text: import ComputedProperty from '@ember/object/computed';
  import { setOwner } from '@ember/application';
  import { isNone } from '@ember/utils';
  import EmberError from '@ember/error';
  import Evented from '@ember/object/evented';
  import EmberObject, {
    computed,
    get,
    observer
  } from '@ember/object';
  import Map from '@ember/map';
  import Ember from 'ember';
  import { DEBUG } from '@glimmer/env';
  import { assert, deprecate, warn } from '@ember/debug';
  import { PromiseObject } from "../promise-proxies";
  import Errors from "../model/errors";
  import isEnabled from '../../features';
  import RootState from '../model/states';
  import {
    relationshipsByNameDescriptor,
    relatedTypesDescriptor,
    relationshipsDescriptor
  } from '../relationships/ext';
  
  /**
    @module ember-data
  */
  
  function findPossibleInverses(type, inverseType, name, relationshipsSoFar) {
    let possibleRelationships = relationshipsSoFar || [];
  
    let relationshipMap = get(inverseType, 'relationships');
    if (!relationshipMap) { return possibleRelationships; }
  
    let relationships = relationshipMap.get(type.modelName).filter(relationship => {
      let optionsForRelationship = inverseType.metaForProperty(relationship.name).options;
  
      if (!optionsForRelationship.inverse) {
        return true;
      }
  
      return name === optionsForRelationship.inverse;
    });
  
    if (relationships) {
      possibleRelationships.push.apply(possibleRelationships, relationships);
    }
  
    //Recurse to support polymorphism
    if (type.superclass) {
      findPossibleInverses(type.superclass, inverseType, name, possibleRelationships);
    }
  
    return possibleRelationships;
  }
  
  function intersection (array1, array2) {
    let result = [];
    array1.forEach((element) => {
      if (array2.indexOf(element) >= 0) {
        result.push(element);
      }
    });
  
    return result;
  }
  
  const RESERVED_MODEL_PROPS = [
    'currentState', 'data', 'store'
  ];
  
  const retrieveFromCurrentState = computed('currentState', function(key) {
    return get(this._internalModel.currentState, key);
  }).readOnly();
  
  /**
  
    The model class that all Ember Data records descend from.
    This is the public API of Ember Data models. If you are using Ember Data
    in your application, this is the class you should use.
    If you are working on Ember Data internals, you most likely want to be dealing
    with `InternalModel`
  
    @class Model
    @namespace DS
    @extends Ember.Object
    @uses Ember.Evented
  */
  const Model = EmberObject.extend(Evented, {
    _internalModel: null,
    store: null,
    __defineNonEnumerable(property) {
      this[property.name] = property.descriptor.value;
    },
  
    /**
      If this property is `true` the record is in the `empty`
      state. Empty is the first state all records enter after they have
      been created. Most records created by the store will quickly
      transition to the `loading` state if data needs to be fetched from
      the server or the `created` state if the record is created on the
      client. A record can also enter the empty state if the adapter is
      unable to locate the record.
  
      @property isEmpty
      @type {Boolean}
      @readOnly
    */
    isEmpty: retrieveFromCurrentState,
    /**
      If this property is `true` the record is in the `loading` state. A
      record enters this state when the store asks the adapter for its
      data. It remains in this state until the adapter provides the
      requested data.
  
      @property isLoading
      @type {Boolean}
      @readOnly
    */
    isLoading: retrieveFromCurrentState,
    /**
      If this property is `true` the record is in the `loaded` state. A
      record enters this state when its data is populated. Most of a
      record's lifecycle is spent inside substates of the `loaded`
      state.
  
      Example
  
      ```javascript
      let record = store.createRecord('model');
      record.get('isLoaded'); // true
  
      store.findRecord('model', 1).then(function(model) {
        model.get('isLoaded'); // true
      });
      ```
  
      @property isLoaded
      @type {Boolean}
      @readOnly
    */
    isLoaded: retrieveFromCurrentState,
    /**
      If this property is `true` the record is in the `dirty` state. The
      record has local changes that have not yet been saved by the
      adapter. This includes records that have been created (but not yet
      saved) or deleted.
  
      Example
  
      ```javascript
      let record = store.createRecord('model');
      record.get('hasDirtyAttributes'); // true
  
      store.findRecord('model', 1).then(function(model) {
        model.get('hasDirtyAttributes'); // false
        model.set('foo', 'some value');
        model.get('hasDirtyAttributes'); // true
      });
      ```
  
      @since 1.13.0
      @property hasDirtyAttributes
      @type {Boolean}
      @readOnly
    */
    hasDirtyAttributes: computed('currentState.isDirty', function() {
      return this.get('currentState.isDirty');
    }),
    /**
      If this property is `true` the record is in the `saving` state. A
      record enters the saving state when `save` is called, but the
      adapter has not yet acknowledged that the changes have been
      persisted to the backend.
  
      Example
  
      ```javascript
      let record = store.createRecord('model');
      record.get('isSaving'); // false
      let promise = record.save();
      record.get('isSaving'); // true
      promise.then(function() {
        record.get('isSaving'); // false
      });
      ```
  
      @property isSaving
      @type {Boolean}
      @readOnly
    */
    isSaving: retrieveFromCurrentState,
    /**
      If this property is `true` the record is in the `deleted` state
      and has been marked for deletion. When `isDeleted` is true and
      `hasDirtyAttributes` is true, the record is deleted locally but the deletion
      was not yet persisted. When `isSaving` is true, the change is
      in-flight. When both `hasDirtyAttributes` and `isSaving` are false, the
      change has persisted.
  
      Example
  
      ```javascript
      let record = store.createRecord('model');
      record.get('isDeleted');    // false
      record.deleteRecord();
  
      // Locally deleted
      record.get('isDeleted');           // true
      record.get('hasDirtyAttributes');  // true
      record.get('isSaving');            // false
  
      // Persisting the deletion
      let promise = record.save();
      record.get('isDeleted');    // true
      record.get('isSaving');     // true
  
      // Deletion Persisted
      promise.then(function() {
        record.get('isDeleted');          // true
        record.get('isSaving');           // false
        record.get('hasDirtyAttributes'); // false
      });
      ```
  
      @property isDeleted
      @type {Boolean}
      @readOnly
    */
    isDeleted: retrieveFromCurrentState,
    /**
      If this property is `true` the record is in the `new` state. A
      record will be in the `new` state when it has been created on the
      client and the adapter has not yet report that it was successfully
      saved.
  
