A python script to generate a range of colors based on a single color by adjusting the brightness and darkness of the color

color-range-generator.py

#!/usr/bin/env python3
import sys
import argparse

def hex_to_rgb(hex_color):
  if len(hex_color) != 7:
      raise Exception("Passed %s into hex_to_rgb(), needs to be in #87c95f format." % hex_color)
  rgb_hex = [hex_color[x:x+2] for x in [1, 3, 5]]
  rgb = [int(hex_value, 16) for hex_value in rgb_hex]

  return rgb

def rgb_to_hex(rgb):
  r,g,b = rgb
  return "#{0:02x}{1:02x}{2:02x}".format(r, g, b)

def get_steps_below(rgb, count):
  steps = [round((255 - num) / count) for num in rgb]

  return steps

def get_steps_above(rgb, count):
  steps = [round(num / count) for num in rgb]

  return steps

def get_range_above(rgb, count):
  steps = get_steps_above(rgb, count)
  new_rgbs = []
  last_rgb = rgb
  for _ in range(count):
    last_rgb = [max(0, color - steps[i]) for i, color in enumerate(last_rgb)]
    new_rgbs.append(last_rgb)

  return new_rgbs

def get_range_below(rgb, count):
  steps = get_steps_below(rgb, count)
  new_rgbs = []
  last_rgb = rgb
  for _ in range(count):
    last_rgb = [min(255, color + steps[i]) for i, color in enumerate(last_rgb)]
    new_rgbs.append(last_rgb)

  return new_rgbs


def get_range(rgb, count_above, count_below):
  above = []
  below = []
  if count_above:
    above = get_range_above(rgb, count_above)
  if count_below:
    below = get_range_below(rgb, count_below)
    below.reverse()

  return below + [rgb] + above

def main():
  parser = argparse.ArgumentParser()
  parser.add_argument('--hex', '-hx', required=True)
  parser.add_argument('--colors-darker', '-cd', default=0, type=int)
  parser.add_argument('--colors-lighter', '-cl', default=0, type=int)
  parser.add_argument('--css-var', '-var')
  parser.add_argument('--include-black-white', '-ibw', default=False, action='store_true')

  args = parser.parse_args(sys.argv[1:])

  hex = args.hex
  count_above = args.colors_darker
  count_below = args.colors_lighter
  css_var = args.css_var
  include_black_white = args.include_black_white

  if include_black_white:
    color_range = get_range(hex_to_rgb(hex), count_above, count_below)

    color_range[0] = [255, 255, 255]
    color_range[-1] = [0, 0, 0]
  else:
    color_range = get_range(hex_to_rgb(hex), count_above + 1, count_below + 1)
    color_range = color_range[1:-1]

  for rgb in color_range:
    r,g,b = rgb
    print(f'{r}, {g}, {b}      {rgb_to_hex(rgb)}')

  for rgb in color_range:
    r,g,b = rgb
    print(f'{r}, {g}, {b}')

  for rgb in color_range:
    r,g,b = rgb
    print(rgb_to_hex(rgb))

  print(".class {")
  for rgb in color_range:
    r,g,b = rgb
    print(f"  color: {rgb_to_hex(rgb)};")
  print("}")

  if css_var:
    for i, rgb in enumerate(color_range):
      r,g,b = rgb
      print(f"  --{css_var}-{i+1}00: {r}, {g}, {b}; /* {rgb_to_hex(rgb)} */")

    
    print("Dark mode")
    for i, rgb in enumerate(reversed(color_range)):
      r,g,b = rgb
      print(f"  --{css_var}-{i+1}00: {r}, {g}, {b}; /* {rgb_to_hex(rgb)} */")

if __name__ == '__main__':
  main()