#!/usr/bin/env python

from subprocess import check_output
import argparse
import sys

parser = argparse.ArgumentParser()
parser.add_argument("ROOT_HASH", help="root tree for the search")
parser.add_argument("PATH_ITEM", help="path component", nargs='*')
opts = parser.parse_args()
tree_hash = opts.ROOT_HASH
path = opts.PATH_ITEM

while path:
    target_name = path[0]
    subtree_items = check_output(['git', 'ls-tree', '-z', tree_hash])
    target_hash = None
    for entry in subtree_items.split('\0'):
        if not entry:
            break
        info, name = entry.split('\t', 1)
        if name == target_name:
            _, _, target_hash = info.split(' ')
            break
    if not target_hash:
        print >> sys.stderr, "Can't find %r in %s" % (target_name, tree_hash)
        break
    tree_hash = target_hash
    path = path[1:]

if path:
    sys.exit(1)

print tree_hash