terraform {
  backend "local" {}
  required_version = ">= 0.13"
  required_providers {
    kubernetes = {
      source  = "hashicorp/kubernetes"
      version = "2.3.2"
    }
  }
  experiments = [module_variable_optional_attrs]
}


provider "kubernetes" {
  config_path    = "~/.kube/config"
  config_context = "scck8s"
}


variable "namespace" {
  type = string
}

variable "name" {
  type = string
}

variable "ingress_domains" {
  type = list(string)
}

variable "image" {
  type    = string
  default = "dockermirror:5000/dpedu/photolib"
}

variable "replicas" {
  type        = number
  description = "number of web ui server replicas"
  default     = 1
}

variable "requests" {
  type = object({
    cpu    = optional(string)
    memory = optional(string)
  })
  description = "per-pod resource request"
  default     = {}
}

variable "limits" {
  type = object({
    cpu    = optional(string)
    memory = optional(string)
  })
  description = "per-pod resource limit"
  default     = {}
}

variable "database_url" {
  type        = string
  description = "database connection uri"
}

variable "storage_url" {
  type        = string
  description = "uri for storage"
}

variable "cache_url" {
  type        = string
  description = "uri for cache"
}

variable "thumbservice_password" {
  type = string
}


locals {
  requests = defaults(var.requests,
    {
      cpu    = "250m"
      memory = "50Mi"
    }
  )
  limits = defaults(var.limits,
    {
      cpu    = "1"
      memory = "512Mi"
    }
  )
}


resource "kubernetes_deployment" "photolib" {
  metadata {
    name      = var.name
    namespace = var.namespace
    labels = {
      app     = var.name
      service = "${var.name}-web"
    }
  }

  spec {
    replicas = var.replicas

    selector {
      match_labels = {
        app     = var.name
        service = "${var.name}-web"
      }
    }

    template {
      metadata {
        labels = {
          app     = var.name
          service = "${var.name}-web"
        }
      }

      spec {
        enable_service_links = false # TODO some of photolib's env vars conflict with these. In a bad way.

        container {
          name  = "web"
          image = var.image

          env {
            name  = "DATABASE_URL"
            value = var.database_url
          }
          env {
            name  = "STORAGE_URL"
            value = var.storage_url
          }
          env {
            name  = "CACHE_URL"
            value = var.cache_url
          }
          env {
            name  = "THUMB_SERVICE_URL"
            value = "http://_thumbservice:${var.thumbservice_password}@${var.name}-thumbservice.${var.namespace}.svc.cluster.local:8081/thumb"
          }


          resources {
            requests = {
              cpu    = local.requests.cpu
              memory = local.requests.memory
            }
            limits = {
              cpu    = local.limits.cpu
              memory = local.limits.memory
            }
          }

          readiness_probe {
            tcp_socket {
              port = 8080
            }
            initial_delay_seconds = 15
            period_seconds        = 5
            failure_threshold     = 1
            success_threshold     = 2
          }
          liveness_probe {
            tcp_socket {
              port = 8080
            }
            initial_delay_seconds = 15
            period_seconds        = 5
            failure_threshold     = 1
            success_threshold     = 1
          }

          volume_mount {
            mount_path = "/mnt/thumbs"
            name       = "photolib-data"
          }

        }

        volume {
          name = "photolib-data"
          persistent_volume_claim {
            claim_name = kubernetes_persistent_volume_claim.photolib_web_thumbs.metadata.0.name
          }
        }
      }
    }
  }
}

resource "kubernetes_service" "photolib" {
  metadata {
    name      = var.name
    namespace = var.namespace
    labels = {
      app     = var.name
      service = "${var.name}-web"
    }
  }
  spec {
    selector = {
      app     = kubernetes_deployment.photolib.metadata.0.labels.app
      service = kubernetes_deployment.photolib.metadata.0.labels.service
    }
    port {
      protocol    = "TCP"
      port        = 8080
      target_port = 8080
    }
  }
}