      Example
  
      ```javascript
      let record = store.createRecord('model');
      record.get('isNew'); // true
  
      record.save().then(function(model) {
        model.get('isNew'); // false
      });
      ```
  
      @property isNew
      @type {Boolean}
      @readOnly
    */
    isNew: retrieveFromCurrentState,
    /**
      If this property is `true` the record is in the `valid` state.
  
      A record will be in the `valid` state when the adapter did not report any
      server-side validation failures.
  
      @property isValid
      @type {Boolean}
      @readOnly
    */
    isValid: retrieveFromCurrentState,
    /**
      If the record is in the dirty state this property will report what
      kind of change has caused it to move into the dirty
      state. Possible values are:
  
      - `created` The record has been created by the client and not yet saved to the adapter.
      - `updated` The record has been updated by the client and not yet saved to the adapter.
      - `deleted` The record has been deleted by the client and not yet saved to the adapter.
  
      Example
  
      ```javascript
      let record = store.createRecord('model');
      record.get('dirtyType'); // 'created'
      ```
  
      @property dirtyType
      @type {String}
      @readOnly
    */
    dirtyType: retrieveFromCurrentState,
  
    /**
      If `true` the adapter reported that it was unable to save local
      changes to the backend for any reason other than a server-side
      validation error.
  
      Example
  
      ```javascript
      record.get('isError'); // false
      record.set('foo', 'valid value');
      record.save().then(null, function() {
        record.get('isError'); // true
      });
      ```
  
      @property isError
      @type {Boolean}
      @readOnly
    */
    isError: false,
  
    /**
      If `true` the store is attempting to reload the record from the adapter.
  
      Example
  
      ```javascript
      record.get('isReloading'); // false
      record.reload();
      record.get('isReloading'); // true
      ```
  
      @property isReloading
      @type {Boolean}
      @readOnly
    */
    isReloading: false,
  
    /**
      All ember models have an id property. This is an identifier
      managed by an external source. These are always coerced to be
      strings before being used internally. Note when declaring the
      attributes for a model it is an error to declare an id
      attribute.
  
      ```javascript
      let record = store.createRecord('model');
      record.get('id'); // null
  
      store.findRecord('model', 1).then(function(model) {
        model.get('id'); // '1'
      });
      ```
  
      @property id
      @type {String}
    */
    id: null,
  
    /**
      @property currentState
      @private
      @type {Object}
    */
    currentState: RootState.empty,
  
    /**
      When the record is in the `invalid` state this object will contain
      any errors returned by the adapter. When present the errors hash
      contains keys corresponding to the invalid property names
      and values which are arrays of Javascript objects with two keys:
  
      - `message` A string containing the error message from the backend
      - `attribute` The name of the property associated with this error message
  
      ```javascript
      record.get('errors.length'); // 0
      record.set('foo', 'invalid value');
      record.save().catch(function() {
        record.get('errors').get('foo');
        // [{message: 'foo should be a number.', attribute: 'foo'}]
      });
      ```
  
      The `errors` property us useful for displaying error messages to
      the user.
  
      ```handlebars
      <label>Username: {{input value=username}} </label>
      {{#each model.errors.username as |error|}}
        <div class="error">
          {{error.message}}
        </div>
      {{/each}}
      <label>Email: {{input value=email}} </label>
      {{#each model.errors.email as |error|}}
        <div class="error">
          {{error.message}}
        </div>
      {{/each}}
      ```
  
  
      You can also access the special `messages` property on the error
      object to get an array of all the error strings.
  
      ```handlebars
      {{#each model.errors.messages as |message|}}
        <div class="error">
          {{message}}
        </div>
      {{/each}}
      ```
  
      @property errors
      @type {DS.Errors}
    */
    errors: computed(function() {
      let errors = Errors.create();
  
      errors._registerHandlers(this._internalModel,
        function() {
          this.send('becameInvalid');
        },
        function() {
          this.send('becameValid');
        });
      return errors;
    }).readOnly(),
  
    /**
      This property holds the `DS.AdapterError` object with which
      last adapter operation was rejected.
  
      @property adapterError
      @type {DS.AdapterError}
    */
    adapterError: null,
  
    /**
      Create a JSON representation of the record, using the serialization
      strategy of the store's adapter.
  
     `serialize` takes an optional hash as a parameter, currently
      supported options are:
  
     - `includeId`: `true` if the record's ID should be included in the
        JSON representation.
  
      @method serialize
      @param {Object} options
      @return {Object} an object whose values are primitive JSON values only
    */
    serialize(options) {
      return this._internalModel.createSnapshot().serialize(options);
    },
  
    /**
      Use [DS.JSONSerializer](DS.JSONSerializer.html) to
      get the JSON representation of a record.
  
      `toJSON` takes an optional hash as a parameter, currently
      supported options are:
  
      - `includeId`: `true` if the record's ID should be included in the
        JSON representation.
  
      @method toJSON
      @param {Object} options
      @return {Object} A JSON representation of the object.
    */
    toJSON(options) {
      // container is for lazy transform lookups
      let serializer = this.store.serializerFor('-default');
      let snapshot = this._internalModel.createSnapshot();
  
      return serializer.serialize(snapshot, options);
    },
  
    /**
      Fired when the record is ready to be interacted with,
      that is either loaded from the server or created locally.
  
      @event ready
    */
    ready: null,
  
    /**
      Fired when the record is loaded from the server.
  
      @event didLoad
    */
    didLoad: null,
  
    /**
      Fired when the record is updated.
  
      @event didUpdate
    */
    didUpdate: null,
  
    /**
      Fired when a new record is commited to the server.
  
      @event didCreate
    */
    didCreate: null,
  
    /**
      Fired when the record is deleted.
  
      @event didDelete
    */
    didDelete: null,
  
    /**
      Fired when the record becomes invalid.
  
      @event becameInvalid
    */
    becameInvalid: null,
  
    /**
      Fired when the record enters the error state.
  
