#!/usr/bin/python3

# put this in .git/hooks and ensure it has exec permissions: "chmod +x prepare-commit-msg"
# use the following steps to use it globally
# - create ~/.git-templates
# - run the command: "git config --global init.templateDir '~/.git-templates'"
# - reinitialize existing git repos you wish to use this in: "git init"

import re, subprocess, sys

JIRA_ISSUE_URL = "https://smartvending.atlassian.net/browse/"
PREPEND_TICKET = True
APPEND_ISSUE_LINK = True

commit_file = sys.argv[1]
regex = re.compile("^([A-Z]+-[0-9]+)", re.IGNORECASE)

git_branch_name = subprocess.run(
    ["git", "branch", "--show-current"],
    stdout=subprocess.PIPE,
    encoding="utf-8",
)

match = regex.match(git_branch_name.stdout)

if match:
    ticket = match.group()
    ticket_url = f"{JIRA_ISSUE_URL}{ticket}"

    with open(commit_file, "r+") as f:
        contents = f.read().strip()

        if PREPEND_TICKET and not contents.startswith(ticket):
            contents = f"{ticket}: {contents}"

        if APPEND_ISSUE_LINK:
            contents = f"{contents}\n\n{ticket_url}"

        f.seek(0)
        f.write(contents)