#!/usr/bin/env bash
# set -vx

# Copyright (C) 2022 Brian Hayes

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published
# by the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program 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 Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

printhelp() {
    cat <<EOM
usage: dye [-h|-r] [color_code]
options:
 -x             hex code to rgb
 -r                  rgb to hex
examples:
 dye -x "#FFFFFF"
 dye -r 255 255 255
EOM
    exit 1
}

hex_to_rgb() {
    : "${1/\#/}"
    ((r = 16#${_:0:2}, g = 16#${_:2:2}, b = 16#${_:4:2}))
    printf '%s\n' "rgb($r, $g, $b)"
}

rgb_to_hex() {
    printf '#%02x%02x%02x\n' "$1" "$2" "$3"
}

error() {
    printf "error: %s\n" "$1" 1>&2
    ${2:+exit $2}
}

dependencycheck() {
    local dep missingdependencies=0
    for dep in "$@"; do
        if ! command -v "$dep" &>/dev/null; then
            error "dependency not met: $dep"
        fi
    done
    if [[ $missingdependencies -gt 0 ]]; then
        exit 1
    fi
}

main() {
    if [[ "$#" -lt 1 ]]; then
        printhelp
    fi

    while getopts ":x:r:?" arg; do
        case $arg in
            x)
                rgbval=$(hex_to_rgb "${2:-''}")
                printf "%s\n" "$rgbval"
                read -e -r -p "save code to clipboard?(y/n): " clipit
                if [[ "$clipit" == "yes" || "$clipit" == "y" ]]; then
                    dependencycheck xclip
                    printf "%s" "$rgbval" | xclip -sel clip
                fi
                ;;
            r)
                hexval=$(rgb_to_hex "${2:-''}")
                printf "%s\n" "$hexval"
                read -e -r -p "save code to clipboard?(y/n): " clipit
                if [[ "$clipit" == "yes" || "$clipit" == "y" ]]; then
                    dependencycheck xclip
                    printf "%s" "$hexval" | xclip -sel clip
                fi
                ;;
            ?)
                printhelp
                ;;
        esac
    done
}

main "$@"

# Credits:
# hex_to_rgb() and rgb_to_hex() taken from Akash Mittal:
# https://akashmittal.com/code-example-convert-hex-color-to-rgb-rgb-to-hex-using-bash-script/
# https://www.linkedin.com/in/akashrishimittal/
#
# error() and dependencycheck() copied from tomocafe:
# https://github.com/tomocafe