#!/bin/bash

[[ -z "$VM_UUID" ]] || {
  echo "Environment variable VM_UUID is not set."
  exit 1
}
source "/etc/detee/daemon/vms/$VM_UUID"

mandatory_vars=("IF_DEVICE" "IF_NAME" "IF_TYPE" "KERNEL" \
  "INITRD" "PARAMS" "CPU_TYPE" "VCPUS" "MEMORY" \
  "MAX_MEMORY" "DISK" "DISK_SIZE")
for var in "${mandatory_vars[@]}"; do
  if [ -z "${!var}" ]; then
    echo "Environment variable $var is not set."
    exit 1
  fi
done

if [[ "$IF_TYPE" == "macvtap" || "$IF_TYPE" == "ipvtap" ]]; then
  ip link add link $IF_DEVICE name $IF_NAME type $IF_TYPE mode bridge
  ip link set $IF_NAME up
  ip link set $IF_NAME promisc on
  vtap_index="$(cat /sys/class/net/${IF_NAME}/ifindex)"
  vtap_addr="$(cat /sys/class/net/${IF_NAME}/address)"
  qemu_device_params="-netdev tap,id=hostnet1,fd=3 3<>/dev/tap${macvtap_index}"
  qemu_device_params+=" -device virtio-net-pci,netdev=hostnet1,mac=${macvtap_addr},romfile="
fi

if [[ "$IF_TYPE" == "NAT" ]]; then 
  ports=""
  for port_pair in "$NAT_PORT_FW"; do
    host_port="$( echo $port_pair | cut -d ':' -f1 )"
    guest_port="$( echo $port_pair | cut -d ':' -f2 )"
    ports+=",hostfwd=tcp::${host_port}-:${guest_port}"
  done
  qemu_device_params="-netdev user,id=vmnic${ports}"
  qemu_device_params+=" -device virtio-net-pci,netdev=vmnic,romfile="
fi

# TODO: also handle bridge device (when IPs are public, but the host is the gateway)

vm_disk="/root/dtrfs/arch-1-ghe0.qcow2"

[[ -f $DISK ]] || qemu-img create -f qcow2 ${DISK} ${DISK_SIZE}

qemu-system-x86_64 $qemu_device_params \
    -enable-kvm -cpu $CPU_TYPE -vga none \
    -machine q35,confidential-guest-support=sev0,memory-backend=ram1 \
    -smp $VCPUS,maxcpus=255 -m $MEMORY,slots=5,maxmem=$MAX_MEMORY \
    -no-reboot -bios /usr/share/edk2/ovmf/OVMF.amdsev.fd \
    -drive file=${DISK},if=none,id=disk0,format=qcow2 \
    -device virtio-blk-pci,drive=disk0 \
    -object memory-backend-memfd,id=ram1,size=$MEMORY,share=true,prealloc=false \
    -object sev-snp-guest,id=sev0,cbitpos=51,reduced-phys-bits=1,kernel-hashes=on \
    -kernel $KERNEL -append "$PARAMS" -initrd $INITRD \
    -nographic -monitor pty -serial mon:stdio -monitor unix:monitor,server,nowait