#!/usr/bin/env bash
# Toggle light- or dark-mode for your applications
# Usage: toggle [-m light|dark]

#################
### Variables ###
#################

THEME_LIGHT='tdpeuter-light'
THEME_DARK='tdpeuter-dark'
THEME_DEFAULT="${THEME_LIGHT}"

STATE_FILE="${HOME}/.local/state/sisyphus/theme"

declare -A theme_next
theme_next[${THEME_LIGHT}]="${THEME_DARK}"
theme_next[${THEME_DARK}]="${THEME_LIGHT}"

declare -A gsettings_alt
gsettings_alt[${THEME_LIGHT}]='default'
gsettings_alt[${THEME_DARK}]='prefer-dark'

#############
### Logic ###
#############

# Parse options
while getopts ":m:" option; do
    case "${option}" in
        m)
            if [ "${OPTARG}" == 'light' ]; then
                theme="${THEME_LIGHT}"
            elif [ "${OPTARG}" == 'dark' ]; then
                theme="${THEME_DARK}"
            else
                >&2 printf "Error: Invalid mode: '%s'.\nShould be either 'light' or 'dark'\n" "${option}"
                exit 1
            fi
            ;;
        *)
            >&2 printf "Error: Invalid option: '%s'.\n" "${option}"
            exit 1
            ;;
    esac
done
shift $(( OPTIND - 1 ))

# Check if the state file exists
if ! [ -d "$(dirname ${STATE_FILE})" ]; then
    mkdir -p "$(dirname ${STATE_FILE})"
fi

# Choose next theme
previous_theme="$(cat ${STATE_FILE})"
if ! [[ -z "${previous_theme}" || "${theme}" ]]; then
    theme="${theme_next[${previous_theme}]}"
fi
echo "${theme:=${THEME_DEFAULT}}" > "${STATE_FILE}"

######################
### Set all themes ###
######################

# GNOME
if [ "$(command -v gsettings)" ]; then
    gsettings set org.gnome.desktop.interface color-scheme "${gsettings_alt[${theme}]}"
fi

# Kitty
if [ "$(command -v kitty)" ]; then
    kitten themes --config-file-name theme.conf "${theme}"
fi

# Vim
# This does not reload the config, but will use it when you restart vim
# Toggle an existing window using `:colorscheme ${theme}`
if [ "$(command -v vim)" ]; then
    echo "colorscheme ${theme}" > ~/.vim/theme.conf
fi