#!/usr/bin/env python3
'''
git blame a file repeatedly, showing the blame at previous versions
'''

import re
import subprocess
import sys

def main():
	commit = 'HEAD'
	while True:
		blame = subprocess.Popen(['git-blame', *sys.argv[1:], commit],
				stdout=subprocess.PIPE)
		try:
			blame = subprocess.Popen(['delta', '--color-only'],
					stdin=blame.stdout, stdout=subprocess.PIPE)
		except FileNotFoundError:
			pass
		fzf = subprocess.run(['fzf', '--no-sort', '--tiebreak=index', '--reverse', '--ansi'],
				stdin=blame.stdout, stdout=subprocess.PIPE, text=True)
		blame.wait()
		if fzf.returncode in (1, 130): # no match, esc
			return
		commit = re.search('[0-9a-f]{7,40}', fzf.stdout).group(0) + '^'

if __name__ == '__main__':
	main()