#!/usr/bin/env python3

# Use:
# swh-revhash 'tree 4b825dc642cb6eb9a060e54bf8d69288fbee4904\nparent 22c0fa5195a53f2e733ec75a9b6e9d1624a8b771\nauthor seanius <seanius@3187e211-bb14-4c82-9596-0b59d67cd7f4> 1138341044 +0000\ncommitter seanius <seanius@3187e211-bb14-4c82-9596-0b59d67cd7f4> 1138341044 +0000\n\nmaking dir structure...\n'  # noqa
# output: 17a631d474f49bbebfdf3d885dcde470d7faafd7

# To compare with git:
# git-revhash 'tree 4b825dc642cb6eb9a060e54bf8d69288fbee4904\nparent 22c0fa5195a53f2e733ec75a9b6e9d1624a8b771\nauthor seanius <seanius@3187e211-bb14-4c82-9596-0b59d67cd7f4> 1138341044 +0000\ncommitter seanius <seanius@3187e211-bb14-4c82-9596-0b59d67cd7f4> 1138341044 +0000\n\nmaking dir structure...\n'   # noqa
# output: 17a631d474f49bbebfdf3d885dcde470d7faafd7


import sys

from swh.model import identifiers, hashutil


def revhash(revision_raw):
    """Compute the revision hash.

    """
    # HACK: string have somehow their \n expanded to \\n
    if b'\\n' in revision_raw:
        revision_raw = revision_raw.replace(b'\\n', b'\n')

    h = hashutil.hash_git_data(revision_raw, 'commit')
    return identifiers.identifier_to_str(h)


if __name__ == '__main__':
    revision_raw = sys.argv[1].encode('utf-8')
    print(revhash(revision_raw))