#!/bin/sh

# This file defines track - a minimalist data tracker

# Copyright (C) 2018 tomasino@sdf.org

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.

#-----------------------------------------------------------------------

version="v0.0.1"

show_help () {
  cat > /dev/stdout << END
track [options] [metric] [value]

USAGE:
  track weight 150            Log 150lbs for today's weight
  track -n 10 calories        Show last 10 days calorie values
  track mood                  Show last value logged for mood

OPTIONS:
  -a                          Show all values of metric
  -n N                        Show N values of metric
  -x                          Remove metric file
  -h                          Show this help
  -v                          Show current version info
  -d                          Debug mode

END
}

arg_metric=""
arg_value=""
flag_options="hvdan:x:s"
flag_debug=0
flag_help=0
flag_listall=0
flag_listnum=0
flag_remove=0
flag_version=0
flag_shortlist=0

die () {
  msg="$1"
  code="$2"
  # exit code defaults to 1
  if printf "%s" "$code" | grep -q '^[0-9]+$'; then
    code=1
  fi
  # output message to stdout or stderr based on code
  if [ ! -z "$msg" ]; then
    if [ "$code" -eq 0 ]; then
      printf "%s\\n" "$msg"
    else
      printf "%s\\n" "$msg" >&2
    fi
  fi
  exit "$code"
}

parse_input () {
  if ! parsed=$(getopt $flag_options "$@"); then
    die "Invalid input" 2
  fi

  eval set -- "$parsed"

  while true; do
    case "$1" in
      -h)
        flag_help=1
        shift
        ;;
      -v)
        flag_version=1
        shift
        ;;
      -d)
        flag_debug=1
        shift
        ;;
      -a)
        flag_listall=1
        shift
        ;;
      -n)
        flag_listnum=1
        shift
        arg_listnum="$1"
        shift
        ;;
      -x)
        flag_remove=1
        shift
        arg_remove="$1"
        shift
        ;;
      -s)
        flag_shortlist=1
        shift
        ;;
      --)
        shift
        break
        ;;
      *)
        die "Internal error: $1" 3
        ;;
    esac
  done

  for arg in "$@"; do
    argc=$(printf "%s" "$arg" | tr '[:upper:]' '[:lower:]')
    if [ "$arg_metric" = "" ]; then
      arg_metric="$argc"
    elif [ "$arg_value" = "" ]; then
      arg_value="$argc"
    fi
  done
}

main () {
  parse_input "$@"

  if [ $flag_shortlist -gt 0 ]; then
    out="-v -h -d -a -n -x"
    die "${out}" 0
  fi

  if [ $flag_version -gt 0 ]; then
    printf "%s\\n" "$version"
  fi

  if [ $flag_help -gt 0 ]; then
    show_help
  fi

  if [ $flag_debug -gt 0 ]; then
    # set -x
    printf "arg_metric=%s\n" "$arg_metric"
    printf "arg_value=%s\n" "$arg_value"
    printf "arg_listnum=%s\n" "$arg_listnum"
    printf "arg_remove=%s\n" "$arg_remove"

    printf "flag_debug=%s\n" "$flag_debug"
    printf "flag_help=%s\n" "$flag_help"
    printf "flag_listall=%s\n" "$flag_listall"
    printf "flag_listnum=%s\n" "$flag_listnum"
    printf "flag_remove=%s\n" "$flag_remove"
    printf "flag_version=%s\n" "$flag_version"
    printf "flag_shortlist=%s\n" "$flag_shortlist"
  fi


}

main "$@"