1 /*
2  * Copyright (c) 2024 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 META_SRC_LOADERS_CSV_PARSER_H
17 #define META_SRC_LOADERS_CSV_PARSER_H
18 
19 #include <base/containers/string.h>
20 #include <base/containers/string_view.h>
21 #include <base/containers/vector.h>
22 
23 #include <meta/base/namespace.h>
24 
25 META_BEGIN_NAMESPACE()
26 
27 /**
28  * @brief The CsvParser class implements a simple CSV parser, which
29  *        parses a given CSV format string.
30  *        The parser supports non-quoted and quoted items, separated
31  *        by a configurable delimiter. Also multiline quotes are
32  *        supported.
33  */
34 class CsvParser {
35 public:
36     CsvParser() = delete;
37     explicit CsvParser(BASE_NS::string_view csv, const char delimiter = ',');
38 
39     using CsvRow = BASE_NS::vector<BASE_NS::string>;
40 
41     /**
42      * @brief GetRow returns the next row from the CSV file.
43      *        Regularly the user should call GetRow in a loop until
44      *        the function returns false (either parse error or
45      *        end of the CSV file).
46      * @param row Row items will be placed here.
47      * @return True if parsing was successful, false otherwide.
48      */
49     bool GetRow(CsvRow& row);
50     /**
51      * @brief Resets to the beginning of the CSV string.
52      */
53     void Reset();
54 
55 private:
56     enum State {
57         NO_QUOTE,
58         IN_QUOTE,
59         QUOTED,
60     };
61     CsvRow ParseRow();
62     BASE_NS::string_view Trimmed(BASE_NS::string_view sv, State state);
63 
64     char delimiter_ {};
65     BASE_NS::string csv_;
66     size_t pos_ {};
67 };
68 
69 META_END_NAMESPACE()
70 
71 #endif
72