;;; pdx-mode.el --- mode for editing pdx code

;; Author:     Harry G. George  <hgg9140@seanet.com>
;; Maintainer: Harry G. George  <hgg9140@seanet.com>
;; Keywords:   tools, languages

;; This file is to be used with GNU Emacs.


;;;Commentary:
;; This mode was written by following the pattern in several of 
;; the other modes, esp: asm, prolog, scheme, and tcl.

;; Somewhere in the .emacs process, assure this is handled:
;; 
;; (load "/path-to-modes/pdx-mode")
;; (setq auto-mode-alist
;;       (append
;;        '(("\\.pdx\\'" . pdx-mode))
;;        auto-mode-alist))

;;; Code:

;---group---
(defgroup pdx nil
  "Mode for editing pdx code."
  :group 'languages)

;---syntax---
(defvar pdx-mode-syntax-table nil
  "Syntax table used while in Pdx mode.")

(if pdx-mode-syntax-table
    nil ;Do not change the table if it is already set up.
  (setq pdx-mode-syntax-table (make-syntax-table))
  (modify-syntax-entry ?\\ "\\" pdx-mode-syntax-table)
  )
 
;---abbrev---
(defvar pdx-mode-abbrev-table nil
  "Abbrev table used while in Pdx mode.")
(define-abbrev-table 'pdx-mode-abbrev-table ())

;---mode map---
(defvar pdx-mode-map nil
  "Keymap for Pdx mode.")

(if pdx-mode-map 
    nil
  (setq pdx-mode-map (make-sparse-keymap))
  (define-key pdx-mode-map "\177"     'backward-delete-char-untabify)
  (define-key pdx-mode-map "\C-X\C-S" 'pdx-maybe-run-on-save)
  )

;---font-lock---
(defconst pdx-font-lock-keywords
   (list
    ;; comments
    (list "^\\s-*\\(#.*\\)" '(1 font-lock-comment-face))
    ;;"=" markers
    (list (concat "^\\s-*\\(=" 
		  (regexp-opt  '("begin" "center" "cfg" "def" "end" "for" "head" "include"
                         "include_verbatim" "include_for" "quote" "table" "row" 
                         "pathpush" "pathpop" "list" "item" 
                         "preamble_begin_for" "preamble_append_for" "preamble_end_for"
                         "postamble_for" "verbatim") t)
		  "\\)") 
	  '(1 font-lock-keyword-face))
    ;; in-line markers
    (list (concat "\\<\\("
		  (regexp-opt '("B" "C" "E" "I" "L" "N" "T" "X") t)
		  "<[^>]*>\\)")
	  '(1 font-lock-variable-name-face))	  
    ))

;---hooks---
(defun redefine-save-menu ()
  (define-key menu-bar-files-menu [save-buffer] 
    '("Save Buffer" . pdx-maybe-run-on-save)))


;---edit functions---
(defun pdx-newline ()
  "Insert LFD + fill-prefix, to bring us back to code-indent level."
  (interactive)
  (if (eolp) (delete-horizontal-space))
  (insert "\n")
  (tab-to-tab-stop)
  )

;;;==========================================================
;;;Compiling the buffer...

(defcustom pdx-run-on-save nil
  "run pdx program after a file is saved"
  :type 'boolean
  :group 'pdx)

(defcustom pdx-program-name "pdx2html.py"
  "Program name for invoking an inferior process with `run-pdx'."
  :type 'string
  :group 'pdx)

(defcustom pdx-program-options ""
  "Command line options for `run-pdx'.  E.g., --notoc"
  :type 'string
  :group 'pdx)

(defcustom pdx-eof-string nil
  "*String that represents end of file for pdx.
nil means send actual operating system end of file."
  :type 'string
  :group 'pdx)

(defun pdx-run ()
  "*function used to run pdx on the current buffer."
  (interactive)
  (if (buffer-modified-p)
      (progn 
        (save-buffer)
	(shell-command (concat pdx-program-name " "
			       pdx-program-options " "
			       buffer-file-name 
			       ))
	)))

(defun pdx-maybe-run-on-save ()
  "runs pdx on current buffer if \\
   pdx-run-on-save is set to true"
  (interactive)
  (if pdx-run-on-save
      (pdx-run)
      (save-buffer)))

;;;=============================================

;;;###autoload
(defun pdx-mode ()
  "Major mode for editing typical pdx code.
"
  (interactive)
  (kill-all-local-variables)
  (setq mode-name "Pdx")
  (setq major-mode 'pdx-mode)
  (setq local-abbrev-table pdx-mode-abbrev-table)
  (make-local-variable 'font-lock-defaults)
  (setq font-lock-defaults '(pdx-font-lock-keywords
			     't   ; keywords only
			     nil ; not ignore case
			     nil ; syntax table
			     nil ; syntax beginning
			     ))
  (set-syntax-table pdx-mode-syntax-table)
  (use-local-map pdx-mode-map)
  (make-local-variable 'menu-bar-files-menu)
  (redefine-save-menu)
  (add-hook 'pdx-mode-hook 'turn-on-font-lock)
  (run-hooks 'pdx-mode-hook)
  )

(provide 'pdx-mode)

;;; pdx-mode.el ends here