ASCII progress bar generator (useful for CLI apps & tiling WM widgets)

ascii_progress.py

"""
Author: Andrew Dunai <andrew@dun.ai>
Original code & symbol collection: Changaco <https://changaco.oy.lc/unicode-progress-bars/>

Example GIF: https://habrastorage.org/files/c28/461/630/c28461630bdf46d18be788352a2ef468.gif
Example screenshot: http://public.dun.ai/public/screenshots/148456797191.jpg (left & right widget)

>>> print progress(1, 100, 42, 10)
⎹████▂▁▁▁▁▁⎸
>>> print progress(1, 10, 3, 20, style=1)
⎹⣿⣿⣿⣿⣦⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⎸
>>> print progress(50, 100, 80, 10, style=16)
⎹██████▏▏▏▏⎸
>>> print progress(1, 5, 4.2, 15, style=4, before='<', after='>')
<■■■■■■■■■■■■□□□>
>>> print progress(0.1, 1.0, 0.42, 10, style=6, before='[', after=']')
[■■■▩□□□□□□]
>>> print progress(1, 100, 34, 5, style=6, before='Battery: ', after='')
Battery: ■▩□□□
"""

bar_styles = [
    u'▁▂▃▄▅▆▇█',
    u'⣀⣄⣤⣦⣶⣷⣿',
    u'⣀⣄⣆⣇⣧⣷⣿',
    u'○◔◐◕⬤',
    u'□◱◧▣■',
    u'□◱▨▩■',
    u'□▨▩■',
    u'□◱▥▦■',
    u'░▒▓█',
    u'░█',
    u'⬜⬛',
    u'▱▰',
    u'▭◼',
    u'▯▮',
    u'◯⬤',
    u'⚪⚫',
    u'▏▎▍▌▋▊▉█'
]


def progress(min, max, current, width, style=0, before=u'⎹', after=u'⎸'):
    """
    :param min: minimum (starting) bar value
    :param max: maximum (ending) bar value
    :param current: current bar progress value
    :param width: size of resulting bar in characters (excluding `before` and `after`)
    :param style: index of palette, `0 <= style < len(bar_styles)`
    :param before: string to prepend to result
    :param after: string  to append to result
    :return: string of length `width + len(before) + len(after)`
    """
    style = bar_styles[style]
    q_max = len(style) * width
    ratio = float(current - min) / (max - min)
    q_current = int(ratio * q_max)
    return before + ''.join([
        style[-1]
        if x <= q_current
        else style[q_current - x]
        if x - q_current < len(style)
        else style[0]
        for x
        in [y * len(style) for y in xrange(1, width + 1)]
    ]) + after