;
; gpg-decode.l
; 4th July 2020 by Teruyoshi FUJIWARA <tf@dsl.gr.jp>
;
; This script decodes your encoded GPG file on xyzzy. You need GPG (GNU Privacy Guard) to
; use this script.

(defvar *gpg-command* "c:\\cygwin64\\bin\\gpg.exe --batch -d --passphrase")
(defvar *gpg-encoded-file* "c:\\path\\to\\your\\gpg\\file.gpg")

(defun gpg-decode ()
  (interactive)
  (set-buffer (get-buffer-create "*gpg-encoded*"))
  ; set buffer attributes
  (toggle-read-only nil)
  (set-buffer-eol-code 1)
  (gpg-decode-mode)
  (set-buffer-fileio-encoding *encoding-sjis*)
  
  (execute-shell-command (concat *gpg-command*
				 " "
				 (minibuffer-input-password "Enter password:")
				 " "
				 *gpg-encoded-file*)
			 t
			 (selected-buffer))
  (replace-buffer "^gpg:.*\n" "" :regexp t)
  (goto-char (point-min))
  (replace-buffer "
" "")
  (goto-char (point-min))
  (delete-char 2)
  (toggle-read-only t)
  )

(defun minibuffer-input-password (prompt)
  (interactive)
  (let ((ans ""))
    (loop
      (minibuffer-prompt (concat prompt (repeat-string "." (length ans))))
      (let ((c (read-char *keyboard*)))
	(case c
	  (#\RET (return ans))
	  (#\C-g (quit))
	  (#\C-h (setq ans (if (> (length ans) 0)
			       (subseq ans 0 (- (length ans) 1))
			     ans)))
	  (t (setq ans (format nil "~a~c" ans c))))))))

(defun gpg-decode-mode ()
  (kill-all-local-variables)
  
  (setq buffer-mode 'gpg-decode-mode)
  (setq mode-name "Gpg-decode")
  
  ; keymap
  (use-keymap *gpg-decode-mode-map*)
  
  (make-local-variable 'need-not-save)
  (setq need-not-save t)
  (make-local-variable 'auto-save)
  (setq auto-save nil)

  (make-local-variable 'regexp-keyword-list)
  (setq regexp-keyword-list
	(compile-regexp-keyword-list
	 '(
	   ;見出し
	   ("^・.+$" t (:keyword 0 :bold) t)))))
  
(defvar *gpg-decode-mode-map* nil)
(unless *gpg-decode-mode-map*
  (setq *gpg-decode-mode-map* (make-sparse-keymap))
  (define-key *gpg-decode-mode-map* #\SPC 'gpg-decode-next-page)
  (define-key *gpg-decode-mode-map* #\C-h 'gpg-decode-prev-page)
  (define-key *gpg-decode-mode-map* #\n 'gpg-decode-next-item)
  (define-key *gpg-decode-mode-map* #\p 'gpg-decode-prev-item)
  (define-key *gpg-decode-mode-map* #\q 'gpg-decode-quit))

(defun gpg-decode-prev-page ()
  (interactive)
  (previous-page))

(defun gpg-decode-next-page ()
  (interactive)
  (next-page))

(defun gpg-decode-next-item ()
  (interactive)
  (forward-char)
  (or (scan-buffer "^・" :regexp t) (backward-char)))

(defun gpg-decode-prev-item ()
  (interactive)
  (backward-char)
  (or (scan-buffer "^・" :regexp t :reverse t) (forward-char)))

(defun gpg-decode-quit ()
  (interactive)
  (delete-buffer "*gpg-encoded*"))