import Ember from 'ember';

import _ from 'lodash';

import store from 'corpus-common-addon/utils/store';

export default Ember.Service.extend({

    promises: null,

    queryRegister: null,

    storeKeyBase: null,

    apiPath: null,

    resDocRoot: null,

    processId: function(id) { return id; },

    getReturnDictKey: function(id) { return id; },

    init() {

        this._super(...arguments);

        this.set('promises', []);

        this.set('queryRegister',{});

        this.doQuery = _.debounce(this._doQuery,10);

    },

    env: function() {

        return Ember.getOwner(this).resolveRegistration('config:environment');

    },

    _getStoreKey: function(id) {

        return this.storeKeyBase+':'+id;

    },

    _doQuery: function() {

        var queryRegister = this.get('queryRegister');

        this.set('queryRegister', {});

        var ids = Object.keys(queryRegister).join(',');

        if(!ids) {

            _.each(queryRegister, (resolve_reject) => {

                resolve_reject[0]({});

            });

        }

        Ember.$.ajax({

            //TODO Configuration ?

            success: (itemDoc) => {

                _.each(queryRegister, (resolve_reject) => {

                    resolve_reject[0](itemDoc[this.resDocRoot]);

                });

            },

            error: (req, status, error) => {

                _.each(queryRegister, (resolve_reject) => {

                    resolve_reject[1](status + ':' + error);

                });

            }

        });

    },

    // make the query for the name.

    // return a Promise

    queryName: function(id) {

        var queryRegister = this.get('queryRegister');

        return new Ember.RSVP.Promise(function(resolve, reject) {

            queryRegister[id] = [resolve, reject];

            this.doQuery(this);

        }.bind(this));

    },

    getName: function(id) {

        if(!id) {

            return new Ember.RSVP.Promise(function(resolve/*, reject*/) {

                resolve('');

            });

        }

        var objectId = this.processId(id);

        var namePromise = null;

        var storeKey = this._getStoreKey(id);

        var name = store.get(storeKey);

        if( name !== null) {

            namePromise = new Ember.RSVP.Promise(function(resolve/*, reject*/) {

                resolve(name);

            });

        } else if ( storeKey in this.get('promises')) {

            namePromise = this.get('promises')[storeKey];

        } else {

            //TODO: handle error !!!

            namePromise = this.queryName(objectId)

                .then(function(names) {

                    delete this.get('promises')[storeKey];

                    return store.set(storeKey, names[this.getReturnDictKey(objectId)]);

                }.bind(this));

            this.get('promises')[storeKey] = namePromise;

        }

        return namePromise;

    }

});