bash-tpl

#!/usr/bin/env bash

#[[-------------------------------------------------------------------- Settings
set -o errexit   # abort on nonzero exitstatus
set -o nounset   # abort on unbound variable
set -o pipefail  # don't hide errors within pipes
# set -o xtrace
#]]


#[[-------------------------------------------------------------------- Script variables
readonly __script="$(basename "${BASH_SOURCE[0]}")"
readonly __dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
readonly __template_dir="${__dir}""/templates"
#]]


#[[-------------------------------------------------------------------- Utils
usage(){
  printf "%s [OPTIONS] -o|--output <output-file>\n\n" "${0}"
}

help_options(){
  printf "Options :\n"
  printf "  General options :\t\n"
  printf "    -h, --help                 Print this help text and exit\n"
  printf "    -o, --output FILENAME      Output in the specified file\n"
  printf "    -p, --parse PARSE          Add parsing method in main, see PARSE for all info\n"   
  printf "    -c, --color                Add util color script to the project and create a dir by default\n"
}

with_parse_option(){
  case "${1}" in 
    getopt)
      source="${__template_dir}/main-with-getopt-parsing"
      ;;
    getopts)
      source="${__template_dir}/main-with-getopts-parsing"
      ;;
    bash)
      source="${__template_dir}/main-with-bash-parsing"
      ;;
    *)
      printf "Parsing template %s unknown.\n" "${1}" 1>&2 exit 3
      source=""
      ;;
  esac

  echo "${source}"
}
#]]

#[[-------------------------------------------------------------------- Main
main() {
  # default values
  settings_template="$(< "${__template_dir}/settings-template")"
  main_template=""

  if [[ "${#}" -eq 0 ]]; then 
    usage && exit 1
  fi

  # BEGIN_PARAMETERS_LOOP
  while [[ $# -gt 0 ]]; do
    i="${1}"
    case ${i} in
      -p|--parse)
        parse="${2}"
        main_template="$(< "$(with_parse_option "${parse}")")"
        shift
        shift
        ;;
      -h|--help) 
        help_options && exit 0
        shift
        ;;
      -o|--output)
        output="${2}"
        shift
        shift
        ;;
      *) 
        printf "Unknown parameter passed: %s\n" "${1}" 1>&2
        usage
        exit 1
        ;;
    esac
  done
  # END_PARAMETERS_LOOP

  # check if output is set 
  if [[ ! -n "${output}" ]]; then
    printf "The output option -o|--output <filename> must be specified\n" 1>&2
  fi  
  
  # default main_template if nothing already set
  if [[ ! -n "${main_template}" ]]; then
    main_template="$(< "${__template_dir}/main-default")"
  fi

  # if file exist ask to override the file 
  if [[ -f "./${output}" ]]; then
      printf "%s exists.\n" "${output}"
      printf "Are you sure to override the file ? (y/n) "
      read answer
      case $answer in
      y)
        printf "File %s override.\n" "${output}" 
        ;;
      *)
        printf "Abort.\n" && exit 2 
        ;;
      esac
  fi

  # generate the file
  echo -e "#!/usr/bin/env bash\n" > "./${output}"  && \
    echo -e "${settings_template}\n" >> "./${output}"  && \
    echo -e "${main_template}\n" >> "./${output}" && \
    echo "File generated"

}
#]]

main "${@}"