#!/bin/bash -e
DIR="$(dirname "${BASH_SOURCE[0]}")"

BRIDGE=virbr0

NORMAL=$'\e[0m'
BOLD=$'\e[1m'
RED=$'\e[31m'

ask_yn() {
    local a

    read -rp "$* (Y/n) " a
    [ -z "$a" ] || [[ "${a,,}" == y* ]]
}

declare -A ISO
declare -a OPTS
download_isos() {
    local curl file

    curl=(curl -ZLC-)
    for iso in "${!ISO[@]}"; do
        file="$iso.iso"
        curl+=(-o "$file" "${ISO[$iso]}")
        OPTS+=(-drive "file=$file,media=cdrom,readonly=on")
    done
    "${curl[@]}"
}

_getmaxram() {
    local ram; ram="$(free -g | awk '/^Mem:/{print $2 - 2}')"

    if   [ "$ram" -le  2 ]; then  ram=2
    elif [ "$ram" -gt 32 ]; then ram=32; fi
    echo "${ram}G"
}

_getnet() {
    local net=user

    if ! ip link show "$BRIDGE" | grep -q UP; then
        ask_yn 'create bridge?' && sudo "$DIR/startnat.sh" "$BRIDGE" > /dev/null
    fi
    if ip link show "$BRIDGE" | grep -q UP; then
        net="bridge,br=$BRIDGE"
    fi
    echo "$net"
}

qemu() {
    local ram=2G
    local maxram; maxram="$(_getmaxram)"
    local net; net="$(_getnet)"

    (set -x
        qemu-system-x86_64 -accel kvm \
            -monitor stdio \
            -M q35 \
            -bios /usr/share/edk2/x64/OVMF.4m.fd \
            -cpu host \
            -m "$ram,maxmem=$maxram" \
            -vga virtio \
            -audio pipewire,model=hda \
            -drive if=virtio,file=hda.qcow2 \
            -nic "model=virtio-net-pci,type=$net" \
            -device qemu-xhci \
            -object "memory-backend-ram,id=mem,size=$ram,share=on" \
            -numa node,memdev=mem \
            "${OPTS[@]}" \
            "$@"
    )
}