Vagrant.configure("2") do |config|

    controller_hostname = "controller"
    controller_ip = "192.168.56.101"

    config.vm.provider "virtualbox" do |virtualbox|
        virtualbox.customize ["modifyvm", :id, "--graphicscontroller", "vmsvga"]
        virtualbox.memory = 1024
        virtualbox.cpus = 1
    end

    config.vm.box = "ubuntu/focal64"

    config.vm.provision "shell", inline: <<-SHELL
        apt update
        apt -y install mpich
    SHELL

    config.vm.define "controller", primary: true do |controller|
        controller.vm.hostname = "#{controller_hostname}"

        controller.vm.provision "file", source: "id_ed25519", destination: "~/.ssh/id_ed25519"
        controller.vm.provision "file", source: "ssh_config.txt", destination: "~/.ssh/config"
        controller.vm.provision "file", source: "mpi_hosts.txt", destination: "~/mpi_hosts"
        controller.vm.provision "shell", inline: "chmod go-rwx /home/vagrant/.ssh/id*"

        controller.vm.network "private_network", ip: "#{controller_ip}", name: "VirtualBox Host-Only Ethernet Adapter"
    end

    (1..3).each do |i|
        config.vm.define "worker-#{i}" do |worker|
            worker.vm.network "private_network", ip: "192.168.56.#{200+i}", name: "VirtualBox Host-Only Ethernet Adapter"
            worker.vm.hostname = "worker-#{i}"
            worker.vm.provision "file", source: "id_ed25519.pub", destination: "~/.ssh/id_ed25519.pub"
            worker.vm.provision "shell", inline: <<-SHELL
                echo #{controller_ip} #{controller_hostname} >> /etc/hosts
                cat /home/vagrant/.ssh/id_ed25519.pub >> /home/vagrant/.ssh/authorized_keys
            SHELL
        end
    end

end