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

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

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

STATE_DIR="${HOME}/.local/state/sisyphus"
STATE_FILE="${STATE_DIR}/theme"
BG_DIR="${HOME}/Nextcloud/Afbeeldingen/wallpapers"

LATITUDE='50.50N' # Belgium
LONGITUDE='4.00E'

# Mapping inputs to themes

declare -A theme_name
theme_name['light']="${THEME_LIGHT}"
theme_name['dark']="${THEME_DARK}"

declare -A theme_time
theme_time['DAY']="${THEME_LIGHT}"
theme_time['NIGHT']="${THEME_DARK}"

# Mapping of current theme to next theme

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

# Mapping of theme to applications

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

declare -A gtk_theme
gtk_theme[${THEME_LIGHT}]='Adwaita'
gtk_theme[${THEME_DARK}]='Adwaita-dark'

declare -A wallpaper
wallpaper[${THEME_LIGHT}]="bg-light"
wallpaper[${THEME_DARK}]="bg-dark"

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

# Parse options
while getopts ":m:gt" option; do
    case "${option}" in
        m)
            if [ -z "${theme_name[${OPTARG}]}" ]; then
                >&2 printf "Error: Invalid mode: '%s'.\nShould be either 'light' or 'dark'\n" "${option}"
                exit 1
            fi
            theme="${theme_name[${OPTARG}]}"
            ;;
        g)
            current_state="$(cat "${STATE_FILE}")"
            next_state="${theme_next[${current_state}]}"
            if [ "${current_state}" == "${THEME_DARK}" ]; then
                class='activated'
                percentage=100
            fi
            printf '{"alt": "%s", "tooltip": "Set theme to %s", "percentage": %d, "class": "%s"}' \
                "${gsettings_alt[${current_state}]}" "${next_state}" "${percentage:=0}" "${class:="none"}"
            exit 0
            ;;
        t)
            if ! [ "$(command -v sunwait)" ]; then
                >&2 printf "Error: sunwait command not found. Please install sunwait or do not use the -t option.\n"
                exit 1
            fi

            current_time="$(sunwait poll "${LATITUDE}" "${LONGITUDE}")"

            if [ -z "${current_time}" ] || [ -z "${theme_time[${current_time}]}" ]; then
                >&2 printf "Error: Invalid time returned by sunwait: '%s'.\nInspect the script for more details.\n" "${current_time}"
                exit 1
            fi

            theme="${theme_time[${current_time}]}"
            printf "Setting theme based on time of day: %s -> %s\n" "${current_time}" "${theme}"
            ;;
        *)
            >&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

# Determine the theme to set
if [ -z "${theme}" ]; then
    # Read from state file
    if [ -f "${STATE_FILE}" ]; then
        previous_theme="$(cat "${STATE_FILE}")"
    fi

    if [ -n "${previous_theme}" ]; then
        theme="${theme_next[${previous_theme}]}"
    else
        theme="${THEME_DEFAULT}"
    fi
fi

# Store the new theme in the state file
echo "${theme}" > "${STATE_FILE}"

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

# Update terminal colors by sending it OSC sequences.
# Alternatively, you could use theme.sh (https://github.com/lemnos/theme.sh)
# Function below loosely based on theme.sh and https://codeberg.org/dnkl/foot/issues/708
function update_terminal_colors() {
    for pid in $(pgrep zsh); do
        if [ "${theme}" == "${THEME_LIGHT}" ]; then
            printf "\033]10;#000000\007" >> /proc/${pid}/fd/0
            printf "\033]11;#ffffff\007" >> /proc/${pid}/fd/0
        elif [ "${theme}" == "${THEME_DARK}" ]; then
            printf "\033]10;#ffffff\007" >> /proc/${pid}/fd/0
            printf "\033]11;#000000\007" >> /proc/${pid}/fd/0
        fi
    done
}

# Foot
if [ "$(command -v foot)" ] ; then
    # Make color theme switch 'permanent'.
    echo "include=~/.config/foot/themes/${theme}.ini" > ~/.config/foot/theme.ini &
    # We will have to change the terminal colors ourselves.
    update_terminal_colors &
fi

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

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

# Sway
if [ "$(command -v swaybg)" ]; then
    bg_path="${BG_DIR}/${wallpaper[${theme}]}"
    /run/current-system/sw/bin/cp "${bg_path}" "${STATE_DIR}/bg"
    if [ "$(command -v swaymsg)" ]; then
        pkill swaybg && swaymsg exec "swaybg -m fill -i ${STATE_DIR}/bg" &
    elif [ "$(command -v hyprctl)" ]; then
        pkill swaybg && hyprctl keyword exec "swaybg -m fill -i ${STATE_DIR}/bg" &
    fi
fi

# Vifm
if [ "$(command -v vifm)" ]; then
    echo "colorscheme ${theme} Default-256 Default" > ~/.config/vifm/theme.conf
    # Update all running instances
    vifm --remote -c "colorscheme ${theme}" &
fi

# Vim
if [ "$(command -v vim)" ]; then
    echo "colorscheme ${theme}" > ~/.vim/theme.conf
    # Update all running instances
    for server in $(vim --serverlist); do
        vim --servername "${server}" --remote-send "<C-\><C-N>:colorscheme ${theme}<CR>"
    done
fi