      @event becameError
    */
    becameError: null,
  
    /**
      Fired when the record is rolled back.
  
      @event rolledBack
    */
    rolledBack: null,
  
    //TODO Do we want to deprecate these?
    /**
      @method send
      @private
      @param {String} name
      @param {Object} context
    */
    send(name, context) {
      return this._internalModel.send(name, context);
    },
  
    /**
      @method transitionTo
      @private
      @param {String} name
    */
    transitionTo(name) {
      return this._internalModel.transitionTo(name);
    },
  
  
    /**
      Marks the record as deleted but does not save it. You must call
      `save` afterwards if you want to persist it. You might use this
      method if you want to allow the user to still `rollbackAttributes()`
      after a delete was made.
  
      Example
  
      ```app/routes/model/delete.js
      import Route from '@ember/routing/route';
  
      export default Route.extend({
        actions: {
          softDelete() {
            this.get('controller.model').deleteRecord();
          },
          confirm() {
            this.get('controller.model').save();
          },
          undo() {
            this.get('controller.model').rollbackAttributes();
          }
        }
      });
      ```
  
      @method deleteRecord
    */
    deleteRecord() {
      this._internalModel.deleteRecord();
    },
  
    /**
      Same as `deleteRecord`, but saves the record immediately.
  
      Example
  
      ```app/routes/model/delete.js
      import Route from '@ember/routing/route';
  
      export default Route.extend({
        actions: {
          delete() {
            this.get('controller.model').destroyRecord().then(function() {
              controller.transitionToRoute('model.index');
            });
          }
        }
      });
      ```
  
      If you pass an object on the `adapterOptions` property of the options
      argument it will be passed to your adapter via the snapshot
  
      ```js
      record.destroyRecord({ adapterOptions: { subscribe: false } });
      ```
  
      ```app/adapters/post.js
      import MyCustomAdapter from './custom-adapter';
  
      export default MyCustomAdapter.extend({
        deleteRecord(store, type, snapshot) {
          if (snapshot.adapterOptions.subscribe) {
            // ...
          }
          // ...
        }
      });
      ```
  
      @method destroyRecord
      @param {Object} options
      @return {Promise} a promise that will be resolved when the adapter returns
      successfully or rejected if the adapter returns with an error.
    */
    destroyRecord(options) {
      this.deleteRecord();
      return this.save(options);
    },
  
    /**
      Unloads the record from the store. This will cause the record to be destroyed and freed up for garbage collection.
  
      @method unloadRecord
    */
    unloadRecord() {
      if (this.isDestroyed) { return; }
      this._internalModel.unloadRecord();
    },
  
    /**
      @method _notifyProperties
      @private
    */
    _notifyProperties(keys) {
      Ember.beginPropertyChanges();
      let key;
      for (let i = 0, length = keys.length; i < length; i++) {
        key = keys[i];
        this.notifyPropertyChange(key);
      }
      Ember.endPropertyChanges();
    },
  
    /**
      Returns an object, whose keys are changed properties, and value is
      an [oldProp, newProp] array.
  
      The array represents the diff of the canonical state with the local state
      of the model. Note: if the model is created locally, the canonical state is
      empty since the adapter hasn't acknowledged the attributes yet:
  
      Example
  
      ```app/models/mascot.js
      import DS from 'ember-data';
  
      export default DS.Model.extend({
        name: DS.attr('string'),
        isAdmin: DS.attr('boolean', {
          defaultValue: false
        })
      });
      ```
  
      ```javascript
      let mascot = store.createRecord('mascot');
  
      mascot.changedAttributes(); // {}
  
      mascot.set('name', 'Tomster');
      mascot.changedAttributes(); // { name: [undefined, 'Tomster'] }
  
      mascot.set('isAdmin', true);
      mascot.changedAttributes(); // { isAdmin: [undefined, true], name: [undefined, 'Tomster'] }
  
      mascot.save().then(function() {
        mascot.changedAttributes(); // {}
  
        mascot.set('isAdmin', false);
        mascot.changedAttributes(); // { isAdmin: [true, false] }
      });
      ```
  
      @method changedAttributes
      @return {Object} an object, whose keys are changed properties,
        and value is an [oldProp, newProp] array.
    */
    changedAttributes() {
      return this._internalModel.changedAttributes();
    },
  
    //TODO discuss with tomhuda about events/hooks
    //Bring back as hooks?
    /**
      @method adapterWillCommit
      @private
    adapterWillCommit: function() {
      this.send('willCommit');
    },
  
    /**
      @method adapterDidDirty
      @private
    adapterDidDirty: function() {
      this.send('becomeDirty');
      this.updateRecordArraysLater();
    },
    */
  
    /**
      If the model `hasDirtyAttributes` this function will discard any unsaved
      changes. If the model `isNew` it will be removed from the store.
  
      Example
  
      ```javascript
      record.get('name'); // 'Untitled Document'
      record.set('name', 'Doc 1');
      record.get('name'); // 'Doc 1'
      record.rollbackAttributes();
      record.get('name'); // 'Untitled Document'
      ```
  
      @since 1.13.0
      @method rollbackAttributes
    */
    rollbackAttributes() {
      this._internalModel.rollbackAttributes();
    },
  
    /*
      @method _createSnapshot
      @private
    */
    _createSnapshot() {
      return this._internalModel.createSnapshot();
    },
  
    toStringExtension() {
      return get(this, 'id');
    },
  
    /**
      Save the record and persist any changes to the record to an
      external source via the adapter.
  
      Example
  
      ```javascript
      record.set('name', 'Tomster');
      record.save().then(function() {
        // Success callback
      }, function() {
        // Error callback
      });
      ```
  
     If you pass an object using the `adapterOptions` property of the options
     argument it will be passed to your adapter via the snapshot.
  
      ```js
      record.save({ adapterOptions: { subscribe: false } });
      ```
  
      ```app/adapters/post.js
      import MyCustomAdapter from './custom-adapter';
  
      export default MyCustomAdapter.extend({
        updateRecord(store, type, snapshot) {
          if (snapshot.adapterOptions.subscribe) {
            // ...
          }
          // ...
        }
      });
      ```
  
      @method save
      @param {Object} options
      @return {Promise} a promise that will be resolved when the adapter returns
      successfully or rejected if the adapter returns with an error.
    */
    save(options) {
      return PromiseObject.create({
        promise: this._internalModel.save(options).then(() => this)
      });
    },
  
    /**
      Reload the record from the adapter.
  
