(function () {
  'use strict';

  var push = Array.prototype.push;
  var noop = angular.noop;

  /**
   * @ngdoc overview
   * @name horizon.dashboard.project.workflow.launch-instance
   *
   * @description
   * Manage workflow of creating server.
   */

  angular
    .module('horizon.dashboard.project.workflow.launch-instance')
    .factory('launchInstanceModel', launchInstanceModel);

  launchInstanceModel.$inject = [
    '$q',
    '$log',
    'horizon.app.core.openstack-service-api.cinder',
    'horizon.app.core.openstack-service-api.glance',
    'horizon.app.core.openstack-service-api.keystone',
    'horizon.app.core.openstack-service-api.neutron',
    'horizon.app.core.openstack-service-api.nova',
    'horizon.app.core.openstack-service-api.novaExtensions',
    'horizon.app.core.openstack-service-api.security-group',
    'horizon.app.core.openstack-service-api.serviceCatalog'
  ];

  /**
   * @ngdoc service
   * @name launchInstanceModel
   *
   * @description
   * This is the M part in MVC design pattern for launch instance
   * wizard workflow. It is responsible for providing data to the
   * view of each step in launch instance workflow and collecting
   * user's input from view for  creation of new instance.  It is
   * also the center point of communication between launch instance
   * UI and services API.
   */
  function launchInstanceModel(
    $q,
    $log,
    cinderAPI,
    glanceAPI,
    keystoneAPI,
    neutronAPI,
    novaAPI,
    novaExtensions,
    securityGroup,
    serviceCatalog
  ) {

    var initPromise;

    // Constants (const in ES6)
    var NON_BOOTABLE_IMAGE_TYPES = ['aki', 'ari'];
    var SOURCE_TYPE_IMAGE = 'image';
    var SOURCE_TYPE_SNAPSHOT = 'snapshot';
    var SOURCE_TYPE_VOLUME = 'volume';
    var SOURCE_TYPE_VOLUME_SNAPSHOT = 'volume_snapshot';

    /**
     * @ngdoc model api object
     */
    var model = {

      initializing: false,
      initialized: false,

      /*eslint-disable max-len */
      /**
       * @name newInstanceSpec
       *
       * @description
       * A dictionary like object containing specification collected from user's
       * input.  Its required properties include:
       *
       * @property {String} name: The new server name.
       * @property {String} source_type: The type of source
       *   Valid options: (image | snapshot | volume | volume_snapshot)
       * @property {String} source_id: The ID of the image / volume to use.
       * @property {String} flavor_id: The ID of the flavor to use.
       *
       * Other parameters are accepted as per the underlying novaclient:
       *  - https://github.com/openstack/python-novaclient/blob/master/novaclient/v2/servers.py#L417
       * But may be required additional values as per nova:
       *  - https://github.com/openstack/horizon/blob/master/openstack_dashboard/api/rest/nova.py#L127
       *
       * The JS code only needs to set the values below as they are made.
       * The createInstance function will map them appropriately.
       */
      /*eslint-enable max-len */

      // see initializeNewInstanceSpec
      newInstanceSpec: {},

      /**
       * cloud service properties, they should be READ-ONLY to all UI controllers
       */

      availabilityZones: [],
      flavors: [],
      allowedBootSources: [],
      images: [],
      allowCreateVolumeFromImage: false,
      arePortProfilesSupported: false,
      imageSnapshots: [],
      keypairs: [],
      metadataDefs: {
        flavor: null,
        image: null,
        volume: null
      },
      networks: [],
      neutronEnabled: false,
      novaLimits: {},
      profiles: [],
      securityGroups: [],
      volumeBootable: false,
      volumes: [],
      volumeSnapshots: [],

      /**
       * api methods for UI controllers
       */

      initialize: initialize,
      createInstance: createInstance
    };

