;;; oni-css.el --- CSS configuration                 -*- lexical-binding: t; -*-

;; Copyright (C) 2019  Tom Willemse

;; Author: Tom Willemse <tom@ryuslash.org>
;; Keywords: local
;; Version: 2021.1201.134221
;; Package-Requires: (oni-company oni-hydra rainbow-mode oni-yasnippet)

;; 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 3 of the License, 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 this program.  If not, see <https://www.gnu.org/licenses/>.

;;; Commentary:

;; Configuration for `css-mode' and `scss-mode'.

;;; Code:

(require 'align)
(require 'css-mode)
(require 'hydra)
(require 'yasnippet)

(eval-when-compile
  (require 'compile)
  (require 'grep))

(defconst oni-css-root
  (file-name-directory
   (or load-file-name
       (buffer-file-name)))
  "The directory where ‘oni-css’ was loaded from.")

(defconst oni-css-snippets-dir
  (expand-file-name "snippets" oni-css-root)
  "The directory where ‘oni-css’ stores its snippets.")

(defun oni-css-property-important-p ()
  "Return whether or not the current property is important."
  (save-excursion
    (beginning-of-line)
    (re-search-forward "!important" (line-end-position) :noerror)))

(defun oni-css-add-important ()
  "Add an important flag to the property on the current line."
  (interactive)
  (unless (oni-css-property-important-p)
    (save-excursion
      (end-of-line)
      (when (re-search-backward ";" (line-beginning-position) :noerror)
        (insert " !important")))))

(defun oni-css-snippets-initialize ()
  "Initialize the snippets for ‘oni-css’."
  (when (boundp 'yas-snippet-dirs)
    (add-to-list 'yas-snippet-dirs oni-css-snippets-dir t))
  (yas-load-directory oni-css-snippets-dir))

(defun oni-css-remove-important ()
  "Remove the important flag from the property on the current line."
  (interactive)
  (when (oni-css-property-important-p)
    (save-excursion
      (end-of-line)
      (when (re-search-backward " !important" (line-beginning-position) :noerror)
        (replace-match "")))))

(defun oni-css-mode-init--toggle-important ()
  "Toggle the important flag on the property on the current line."
  (interactive)
  (if (oni-css-property-important-p)
      (oni-css-remove-important)
    (oni-css-add-important)))

(defun oni-css--auto-fill-mode ()
  "Enable ‘auto-fill-mode’ only for comments."
  (setq-local comment-auto-fill-only-comments t)
  (auto-fill-mode))

(defhydra css-mode-hydra (:color blue)
  ("!" oni-css-mode-init--toggle-important))

(setq css-indent-offset 2)

(add-hook 'css-mode-hook 'company-mode)
(add-hook 'css-mode-hook 'display-fill-column-indicator-mode)
(add-hook 'css-mode-hook 'electric-indent-local-mode)
(add-hook 'css-mode-hook 'electric-pair-local-mode)
(add-hook 'css-mode-hook 'oni-css--auto-fill-mode)
(add-hook 'css-mode-hook 'rainbow-mode)

(with-eval-after-load 'compile
  (let ((scss-error-regexp
         (rx (and bol
                  (zero-or-more space) "on line "
                  (group (one-or-more digit)) " of "
                  (group (one-or-more (or word punct (syntax symbol))))
                  eol))))

    (add-to-list 'compilation-error-regexp-alist
                 (list scss-error-regexp 2 1 nil 2 2))))

(define-key css-mode-map (kbd "C-c m") #'css-mode-hydra/body)

;; Align CSS files like so:

;;   body        { color: #ffffff;            }
;;   .some-class { background-color: #ffffff; }
;;   #some-id    { width: 200px;              }

;;   .some-more-class {
;;       color:            #ffffff;
;;       background-color: #ffffff;
;;       width:            200px;
;;   }

;; Keep these in order. They are each added to the _front_ of the
;; list and are applied in order. Changing their order will change
;; the results.
(add-to-list 'align-rules-list
             `(css-closing-brace
               (regexp . ,(rx (group (0+ whitespace)) "}" eol))
               (group . (1))
               (modes . '(scss-mode css-mode))))

(add-to-list 'align-rules-list
             `(css-colons
               (regexp . ,(rx bol
                              (0+ whitespace)
                              (1+ (any (?a . ?z) ?- ?$))
                              ":"
                              (group (0+ whitespace))
                              (0+ nonl)
                              ";"
                              eol))
               (group . (1))
               (modes . '(scss-mode css-mode))
               (repeat . t)))

(add-to-list 'align-rules-list
             `(css-opening-brace
               (regexp . ,(rx bol
                              (0+ whitespace)
                              (0+ (any ?# ?. ?, ?\s ?& ?: ?-
                                       (?a . ?z) (?A . ?Z) (?0 . ?9)))
                              (any (?a . ?z) (?A . ?Z) (?0 . ?9))
                              (group (0+ whitespace))
                              "{"
                              (0+ nonl)))
               (group . (1))
               (modes . '(scss-mode css-mode))))

;;;###autoload
(with-eval-after-load 'grep
  (add-to-list 'grep-files-aliases '("css" . "*.css *.less *.sass *.scss")))

(with-eval-after-load 'css-mode
  (with-eval-after-load 'yasnippet
    (oni-css-snippets-initialize)))

(provide 'oni-css)
;;; oni-css.el ends here