      This will only work if the record has already finished loading.
  
      Example
  
      ```app/routes/model/view.js
      import Route from '@ember/routing/route';
  
      export default Route.extend({
        actions: {
          reload() {
            this.controller.get('model').reload().then(function(model) {
              // do something with the reloaded model
            });
          }
        }
      });
      ```
  
      @method reload
      @return {Promise} a promise that will be resolved with the record when the
      adapter returns successfully or rejected if the adapter returns
      with an error.
    */
    reload() {
      return PromiseObject.create({
        promise: this._internalModel.reload().then(() => this)
      });
    },
  
  
    /**
      Override the default event firing from Ember.Evented to
      also call methods with the given name.
  
      @method trigger
      @private
      @param {String} name
    */
    trigger(name) {
      let fn = this[name];
  
      if (typeof fn === 'function') {
        let length = arguments.length;
        let args = new Array(length - 1);
  
        for (let i = 1; i < length; i++) {
          args[i - 1] = arguments[i];
        }
        fn.apply(this, args)
      }
  
      this._super(...arguments);
    },
  
    attr() {
      assert("The `attr` method is not available on DS.Model, a DS.Snapshot was probably expected. Are you passing a DS.Model instead of a DS.Snapshot to your serializer?", false);
    },
  
    /**
      Get the reference for the specified belongsTo relationship.
  
      Example
  
      ```app/models/blog.js
      export default DS.Model.extend({
        user: DS.belongsTo({ async: true })
      });
      ```
  
      ```javascript
      let blog = store.push({
        data: {
          type: 'blog',
          id: 1,
          relationships: {
            user: {
              data: { type: 'user', id: 1 }
            }
          }
        }
      });
      let userRef = blog.belongsTo('user');
  
      // check if the user relationship is loaded
      let isLoaded = userRef.value() !== null;
  
      // get the record of the reference (null if not yet available)
      let user = userRef.value();
  
      // get the identifier of the reference
      if (userRef.remoteType() === "id") {
        let id = userRef.id();
      } else if (userRef.remoteType() === "link") {
        let link = userRef.link();
      }
  
      // load user (via store.findRecord or store.findBelongsTo)
      userRef.load().then(...)
  
      // or trigger a reload
      userRef.reload().then(...)
  
      // provide data for reference
      userRef.push({
        type: 'user',
        id: 1,
        attributes: {
          username: "@user"
        }
      }).then(function(user) {
        userRef.value() === user;
      });
      ```
  
      @method belongsTo
      @param {String} name of the relationship
      @since 2.5.0
      @return {BelongsToReference} reference for this relationship
    */
    belongsTo(name) {
      return this._internalModel.referenceFor('belongsTo', name);
    },
  
    /**
      Get the reference for the specified hasMany relationship.
  
      Example
  
      ```javascript
      // models/blog.js
      export default DS.Model.extend({
        comments: DS.hasMany({ async: true })
      });
  
      let blog = store.push({
        data: {
          type: 'blog',
          id: 1,
          relationships: {
            comments: {
              data: [
                { type: 'comment', id: 1 },
                { type: 'comment', id: 2 }
              ]
            }
          }
        }
      });
      let commentsRef = blog.hasMany('comments');
  
      // check if the comments are loaded already
      let isLoaded = commentsRef.value() !== null;
  
      // get the records of the reference (null if not yet available)
      let comments = commentsRef.value();
  
      // get the identifier of the reference
      if (commentsRef.remoteType() === "ids") {
        let ids = commentsRef.ids();
      } else if (commentsRef.remoteType() === "link") {
        let link = commentsRef.link();
      }
  
      // load comments (via store.findMany or store.findHasMany)
      commentsRef.load().then(...)
  
      // or trigger a reload
      commentsRef.reload().then(...)
  
      // provide data for reference
      commentsRef.push([{ type: 'comment', id: 1 }, { type: 'comment', id: 2 }]).then(function(comments) {
        commentsRef.value() === comments;
      });
      ```
  
      @method hasMany
      @param {String} name of the relationship
      @since 2.5.0
      @return {HasManyReference} reference for this relationship
    */
    hasMany(name) {
      return this._internalModel.referenceFor('hasMany', name);
    },
  
    setId: observer('id', function () {
      this._internalModel.setId(this.get('id'));
    }),
  
    /**
     Provides info about the model for debugging purposes
     by grouping the properties into more semantic groups.
  
     Meant to be used by debugging tools such as the Chrome Ember Extension.
  
     - Groups all attributes in "Attributes" group.
     - Groups all belongsTo relationships in "Belongs To" group.
     - Groups all hasMany relationships in "Has Many" group.
     - Groups all flags in "Flags" group.
     - Flags relationship CPs as expensive properties.
  
     @method _debugInfo
     @for DS.Model
     @private
     */
    _debugInfo() {
      let attributes = ['id'];
      let relationships = { };
      let expensiveProperties = [];
  
      this.eachAttribute((name, meta) => attributes.push(name));
  
      let groups = [
        {
          name: 'Attributes',
          properties: attributes,
          expand: true
        }
      ];
  
      this.eachRelationship((name, relationship) => {
        let properties = relationships[relationship.kind];
  
        if (properties === undefined) {
          properties = relationships[relationship.kind] = [];
          groups.push({
            name: relationship.name,
            properties,
            expand: true
          });
        }
        properties.push(name);
        expensiveProperties.push(name);
      });
  
      groups.push({
        name: 'Flags',
        properties: ['isLoaded', 'hasDirtyAttributes', 'isSaving', 'isDeleted', 'isError', 'isNew', 'isValid']
      });
  
      return {
        propertyInfo: {
          // include all other mixins / properties (not just the grouped ones)
          includeOtherProperties: true,
          groups: groups,
          // don't pre-calculate unless cached
          expensiveProperties: expensiveProperties
        }
      };
    },
  
    notifyBelongsToChanged(key) {
      this.notifyPropertyChange(key);
    },
    /**
     Given a callback, iterates over each of the relationships in the model,
     invoking the callback with the name of each relationship and its relationship
     descriptor.
  
