src/collecty/util.py

   1 #!/usr/bin/python3
   2 ###############################################################################
   3 #                                                                             #
   4 # collecty - A system statistics collection daemon for IPFire                 #
   5 # Copyright (C) 2015 IPFire development team                                  #
   6 #                                                                             #
   7 # This program is free software: you can redistribute it and/or modify        #
   8 # it under the terms of the GNU General Public License as published by        #
   9 # the Free Software Foundation, either version 3 of the License, or           #
  10 # (at your option) any later version.                                         #
  11 #                                                                             #
  12 # This program is distributed in the hope that it will be useful,             #
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of              #
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the               #
  15 # GNU General Public License for more details.                                #
  16 #                                                                             #
  17 # You should have received a copy of the GNU General Public License           #
  18 # along with this program.  If not, see <http://www.gnu.org/licenses/>.       #
  19 #                                                                             #
  20 ###############################################################################
  21
  22 def __add_colour(colour, amount):
  23         colour = colour.strip("#")
  24
  25         colour = (
  26                 int(colour[0:2], 16),
  27                 int(colour[2:4], 16),
  28                 int(colour[4:6], 16),
  29         )
  30
  31         # Scale the colour
  32         colour = (e + amount for e in colour)
  33         colour = (max(e, 0) for e in colour)
  34         colour = (min(e, 255) for e in colour)
  35
  36         return "#%02x%02x%02x" % tuple(colour)
  37
  38 def lighten(colour, scale=0.1):
  39         """
  40                 Takes a hexadecimal colour code
  41                 and brightens the colour.
  42         """
  43         return __add_colour(colour, 0xff * scale)
  44
  45 def darken(colour, scale=0.1):
  46         """
  47                 Takes a hexadecimal colour code
  48                 and darkens the colour.
  49         """
  50         return __add_colour(colour, 0xff * -scale)