center

#!/usr/bin/env python3
import click
import sys
import shutil


@click.command()
@click.argument('input', required=False, type=click.File('r'))
@click.argument('output', required=False, type=click.File('w'))
@click.option('-l', '--length', help='maximum line length [default:current terminal size]', type=click.INT)
@click.option('-i', '--indent', help='indent text instead of centering', is_flag=True)
def cli(input, output, length, indent):
    """Simple, pipeable tool for centering text"""
    columns = shutil.get_terminal_size()[0]
    source = input.readlines() if input else sys.stdin
    if indent:
        source = list(source)
        max_line = len(sorted(source, key=len, reverse=True)[0])
        indent_size = int((columns - max_line) / 2)
        format_ = '{}{{}}\n'.format(indent_size * ' ')
    else:
        format_ = '{{:^{}}}\n'.format(length or int(columns))
    for line in source:
        text = format_.format(line.strip())
        if output:
            output.write(text)
        else:
            sys.stdout.write(text)

if __name__ == "__main__":
    cli()