  
     The callback method you provide should have the following signature (all
     parameters are optional):
  
     ```javascript
     function(name, descriptor);
     ```
  
     - `name` the name of the current property in the iteration
     - `descriptor` the meta object that describes this relationship
  
     The relationship descriptor argument is an object with the following properties.
  
     - **key** <span class="type">String</span> the name of this relationship on the Model
     - **kind** <span class="type">String</span> "hasMany" or "belongsTo"
     - **options** <span class="type">Object</span> the original options hash passed when the relationship was declared
     - **parentType** <span class="type">DS.Model</span> the type of the Model that owns this relationship
     - **type** <span class="type">String</span> the type name of the related Model
  
     Note that in addition to a callback, you can also pass an optional target
     object that will be set as `this` on the context.
  
     Example
  
     ```app/serializers/application.js
     import DS from 'ember-data';
  
     export default DS.JSONSerializer.extend({
      serialize: function(record, options) {
        let json = {};
  
        record.eachRelationship(function(name, descriptor) {
          if (descriptor.kind === 'hasMany') {
            let serializedHasManyName = name.toUpperCase() + '_IDS';
            json[serializedHasManyName] = record.get(name).mapBy('id');
          }
        });
  
        return json;
      }
    });
     ```
  
     @method eachRelationship
     @param {Function} callback the callback to invoke
     @param {any} binding the value to which the callback's `this` should be bound
     */
    eachRelationship(callback, binding) {
      this.constructor.eachRelationship(callback, binding);
    },
  
    relationshipFor(name) {
      return get(this.constructor, 'relationshipsByName').get(name);
    },
  
    inverseFor(key) {
      return this.constructor.inverseFor(key, this.store);
    },
  
    notifyHasManyAdded(key) {
      //We need to notifyPropertyChange in the adding case because we need to make sure
      //we fetch the newly added record in case it is unloaded
      //TODO(Igor): Consider whether we could do this only if the record state is unloaded
  
      //Goes away once hasMany is double promisified
      this.notifyPropertyChange(key);
    },
  
    eachAttribute(callback, binding) {
      this.constructor.eachAttribute(callback, binding);
    }
  });
  
  /**
   @property data
   @private
   @type {Object}
   */
  Object.defineProperty(Model.prototype, 'data', {
    get() {
      return this._internalModel._data;
    }
  });
  
  if (DEBUG) {
    Model.reopen({
      init() {
        this._super(...arguments);
  
        if (!this._internalModel) {
          throw new EmberError('You should not call `create` on a model. Instead, call `store.createRecord` with the attributes you would like to set.');
        }
      }
    });
  }
  
  Model.reopenClass({
    isModel: true,
  
    /**
      Override the class' `create()` method to raise an error. This
      prevents end users from inadvertently calling `create()` instead
      of `createRecord()`. The store is still able to create instances
      by calling the `_create()` method. To create an instance of a
      `DS.Model` use [store.createRecord](DS.Store.html#method_createRecord).
  
      @method create
      @private
      @static
    */
    /**
     Represents the model's class name as a string. This can be used to look up the model's class name through
     `DS.Store`'s modelFor method.
  
     `modelName` is generated for you by Ember Data. It will be a lowercased, dasherized string.
     For example:
  
     ```javascript
     store.modelFor('post').modelName; // 'post'
     store.modelFor('blog-post').modelName; // 'blog-post'
     ```
  
     The most common place you'll want to access `modelName` is in your serializer's `payloadKeyFromModelName` method. For example, to change payload
     keys to underscore (instead of dasherized), you might use the following code:
  
     ```javascript
     import { underscore } from '@ember/string';
  
     export default const PostSerializer = DS.RESTSerializer.extend({
       payloadKeyFromModelName(modelName) {
         return underscore(modelName);
       }
     });
     ```
     @property modelName
     @type String
     @readonly
     @static
    */
    modelName: null,
  
    /*
     These class methods below provide relationship
     introspection abilities about relationships.
  
     A note about the computed properties contained here:
  
     **These properties are effectively sealed once called for the first time.**
     To avoid repeatedly doing expensive iteration over a model's fields, these
     values are computed once and then cached for the remainder of the runtime of
     your application.
  
     If your application needs to modify a class after its initial definition
     (for example, using `reopen()` to add additional attributes), make sure you
     do it before using your model with the store, which uses these properties
     extensively.
     */
  
    /**
     For a given relationship name, returns the model type of the relationship.
  
     For example, if you define a model like this:
  
     ```app/models/post.js
     import DS from 'ember-data';
  
     export default DS.Model.extend({
        comments: DS.hasMany('comment')
      });
     ```
  
     Calling `store.modelFor('post').typeForRelationship('comments', store)` will return `Comment`.
  
     @method typeForRelationship
     @static
     @param {String} name the name of the relationship
     @param {store} store an instance of DS.Store
     @return {DS.Model} the type of the relationship, or undefined
     */
    typeForRelationship(name, store) {
      let relationship = get(this, 'relationshipsByName').get(name);
      return relationship && store.modelFor(relationship.type);
    },
  
    inverseMap: computed(function() {
      return Object.create(null);
    }),
  
    /**
     Find the relationship which is the inverse of the one asked for.
  
