# Kubernetes course VMs for InfraScience
# 14 Ubuntu 24.04 VMs with m1.large flavor, 100GB root volume, 200GB data volume,
# floating IP and DNS record each.

data "terraform_remote_state" "privnet_dns_router" {
  backend = "local"
  config = {
    path = "../main_net_dns_router/terraform.tfstate"
  }
}

module "labs_common_variables" {
  source = "../../modules/labs_common_variables"
}

module "ssh_settings" {
  source = "../../modules/ssh-key-ref"
}

locals {
  vm_count                = 14
  dns_zone                = data.terraform_remote_state.privnet_dns_router.outputs.dns_zone
  dns_zone_id             = data.terraform_remote_state.privnet_dns_router.outputs.dns_zone_id
  main_private_network_id = data.terraform_remote_state.privnet_dns_router.outputs.main_private_network_id
  main_private_subnet_id  = data.terraform_remote_state.privnet_dns_router.outputs.main_subnet_network_id
  floating_ip_pool        = data.terraform_remote_state.privnet_dns_router.outputs.floating_ip_pools.main_public_ip_pool
  availability_zone       = module.labs_common_variables.availability_zones_names.availability_zone_no_gpu
  default_sg_name         = module.labs_common_variables.default_security_group_name
}

# Look up the default security group by name, scoped to the infrascience project
data "openstack_networking_secgroup_v2" "default" {
  name      = local.default_sg_name
  tenant_id = "3511cd5293dc435ea421aeb0edcfab43"
}

# --- Security group: SSH from anywhere ---
resource "openstack_networking_secgroup_v2" "ssh_from_anywhere" {
  name                 = "corso-k8s-ssh-from-anywhere"
  description          = "Allow SSH access from anywhere"
  delete_default_rules = true
}

resource "openstack_networking_secgroup_rule_v2" "ssh_from_anywhere_ingress" {
  security_group_id = openstack_networking_secgroup_v2.ssh_from_anywhere.id
  direction         = "ingress"
  ethertype         = "IPv4"
  protocol          = "tcp"
  port_range_min    = 22
  port_range_max    = 22
  remote_ip_prefix  = "0.0.0.0/0"
}

# --- Network ports ---
resource "openstack_networking_port_v2" "corso_k8s_port" {
  count          = local.vm_count
  name           = format("corso-k8s-%02d-port", count.index + 1)
  admin_state_up = true
  network_id     = local.main_private_network_id
  security_group_ids = [
    data.openstack_networking_secgroup_v2.default.id,
    openstack_networking_secgroup_v2.ssh_from_anywhere.id,
  ]
  fixed_ip {
    subnet_id = local.main_private_subnet_id
  }
}

# --- Data volumes (200 GB each) ---
resource "openstack_blockstorage_volume_v3" "corso_k8s_data_vol" {
  count                = local.vm_count
  name                 = format("corso-k8s-%02d-data", count.index + 1)
  size                 = 200
  enable_online_resize = true
}

# --- Compute instances ---
resource "openstack_compute_instance_v2" "corso_k8s" {
  count                   = local.vm_count
  name                    = format("corso-k8s-%02d", count.index + 1)
  availability_zone_hints = local.availability_zone
  flavor_name             = "m1.large"
  key_pair                = module.ssh_settings.ssh_key_name

  block_device {
    uuid                  = module.labs_common_variables.ubuntu_2404.uuid
    source_type           = "image"
    volume_size           = 100
    boot_index            = 0
    destination_type      = "volume"
    delete_on_termination = false
  }

  network {
    port = openstack_networking_port_v2.corso_k8s_port[count.index].id
  }

  user_data = file("${module.labs_common_variables.ubuntu2404_data_file}")

  lifecycle {
    ignore_changes = [
      key_pair, user_data, network
    ]
  }
}

# --- Attach data volumes ---
resource "openstack_compute_volume_attach_v2" "corso_k8s_data_vol_attach" {
  count       = local.vm_count
  instance_id = openstack_compute_instance_v2.corso_k8s[count.index].id
  volume_id   = openstack_blockstorage_volume_v3.corso_k8s_data_vol[count.index].id
  device      = "/dev/vdb"
}

# --- Floating IPs ---
resource "openstack_networking_floatingip_v2" "corso_k8s_ip" {
  count       = local.vm_count
  pool        = local.floating_ip_pool
  description = format("Public IP for corso-k8s-%02d", count.index + 1)
}

resource "openstack_networking_floatingip_associate_v2" "corso_k8s_ip" {
  count       = local.vm_count
  floating_ip = openstack_networking_floatingip_v2.corso_k8s_ip[count.index].address
  port_id     = openstack_networking_port_v2.corso_k8s_port[count.index].id
}

# --- DNS records ---
resource "openstack_dns_recordset_v2" "corso_k8s_dns" {
  count       = local.vm_count
  zone_id     = local.dns_zone_id
  name        = format("corso-k8s-%02d.%s", count.index + 1, local.dns_zone.name)
  description = format("Public IP of corso-k8s-%02d", count.index + 1)
  ttl         = 8600
  type        = "A"
  records     = [openstack_networking_floatingip_v2.corso_k8s_ip[count.index].address]
}