#!/usr/bin/env python3

import re
import os
import requests
import secrets
import sys


def die(s):
    print(s, file=sys.stderr)
    sys.exit(1)


gitlab_token = os.getenv('GITLAB_TOKEN')
if gitlab_token is None:
    die("GITLAB_TOKEN must be set in the environment")

if len(sys.argv) < 4:
    die("Usage: {} GITLAB_INSTANCE HOOK_URL_BASE NAMESPACE/REPO\n\nExample: {} gitlab.example.com https://bot.example.com/bebot stuff/myrepo")

gitlab_instance = sys.argv[1]
hook_url = f"{sys.argv[2]}/hooks/gitlab"
repo_name = sys.argv[3]

gl_base = 'https://{}/api/v4/projects/{}/hooks'.format(
    gitlab_instance,
    re.sub('/', '%2F', repo_name)
)
headers = {
    'authorization': 'Bearer {}'.format(gitlab_token),
}
payload = {
    "issues_events": True,
    "merge_requests_events": True,
    "pipeline_events": True,
    "push_events": True,
    "tag_push_events": True,
}

resp = requests.get(gl_base, headers=headers)
if resp.status_code != 200:
    resp.raise_for_status()
existing = resp.json()

for hook in existing:
    if hook['url'] == hook_url:
        upd_url = '{}/{}'.format(gl_base, hook['id'])
        resp = requests.put(upd_url, headers=headers, json=payload)
        print("Updated existing hook for {}".format(repo_name))
        sys.exit(0)

token = secrets.token_urlsafe(32)
payload["url"] = hook_url
payload["token"] = token
resp = requests.post(gl_base, headers=headers, json=payload)
resp.raise_for_status()
print('  "{}/{}":'.format(gitlab_instance, repo_name))
print('    token: "{}"'.format(token))