1/*
2 * Copyright (c) 2021 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
16#ifndef FOUNDATION_ACE_FRAMEWORKS_BASE_UTILS_LINEAR_MAP_H
17#define FOUNDATION_ACE_FRAMEWORKS_BASE_UTILS_LINEAR_MAP_H
18
19#include <algorithm>
20#include <cstring>
21
22namespace OHOS::Ace {
23template<typename T>
24struct LinearMapNode {
25    const char* key;
26    T value;
27};
28
29// the key type K must can be compared.
30template<typename K, typename V>
31struct LinearEnumMapNode {
32    K key;
33    V value;
34};
35
36// these binary search functions in linear map, so the map must be sorted by key.
37template<typename T>
38int64_t BinarySearchFindIndex(const LinearMapNode<T>* vec, size_t length, const char* key)
39{
40    auto it = std::lower_bound(
41        vec, vec + length, key, [](LinearMapNode<T> lhs, const char* key) { return strcmp(lhs.key, key) < 0; });
42    if (it == vec + length || strcmp(it->key, key) != 0) {
43        return -1;
44    } else {
45        return it - vec;
46    }
47}
48
49template<typename K, typename V>
50int64_t BinarySearchFindIndex(const LinearEnumMapNode<K, V>* vec, size_t length, K key)
51{
52    auto it =
53        std::lower_bound(vec, vec + length, key, [](LinearEnumMapNode<K, V> lhs, K key) { return lhs.key < key; });
54    if (it == vec + length || it->key != key) {
55        return -1;
56    } else {
57        return it - vec;
58    }
59}
60} // namespace OHOS::Ace
61
62#endif // FOUNDATION_ACE_FRAMEWORKS_BASE_UTILS_LINEAR_MAP_H
63