#  Licensed under the Apache License, Version 2.0 (the "License"); you may
#  not use this file except in compliance with the License. You may obtain
#  a copy of the License at
#
#       http://www.apache.org/licenses/LICENSE-2.0
#
#  Unless required by applicable law or agreed to in writing, software
#  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#  License for the specific language governing permissions and limitations
#  under the License.

Namespaces:
  =: com.mirantis.docker.kubernetes
  docker: com.mirantis.docker
  std: io.murano
  sys: io.murano.system

Name: KubernetesPod

Extends:
  - docker:DockerContainerHost
  - docker:DockerHelpers

Properties:
  name:
    Contract: $.string().notNull()

  kubernetesCluster:
    Contract: $.class(KubernetesCluster).notNull()

  labels:
    Contract: $.string().notNull()  # convert to key-value map as soon as it will be possible to input it in UI
    Default: ''

  replicas:
    Contract: $.int().notNull().check($ >= 0)
    Usage: InOut


Methods:
  .init:
    Body:
      - $._environment: $.find(std:Environment).require()
      - $._podDefinition: null


  # this is a workaround for early initialization. If docker application was deleted
  # its destroy method will call deleteContainer method that will change _podDefinition
  # on KubernetesPod loaded from ObjectsCopy
  # but ininitialize method on a KubernetesPod from Objects is called before destruction
  # and because we have 2 different KubernetesPod objects that share attributes but
  # not private variables _podDefinition of real object will still contain outdated data
  _loadCurrentPodDefinition:
    Body:
      - If: $._podDefinition = null
        Then:
          - $podName: $._getPodName()
          - $podDefinition: $.getAttr(lastPodDeployed, null)
          - If: $podDefinition = null
            Then:
              - $podDefinition:
                  apiVersion: v1
                  kind: Pod
                  metadata:
                    name: $podName
                    labels: $._getPodLabels($podName)
                  spec:
                    containers: []
                    volumes: []

              - $.setAttr(lastPodDeployed, $podDefinition)
          - $._podDefinition: $podDefinition
      - Return: $._podDefinition


  _getPodName:
    Body:
      - Return: $.name.toLower()

  _getPodLabels:
    Arguments:
      - podName:
          Contract: $.string().notNull()
    Body:
      Return: $.labels2Map($.labels.toLower()).mergeWith(dict(id => $podName))

  hostContainer:
    Arguments:
      - container:
          Contract: $.class(docker:DockerContainer)
    Body:
      - $._loadCurrentPodDefinition()
      - $podName: $._getPodName()
      - For: port
        In: $container.ports
        Do:
        - $endpoints: $.kubernetesCluster.serviceEndpoints.where(
            $.containerPort = $port.port and $.protocol = $port.protocol and $.podId = $podName)
        - If: len($endpoints) > 0
          Then:
            - $msg: format('Port {0} is already used in the Pod {1}', $port.port, $.name)
            - Throw: PortConflictException
              Message: $msg
      - $._deleteContainer($container.name)

      - $containerDef:
          name: $container.name.toLower()
          image: $container.image
          args: $container.commands
          ports: $container.ports.select($this._getPortDefinition($))
          volumeMounts: $container.volumes.keys().select(
            dict(
              name => $this._generateVolumeName($container.name, $container.volumes.get($)),
              mountPath => $
            ))
          env: $container.env.keys().select(dict(name => $, value => $container.env.get($)))

      - $newVolumes: $container.volumes.values().select(
          $this._buildVolumeEntry($container.name, $))

      - $diff:
          spec:
            containers: [$containerDef]
            volumes: $newVolumes
      - $._podDefinition: $._podDefinition.mergeWith($diff)
      - $.deploy()
      - $._environment.reporter.report($, 'Creating services for Pod {0}'.format($.name))
      - $.kubernetesCluster.createService(
            applicationName => $container.name,
            applicationPorts => $container.ports,
            podId => $podName)
      - Return: $.getEndpoints($container.name)


  getEndpoints:
    Arguments:
      - applicationName:
          Contract: $.string().notNull()
    Body:
      - Return: $.kubernetesCluster.serviceEndpoints.where($.applicationName = $applicationName)


  _getPortDefinition:
    Arguments:
      - port:
          Contract: $.class(docker:ApplicationPort).notNull()
    Body:
      - $result:
          containerPort: $port.port
      - If: $port.scope = node
        Then:
          $result.hostPort: $port.port
      - Return: $result


  _buildVolumeEntry:
    Arguments:
      - name:
          Contract: $.string().notNull()
      - volume:
          Contract: $.class(docker:DockerVolume).notNull()
    Body:
      - $type: $volume.getType()
      - Value: $type
        Match:
          HostDir:
            - $spec:
                hostDir:
                  path: $volume.getParameters()
          TempVolume:
            - $spec:
                emptyDir: {}
        Default:
          - Throw: UnknownDockerVolumeType
            Message: format('Unknown docker volume type {0}', $type)
      - Return:
          name: $._generateVolumeName($name, $volume)
          source: $spec


