-coding-system)

(cond
 ((and (>= emacs-major-version 19) (>= emacs-minor-version 23))
  ;; Mule 2.0 or later.
  (defun insert-file-contents-as-binary (filename
					 &optional visit beg end replace)
    "Like `insert-file-contents', q.v., but don't code and format conversion.
Like `insert-file-contents-literary', but it allows find-file-hooks,
automatic uncompression, etc.

Namely this function ensures that only format decoding and character
code conversion will not take place."
    (as-binary-input-file
     ;; Returns list absolute file name and length of data inserted.
     (insert-file-contents filename visit beg end replace))))
 (t
  ;; Mule 1.1 or earlier.
  (defun insert-file-contents-as-binary (filename
					 &optional visit beg end replace)
    "Like `insert-file-contents', q.v., but don't code and format conversion.
Like `insert-file-contents-literary', but it allows find-file-hooks,
automatic uncompression, etc.

Namely this function ensures that only format decoding and character
code conversion will not take place."
    (as-binary-input-file
     ;; Returns list absolute file name and length of data inserted.
     (insert-file-contents filename visit)))))

(defun insert-file-contents-as-raw-text (filename
					 &optional visit beg end replace)
  "Like `insert-file-contents', q.v., but don't code and format conversion.
Like `insert-file-contents-literary', but it allows find-file-hooks,
automatic uncompression, etc.
Like `insert-file-contents-as-binary', but it converts line-break
code."
  ;; Returns list absolute file name and length of data inserted.
  (insert-file-contents-as-coding-system 'raw-text
					 filename visit beg end replace))

(defalias 'insert-file-contents-as-raw-text-CRLF
  'insert-file-contents-as-raw-text)

(defun write-region-as-binary (start end filename
				     &optional append visit lockname)
  "Like `write-region', q.v., but don't code conversion."
  (write-region-as-coding-system 'binary
				 start end filename append visit lockname))

(defun write-region-as-raw-text-CRLF (start end filename
					    &optional append visit lockname)
  "Like `write-region', q.v., but don't code conversion."
  (write-region-as-coding-system 'raw-text-dos
				 start end filename append visit lockname))

(defun find-file-noselect-as-binary (filename &optional nowarn rawfile)
  "Like `find-file-noselect', q.v., but don't code and format conversion."
  (find-file-noselect-as-coding-system 'binary filename nowarn rawfile))

(defun find-file-noselect-as-raw-text (filename &optional nowarn rawfile)
  "Like `find-file-noselect', q.v., but it does not code and format
conversion except for line-break code."
  (find-file-noselect-as-coding-system 'raw-text filename nowarn rawfile))

(defalias 'find-file-noselect-as-raw-text-CRLF
  'find-file-noselect-as-raw-text)

(defun save-buffer-as-binary (&optional args)
  "Like `save-buffer', q.v., but don't encode."
  (let ((file-coding-system 'binary))
    (save-buffer args)))

(defun save-buffer-as-raw-text-CRLF (&optional args)
  "Like `save-buffer', q.v., but save as network representation."
  (let ((file-coding-system 'raw-text-dos))
    (save-buffer args)))

(defun open-network-stream-as-binary (name buffer host service)
  "Like `open-network-stream', q.v., but don't code conversion."
  (let ((process (open-network-stream name buffer host service)))
    (set-process-coding-system process *noconv* *noconv*)
    process))


;;; @ end
;;;

(require 'product)
(product-provide (provide 'pces-om) (require 'apel-ver))

;;; pces-om.el ends here