;;; oni-shr.el --- Shr configuration                 -*- lexical-binding: t; -*-

;; Copyright (C) 2019  Tom Willemse

;; Author: Tom Willemse <tom@ryuslash.org>
;; Keywords: local
;; Version: 2021.1123.003019

;; 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:

;; Shr configuration.

;;; Code:

(require 'shr)

(defun oni-shr--colorize-remove-last-arg (args)
  "If ARGS has more than 3 items, remove the last one."
  (if (> (length args) 3)
      (butlast args)
    args))

(defun shr-tag-code (dom)
  "Render a <code> tag from DOM."
  (let ((shr-current-font 'default)
        (start (point)))
    (shr-generic dom)
    (add-face-text-property start (point) '(:background "#222222" :box (:line-width 3 :color "#222222")))))

(defun shr-tag-h1 (dom)
  "Render a <h1> tag from DOM."
  (shr-heading dom '(variable-pitch (:height 1.2 :weight bold :foreground "#65a854" :underline t))))

(defun shr-tag-h2 (dom)
  "Render a <h2> tag from DOM."
  (shr-heading dom '(variable-pitch (:height 1.1 :weight bold :foreground "#54a8a8"))))

(defun oni-shr--recolorize (orig-fun &rest args)
  "Do some custom colorization.

This should be used with ‘add-function’ with the ‘:around’
combinator. ORIG-FUN is the original function being wrapped, ARGS
are the arguments passed in to it."
  (let ((start (point)))
    (apply orig-fun args)
    (save-excursion
      (forward-line -1)
      (string-rectangle start (point) "  "))
    (add-face-text-property start (point) '(:background "#222222"))))

(advice-add #'shr-colorize-region
	        :filter-args #'oni-shr--colorize-remove-last-arg)
(add-function :around (symbol-function 'shr-tag-pre) #'oni-shr--recolorize)

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