;;; mlsupport.el --- run-time support for mocklisp code

;; Copyright (C) 1985 Free Software Foundation, Inc.

;; Maintainer: FSF
;; Keywords: extensions

;; This file is part of GNU Emacs.

;; GNU Emacs 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.

;; GNU Emacs 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., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.

;;; Commentary:

;; This package provides equivalents of certain primitives from Gosling
;; Emacs (including the commercial UniPress versions).  These have an
;; ml- prefix to distinguish them from native GNU Emacs functions with
;; similar names.  The package mlconvert.el translates Mocklisp code
;; to use these names.

;;; Code:

(defmacro ml-defun (&rest defs)
  (list 'ml-defun-1 (list 'quote defs)))

(defun ml-defun-1 (args)
  (while args
    (fset (car (car args)) (cons 'mocklisp (cdr (car args))))
    (setq args (cdr args))))

(defmacro declare-buffer-specific (&rest vars)
  (cons 'progn (mapcar (function (lambda (var) (list 'make-variable-buffer-local (list 'quote var)))) vars)))

(defun ml-set-default (varname value)
  (set-default (intern varname) value))

; Lossage: must make various things default missing args to the prefix arg
; Alternatively, must make provide-prefix-argument do something hairy.

(defun >> (val count) (lsh val (- count)))
(defun novalue () nil)

(defun ml-not (arg) (if (zerop arg) 1 0))

(defun provide-prefix-arg (arg form)
  (funcall (car form) arg))

(defun define-keymap (name)
  (fset (intern name) (make-keymap)))

;; Make it work to use ml-use-...-map on "esc" and such.
(fset 'esc-map esc-map)
(fset 'ctl-x-map ctl-x-map)

(defun ml-use-local-map (name)
  (use-local-map (intern (concat name "-map"))))

(defun ml-use-global-map (name)
  (use-global-map (intern (concat name "-map"))))

(defun local-bind-to-key (name key)
  (or (current-local-map)
      (use-local-map (make-keymap)))
  (define-key (current-local-map)
    (if (integerp key)
	(if (>= key 128)
	    (concat (char-to-string meta-prefix-char)
		    (char-to-string (- key 128)))
	  (char-to-string key))
      key)
    (intern name)))

(defun bind-to-key (name key)
  (define-key global-map (if (integerp key) (char-to-string key) key)
    (intern name)))

(defun ml-autoload (name file)
  (autoload (intern name) file))

(defun ml-define-string-macro (name defn)
  (fset (intern name) defn))

(defun push-back-character (char)
  (setq unread-command-events (list char)))

(defun to-col (column)
  (indent-to column 0))

(defmacro is-bound (&rest syms)
  (cons 'and (mapcar (function (lambda (sym) (list 'boundp (list 'quote sym)))) syms)))

(defmacro declare-global (&rest syms)
  (cons 'progn (mapcar (function (lambda (sym) (list 'defvar sym nil))) syms)))

(defmacro error-occurred (&rest body)
  (list 'condition-case nil (cons 'progn (append body '(nil))) '(error t)))

(defun return-prefix-argument (value)
  (setq prefix-arg value))

(defun ml-prefix-argument ()
  (if (null current-prefix-arg) 1
    (if (listp current-prefix-arg) (car current-prefix-arg)
      (if (eq current-prefix-arg '-) -1
	current-prefix-arg))))

(defun ml-print (varname)
  (interactive "vPrint variable: ")
  (if (boundp varname)
    (message "%s => %s" (symbol-name varname) (symbol-value varname))
    (message "%s has no value" (symbol-name varname))))

(defun ml-set (str val) (set (intern str) val))

(defun ml-message (&rest args) (message "%s" (apply 'concat args)))

(defun kill-to-end-of-line ()
  (ml-prefix-argument-loop
    (if (eolp)
	(kill-region (point) (1+ (point)))
      (kill-region (point) (if (search-forward ?\n nil t)
			       (1- (point)) (point-max))))))

(defun set-auto-fill-hook (arg)
  (setq auto-fill-function (intern arg)))

(defun auto-execute (function pattern)
  (if (/= (aref pattern 0) ?*)
      (error "Only patterns starting with * supported in auto-execute"))
  (setq auto-mode-alist (cons (cons (concat "\\." (substring pattern 1)
					    "\\'")
				    function)
			      auto-mode-alist)))

