add jira ticket from git branch as prepare-commit-msg git hook

prepare-commit-msg

#!/usr/bin/env bash

## Automatically append jira issue ticket to every commit if found in the git branch name and not already in the commit message
## Ref: https://community.atlassian.com/t5/Bitbucket-questions/automatically-append-JIRA-issue-ID-into-commit-message/qaq-p/605991
## https://stackoverflow.com/a/67647814/93966

BRANCH_NAME=$(git rev-parse --abbrev-ref HEAD 2>/dev/null)

# It will copy the commit string from ".git/COMMIT_EDITMSG"
COMMIT_MESSAGE=$1
COMMIT_MESSAGE=`head -n1 $COMMIT_MESSAGE`

# Ensure BRANCH_NAME is not empty and is not in a detached HEAD state (i.e. rebase).
# SKIP_PREPARE_COMMIT_MSG may be used as an escape hatch to disable this hook,
# while still allowing other githooks to run.
if [ ! -z "$BRANCH_NAME" ] && [ "$BRANCH_NAME" != "HEAD" ] && [ "$SKIP_PREPARE_COMMIT_MSG" != 1 ]; then
    PREFIX_PATTERN='[A-Z0-9]{2,10}-[0-9]{1,7}'

    [[ $BRANCH_NAME =~ $PREFIX_PATTERN ]]

    PREFIX=${BASH_REMATCH[0]}
    PREFIX_IN_COMMIT=$(echo $COMMIT_MESSAGE | grep -c "$PREFIX")

    # echo "COMMIT_MESSAGE: $COMMIT_MESSAGE"
    # echo "PREFIX: $PREFIX"
    # echo "PREFIX_IN_COMMIT: $PREFIX_IN_COMMIT"

    # Ensure PREFIX exists in BRANCH_NAME and is not already present in the commit message
    if [[ -n "$PREFIX" ]] && ! [[ $PREFIX_IN_COMMIT -ge 1 ]]; then
        sed -i '' -e "1s/$/\n\n\[$PREFIX\]/" $1
    fi
fi