     For example, if you define models like this:
  
     ```app/models/post.js
     import DS from 'ember-data';
  
     export default DS.Model.extend({
        comments: DS.hasMany('message')
      });
     ```
  
     ```app/models/message.js
     import DS from 'ember-data';
  
     export default DS.Model.extend({
        owner: DS.belongsTo('post')
      });
     ```
  
     ``` js
     store.modelFor('post').inverseFor('comments', store) // { type: App.Message, name: 'owner', kind: 'belongsTo' }
     store.modelFor('message').inverseFor('owner', store) // { type: App.Post, name: 'comments', kind: 'hasMany' }
     ```
  
     @method inverseFor
     @static
     @param {String} name the name of the relationship
     @param {DS.Store} store
     @return {Object} the inverse relationship, or null
     */
    inverseFor(name, store) {
      let inverseMap = get(this, 'inverseMap');
      if (inverseMap[name] !== undefined) {
        return inverseMap[name];
      } else {
        let relationship = get(this, 'relationshipsByName').get(name);
        if (!relationship) {
          inverseMap[name] = null;
          return null;
        }
  
        let options = relationship.options;
        if (options && options.inverse === null) {
          // populate the cache with a miss entry so we can skip getting and going
          // through `relationshipsByName`
          inverseMap[name] = null;
          return null;
        }
  
        return inverseMap[name] = this._findInverseFor(name, store);
      }
    },
  
    //Calculate the inverse, ignoring the cache
    _findInverseFor(name, store) {
  
      let inverseType = this.typeForRelationship(name, store);
      if (!inverseType) {
        return null;
      }
  
      let propertyMeta = this.metaForProperty(name);
      //If inverse is manually specified to be null, like  `comments: DS.hasMany('message', { inverse: null })`
      let options = propertyMeta.options;
      if (options.inverse === null) { return null; }
  
      let inverseName, inverseKind, inverse;
  
      //If inverse is specified manually, return the inverse
      if (options.inverse) {
        inverseName = options.inverse;
        inverse = get(inverseType, 'relationshipsByName').get(inverseName);
  
        assert("We found no inverse relationships by the name of '" + inverseName + "' on the '" + inverseType.modelName +
          "' model. This is most likely due to a missing attribute on your model definition.", !isNone(inverse));
  
        inverseKind = inverse.kind;
      } else {
        //No inverse was specified manually, we need to use a heuristic to guess one
        if (propertyMeta.parentType && propertyMeta.type === propertyMeta.parentType.modelName) {
          warn(`Detected a reflexive relationship by the name of '${name}' without an inverse option. Look at https://emberjs.com/guides/models/defining-models/#toc_reflexive-relation for how to explicitly specify inverses.`, false, {
            id: 'ds.model.reflexive-relationship-without-inverse'
          });
        }
  
        let possibleRelationships = findPossibleInverses(this, inverseType, name);
  
        if (possibleRelationships.length === 0) { return null; }
  
        let filteredRelationships = possibleRelationships.filter((possibleRelationship) => {
          let optionsForRelationship = inverseType.metaForProperty(possibleRelationship.name).options;
          return name === optionsForRelationship.inverse;
        });
  
        assert("You defined the '" + name + "' relationship on " + this + ", but you defined the inverse relationships of type " +
          inverseType.toString() + " multiple times. Look at https://emberjs.com/guides/models/defining-models/#toc_explicit-inverses for how to explicitly specify inverses",
          filteredRelationships.length < 2);
  
        if (filteredRelationships.length === 1 ) {
          possibleRelationships = filteredRelationships;
        }
  
        assert("You defined the '" + name + "' relationship on " + this + ", but multiple possible inverse relationships of type " +
          this + " were found on " + inverseType + ". Look at https://emberjs.com/guides/models/defining-models/#toc_explicit-inverses for how to explicitly specify inverses",
          possibleRelationships.length === 1);
  
        inverseName = possibleRelationships[0].name;
        inverseKind = possibleRelationships[0].kind;
      }
  
      return {
        type: inverseType,
        name: inverseName,
        kind: inverseKind
      };
    },
  
    /**
     The model's relationships as a map, keyed on the type of the
     relationship. The value of each entry is an array containing a descriptor
     for each relationship with that type, describing the name of the relationship
     as well as the type.
  
     For example, given the following model definition:
  
     ```app/models/blog.js
     import DS from 'ember-data';
  
     export default DS.Model.extend({
        users: DS.hasMany('user'),
        owner: DS.belongsTo('user'),
        posts: DS.hasMany('post')
      });
     ```
  
     This computed property would return a map describing these
     relationships, like this:
  
     ```javascript
     import Ember from 'ember';
     import Blog from 'app/models/blog';
     import User from 'app/models/user';
     import Post from 'app/models/post';
  
     let relationships = Ember.get(Blog, 'relationships');
     relationships.get(User);
     //=> [ { name: 'users', kind: 'hasMany' },
     //     { name: 'owner', kind: 'belongsTo' } ]
     relationships.get(Post);
     //=> [ { name: 'posts', kind: 'hasMany' } ]
     ```
  
     @property relationships
     @static
     @type Ember.Map
     @readOnly
     */
  
    relationships: relationshipsDescriptor,
  
    /**
     A hash containing lists of the model's relationships, grouped
     by the relationship kind. For example, given a model with this
     definition:
  
     ```app/models/blog.js
     import DS from 'ember-data';
  
     export default DS.Model.extend({
        users: DS.hasMany('user'),
        owner: DS.belongsTo('user'),
  
        posts: DS.hasMany('post')
      });
     ```
  
     This property would contain the following:
  
     ```javascript
     import Ember from 'ember';
     import Blog from 'app/models/blog';
  
     let relationshipNames = Ember.get(Blog, 'relationshipNames');
     relationshipNames.hasMany;
     //=> ['users', 'posts']
     relationshipNames.belongsTo;
     //=> ['owner']
     ```
  
     @property relationshipNames
     @static
     @type Object
     @readOnly
     */
    relationshipNames: computed(function() {
      let names = {
        hasMany: [],
        belongsTo: []
      };
  
      this.eachComputedProperty((name, meta) => {
        if (meta.isRelationship) {
          names[meta.kind].push(name);
        }
      });
  
      return names;
    }),
  
    /**
     An array of types directly related to a model. Each type will be
     included once, regardless of the number of relationships it has with
     the model.
  
     For example, given a model with this definition:
  
     ```app/models/blog.js
     import DS from 'ember-data';
  
     export default DS.Model.extend({
        users: DS.hasMany('user'),
        owner: DS.belongsTo('user'),
  
        posts: DS.hasMany('post')
      });
     ```
  
     This property would contain the following:
  
     ```javascript
     import Ember from 'ember';
     import Blog from 'app/models/blog';
  
     let relatedTypes = Ember.get(Blog, 'relatedTypes');
     //=> [ User, Post ]
     ```
  
     @property relatedTypes
     @static
     @type Ember.Array
     @readOnly
     */
    relatedTypes: relatedTypesDescriptor,
  
    /**
     A map whose keys are the relationships of a model and whose values are
     relationship descriptors.
  