(defun move-to-comment-column ()
  (indent-to comment-column))

(defun erase-region ()
  (delete-region (point) (mark)))

(defun delete-region-to-buffer (bufname)
  (copy-to-buffer bufname (point) (mark))
  (delete-region (point) (mark)))

(defun copy-region-to-buffer (bufname)
  (copy-to-buffer bufname (point) (mark)))

(defun append-region-to-buffer (bufname)
  (append-to-buffer bufname (point) (mark)))

(defun prepend-region-to-buffer (bufname)
  (prepend-to-buffer bufname (point) (mark)))

(defun delete-next-character ()
  (delete-char (ml-prefix-argument)))

(defun delete-next-word ()
  (delete-region (point) (progn (forward-word (ml-prefix-argument)) (point))))

(defun delete-previous-word ()
  (delete-region (point) (progn (backward-word (ml-prefix-argument)) (point))))

(defun delete-previous-character ()
  (delete-backward-char (ml-prefix-argument)))

(defun forward-character ()
  (forward-char (ml-prefix-argument)))

(defun backward-character ()
  (backward-char (ml-prefix-argument)))

(defun ml-newline ()
  (newline (ml-prefix-argument)))

(defun ml-next-line ()
  (next-line (ml-prefix-argument)))

(defun ml-previous-line ()
  (previous-line (ml-prefix-argument)))

(defun delete-to-kill-buffer ()
  (kill-region (point) (mark)))

(defun narrow-region ()
  (narrow-to-region (point) (mark)))

(defun ml-newline-and-indent ()
  (let ((column (current-indentation)))
    (newline (ml-prefix-argument))
    (indent-to column)))

(defun newline-and-backup ()
  (open-line (ml-prefix-argument)))

(defun quote-char ()
  (quoted-insert (ml-prefix-argument)))

(defun ml-current-column ()
  (1+ (current-column)))

(defun ml-current-indent ()
  (1+ (current-indentation)))

(defun region-around-match (&optional n)
  (set-mark (match-beginning n))
  (goto-char (match-end n)))

(defun region-to-string ()
  (buffer-substring (min (point) (mark)) (max (point) (mark))))

(defun use-abbrev-table (name)
  (let ((symbol (intern (concat name "-abbrev-table"))))
    (or (boundp symbol)
	(define-abbrev-table symbol nil))
    (symbol-value symbol)))

(defun define-hooked-local-abbrev (name exp hook)
  (define-abbrev local-abbrev-table name exp (intern hook)))

(defun define-hooked-global-abbrev (name exp hook)
  (define-abbrev global-abbrev-table name exp (intern hook)))

(defun case-word-lower ()
  (ml-casify-word 'downcase-region))

(defun case-word-upper ()
  (ml-casify-word 'upcase-region))

(defun case-word-capitalize ()
  (ml-casify-word 'capitalize-region))

(defun ml-casify-word (fun)
  (save-excursion
   (forward-char 1)
   (forward-word -1)
   (funcall fun (point)
	    (progn (forward-word (ml-prefix-argument))
		   (point)))))

(defun case-region-lower ()
  (downcase-region (point) (mark)))

(defun case-region-upper ()
  (upcase-region (point) (mark)))

(defun case-region-capitalize ()
  (capitalize-region (point) (mark)))

(defvar saved-command-line-args nil)

(defun argc ()
  (or saved-command-line-args
      (setq saved-command-line-args command-line-args
	    command-line-args ()))
  (length command-line-args))

(defun argv (i)
  (or saved-command-line-args
      (setq saved-command-line-args command-line-args
	    command-line-args ()))
  (nth i saved-command-line-args))

(defun invisible-argc ()
  (length (or saved-command-line-args
	      command-line-args)))

(defun invisible-argv (i)
  (nth i (or saved-command-line-args
	     command-line-args)))

(defun exit-emacs ()
  (interactive)
  (condition-case ()
      (exit-recursive-edit)
    (error (kill-emacs))))

;; Lisp function buffer-size returns total including invisible;
;; mocklisp wants just visible.
(defun ml-buffer-size ()
  (- (point-max) (point-min)))

(defun previous-command ()
  last-command)

(defun beginning-of-window ()
  (goto-char (window-start)))

(defun end-of-window ()
  (goto-char (window-start))
  (vertical-motion (- (window-height) 2)))

(defun ml-search-forward (string)
  (search-forward string nil nil (ml-prefix-argument)))

(defun ml-re-search-forward (string)
  (re-search-forward string nil nil (ml-prefix-argument)))

(defun ml-search-backward (string)
  (search-backward string nil nil (ml-prefix-argument)))

(defun ml-re-search-backward (string)
  (re-search-backward string nil nil (ml-prefix-argument)))

(defvar use-users-shell 1
  "Mocklisp compatibility variable; 1 means use shell from SHELL env var.
0 means use /bin/sh.")

