#!/usr/bin/env bash

# tmux requires unrecognized OSC sequences to be wrapped with DCS tmux;
# <sequence> ST, and for all ESCs in <sequence> to be replaced with ESC ESC. It
# only accepts ESC backslash for ST.
function print_osc() {
    if [[ $TERM == screen* || $TERM == tmux* ]] ; then
        printf "\033Ptmux;\033\033]"
    else
        printf "\033]"
    fi
}

# More of the tmux workaround described above.
function print_st() {
    if [[ $TERM == screen* || $TERM == tmux* ]] ; then
        printf "\a\033\\"
    else
        printf "\a"
    fi
}

function show_help() {
    echo "Usage:" 1>& 2
    echo "   $(basename $0) set Fn Label" 1>& 2
    echo "     Where n is a value from 1 to 20" 1>& 2
    echo "   $(basename $0) set status Label" 1>& 2
    echo "     Sets the touch bar status button's label" 1>& 2
    echo "   $(basename $0) push [name]" 1>& 2
    echo "     Saves the current labels with an optional name. Resets labels to their default value, unless name begins with a "." character." 1>& 2
    echo "   $(basename $0) pop [name]" 1>& 2
    echo "     If name is given, all key labels up to and including the one with the matching name are popped." 1>& 2
    echo "" 1>& 2
    echo "Example:" 1>& 2
    echo "#!/usr/bin/env bash" 1>& 2
    echo "# Wrapper script for mc that sets function key labels" 1>& 2
    echo "NAME=mc_\$RANDOM" 1>& 2
    echo "# Save existing labels" 1>& 2
    echo "$(basename $0) push \$NAME" 1>& 2
    echo "$(basename $0) set F1 Help" 1>& 2
    echo "$(basename $0) set F2 Menu" 1>& 2
    echo "$(basename $0) set F3 View" 1>& 2
    echo "$(basename $0) set F4 Edit" 1>& 2
    echo "$(basename $0) set F5 Copy" 1>& 2
    echo "$(basename $0) set F6 Move" 1>& 2
    echo "$(basename $0) set F7 Mkdir" 1>& 2
    echo "$(basename $0) set F8 Del" 1>& 2
    echo "$(basename $0) set F9 Menu" 1>& 2
    echo "$(basename $0) set F10 Quit" 1>& 2
    echo "$(basename $0) set F11 Menu" 1>& 2
    echo "$(basename $0) set F13 View" 1>& 2
    echo "$(basename $0) set F14 Edit" 1>& 2
    echo "$(basename $0) set F15 Copy" 1>& 2
    echo "$(basename $0) set F16 Move" 1>& 2
    echo "$(basename $0) set F17 Find" 1>& 2
    echo "mc" 1>& 2
    echo "# Restore labels to their previous state" 1>& 2
    echo "$(basename $0) pop \$NAME" 1>& 2
}

## Main
if [[ $# == 0 ]]
then
  show_help
  exit 1
fi

if [[ $1 == set ]]
then
  if [[ $# != 3 ]]
  then
    show_help
    exit 1
  fi
  print_osc
  printf "1337;SetKeyLabel=%s=%s" "$2" "$3"
  print_st
elif [[ $1 == push ]]
then
  if [[ $# == 1 ]]
  then
    print_osc
    printf "1337;PushKeyLabels"
    print_st
  elif [[ $# == 2 ]]
  then
    if [[ $2 == "" ]]
    then
      echo "Name must not be empty" 1>& 2
      exit 1
    fi
    print_osc
    printf "1337;PushKeyLabels=%s" "$2"
    print_st
  else
    show_help
    exit 1
  fi
elif [[ $1 == pop ]]
then
  if [[ $# == 1 ]]
  then
    print_osc
    printf "1337;PopKeyLabels"
    print_st
  elif [[ $# == 2 ]]
  then
    if [[ $2 == "" ]]
    then
      echo "Name must not be empty" 1>& 2
      exit 1
    fi
    print_osc
    printf "1337;PopKeyLabels=%s" "$2"
    print_st
  else
    show_help
    exit 1
  fi
else
  show_help
  exit 1
fi