/**
 * @license
 * Copyright (C) 2017 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import {encodeURL, getBaseUrl} from '../../utils/url-util';
import {PolymerElement} from '@polymer/polymer';
import {Constructor} from '../../utils/common-util';

/**
 * @polymer
 * @mixinFunction
 */
export const ListViewMixin = <T extends Constructor<PolymerElement>>(
  superClass: T
) => {
  /**
   * @polymer
   * @mixinClass
   */
  class Mixin extends superClass {
    computeLoadingClass(loading: boolean): string {
      return loading ? 'loading' : '';
    }

    computeShownItems<T>(items: T[]): T[] {
      return items.slice(0, 25);
    }

    getUrl(path: string, item: string) {
      return getBaseUrl() + path + encodeURL(item, true);
    }

    getFilterValue<T extends ListViewParams>(params: T): string {
      if (!params) {
        return '';
      }
      return params.filter || '';
    }

    getOffsetValue<T extends ListViewParams>(params: T): number {
      if (params?.offset) {
        return Number(params.offset);
      }
      return 0;
    }
  }

  return Mixin as T & Constructor<ListViewMixinInterface>;
};

export interface ListViewMixinInterface {
  computeLoadingClass(loading: boolean): string;
  computeShownItems<T>(items: T[]): T[];
  getUrl(path: string, item: string): string;
  getFilterValue<T extends ListViewParams>(params: T): string;
  getOffsetValue<T extends ListViewParams>(params: T): number;
}

export interface ListViewParams {
  filter?: string | null;
  offset?: number | string;
}