(defvar use-csh-option-f 1
  "Mocklisp compatibility variable; 1 means pass -f when calling csh.")

(defun filter-region (command)
  (let ((shell (if (/= use-users-shell 0) shell-file-name "/bin/sh"))
	(csh (equal (file-name-nondirectory shell) "csh")))
    (call-process-region (point) (mark) shell t t nil
			 (if (and csh use-csh-option-f) "-cf" "-c")
			 (concat "exec " command))))

(defun execute-monitor-command (command)
  (let ((shell (if (/= use-users-shell 0) shell-file-name "/bin/sh"))
	(csh (equal (file-name-nondirectory shell) "csh")))
    (call-process shell nil t t
		  (if (and csh use-csh-option-f) "-cf" "-c")
		  (concat "exec " command))))

(defun use-syntax-table (name)
  (set-syntax-table (symbol-value (intern (concat name "-syntax-table")))))

(defun line-to-top-of-window ()
  (recenter (1- (ml-prefix-argument))))

(defun ml-previous-page (&optional arg)
  (let ((count (or arg (ml-prefix-argument))))
    (while (> count 0)
      (scroll-down nil)
      (setq count (1- count)))
    (while (< count 0)
      (scroll-up nil)
      (setq count (1+ count)))))

(defun ml-next-page ()
  (previous-page (- (ml-prefix-argument))))

(defun page-next-window (&optional arg)
  (let ((count (or arg (ml-prefix-argument))))
    (while (> count 0)
      (scroll-other-window nil)
      (setq count (1- count)))
    (while (< count 0)
      (scroll-other-window '-)
      (setq count (1+ count)))))

(defun ml-next-window ()
  (select-window (next-window)))

(defun ml-previous-window ()
  (select-window (previous-window)))

(defun scroll-one-line-up ()
  (scroll-up (ml-prefix-argument)))

(defun scroll-one-line-down ()
  (scroll-down (ml-prefix-argument)))

(defun split-current-window ()
  (split-window (selected-window)))

(defun last-key-struck () last-command-char)

(defun execute-mlisp-line (string)
  (eval (read string)))

(defun move-dot-to-x-y (x y)
  (goto-char (window-start (selected-window)))
  (vertical-motion (1- y))
  (move-to-column (1- x)))

(defun ml-modify-syntax-entry (string)
  (let ((i 5)
	(len (length string))
	(datastring (substring string 0 2)))
    (if (= (aref string 0) ?\-)
	(aset datastring 0 ?\ ))
    (if (= (aref string 2) ?\{)
	(if (= (aref string 4) ?\ )
	    (aset datastring 0 ?\<)
	  (error "Two-char comment delimiter: use modify-syntax-entry directly")))
    (if (= (aref string 3) ?\})
	(if (= (aref string 4) ?\ )
	    (aset datastring 0 ?\>)
	  (error "Two-char comment delimiter: use modify-syntax-entry directly")))
    (while (< i len)
      (modify-syntax-entry (aref string i) datastring)
      (setq i (1+ i))
      (if (and (< i len)
	       (= (aref string i) ?\-))
	  (let ((c (aref string (1- i)))
		(lim (aref string (1+ i))))
	    (while (<= c lim)
	      (modify-syntax-entry c datastring)
	      (setq c (1+ c)))
	    (setq i (+ 2 i)))))))



(defun ml-substr (string from to)
  (let ((length (length string)))
    (if (< from 0) (setq from (+ from length)))
    (if (< to 0) (setq to (+ to length)))
    (substring string from (+ from to))))

(defun ml-concat (&rest args)
  (let ((newargs nil) this)
    (while args
      (setq this (car args))
      (if (numberp this)
	  (setq this (number-to-string this)))
      (setq newargs (cons this newargs)
	    args (cdr args)))
    (apply 'concat (nreverse newargs))))

(provide 'mlsupport)

;;; mlsupport.el ends here
