#! /usr/bin/python3
# amend HEAD commit to contain acab in its hash, it does so by repeatedly
# amending the commit with a new date.

import argparse
import subprocess
import sys
import time

parser = argparse.ArgumentParser()
parser.add_argument('--start', type=str, default='commit', help='now or commit')
parser.add_argument('--prefix', action='store_true')
parser.add_argument('--suffix', action='store_true')
parser.add_argument('-q', '--quiet', action='store_true')
args = parser.parse_args()

if args.start == 'commit':
    p = subprocess.run(['git', 'show', '--format=format:%at'], capture_output=True)
    timestamp = int(p.stdout[: p.stdout.index(b'\n')])
elif args.start == 'now':
    timestamp = int(time.time())
else:
    sys.stderr('unknown value for --start')
    sys.exit(1)

t0 = time.time()
counter = 0
direction = -1
while True:
    counter += 1
    timestamp += direction
    if counter % 3600 == 0:
        # don't move more than one hour in the past, going back to initial time
        # will give new commit hashes as the commit date (not author date) will
        # be different.
        direction = - direction
    if not args.quiet:
        print(
            '%5d - %s - [%s:%02d]'
            % (
                counter,
                time.strftime('%Y-%m-%d %H:%M:%S', time.localtime(timestamp)),
                int((time.time() - t0) // 60),
                int((time.time() - t0) % 60),
            ),
            end='\r',
        )
    p = subprocess.run(
        [
            'git',
            'commit',
            '--no-verify',
            '--amend',
            '--no-edit',
            '--date=%s' % time.strftime('%Y-%m-%d %H:%M:%S', time.localtime(timestamp)),
        ],
        capture_output=True,
    )
    p = subprocess.run(['git', 'rev-parse', 'HEAD'], capture_output=True)
    if args.prefix and not p.stdout.startswith(b'acab'):
        continue
    if args.suffix and not p.stdout.strip().endswith(b'acab'):
        continue
    if b'acab' in p.stdout:
        break

if not args.quiet:
    print('\ngot %s 🔥🚓' % p.stdout.decode().strip())