import os.path
import subprocess
from jinja2 import Environment, PackageLoader, select_autoescape

def shortgitrev() -> str:
    return subprocess.check_output(['git', 'rev-parse', '--short', 'HEAD']).decode('ascii').strip()

def gengitrev():
    env = Environment(
        loader=PackageLoader("gen_git_rev"),
        autoescape=select_autoescape()
        )

    template = env.get_template("git_revision.h")

    stream = template.stream(hash=shortgitrev())

    # Check if in Project root
    print(os.path.abspath("Core/Inc"))
    if(os.path.exists(os.path.abspath("Core/Inc"))):
        print("Core/Inc dir found, generating file...")
        with open(os.path.abspath("Core/Inc/git_rev.h"), 'w') as fp:
            stream.dump(fp)
    else:
        print("ERROR: Run this script from the Project root!")
        exit(-1)


if __name__ == "__main__":
    gengitrev()