    // Local function.
    function initializeNewInstanceSpec() {

      model.newInstanceSpec = {
        availability_zone: null,
        admin_pass: null,
        config_drive: false,
        // REQUIRED Server Key.  Null allowed.
        user_data: '',
        disk_config: 'AUTO',
        // REQUIRED
        flavor: null,
        instance_count: 1,
        // REQUIRED Server Key
        key_pair: [],
        // REQUIRED
        name: null,
        networks: [],
        profile: {},
        // REQUIRED Server Key. May be empty.
        security_groups: [],
        // REQUIRED for JS logic (image | snapshot | volume | volume_snapshot)
        source_type: null,
        source: [],
        // REQUIRED for JS logic
        vol_create: false,
        // May be null
        vol_device_name: 'vda',
        vol_delete_on_instance_delete: false,
        vol_size: 1
      };
    }

    /**
     * @ngdoc method
     * @name launchInstanceModel.initialize
     * @returns {promise}
     *
     * @description
     * Send request to get all data to initialize the model.
     */

    function initialize(deep) {
      var deferred, promise;

      // Each time opening launch instance wizard, we need to do this, or
      // we can call the whole methods `reset` instead of `initialize`.
      initializeNewInstanceSpec();

      if (model.initializing) {
        promise = initPromise;

      } else if (model.initialized && !deep) {
        deferred = $q.defer();
        promise = deferred.promise;
        deferred.resolve();

      } else {
        model.initializing = true;

        model.allowedBootSources.length = 0;

        promise = $q.all([
          getImages(),
          novaAPI.getAvailabilityZones().then(onGetAvailabilityZones, noop),
          novaAPI.getFlavors(true, true).then(onGetFlavors, noop),
          novaAPI.getKeypairs().then(onGetKeypairs, noop),
          novaAPI.getLimits().then(onGetNovaLimits, noop),
          securityGroup.query().then(onGetSecurityGroups, noop),
          serviceCatalog.ifTypeEnabled('network').then(getNetworks, noop),
          serviceCatalog.ifTypeEnabled('volume').then(getVolumes, noop)
        ]);

        promise.then(onInitSuccess, onInitFail);
      }

      return promise;
    }

    function onInitSuccess() {
      model.initializing = false;
      model.initialized = true;
      // This provides supplemental data non-critical to launching
      // an instance.  Therefore we load it only if the critical data
      // all loads successfully.
      getMetadataDefinitions();
    }

    function onInitFail() {
      model.initializing = false;
      model.initialized = false;
    }

    /**
     * @ngdoc method
     * @name launchInstanceModel.createInstance
     * @returns {promise}
     *
     * @description
     * Send request for creating server.
     */

    function createInstance() {
      var finalSpec = angular.copy(model.newInstanceSpec);

      cleanNullProperties(finalSpec);

      setFinalSpecBootsource(finalSpec);
      setFinalSpecFlavor(finalSpec);
      setFinalSpecNetworks(finalSpec);
      setFinalSpecKeyPairs(finalSpec);
      setFinalSpecSecurityGroups(finalSpec);

      return novaAPI.createServer(finalSpec);
    }

    function cleanNullProperties(finalSpec) {
      // Initially clean fields that don't have any value.
      for (var key in finalSpec) {
        if (finalSpec.hasOwnProperty(key) && finalSpec[key] === null) {
          delete finalSpec[key];
        }
      }
    }

    //
    // Local
    //

    function onGetAvailabilityZones(data) {
      model.availabilityZones.length = 0;
      push.apply(
        model.availabilityZones,
        data.data.items.filter(function (zone) {
                    return zone.zoneState && zone.zoneState.available;
                  })
                  .map(function (zone) {
                    return zone.zoneName;
                  })
                );

      if (model.availabilityZones.length > 0) {
        model.newInstanceSpec.availability_zone = model.availabilityZones[0];
      }
    }

