thingsboard/ui-ngx/src/app/shared/pipe/truncate.pipe.ts

///
/// Copyright © 2016-2022 The Thingsboard Authors
///
/// 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 { Pipe, PipeTransform } from '@angular/core';
import { isString } from '@core/utils';

@Pipe({ name: 'truncate' })
export class TruncatePipe implements PipeTransform {
  transform(text: string, wordwise: boolean, max: any, tail: string): string {
    if (!text) { return ''; }
    if (isString(max)) {
      max = parseInt(max, 10);
    }
    if (!max) { return text; }
    if (text.length <= max) { return text; }

    text = text.substr(0, max);
    if (wordwise) {
      let lastspace = text.lastIndexOf(' ');
      if (lastspace !== -1) {
        if (text.charAt(lastspace - 1) === '.' || text.charAt(lastspace - 1) === ',') {
          lastspace = lastspace - 1;
        }
        text = text.substr(0, lastspace);
      }
    }
    return text + (tail || ' …');
  }
}