qemuDir=$(cd "${BASH_SOURCE[0]%/*}" && pwd)

tmpDir=/tmp/nix-bitcoin-qemu-vm
mkdir -p $tmpDir

# Cleanup on exit
cleanup() {
    set +eu
    if [[ $qemuPID ]]; then
        kill -9 $qemuPID
    fi
    rm -rf $tmpDir
}
trap "cleanup" EXIT

identityFile=$qemuDir/id-vm
chmod 0600 $identityFile

runVM() {
    vm=$1
    vmNumCPUs=$2
    vmMemoryMiB=$3
    sshPort=$4

    export NIX_DISK_IMAGE=$tmpDir/img
    export QEMU_NET_OPTS=hostfwd=tcp::$sshPort-:22
    </dev/null $vm/bin/run-*-vm -m $vmMemoryMiB -smp $vmNumCPUs &>/dev/null &
    qemuPID=$!
}

vmWaitForSSH() {
    echo
    printf "Waiting for SSH connection..."
    while ! c : 2>/dev/null; do :; done
    echo
}

# Run command in VM
c() {
    ssh -p $sshPort -i $identityFile -o ConnectTimeout=1 \
        -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null -o LogLevel=ERROR \
        -o ControlMaster=auto -o ControlPath=$tmpDir/ssh-connection -o ControlPersist=60 \
        root@127.0.0.1 "$@"
}
export identityFile
export sshPort
export tmpDir
export -f c