#!/usr/bin/env bash

# This file is part of I38.

# I38 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.

# I38 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 I38. If not, see <https://www.gnu.org/licenses/>.


# This script is a modified version of i3-keyboard-layout.
# Originally Copyright (c) 2018 Sergio Gil.
# https://github.com/porras/i3-keyboard-layout
# The original work was released under the MIT license.


set -e

# Detect if we're on Wayland or X11
if [[ -n "${WAYLAND_DISPLAY}" ]]; then
    usingWayland=true
else
    usingWayland=false
fi

get_kbdlayout() {
  if [[ "$usingWayland" == "true" ]]; then
    # Sway: Get keyboard layout from input devices
    # This gets the xkb_active_layout_name from the first keyboard
    layout=$(swaymsg -t get_inputs | jq -r '.[] | select(.type=="keyboard") | .xkb_active_layout_name' | head -n 1)
    echo "$layout"
  else
    # i3: Use setxkbmap
    layout=$(setxkbmap -query | grep -oP 'layout:\s*\K([\w,]+)')
    variant=$(setxkbmap -query | grep -oP 'variant:\s*\K(\w+)')
    echo "$layout" "$variant"
  fi
}

set_kbdlayout() {
  eval "array=($1)"

  if [[ "$usingWayland" == "true" ]]; then
    # Sway: Switch to next keyboard layout
    # Sway cycles through layouts configured in the config, so we just trigger next
    swaymsg input type:keyboard xkb_switch_layout next &&
      spd-say -P important -Cw "${array[@]}"
  else
    # i3: Use setxkbmap
    setxkbmap "${array[@]}" &&
      spd-say -P important -Cw "${array[@]}"
  fi
}

cycle() {
  if [[ "$usingWayland" == "true" ]]; then
    # Sway: Just switch to next layout (Sway handles cycling internally)
    swaymsg input type:keyboard xkb_switch_layout next
    currentLayout=$(get_kbdlayout)
    spd-say -P important -Cw "$currentLayout"
  else
    # i3: Cycle through provided layouts
    currentLayout=$(get_kbdlayout | xargs)
    layouts=("$@" "$1") # add the first one at the end so that it cycles
    index=0
    while [ "${layouts[$index]}" != "$currentLayout" ] && [ $index -lt "${#layouts[@]}" ]; do index=$((index + 1)); done
    nextIndex=$((index + 1))
    nextLayout=${layouts[$nextIndex]}
    set_kbdlayout "$nextLayout"
  fi
}


subcommand="$1"
shift || exit 1

case $subcommand in
  "get")
    echo -n "$(get_kbdlayout)"
    ;;
  "cycle")
    cycle "$@"
    ;;
esac

exit 0