resource "kubernetes_ingress" "photolib" {
  metadata {
    name      = var.name
    namespace = var.namespace
    labels = {
      app     = var.name
      service = "${var.name}-web"
    }
  }
  spec {
    dynamic "rule" {
      for_each = var.ingress_domains
      content {
        host = rule.value
        http {
          path {
            backend {
              service_name = kubernetes_service.photolib.metadata.0.name
              service_port = 8080
            }
          }
        }
      }
    }
  }
}

resource "kubernetes_persistent_volume" "photolib_web_thumbs" {
  metadata {
    name = "${var.name}-web-thumbs"
    labels = {
      app     = var.name
      service = "${var.name}-web"
    }
  }
  spec {
    storage_class_name = "manual"
    capacity = {
      storage = "8Gi"
    }
    access_modes = ["ReadWriteMany"]
    persistent_volume_source {
      host_path {
        path = "/mnt/k8store1/vols/photolib/thumbs" # LOL
      }
    }
  }
}

resource "kubernetes_persistent_volume_claim" "photolib_web_thumbs" {
  metadata {
    name      = kubernetes_persistent_volume.photolib_web_thumbs.metadata.0.name
    namespace = var.namespace
  }
  spec {
    storage_class_name = "manual"
    access_modes       = ["ReadWriteMany"]
    resources {
      requests = {
        storage = "8Gi"
      }
    }
  }
}


# TODO switch to openebs volume for thumbs



resource "kubernetes_deployment" "thumbservice" {
  metadata {
    name      = "${var.name}-thumbservice"
    namespace = var.namespace
    labels = {
      app     = var.name
      service = "${var.name}-thumbservice"
    }
  }

  spec {
    replicas = 1

    selector {
      match_labels = {
        app     = var.name
        service = "${var.name}-thumbservice"
      }
    }

    template {
      metadata {
        labels = {
          app     = var.name
          service = "${var.name}-thumbservice"
        }
      }

      spec {
        enable_service_links = false # TODO some of photolib's env vars conflict with these. In a bad way.

        container {
          name  = "thumbservice"
          image = var.image

          command = [
            "photothumbd"
          ]


          env {
            name  = "DATABASE_URL"
            value = var.database_url
          }
          env {
            name  = "STORAGE_URL"
            value = var.storage_url
          }
          env {
            name  = "CACHE_URL"
            value = var.cache_url
          }

          resources {
            requests = {
              cpu    = local.requests.cpu
              memory = local.requests.memory
            }
            limits = {
              cpu    = local.limits.cpu
              memory = local.limits.memory
            }
          }

          readiness_probe {
            tcp_socket {
              port = 8081
            }
            initial_delay_seconds = 15
            period_seconds        = 5
            failure_threshold     = 1
            success_threshold     = 2
          }
          liveness_probe {
            tcp_socket {
              port = 8081
            }
            initial_delay_seconds = 15
            period_seconds        = 5
            failure_threshold     = 1
            success_threshold     = 1
          }

          volume_mount {
            mount_path = "/mnt/thumbs"
            name       = "photolib-data"
          }

        }

        volume {
          name = "photolib-data"
          persistent_volume_claim {
            claim_name = kubernetes_persistent_volume_claim.photolib_web_thumbs.metadata.0.name
          }
        }
      }
    }
  }
}

resource "kubernetes_service" "thumbservice" {
  metadata {
    name      = "${var.name}-thumbservice"
    namespace = var.namespace
    labels = {
      app     = var.name
      service = "${var.name}-thumbservice"
    }
    # annotations = {
    #   "kube-router.io/service.hairpin" = ""
    # }
  }
  spec {
    selector = {
      app     = kubernetes_deployment.thumbservice.metadata.0.labels.app
      service = kubernetes_deployment.thumbservice.metadata.0.labels.service
    }
    port {
      protocol    = "TCP"
      port        = 8081
      target_port = 8081
    }
  }
}