#!/usr/bin/env bash
#
# backup all tracked files
#
# @params
# Globals
#   ${mydir}: current dir of the script
#   ${backup_type}: types of backup, individual or all
#   ${selected_files}: selected files to backup
#   ${action_command}: actions to run, cp|mv
# Arguments
#   -h|--help: show help message and exit
#   -s|--select: select individual files through fzf and backup
#   -p PATH|--path PATH: pass in path and backup
#   -m|--move: use mv to backup instead of cp

set -e
set -f

mydir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
source "${mydir}"/../helper/set_variable.sh
source "${mydir}"/../helper/git_query.sh

function usage() {
  echo -e "Usage: dotbare fbackup [-h] [-m] [-s] [-p PATH] ...\n"
  echo -e "Backup files to ${DOTBARE_BACKUP}."
  echo -e "This is useful when untracking files or migrating to new machines.\n"
  echo -e "Default: backup all tracked files using cp command to ${DOTBARE_BACKUP} directory.\n"
  echo -e "optional arguments:"
  echo -e "  -h, --help\t\tshow this help message and exit."
  echo -e "  -s, --select\t\tlist all tracked files and only backup the selected files."
  echo -e "  -p PATH, --path PATH\tsepcify path of files to backup."
  echo -e "  -m, --move\t\tuse 'mv' instead of the default 'cp' command to backup."
}

#######################################
# backup passed in files while preserving directory info
# Arguments:
#   $1: files to backup, seperate by \n
#   $2: action command (cp|mv)
#######################################
function dotbare_backup() {
  local selected_files="$1"
  local action_command="${2:-cp}"
  while IFS= read -r line; do
    dir_name=$(dirname "${line}")
    [[ ! -d "${DOTBARE_BACKUP}/${dir_name}" ]] && mkdir -p "${DOTBARE_BACKUP}/${dir_name}"
    [[ "${action_command}" == "cp" ]] \
      && cp -av "${line}" "${DOTBARE_BACKUP}/${line}" \
      && continue
    # Purposly didn't use the -v flag because in finit, error message were
    # directed to /dev/null but the cp/mv info will still be printed, causing confusion.
    [[ "${action_command}" == "mv" ]] \
      && mv "${line}" "${DOTBARE_BACKUP}/${line}" \
      && echo "${line} -> ${DOTBARE_BACKUP}/${line}"
  done <<< "${selected_files}"
  exit 0
}

backup_type="all"
action_command='cp'
selected_files=""

while [[ "$#" -gt 0 ]]; do
  case "$1" in
    -s|--select)
      backup_type="select"
      shift
      ;;
    -p|--path)
      [[ -z "$2" ]] && echo "Invalid option: $1" >&2 && usage && exit 1
      selected_files="$2"
      shift
      shift
      ;;
    -m|--move)
      action_command="mv"
      shift
      ;;
    -h|--help)
      usage
      exit 0
      ;;
    *)
      echo "Invalid option: $1" >&2
      usage
      exit 1
      ;;
  esac
done


[[ -n "${selected_files}" ]] && dotbare_backup "${selected_files}" "${action_command}"

cd "${DOTBARE_TREE}"
if [[ "${backup_type}" == 'select' ]]; then
  selected_files=$(get_git_file "select files to backup" "raw")
else
  selected_files=$(git --git-dir="${DOTBARE_DIR}" --work-tree="${DOTBARE_TREE}" \
    ls-files --full-name --directory "${DOTBARE_TREE}")
fi

[[ -z "${selected_files}" ]] && exit 1
dotbare_backup "${selected_files}" "${action_command}"