     For example, given a model with this
     definition:
  
     ```app/models/blog.js
     import DS from 'ember-data';
  
     export default DS.Model.extend({
        users: DS.hasMany('user'),
        owner: DS.belongsTo('user'),
  
        posts: DS.hasMany('post')
      });
     ```
  
     This property would contain the following:
  
     ```javascript
     import Ember from 'ember';
     import Blog from 'app/models/blog';
  
     let relationshipsByName = Ember.get(Blog, 'relationshipsByName');
     relationshipsByName.get('users');
     //=> { key: 'users', kind: 'hasMany', type: 'user', options: Object, isRelationship: true }
     relationshipsByName.get('owner');
     //=> { key: 'owner', kind: 'belongsTo', type: 'user', options: Object, isRelationship: true }
     ```
  
     @property relationshipsByName
     @static
     @type Ember.Map
     @readOnly
     */
    relationshipsByName: relationshipsByNameDescriptor,
  
    /**
     A map whose keys are the fields of the model and whose values are strings
     describing the kind of the field. A model's fields are the union of all of its
     attributes and relationships.
  
     For example:
  
     ```app/models/blog.js
     import DS from 'ember-data';
  
     export default DS.Model.extend({
        users: DS.hasMany('user'),
        owner: DS.belongsTo('user'),
  
        posts: DS.hasMany('post'),
  
        title: DS.attr('string')
      });
     ```
  
     ```js
     import Ember from 'ember';
     import Blog from 'app/models/blog';
  
     let fields = Ember.get(Blog, 'fields');
     fields.forEach(function(kind, field) {
        console.log(field, kind);
      });
  
     // prints:
     // users, hasMany
     // owner, belongsTo
     // posts, hasMany
     // title, attribute
     ```
  
     @property fields
     @static
     @type Ember.Map
     @readOnly
     */
    fields: computed(function() {
      let map = Map.create();
  
      this.eachComputedProperty((name, meta) => {
        if (meta.isRelationship) {
          map.set(name, meta.kind);
        } else if (meta.isAttribute) {
          map.set(name, 'attribute');
        }
      });
  
      return map;
    }).readOnly(),
  
    /**
     Given a callback, iterates over each of the relationships in the model,
     invoking the callback with the name of each relationship and its relationship
     descriptor.
  
     @method eachRelationship
     @static
     @param {Function} callback the callback to invoke
     @param {any} binding the value to which the callback's `this` should be bound
     */
    eachRelationship(callback, binding) {
      get(this, 'relationshipsByName').forEach((relationship, name) => {
        callback.call(binding, name, relationship);
      });
    },
  
    /**
     Given a callback, iterates over each of the types related to a model,
     invoking the callback with the related type's class. Each type will be
     returned just once, regardless of how many different relationships it has
     with a model.
  
     @method eachRelatedType
     @static
     @param {Function} callback the callback to invoke
     @param {any} binding the value to which the callback's `this` should be bound
     */
    eachRelatedType(callback, binding) {
      let relationshipTypes = get(this, 'relatedTypes');
  
      for (let i = 0; i < relationshipTypes.length; i++) {
        let type = relationshipTypes[i];
        callback.call(binding, type);
      }
    },
  
    determineRelationshipType(knownSide, store) {
      let knownKey = knownSide.key;
      let knownKind = knownSide.kind;
      let inverse = this.inverseFor(knownKey, store);
      // let key;
      let otherKind;
  
      if (!inverse) {
        return knownKind === 'belongsTo' ? 'oneToNone' : 'manyToNone';
      }
  
      // key = inverse.name;
      otherKind = inverse.kind;
  
      if (otherKind === 'belongsTo') {
        return knownKind === 'belongsTo' ? 'oneToOne' : 'manyToOne';
      } else {
        return knownKind === 'belongsTo' ? 'oneToMany' : 'manyToMany';
      }
    },
  
    /**
     A map whose keys are the attributes of the model (properties
     described by DS.attr) and whose values are the meta object for the
     property.
  
     Example
  
     ```app/models/person.js
     import DS from 'ember-data';
  
     export default DS.Model.extend({
        firstName: DS.attr('string'),
        lastName: DS.attr('string'),
        birthday: DS.attr('date')
      });
     ```
  
     ```javascript
     import Ember from 'ember';
     import Person from 'app/models/person';
  
     let attributes = Ember.get(Person, 'attributes')
  
     attributes.forEach(function(meta, name) {
        console.log(name, meta);
      });
  
     // prints:
     // firstName {type: "string", isAttribute: true, options: Object, parentType: function, name: "firstName"}
     // lastName {type: "string", isAttribute: true, options: Object, parentType: function, name: "lastName"}
     // birthday {type: "date", isAttribute: true, options: Object, parentType: function, name: "birthday"}
     ```
  
     @property attributes
     @static
     @type {Ember.Map}
     @readOnly
     */
    attributes: computed(function() {
      let map = Map.create();
  
      this.eachComputedProperty((name, meta) => {
        if (meta.isAttribute) {
          assert("You may not set `id` as an attribute on your model. Please remove any lines that look like: `id: DS.attr('<type>')` from " + this.toString(), name !== 'id');
  
          meta.name = name;
          map.set(name, meta);
        }
      });
  
      return map;
    }).readOnly(),
  
    /**
     A map whose keys are the attributes of the model (properties
     described by DS.attr) and whose values are type of transformation
     applied to each attribute. This map does not include any
     attributes that do not have an transformation type.
  
     Example
  
     ```app/models/person.js
     import DS from 'ember-data';
  
     export default DS.Model.extend({
        firstName: DS.attr(),
        lastName: DS.attr('string'),
        birthday: DS.attr('date')
      });
     ```
  
     ```javascript
     import Ember from 'ember';
     import Person from 'app/models/person';
  
     let transformedAttributes = Ember.get(Person, 'transformedAttributes')
  
     transformedAttributes.forEach(function(field, type) {
        console.log(field, type);
      });
  
     // prints:
     // lastName string
     // birthday date
     ```
  
     @property transformedAttributes
     @static
     @type {Ember.Map}
     @readOnly
     */
    transformedAttributes: computed(function() {
      let map = Map.create();
  
      this.eachAttribute((key, meta) => {
        if (meta.type) {
          map.set(key, meta.type);
        }
      });
  
      return map;
    }).readOnly(),
  
    /**
     Iterates through the attributes of the model, calling the passed function on each
     attribute.
  
