#!/usr/bin/env bash -ex
function header_info {
    cat <<"EOF"
    __ __                     __   ________               
   / //_/__  _________  ___  / /  / ____/ /__  ____ _____ 
  / ,< / _ \/ ___/ __ \/ _ \/ /  / /   / / _ \/ __ `/ __ \
 / /| /  __/ /  / / / /  __/ /  / /___/ /  __/ /_/ / / / /
/_/ |_\___/_/  /_/ /_/\___/_/   \____/_/\___/\__,_/_/ /_/ 
                                                          
EOF
}
set -euo pipefail
shopt -s inherit_errexit nullglob
YW=$(echo "\033[33m")
BL=$(echo "\033[36m")
RD=$(echo "\033[01;31m")
BGN=$(echo "\033[4;92m")
GN=$(echo "\033[1;92m")
DGN=$(echo "\033[32m")
CL=$(echo "\033[m")
BFR="\\r\\033[K"
HOLD="-"
CM="${GN}✓${CL}"
CROSS="${RD}✗${CL}"
PARTY="🎉"
current_kernel=$(uname -r)
clear
header_info
while true; do
    read -p "This will Clean Unused Kernel Images, USE AT YOUR OWN RISK. Proceed(y/n)?" yn
    case $yn in
    [Yy]*) break ;;
    [Nn]*) exit ;;
    *) echo -e "${RD}Please answer y/n${CL}" ;;
    esac
done
clear
function msg_info() {
    local msg="$1"
    echo -ne " ${HOLD} ${YW}${msg}..."
}

function msg_ok() {
    local msg="$1"
    echo -e "${BFR} ${CM} ${GN}${msg}${CL}"
}

function check_root() {
    if [[ $EUID -ne 0 ]]; then
        echo -e "${CROSS}${RD}Error: This script must be ran as the root user.\n${CL}"
        exit 1
    else
        header_info
        edge_kernel
        kernel_info
        kernel_clean
    fi
}

function edge_kernel() {
    if [[ "$current_kernel" == *"edge"* ]]; then
        echo -e "\n${CROSS} ${RD}ERROR:${CL} Proxmox ${BL}${current_kernel}${CL} Kernel Active"
        echo -e "\nAn Active PVE Kernel is required to use Kernel Clean\n"
        exit 1
    fi
}

function kernel_info() {
    if [[ "$MODE" != "PBS" ]]; then
        echo -e "${YW}PVE Version: ${BL}$(pveversion)\n${CL}"
    fi
    if [[ "$current_kernel" == *"pve"* ]]; then
        echo -e "${YW}Current Kernel: ${BL}$current_kernel\n${CL}"
    else
        echo -e "\n${CROSS} ${RD}ERROR: No PVE Kernel Found\n${CL}"
        exit 1
    fi
}

function kernel_clean() {
    kernels=$(dpkg --list | grep 'kernel-.*-pve' | awk '{print $2}' | sort -V)
    remove_kernels=""
    for kernel in $kernels; do
        if [ "$(echo $kernel | grep $current_kernel)" ]; then
            break
        else
            echo -e "${BL}'$kernel' ${CL}${YW}has been added to the remove Kernel list\n${CL}"
            remove_kernels+=" $kernel"
        fi
    done
    msg_ok "Kernel Search Completed\n"
    if [[ "$remove_kernels" != *"pve"* ]]; then
        echo -e "${PARTY}  ${GN}It appears there are no old Kernels on your system. \n${CL}"
        msg_info "Exiting"
        sleep 2
        msg_ok "Done"
    else
        read -p "Would you like to remove the $(echo $remove_kernels | awk '{print NF}') selected Kernels listed above? [y/n]: " -n 1 -r
        echo
        if [[ $REPLY =~ ^[Yy]$ ]]; then
            msg_info "Removing ${CL}${RD}$(echo $remove_kernels | awk '{print NF}') ${CL}${YW}old Kernels${CL}"
            /usr/bin/apt purge -y $remove_kernels >/dev/null 2>&1
            msg_ok "Successfully Removed Kernels"
            msg_info "Updating GRUB"
            /usr/sbin/update-grub >/dev/null 2>&1
            msg_ok "Successfully Updated GRUB"
            msg_info "Exiting"
            sleep 2
            msg_ok "Done"
        else
            msg_info "Exiting"
            sleep 2
            msg_ok "Done"
        fi
    fi
}

if ! command -v pveversion >/dev/null 2>&1; then
    echo -e " Switching to PBS mode"
    MODE="PBS"
    sleep 2
else
    MODE="PVE"
fi

check_root