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));
  }


});