;;; gadict-mode.el --- major mode for editing gadict dictionary source files

;; Copyright (C) 2016 by Oleksandr Gavenko <gavenkoa@gmail.com>

;; You can do anything with this file without any warranty.

;; Author: Oleksandr Gavenko <gavenkoa@gmail.com>

;; Maintainer: Oleksandr Gavenko <gavenkoa@gmail.com>

;; Created: 2016

;; Keywords: dict, dictionary

;;; Commentary:

;;

;; File association can be registered by:

;;

;;   (add-to-list 'auto-mode-alist (cons "\\.gadict$" 'gadict-mode))

;;; Code:

(defvar gadict-font-lock-keywords

  '( ("^\\(_\\{2\\}\\)\n\n\\(\\w.*\\)$" (1 font-lock-function-name-face) (2 font-lock-keyword-face))

     ("^#.*" . font-lock-comment-face)

     ("^ +\\[[^]\n]+]" . font-lock-type-face)

     ("^\\(?:en\\|ru\\|uk\\|la\\): " . font-lock-type-face)

     ("^\\(?:en\\|ru\\|uk\\|la\\)> " . font-lock-doc-face)

     ("^\\(?:topic\\|ant\\|syn\\): " . font-lock-doc-face)

     ("^ +\\(?:v1\\|v2\\|v3\\|s\\|pl\\|male\\|female\\)$" . font-lock-doc-face)

     ("^\\(?:n\\|v\\|phr\\.v\\|adj\\|adv\\|pron\\|prep\\|num\\|conj\\|int\\)$" . font-lock-type-face) ))

(defun gadict-setup-fontlock ()

  (setq font-lock-defaults

        '(gadict-font-lock-keywords

          t nil nil nil

          (font-lock-multiline . t) ))

  (add-hook 'font-lock-extend-region-functions 'gadict-font-lock-extend-region t) )

(defun gadict-setup-comment ()

  (set (make-local-variable 'comment-start)  "#")

  (set (make-local-variable 'comment-continue)  nil)

  (set (make-local-variable 'comment-end)  "")

  (set (make-local-variable 'comment-end-skip)  nil)

  (set (make-local-variable 'comment-multi-line)  nil)

  (set (make-local-variable 'comment-use-syntax)  nil) )

(defun gadict-setup-paragraph ()

  (set (make-local-variable 'paragraph-separate)  "__$")

  (set (make-local-variable 'paragraph-start)  "__$") )

(defun gadict-setup-page ()

  (set (make-local-variable 'page-delimiter)  "__$") )

(defun gadict-setup-syntax ()

  (modify-syntax-entry ?' "w"))

(eval-when-compile

  (defvar font-lock-beg)

  (defvar font-lock-end))

(defun gadict-font-lock-extend-region ()

  "Look for '__' expression and extend `font-lock-beg' and `font-lock-end'."

  ;; (message "%d:%d, %d lines" font-lock-beg font-lock-end (count-lines font-lock-beg font-lock-end))

  (cond

   ((and

     (< (count-lines font-lock-beg font-lock-end) 5)

     (not (and (<= (point-max) font-lock-end) (<= font-lock-beg (point-min)) )))

    (save-excursion

      (goto-char font-lock-beg)

      (forward-line -2)

      (setq font-lock-beg (point))

      (goto-char font-lock-end)

      (forward-line 3)

      (setq font-lock-end (point))

      )

    t)

   (t nil) ))

(defvar-local gadict-tr nil

  "Translation markers as string separated by comma. Define own

  values in .dir-local.el or as -*- gadict-tr: \"...\" -*- file prelude")

(defun gadict-new-entry ()

  "Insert new entry template."

  (interactive)

  (if (re-search-forward "^__" nil t)

      (beginning-of-line)

    (goto-char (point-max)))

  (while (eq (char-before) ?\n)

    (delete-backward-char 1))

  (insert-char ?\n)

  (insert-char ?_ 2)

  (insert-char ?\n 3)

  (when (stringp gadict-tr)

    (mapc (lambda (tr)

            (insert-char ?\n)

            (insert tr)

            (insert ": "))

          (split-string gadict-tr ","))

    (insert-char ?\n)

    (re-search-backward "^$"))

  (backward-char))

(defun gadict-setup-keymap ()

  (define-key gadict-mode-map [C-return] 'gadict-new-entry))

;;;###autoload

(define-derived-mode gadict-mode fundamental-mode "gadict"

  "Derived mode for editing gadict dictionary source files."

  (gadict-setup-fontlock)

  (gadict-setup-keymap)

  (gadict-setup-syntax)

  (gadict-setup-paragraph)

  (gadict-setup-page)

(provide 'gadict)

;;; dict-mode.el ends here