    // Flavors

    function onGetFlavors(data) {
      model.flavors.length = 0;
      push.apply(model.flavors, data.data.items);
    }

    function setFinalSpecFlavor(finalSpec) {
      if ( finalSpec.flavor ) {
        finalSpec.flavor_id = finalSpec.flavor.id;
      } else {
        delete finalSpec.flavor_id;
      }

      delete finalSpec.flavor;
    }

    // Keypairs

    function onGetKeypairs(data) {
      angular.extend(
        model.keypairs,
        data.data.items.map(function (e) {
          e.keypair.id = e.keypair.name;
          return e.keypair;
        }));
    }

    function setFinalSpecKeyPairs(finalSpec) {
      // Nova only wants the key name. It is a required field, even if None.
      if (!finalSpec.key_name && finalSpec.key_pair.length === 1) {
        finalSpec.key_name = finalSpec.key_pair[0].name;
      } else if (!finalSpec.key_name) {
        finalSpec.key_name = null;
      }

      delete finalSpec.key_pair;
    }

    // Security Groups

    function onGetSecurityGroups(data) {
      model.securityGroups.length = 0;
      push.apply(model.securityGroups, data.data.items);
      // set initial default
      if (model.newInstanceSpec.security_groups.length === 0 &&
          model.securityGroups.length > 0) {
        model.securityGroups.forEach(function (securityGroup) {
          if (securityGroup.name === 'default') {
            model.newInstanceSpec.security_groups.push(securityGroup);
          }
        });
      }
    }

    function setFinalSpecSecurityGroups(finalSpec) {
      // pull out the ids from the security groups objects
      var securityGroupIds = [];
      finalSpec.security_groups.forEach(function(securityGroup) {
        if (model.neutronEnabled) {
          securityGroupIds.push(securityGroup.id);
        } else {
          securityGroupIds.push(securityGroup.name);
        }
      });
      finalSpec.security_groups = securityGroupIds;
    }

    // Networks

    function getNetworks() {
      return neutronAPI.getNetworks().then(onGetNetworks, noop);
    }

    function onGetNetworks(data) {
      model.neutronEnabled = true;
      model.networks.length = 0;
      push.apply(model.networks, data.data.items);
    }

    function setFinalSpecNetworks(finalSpec) {
      finalSpec.nics = [];
      finalSpec.networks.forEach(function (network) {
        finalSpec.nics.push(
          {
            "net-id": network.id,
            "v4-fixed-ip": ""
          });
      });
      delete finalSpec.networks;
    }

    // Boot Source

    function getImages() {
      return glanceAPI.getImages({status:'active'}).then(onGetImages);
    }

    function isBootableImageType(image) {
      // This is a blacklist of images that can not be booted.
      // If the image container type is in the blacklist
      // The evaluation will result in a 0 or greater index.
      return NON_BOOTABLE_IMAGE_TYPES.indexOf(image.container_format) < 0;
    }

    function onGetImages(data) {
      model.images.length = 0;
      push.apply(model.images, data.data.items.filter(function (image) {
        return isBootableImageType(image) &&
          (!image.properties || image.properties.image_type !== 'snapshot');
      }));
      addAllowedBootSource(model.images, SOURCE_TYPE_IMAGE, gettext('Image'));

      model.imageSnapshots.length = 0;
      push.apply(model.imageSnapshots, data.data.items.filter(function (image) {
        return isBootableImageType(image) &&
          (image.properties && image.properties.image_type === 'snapshot');
      }));

      addAllowedBootSource(
        model.imageSnapshots,
        SOURCE_TYPE_SNAPSHOT,
        gettext('Instance Snapshot')
      );
    }

    function getVolumes() {
      var volumePromises = [];
      // Need to check if Volume service is enabled before getting volumes
      model.volumeBootable = true;
      addAllowedBootSource(model.volumes, SOURCE_TYPE_VOLUME, gettext('Volume'));
      addAllowedBootSource(
        model.volumeSnapshots,
        SOURCE_TYPE_VOLUME_SNAPSHOT,
        gettext('Volume Snapshot')
      );
      volumePromises.push(cinderAPI.getVolumes({ status: 'available', bootable: 1 })
                          .then(onGetVolumes));
      volumePromises.push(cinderAPI.getVolumeSnapshots({ status: 'available' })
                          .then(onGetVolumeSnapshots));

