elisp/erc-highlight-nicknames.el
2024-07-23 11:02:20 +12:00

177 lines
6.8 KiB
EmacsLisp

;;; erc-highlight-nicknames.el --- highlight nicknames in ERC -*- lexical-binding:t -*-
;; Copyright (C) 2007 André Riemann
;; Copyright (C) 2008-2014 Andy Stewart
;; Copyright (C) 2023 Jeremy Baxter
;; Author: André Riemann <andre.riemann@web.de>
;; Maintainer: Jeremy Baxter <jeremy@baxters.nz>
;; Created: 2007-09-25
;; Keywords: comm, faces
;; This file is not part of GNU Emacs.
;; erc-highlight-nicknames.el 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.
;;
;; erc-highlight-nicknames.el 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 erc-highlight-nicknames.el. If not, see
;; <https://www.gnu.org/licenses/>.
;;; Commentary:
;; This is a modified version of erc-highlight-nicknames.el from
;; <https://emacswiki.org/emacs/erc-highlight-nicknames.el>. It has been
;; extended to use the configured ERC colour palette, using the faces
;; with names beginning with `fg:erc-color-face'.
;;
;; Press: M-x customize-group RET erc-faces
;; for a list of these faces.
;; Originally authored by André Riemann in 2007 and updated from 2008-2014
;; by Andy Stewart. ERC face support was added by Jeremy Baxter in 2023.
;; To use erc-highlight-nicknames.el, put this in your init file:
;;
;; (require 'erc-highlight-nicknames)
;; (add-to-list 'erc-modules 'highlight-nicknames)
;; (erc-update-modules)
;; Press: M-x customize-face RET erc-highlight-nick-base-face RET
;; to customize the face that will be added before the color, if you want
;; for example all the nicks underlined.
;;; Change Log:
;; 2023-10-07 Jeremy Baxter
;; * Randomly pick a face out of a list of erc foreground faces
;; and use that to determine a user's nick face. This way
;; the possible nick colours can be customised by pressing
;; M-x customize-apropos-faces RET erc RET.
;; 2014-05-09
;; * Fixed `buffer-substring-no-properties' error with Emacs 24.4.50
;; 2008-12-07 Andy Stewart
;; * There was a bug that function `erc-highlight-nicknames' created
;; many faces for the same nickname. It would create a new one when
;; erc inserts text, and didn't care whether a face already existed
;; for this nickname.
;; Now I added a hash table `erc-highlight-face-table' to save the
;; face for a nickname. Faces are now only created, if the nickname
;; doesn't occur in the hash table.
;; 2007-12-24 andre-r
;; * bug fixed in invert-color where color code contained spaces instead
;; of leading zeros
;; 2007-12-12 andre-r
;; * erc-highlight-nick-base-face is by default empty now,
;; not inherited from `default'
;; * erc-button-add-face instead of put-text-property
;; * using `x-color-values' instead of `color-values' since XEmacs
;; seams to only know the former
;; 2007-12-12 andre-r
;; * built in XEmacs-compatible code for text properties by Dave Marquardt
;; (works both in Emacs and XEmacs)
;; * changed it a bit so that the face for the text property is derived
;; from another face (hopefully it still works with XEmacs)
;; * for that purpose created a new, customizable face
;; 2007-09-25 andre-r
;; * initial release
;;; Code:
(require 'erc)
(require 'erc-button)
(defconst erc-highlight-faces
'(fg:erc-color-face0
fg:erc-color-face1
fg:erc-color-face2
fg:erc-color-face3
fg:erc-color-face4
fg:erc-color-face5
fg:erc-color-face6
fg:erc-color-face7
fg:erc-color-face8
fg:erc-color-face9
fg:erc-color-face10
fg:erc-color-face11
fg:erc-color-face12
fg:erc-color-face13
fg:erc-color-face14
fg:erc-color-face15))
(defface erc-highlight-nick-base-face
'((t nil))
"Face used for highlighting nicknames before color is added."
:group 'erc-faces)
(defvar erc-highlight-face-table
(make-hash-table :test 'equal)
"Hash table containing unique ERC nickname faces.")
(defun hexcolor-luminance (color)
"Return the luminance of color COLOR. COLOR is a string \(e.g.
\"#ffaa00\", \"blue\"\) `color-values' accepts. Luminance is a
value of 0.299 red + 0.587 green + 0.114 blue and is always
between 0 and 255."
(let* ((values (x-color-values color))
(r (car values))
(g (car (cdr values)))
(b (car (cdr (cdr values)))))
(floor (+ (* 0.299 r) (* 0.587 g) (* 0.114 b)) 256)))
(defun invert-color (color)
"Return the inverted color of COLOR."
(let* ((values (x-color-values color))
(r (car values))
(g (car (cdr values)))
(b (car (cdr (cdr values)))))
(format "#%04x%04x%04x"
(- 65535 r) (- 65535 g) (- 65535 b))))
(defun erc-highlight-nicknames ()
"Highlight nicknames using a random face from `erc-highlight-faces'."
(with-syntax-table erc-button-syntax-table
(let (bounds bound-start bound-end word color new-nick-face)
(goto-char (point-min))
(while (re-search-forward "\\w+" nil t)
(setq bounds (bounds-of-thing-at-point 'word))
(setq bound-start (car bounds))
(setq bound-end (cdr bounds))
(when (and bound-start bound-end)
(setq word (buffer-substring-no-properties bound-start bound-end))
(when (erc-get-server-user word)
(setq new-nick-face (gethash word erc-highlight-face-table))
(unless new-nick-face
(setq new-nick-face
(nth (random (length erc-highlight-faces))
erc-highlight-faces))
(setq color (face-foreground new-nick-face))
(if (equal (cdr (assoc 'background-mode (frame-parameters))) 'dark)
;; if too dark for background
(when (< (hexcolor-luminance color) 85)
(setq color (invert-color color)))
;; if too bright for background
(when (> (hexcolor-luminance color) 170)
(setq color (invert-color color))))
(copy-face 'erc-highlight-nick-base-face new-nick-face)
(set-face-foreground new-nick-face color)
(puthash word new-nick-face erc-highlight-face-table))
(erc-button-add-face bound-start bound-end new-nick-face))
)
))))
(define-erc-module highlight-nicknames nil
"Search through the buffer for nicknames, and highlight them."
((add-hook 'erc-insert-modify-hook 'erc-highlight-nicknames t))
((remove-hook 'erc-insert-modify-hook 'erc-highlight-nicknames)))
(provide 'erc-highlight-nicknames)
;;; erc-highlight-nicknames.el ends here