• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1/*
2 * Copyright (c) 2023 Huawei Device Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 *     http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16import type {INameGenerator, NameGeneratorOptions} from './INameGenerator';
17
18/**
19 * @Desc: a name generator which use given identifiers to get incremental obfuscated name
20 */
21export class DictionaryNameGenerator implements INameGenerator {
22  private readonly mDictionaryList: string[];
23  private readonly mReservedNames: Set<string>;
24
25  private mDictIndex: number;
26  private mTransformNumber: number;
27
28  /**
29   *
30   * @param options: {dictionaryList: list}
31   */
32  constructor(options?: NameGeneratorOptions) {
33    this.mDictionaryList = (options && options.dictionaryList) ? options.dictionaryList : ['hello', 'world', 'dictionary', 'light', 'thunder', 'storm'];
34    this.mReservedNames = options?.reservedNames;
35
36    this.mDictIndex = 0;
37    this.mTransformNumber = 0;
38  }
39
40  /**
41   * @return: null for end
42   */
43  public getName(): string {
44    if (this.mDictIndex >= this.mDictionaryList.length) {
45      return null;
46    }
47
48    let originIdentifier: string[] = Array.from(this.mDictionaryList[this.mDictIndex].toLowerCase());
49    const BINARY_RADIX: number = 2;
50    let binary: string = this.mTransformNumber.toString(BINARY_RADIX).split('').reverse().join('');
51    let countTrue: number = 0;
52    for (let i = 0; i < binary.length; i++) {
53      if (binary[i] === '1') {
54        originIdentifier[i] = originIdentifier[i].toUpperCase();
55        countTrue += 1;
56      }
57    }
58
59    this.mTransformNumber += 1;
60    if (countTrue >= originIdentifier.length) {
61      this.mDictIndex += 1;
62      this.mTransformNumber = 0;
63    }
64
65    if (this.mReservedNames?.has(originIdentifier.join(''))) {
66      return this.getName();
67    }
68
69    return originIdentifier.join('');
70  }
71
72  public reset(): void {
73    this.mDictIndex = 0;
74    this.mTransformNumber = 0;
75  }
76}
77