      // Can only boot image to volume if the Nova extension is enabled.
      novaExtensions.ifNameEnabled('BlockDeviceMappingV2Boot')
        .then(function() { model.allowCreateVolumeFromImage = true; });

      return $q.all(volumePromises);
    }

    function onGetVolumes(data) {
      model.volumes.length = 0;
      push.apply(model.volumes, data.data.items);
    }

    function onGetVolumeSnapshots(data) {
      model.volumeSnapshots.length = 0;
      push.apply(model.volumeSnapshots, data.data.items);
    }

    function addAllowedBootSource(rawTypes, type, label) {
      if (rawTypes && rawTypes.length > 0) {
        model.allowedBootSources.push({
          type: type,
          label: label
        });
      }
    }

    function setFinalSpecBootsource(finalSpec) {
      finalSpec.source_id = finalSpec.source && finalSpec.source[0] && finalSpec.source[0].id;
      delete finalSpec.source;

      switch (finalSpec.source_type.type) {
        case SOURCE_TYPE_IMAGE:
          setFinalSpecBootImageToVolume(finalSpec);
          break;
        case SOURCE_TYPE_SNAPSHOT:
          break;
        case SOURCE_TYPE_VOLUME:
          setFinalSpecBootFromVolumeDevice(finalSpec, 'vol');
          break;
        case SOURCE_TYPE_VOLUME_SNAPSHOT:
          setFinalSpecBootFromVolumeDevice(finalSpec, 'snap');
          break;
        default:
          $log.error("Unknown source type: " + finalSpec.source_type);
      }

      // The following are all fields gathered into simple fields by
      // steps so that the view can simply bind to simple model attributes
      // that are then transformed a single time to Nova's expectation
      // at launch time.
      delete finalSpec.source_type;
      delete finalSpec.vol_create;
      delete finalSpec.vol_device_name;
      delete finalSpec.vol_delete_on_instance_delete;
      delete finalSpec.vol_size;
    }

    function setFinalSpecBootImageToVolume(finalSpec) {
      if (finalSpec.vol_create) {
        // Specify null to get Autoselection (not empty string)
        var deviceName = finalSpec.vol_device_name ? finalSpec.vol_device_name : null;
        finalSpec.block_device_mapping_v2 = [];
        finalSpec.block_device_mapping_v2.push(
          {
            'device_name': deviceName,
            'source_type': SOURCE_TYPE_IMAGE,
            'destination_type': SOURCE_TYPE_VOLUME,
            'delete_on_termination': finalSpec.vol_delete_on_instance_delete,
            'uuid': finalSpec.source_id,
            'boot_index': '0',
            'volume_size': finalSpec.vol_size
          }
        );
        finalSpec.source_id = null;
      }
    }

    function setFinalSpecBootFromVolumeDevice(finalSpec, sourceType) {
      finalSpec.block_device_mapping = {};
      finalSpec.block_device_mapping[finalSpec.vol_device_name] = [
        finalSpec.source_id,
        ':',
        sourceType,
        '::',
        finalSpec.vol_delete_on_instance_delete
      ].join('');

      // Source ID must be empty for API
      finalSpec.source_id = '';
    }

    // Nova Limits

    function onGetNovaLimits(data) {
      angular.extend(model.novaLimits, data.data);
    }

    // Metadata Definitions

    /**
     * Metadata definitions provide supplemental information in detail
     * rows and should not slow down any of the other load processes.
     * All code should be written to treat metadata definitions as
     * optional, because they are never guaranteed to exist.
     */
    function getMetadataDefinitions() {
      // Metadata definitions often apply to multiple
      // resource types. It is optimal to make a single
      // request for all desired resource types.
      var resourceTypes = {
        flavor: 'OS::Nova::Flavor',
        image: 'OS::Glance::Image',
        volume: 'OS::Cinder::Volumes'
      };

      angular.forEach(resourceTypes, applyForResourceType);
    }

    function applyForResourceType(resourceType, key) {
      glanceAPI
        .getNamespaces({'resource_type': resourceType}, true)
        .then(function(data) {
          var namespaces = data.data.items;
          // This will ensure that the metaDefs model object remains
          // unchanged until metadefs are fully loaded. Otherwise,
          // partial results are loaded and can result in some odd
          // display behavior.
          if (namespaces.length) {
            model.metadataDefs[key] = namespaces;
          }
        });
    }

    return model;
  }

})();