#!/bin/bash

function get_sed () {
  OS=$(uname  -s)
  if [ "${OS}" == "Linux" ]; then
    SED=$(command -v sed)
  else
    SED=$(command -v gsed)
  fi
  if [ -z "${SED}" ]; then
    echo ">> GNU 'sed' was not found on the system."
    echo ">> Please install it"
    exit 1
  fi
  echo "${SED}"
}

function not_include_ticket () {
  set -o pipefail
  if $(cat "$*" | grep -q "^JIRA: "); then
    return 1
  fi
  return 0
}

function get_branch_name () {
    echo "$(git branch --show-current)"
}

# Function to extract the ticket number:
# Ex: AVXSRE-12324-toto -> AVXSRE-1234
#     AVXSRE-12134/titi -> AVXSRE-1234
function clean_branch_name () {
  echo "$1" | grep -E -o '[A-Z][A-Z0-9]+-[0-9]+'
}

function add_jira_ref () {
    # hook arguments
    COMMIT_MSG_FILE=$1
    # Possible values are none (git commit), message (git commit -m <msg>), template, merge, squash, or commit
    COMMIT_SOURCE=$2

    SED="$(get_sed)"
    BRANCH="$(get_branch_name)"
    CLEAN_BRANCH="$(clean_branch_name $BRANCH)"

    # check branch name isn’t empty (typical e.g. during rebase)
    if not_include_ticket "${COMMIT_MSG_FILE}" && [ -n "${CLEAN_BRANCH}" ]; then
      # check that this is a "message": if a -m or -F option was given
      if [ "${COMMIT_SOURCE}" == "message" ]; then
        echo >> "${COMMIT_MSG_FILE}"
        echo "JIRA: ${CLEAN_BRANCH}" >> "${COMMIT_MSG_FILE}"
        return 0
      fi

      # check that this is a "commit"
      if [ -z "${COMMIT_SOURCE}" ]; then
        ${SED} -i "1s@^@\n\nJIRA: ${CLEAN_BRANCH}@" "${COMMIT_MSG_FILE}"
        return 0
      fi

      # check that this is an "amend"
      if [ "${COMMIT_SOURCE}" == "commit" ]; then
        ${SED} -i "2s@^@\n\nJIRA: ${CLEAN_BRANCH}\n@" "${COMMIT_MSG_FILE}"
        return 0
      fi
    fi
}