resource "kubernetes_service_account" "disk_exporter" {
  metadata {
    name      = "disk-exporter-sa"
    namespace = var.namespace
  }
}

resource "kubernetes_config_map" "disk_exporter" {
  metadata {
    name      = "disk-exporter-config"
    namespace = var.namespace
  }
  data = {
    "exporter.py"      = local.exporter_script
    "requirements.txt" = local.requirements_txt
  }
}

resource "kubernetes_deployment" "disk_exporter" {
  metadata {
    name      = "disk-exporter"
    namespace = var.namespace
    labels = {
      app = "disk-exporter"
    }
  }
  spec {
    replicas = 1
    selector {
      match_labels = {
        app = "disk-exporter"
      }
    }
    strategy {
      type = "RollingUpdate"
    }
    template {
      metadata {
        labels = {
          app = "disk-exporter"
        }
        annotations = {
          "checksum/exporter"     = local.exporter_checksum
          "checksum/requirements" = local.requirements_checksum
        }
      }
      spec {
        service_account_name            = kubernetes_service_account.disk_exporter.metadata[0].name
        automount_service_account_token = false

        container {
          name    = "disk-exporter"
          image   = "python:${var.tag}"
          command = ["sh", "-c", join(" && ", local.commands)]

          env {
            name  = "SMARTCTL_STATIC_VERSION"
            value = var.smartctl_static_version
          }
          env {
            name  = "SMARTCTL_SHA256"
            value = coalesce(var.smartctl_sha256, "")
          }
          env {
            name  = "SMARTCTL_CACHE_BASE"
            value = "/tmp/smartctl-cache"
          }
          env {
            name  = "CHECK_FREQUENCY"
            value = tostring(var.check_frequency)
          }
          env {
            name  = "STANDBY_MODE"
            value = var.standby_mode
          }
          env {
            name  = "EXPORTER_PORT"
            value = "9100"
          }
          env {
            name  = "DEVICE_ROOT"
            value = "/dev"
          }
          port {
            container_port = 9100
            name           = "http-metrics"
          }

          volume_mount {
            name       = "exporter-volume"
            mount_path = "/exporter"
            read_only  = true
          }

          volume_mount {
            name       = "workdir"
            mount_path = "/tmp"
          }

          security_context {
            run_as_user               = 0
            run_as_group              = 0
            read_only_root_filesystem = true
            privileged                = true
          }
        }

        volume {
          name = "exporter-volume"
          config_map {
            name = kubernetes_config_map.disk_exporter.metadata[0].name
          }
        }

        volume {
          name = "workdir"
          host_path {
            path = local.workdir
            type = "DirectoryOrCreate"
          }
        }
      }
    }
  }
}

resource "kubernetes_service" "disk_exporter" {
  metadata {
    name      = "disk-exporter"
    namespace = var.namespace
    labels = {
      app = "disk-exporter"
    }
  }
  spec {
    selector = {
      app = "disk-exporter"
    }
    port {
      port        = 9100
      target_port = 9100
      protocol    = "TCP"
      name        = "http-metrics"
    }
    type = "ClusterIP"
  }
}