Persisting query params

persist-qps.js

import { run } from '@ember/runloop';
import { action } from '@ember-decorators/object';
import storageFor from 'os-workflows/utils/storage-for-decorator';

const { assign } = Object;

export function withQueryParamMemory(Klass) {
  return class WithQueryParams extends Klass {
    @storageFor('route-memory')
    _memory;

    // NOTE: paramsFor is re-implemented to provide the model hooks with the appropriate
    // dynamic segments and query parameters (mimicking the default behavior)
    paramsFor(routeName) {
      const params = super.paramsFor(...arguments);
      const restoredQueryParams = this._findStoredQueryParams(
        routeName,
        this._router._routerMicrolib.activeTransition
      );

      const mergedParams = {
        ...params,
        ...restoredQueryParams
      };

      return mergedParams;
    }

    setupController(controller, model, transition) {
      super.setupController(...arguments);

      const restoredQueryParams = this._findStoredQueryParams(
        this.routeName,
        transition
      );

      run.schedule('afterRender', () => {
        controller.setProperties(restoredQueryParams);
        // Since we are deferring setting the query parameters (primarily so that they appear in the URL)
        // we much notify the controller once it's ready.  Logic that was previously done
        // inside of the setupController hook will need to be moved into some listener for this
        // event name.
        controller.trigger('readyState');
      });
    }

    _findStoredQueryParams(routeName /*, transition */) {
      // TODO: any qps in the transition object should cause the
      // restoration to bail out (return `null`)
      const manifest = this._memory.get('queryParams');

      if (routeName in manifest) {
        return manifest[routeName];
      }

      return null;
    }

    @action
    queryParamsDidChange(changed, preset, removed) {
      const { controller, routeName } = this;

      this._memory.set('queryParams', {
        ...this._memory.get('queryParams'),
        [this.routeName]: { ...preset }
      });

      this._recordQps(preset);
      this._scheduleParachuteChangeEvent(
        routeName,
        controller,
        assign({}, changed, removed)
      );

      return this._super(...arguments);
    }

    _recordQps(queryParams) {
      this._memory.set('queryParams', {
        ...this._memory.get('queryParams'),
        [this.routeName]: { ...queryParams }
      });
    }
  };
}