#!/usr/bin/env python
import os
import sys
from string import Template

import requests

def main(arg=None):
    repo = os.getenv("HELLO_REPO")
    assert repo is not None, "No repo configured!"

    templates = []
    for t in requests.get(repo).json():
        templates.append(t['name'])

    if arg is None:
        return "\n".join(templates)

    if arg in templates:
        url = "{0}/{1}".format(repo.rstrip("/"), arg)
        template = Template(requests.get(url).text)
        return template.substitute(**os.environ)
    else:
        error = "Template for {0} not found".format(arg)
        raise Exception(error)


if __name__ == '__main__':
    arg = None
    if len(sys.argv) > 1:
        arg = sys.argv[1]

    print(main(arg))