Indents and colorizes lines based on the number of levels of preprocessor if statements

endif_colors.py

# Copyright 2021 Lyuma
#
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# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
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# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
# 
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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# SOFTWARE.

import sys
import re
re_preprocessor = re.compile(r'^\s*#')
re_if = re.compile(r'^\s*#\s*if')
re_else = re.compile(r'^\s*#\s*el[is][ef]')
re_endif = re.compile(r'^\s*#\s*endif')

indentlevel=0
boldcolor = '\x1b[0;1m'
#colorlist=['\x1b[0;32m', '\x1b[0;33m', '\x1b[0;90m', '\x1b0;1;31m', '\x1b0;1;34m', '\x1b0;1;33m']
colorlist=['\x1b[0;37m', '\x1b[1;30m', '\x1b[0;34m', '\x1b[0;33m', '\x1b[0;35m', '\x1b[0;36m', '\x1b[0;37m', '\x1b[0;32m', '\x1b[0;31m']
isatty = True # sys.stdout.isatty()
linenum = 0
for x in sys.stdin.readlines():
    linenum += 1
    prefix = colorlist[indentlevel]
    if re_preprocessor.match(x):
        prefix = boldcolor
    if not isatty:
        prefix = ''
    if re_endif.match(x) or re_else.match(x):
        indentlevel -= 1
    if indentlevel < 0:
        prefix = '\x1b[0;1;7;31m*** ERROR ***'
    sys.stdout.write(('% 7d ' % (linenum,)) + ('\t' * indentlevel) + boldcolor + '|' + prefix + x)
    if re_if.match(x) or re_else.match(x):
        indentlevel += 1