Create an alacritty color config from the current X resources

alacritty-colors-from-xresources

#!/usr/bin/env bash
# Generates an alacritty color config from currently loaded X resources.

xrdb_grep() {
    xrdb -query | grep -E '^\*'"$1"':'
}

color_from_line() {
    read -r line && readonly line
    echo "${line/\#/0x}" | tr -d '[:space:]' | cut -d ':' -f 2
}

readonly color_idx=(black red green yellow blue magenta cyan white)

# Begin to print alacritty config.
printf 'colors:\n'

printf '  primary:\n'

printf '    background:\t%s\n' "$(xrdb_grep 'background' | color_from_line)"
printf '    foreground:\t%s\n' "$(xrdb_grep 'foreground' | color_from_line)"

printf '  normal:\n'
declare -i i=0
while read -r line; do
    if [[ $i == 8 ]]; then
        printf '  bright:\n'
    fi

    printf '    %s:\t%s\n' \
        "${color_idx[((i % 8))]}" \
        "$(echo "$line" | color_from_line)"

    i+=1
done < <(xrdb_grep 'color[[:digit:]]+' | sort -V)