// Compute
// ----------------------------------

// The instance for K3S
resource "google_compute_instance" "k3s" {
  name         = "k3s-vm-1"
  machine_type = "e2-small" # This instance will have 2 Gb of RAM
  zone         = var.zone

  tags = ["web"]

  // Set the boot disk and the image (10 Gb)
  boot_disk {
    initialize_params {
      image = "debian-cloud/debian-12"
      size  = 10
    }
  }

  // Configuration to be a Spot Instance, to reduce costs
  scheduling {
    automatic_restart = true
  }
  # scheduling {
  #   preemptible                 = false
  #   automatic_restart           = true
  #   provisioning_model          = "SPOT"
  #   instance_termination_action = "STOP"
  # }

  // attach a disk for K3S
  attached_disk {
    source      = google_compute_disk.k3s_disk.id
    device_name = "k3s-disk"
  }

  // attach a disk for app data
  attached_disk {
    source      = google_compute_disk.app_data_disk.id
    device_name = "app-data-disk"
  }

  network_interface {
    network = "default"

    // enable ephemeral ip
    access_config {}
  }

  labels = {
    env       = var.env
    region    = var.region
    app       = var.app_name
    sensitive = "false"
  }

  metadata_startup_script   = file("scripts/k3s-vm-startup.sh")
  allow_stopping_for_update = true
}


// Storage
// ----------------------------------

// The disk attached to the instance (15 Gb)
resource "google_compute_disk" "k3s_disk" {
  name = "k3s-disk"
  size = 15
  type = "pd-standard"
  zone = var.zone
}

// The disk for app data (20 Gb)
resource "google_compute_disk" "app_data_disk" {
  name = "app-data-disk"
  size = 20
  type = "pd-standard"
  zone = var.zone
}


// load balancer ....


# resource "google_compute_health_check" "http_health_check" {
#   name                = "http-health-check"
#   check_interval_sec  = 5
#   timeout_sec         = 5
#   healthy_threshold   = 2
#   unhealthy_threshold = 2

#   http_health_check {
#     port = 80
#   }
# }

resource "google_compute_http_health_check" "http_health_check" {
  name                = "http-health-check"
  request_path        = "/"
  port                = 80
  check_interval_sec  = 5
  timeout_sec         = 5
  healthy_threshold   = 2
  unhealthy_threshold = 2
}


# resource "google_compute_target_pool" "k3s_pool" {
#   name          = "k3s-target-pool"
#   instances     = [google_compute_instance.k3s.self_link]
#   health_checks = [google_compute_health_check.http_health_check.self_link]
# }

resource "google_compute_target_pool" "k3s_pool" {
  name          = "k3s-target-pool"
  instances     = [google_compute_instance.k3s.self_link]
  health_checks = [google_compute_http_health_check.http_health_check.self_link]
}

resource "google_compute_forwarding_rule" "http_forwarding_rule" {
  name                  = "http-forwarding-rule"
  target                = google_compute_target_pool.k3s_pool.self_link
  port_range            = "80"
  ip_protocol           = "TCP"
  load_balancing_scheme = "EXTERNAL"
}

resource "google_compute_forwarding_rule" "https_forwarding_rule" {
  name                  = "https-forwarding-rule"
  target                = google_compute_target_pool.k3s_pool.self_link
  port_range            = "443"
  ip_protocol           = "TCP"
  load_balancing_scheme = "EXTERNAL"
}



// ----------------------------------



data "google_project" "project" {
  project_id = var.project_name # Use variable from tfvars
}

output "project_number" {
  value = data.google_project.project.number
}

output "k3s_vm_public_ip" {
  value       = google_compute_instance.k3s.network_interface[0].access_config[0].nat_ip
  description = "Ephemeral public IP of the k3s VM"
}

output "load_balancer_ip" {
  value       = google_compute_forwarding_rule.http_forwarding_rule.ip_address
  description = "External IP address of the load balancer (HTTP)"
}