resource "google_compute_subnetwork" "gke" {
  name          = "${var.region}-gke-subnet"
  ip_cidr_range = var.subnet_cidr_range
  region        = var.region
  network       = data.terraform_remote_state.global.outputs.google_compute_network
  project       = var.project
  secondary_ip_range {
    range_name    = "${var.region}-internal-pods"
    ip_cidr_range = var.pods_cidr_range
  }
  secondary_ip_range {
    range_name    = "${var.region}-internal-services"
    ip_cidr_range = var.services_cidr_range
  }
}

resource "google_compute_router" "gke-router" {
  name    = "gke-router"
  region  = google_compute_subnetwork.gke.region
  network = data.terraform_remote_state.global.outputs.google_compute_network
}

resource "google_compute_address" "gke-nat-ip" {
  count  = 1
  name   = "nat-manual-ip-${count.index}"
  region = var.region
}

resource "google_compute_router_nat" "gke-nat-manual" {
  name   = "gke-router-nat"
  router = google_compute_router.gke-router.name
  region = var.region

  nat_ip_allocate_option = "MANUAL_ONLY"
  nat_ips                = google_compute_address.gke-nat-ip.*.self_link

  source_subnetwork_ip_ranges_to_nat = "LIST_OF_SUBNETWORKS"

  subnetwork {
    name                    = google_compute_subnetwork.gke.id
    source_ip_ranges_to_nat = ["ALL_IP_RANGES"]
  }
}