import Ember from 'ember';

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

import * as constants from 'corpus-common-addon/utils/constants'

export default Ember.Service.extend({

  env: function() {

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

  },

  _getStoreKey: function(id) {

    return 'bnf:'+id;

  },

  getLabel: function(id) {

    if(!id) {

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

        resolve("");

      });

    }

    var bnfId = id;

    if(id.startsWith(constants.BNF_BASE_URL + constants.BNF_ARK_BASE_ID)) {

      bnfId = id.slice((constants.BNF_BASE_URL + constants.BNF_ARK_BASE_ID).length);

    }

    else if (id.startsWith(constants.BNF_ARK_BASE_URL + constants.BNF_ARK_BASE_ID)) {

      bnfId = id.slice((constants.BNF_ARK_BASE_URL + constants.BNF_ARK_BASE_ID).length);

    }

    else if (id.startsWith(constants.BNF_ARK_BASE_ID)) {

      bnfId = id.slice(constants.BNF_ARK_BASE_ID.length);

    }

    var labelPromise = null;

    var storeKey = this._getStoreKey(id);

    var label = store.get(storeKey);

    if(!label) {

      //TODO: handle error !!!

      labelPromise = this.queryLabel(bnfId)

        .then( function(response) {

            return store.set(storeKey, response);

        });

    }

    else {

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

        resolve(label);

      });

    }

    return labelPromise;

  },

  // make the query for the name.

  // return a Promise

  queryLabel: function(id) {

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

      Ember.$.ajax({

        //TODO Configuration for the host ?

        url: this.env().baseURL.replace(/\/$/,"") + "/api/v1/bnf/"+id,

        success: function(bnfDoc) {

          var labels = bnfDoc.bnfids;

          var expectedId = constants.BNF_ARK_BASE_ID + id;

          resolve((expectedId in labels)?labels[expectedId]:null);

        },

        error: function(req, status, error) {

          reject(status + ":" + error);

        }

      });

    }.bind(this));

  }

});