sync_templates_and_ci

#!/bin/bash

readonly caskroom_online='https://github.com/caskroom'
readonly caskroom_repos_dir="$(mktemp -d)"
readonly main_repo_dir="$(mktemp -d)" # From where files will be copied
readonly caskroom_repos=(homebrew-versions homebrew-fonts homebrew-eid homebrew-drivers) # homebrew-cask is absent since it's the repo all the others are compared against

function message {
  echo "${1}"
}

function get_main_repo {
  curl --silent --location "${caskroom_online}/homebrew-cask/archive/master.zip" | ditto -xk - "${main_repo_dir}"
  mv "${main_repo_dir}/homebrew-cask-master/"{,.[^.]}* "${main_repo_dir}"
  rmdir "${main_repo_dir}/homebrew-cask-master"
}

function get_repo {
  local repo_name repo_dir

  repo_name="${1}"
  repo_dir="${caskroom_repos_dir}/${repo_name}"

  cd "${caskroom_repos_dir}" || exit 1
  message "Cloning ${repo_name}…"
  git clone "${caskroom_online}/${repo_name}.git" --quiet
  cd "${repo_dir}" || exit 1
}

function copy_templates_and_ci {
  local repo_name

  repo_name="${1}"
  rsync --archive --delete "${main_repo_dir}"/{.editorconfig,.gitattributes,.github,.gitignore,.travis.yml,ci,CODE_OF_CONDUCT.md} '.'
  /usr/bin/sed -i '' -E "s:homebrew-cask/(pulls|issues):${repo_name}/\1:" '.github/PULL_REQUEST_TEMPLATE.md' # PULL_REQUEST_TEMPLATE has repo-specific links
}

function push_changes {
  local is_repo_changed

  is_repo_changed="$(git status --porcelain --ignore-submodules=dirty 2> /dev/null)"
  if [[ -n "${is_repo_changed}" ]]; then
    git add --all # Stage everything so 'git diff' does not miss aything (like new paths)
    for modified_path in $(git diff --name-only --staged); do
      echo -n "Detected changes to ${modified_path}. "
      git commit "${modified_path}" --message "$(basename "${modified_path}"): update to match main repo" --quiet
    done

    echo 'Updating…'
    git push origin master --quiet
  fi
}

get_main_repo
for repo in "${caskroom_repos[@]}"; do
  get_repo "${repo}"
  copy_templates_and_ci "${repo}"
  push_changes
done