  _deleteContainer:
    Arguments:
      - name:
          Contract: $.string().notNull()
    Body:
      - $lenBefore: len($._podDefinition.spec.containers) + len($._podDefinition.spec.volumes)
      - $containerName: $name.toLower()
      - $newContainers: $._podDefinition.spec.containers.where($.name != $containerName)
      - $volumeNameMap: $.getAttr(volumeNameMap, dict())
      - $newVolumeNameMap: {}
      - $volumesToDelete: []
      - $prefix: format('{0}/'.format($name))
      - For: key
        In: $volumeNameMap.keys()
        Do:
          - $volumeName: $volumeNameMap.get($key)
          - If: $key.startsWith($prefix)
            Then:
              - $volumesToDelete: $volumesToDelete + list($volumeName)
            Else:
              - $newVolumeNameMap[$key]: $volumeName
      - $.setAttr(volumeNameMap, $newVolumeNameMap)

      - $newVolumes: $._podDefinition.spec.volumes.where(
            not ($.name in $volumesToDelete))
      - If: len($newContainers) + len($newVolumes) != $lenBefore
        Then:
          - $._podDefinition.spec.containers: $newContainers
          - $._podDefinition.spec.volumes: $newVolumes


  deleteContainer:
    Arguments:
      - name:
          Contract: $.string().notNull()
    Body:
      - If: $.kubernetesCluster.isAvailable()
        Then:
          - $._loadCurrentPodDefinition()
          - $._deleteContainer($name)
          - $.kubernetesCluster.deleteServices(
                applicationName => $name,
                podId => $._getPodName())
          - $.deploy()


  _generateVolumeName:
    Arguments:
      - name:
          Contract: $.string().notNull()
      - volume:
          Contract: $.class(docker:DockerVolume).notNull()
    Body:
      - $key: format('{0}/{1}', $name, $volume.name)
      - $map: $.getAttr(volumeNameMap, dict())
      - $volumeName: $map.get($key)
      - If: $volumeName = null
        Then:
          - $volumeName: randomName()
          - $map[$key]: $volumeName
          - $.setAttr(volumeNameMap, $map)
      - Return: $volumeName


  deploy:
    Body:
      - $._loadCurrentPodDefinition()
      - $prevPod: $.getAttr(lastPodDeployed, null)
      - $prevReplicas: $.getAttr(lastReplicas, 0)

      - $podDefinition: $._podDefinition
      - $replicas: $.replicas
      - If: len($podDefinition.spec.containers) = 0
        Then:
          - $replicas: 0
      - $.setAttr(lastReplicas, $replicas)
      - If: $replicas != $prevReplicas or $prevPod != $podDefinition
        Then:
          - If: $replicas > 0
            Then:
              - $._environment.reporter.report($, 'Deploying Replication Controller for Pod {0}'.format($.name))
              - $rcDefinition: $._buildReplicationControllerDefinition($podDefinition)
              - $.kubernetesCluster.createReplicationController(
                    definition => $rcDefinition, isNew => $prevReplicas = 0)
          - If: $replicas = 0 and $prevReplicas > 0
            Then:
              - $.kubernetesCluster.deleteReplicationController($._getReplicationControllerId())
          - If: $prevPod != $podDefinition and len($prevPod.spec.containers) > 0
            Then:
              - $.kubernetesCluster.deletePods(dict(id => $._getPodName()))
          - If: $.replicas = 0 and len($podDefinition.spec.containers) > 0
            Then:
              - $.kubernetesCluster.createPod(definition => $podDefinition, isNew => true)

          - $._environment.reporter.report($, 'Pod {0} is ready'.format($.name))
          - $.setAttr(lastPodDeployed, $podDefinition)


  _buildReplicationControllerDefinition:
    Arguments:
      - podDefinition:
          Contract: {}
    Body:
      Return:
        apiVersion: v1
        kind: ReplicationController
        metadata:
          name: $._getReplicationControllerId()
          labels: $podDefinition.metadata.labels
        spec:
          replicas: $.replicas
          selector:
            id: $._getPodName()
          template:
            metadata:
              labels: $podDefinition.metadata.labels
            spec: $podDefinition.spec


  _getReplicationControllerId:
    Body:
      - Return: $._getPodName()


  getInternalScopeId:
    Body:
      Return: id($.kubernetesCluster)

  scalePodDown:
    Usage: Action
    Body:
      - If: $.replicas > 1
        Then:
          - $._environment.reporter.report($this, 'Scaling Pod down')
          - $.replicas: $.replicas - 1
          - $.kubernetesCluster.scaleRc(rcName => $._getReplicationControllerId(), newSize => $.replicas)
        Else:
          - $._environment.reporter.report($this, 'Cannot scale Pod down')


  scalePodUp:
    Usage: Action
    Body:
      - If: $.replicas > 0
        Then:
          - $._environment.reporter.report($this, 'Scaling Pod up')
          - $.replicas: $.replicas + 1
          - $.kubernetesCluster.scaleRc(rcName => $._getReplicationControllerId(), newSize => $.replicas)
        Else:
          - $._environment.reporter.report($this, 'Cannot scale Pod up')


  recreatePod:
    Usage: Action
    Body:
      - $._environment.reporter.report($this, 'Recreating Pod {0}'.format($.name))
      - $.kubernetesCluster.deletePods(dict(id => $._getPodName()))
      - If: $.replicas = 0
        Then:
          - $._loadCurrentPodDefinition()
          - $.kubernetesCluster.createPod(definition => $._podDefinition, isNew => true)
      - $._environment.reporter.report($this, 'Pod {0} recreated'.format($.name))


  restartContainers:
    Usage: Action
    Body:
      - $.kubernetesCluster.restartContainers(podName => $._getPodName())