     The callback method you provide should have the following signature (all
     parameters are optional):
  
     ```javascript
     function(name, meta);
     ```
  
     - `name` the name of the current property in the iteration
     - `meta` the meta object for the attribute property in the iteration
  
     Note that in addition to a callback, you can also pass an optional target
     object that will be set as `this` on the context.
  
     Example
  
     ```javascript
     import DS from 'ember-data';
  
     let Person = DS.Model.extend({
        firstName: DS.attr('string'),
        lastName: DS.attr('string'),
        birthday: DS.attr('date')
      });
  
     Person.eachAttribute(function(name, meta) {
        console.log(name, meta);
      });
  
     // prints:
     // firstName {type: "string", isAttribute: true, options: Object, parentType: function, name: "firstName"}
     // lastName {type: "string", isAttribute: true, options: Object, parentType: function, name: "lastName"}
     // birthday {type: "date", isAttribute: true, options: Object, parentType: function, name: "birthday"}
     ```
  
     @method eachAttribute
     @param {Function} callback The callback to execute
     @param {Object} [binding] the value to which the callback's `this` should be bound
     @static
     */
    eachAttribute(callback, binding) {
      get(this, 'attributes').forEach((meta, name) => {
        callback.call(binding, name, meta);
      });
    },
  
    /**
     Iterates through the transformedAttributes of the model, calling
     the passed function on each attribute. Note the callback will not be
     called for any attributes that do not have an transformation type.
  
     The callback method you provide should have the following signature (all
     parameters are optional):
  
     ```javascript
     function(name, type);
     ```
  
     - `name` the name of the current property in the iteration
     - `type` a string containing the name of the type of transformed
     applied to the attribute
  
     Note that in addition to a callback, you can also pass an optional target
     object that will be set as `this` on the context.
  
     Example
  
     ```javascript
     import DS from 'ember-data';
  
     let Person = DS.Model.extend({
        firstName: DS.attr(),
        lastName: DS.attr('string'),
        birthday: DS.attr('date')
      });
  
     Person.eachTransformedAttribute(function(name, type) {
        console.log(name, type);
      });
  
     // prints:
     // lastName string
     // birthday date
     ```
  
     @method eachTransformedAttribute
     @param {Function} callback The callback to execute
     @param {Object} [binding] the value to which the callback's `this` should be bound
     @static
     */
    eachTransformedAttribute(callback, binding) {
      get(this, 'transformedAttributes').forEach((type, name) => {
        callback.call(binding, name, type);
      });
    }
  });
  
  // if `Ember.setOwner` is defined, accessing `this.container` is
  // deprecated (but functional). In "standard" Ember usage, this
  // deprecation is actually created via an `.extend` of the factory
  // inside the container itself, but that only happens on models
  // with MODEL_FACTORY_INJECTIONS enabled :(
  if (setOwner) {
    Object.defineProperty(Model.prototype, 'container', {
      configurable: true,
      enumerable: false,
      get() {
        deprecate('Using the injected `container` is deprecated. Please use the `getOwner` helper instead to access the owner of this object.',
                        false,
                        { id: 'ember-application.injected-container', until: '3.0.0' });
  
        return this.store.container;
      }
    });
  }
  
  if (isEnabled('ds-rollback-attribute')) {
    Model.reopen({
      /**
        Discards any unsaved changes to the given attribute. This feature is not enabled by default. You must enable `ds-rollback-attribute` and be running a canary build.
  
        Example
  
        ```javascript
        record.get('name'); // 'Untitled Document'
        record.set('name', 'Doc 1');
        record.get('name'); // 'Doc 1'
        record.rollbackAttribute('name');
        record.get('name'); // 'Untitled Document'
        ```
  
        @method rollbackAttribute
      */
      rollbackAttribute(attributeName) {
        if (attributeName in this._internalModel._attributes) {
          this.set(attributeName, this._internalModel.lastAcknowledgedValue(attributeName));
        }
      }
    });
  }
  
  if (DEBUG) {
    Model.reopen({
      // This is a temporary solution until we refactor DS.Model to not
      // rely on the data property.
      willMergeMixin(props) {
        let constructor = this.constructor;
        assert('`' + intersection(Object.keys(props), RESERVED_MODEL_PROPS)[0] + '` is a reserved property name on DS.Model objects. Please choose a different property name for ' + constructor.toString(), !intersection(Object.keys(props), RESERVED_MODEL_PROPS)[0]);
        assert("You may not set `id` as an attribute on your model. Please remove any lines that look like: `id: DS.attr('<type>')` from " + constructor.toString(), Object.keys(props).indexOf('id') === -1);
      },
  
      /**
       This Ember.js hook allows an object to be notified when a property
       is defined.
  
       In this case, we use it to be notified when an Ember Data user defines a
       belongs-to relationship. In that case, we need to set up observers for
       each one, allowing us to track relationship changes and automatically
       reflect changes in the inverse has-many array.
  
       This hook passes the class being set up, as well as the key and value
       being defined. So, for example, when the user does this:
  
       ```javascript
       DS.Model.extend({
        parent: DS.belongsTo('user')
      });
       ```
  
       This hook would be called with "parent" as the key and the computed
       property returned by `DS.belongsTo` as the value.
  
       @method didDefineProperty
       @param {Object} proto
       @param {String} key
       @param {Ember.ComputedProperty} value
       */
      didDefineProperty(proto, key, value) {
        // Check if the value being set is a computed property.
        if (value instanceof ComputedProperty) {
  
          // If it is, get the metadata for the relationship. This is
          // populated by the `DS.belongsTo` helper when it is creating
          // the computed property.
          let meta = value.meta();
  
          meta.parentType = proto.constructor;
        }
      }
    });
  }
  
  export default Model;
  