// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef BASE_STRINGS_STRING_SPLIT_H_
#define BASE_STRINGS_STRING_SPLIT_H_

#include "fldserver/base/strings/string_piece.h"
#include "fldserver/fldserver_config.h"

#include <string>
#include <utility>
#include <vector>

namespace base
{
enum WhitespaceHandling
{
    KEEP_WHITESPACE,
    TRIM_WHITESPACE,
};

enum SplitResult
{
    // Strictly return all results.
    //
    // If the input is ",," and the separator is ',' this will return a
    // vector of three empty strings.
    SPLIT_WANT_ALL,

    // Only nonempty results will be added to the results. Multiple separators
    // will be coalesced. Separators at the beginning and end of the input will
    // be ignored. With TRIM_WHITESPACE, whitespace-only results will be dropped.
    //
    // If the input is ",," and the separator is ',', this will return an empty
    // vector.
    SPLIT_WANT_NONEMPTY,
};

// Split the given string on ANY of the given separators, returning copies of
// the result.
//
// Note this is inverse of JoinString() defined in string_util.h.
//
// To split on either commas or semicolons, keeping all whitespace:
//
//   std::vector<std::string> tokens = base::SplitString(
//       input, ",;", base::KEEP_WHITESPACE, base::SPLIT_WANT_ALL);
CORE_EXPORT std::vector<std::string>
SplitString(StringPiece input,
            StringPiece separators,
            WhitespaceHandling whitespace,
            SplitResult result_type) WARN_UNUSED_RESULT;
CORE_EXPORT std::vector<std::u16string>
SplitString(StringPiece16 input,
            StringPiece16 separators,
            WhitespaceHandling whitespace,
            SplitResult result_type) WARN_UNUSED_RESULT;

// Like SplitString above except it returns a vector of StringPieces which
// reference the original buffer without copying. Although you have to be
// careful to keep the original string unmodified, this provides an efficient
// way to iterate through tokens in a string.
//
// Note this is inverse of JoinString() defined in string_util.h.
//
// To iterate through all whitespace-separated tokens in an input string:
//
//   for (const auto& cur :
//        base::SplitStringPiece(input, base::kWhitespaceASCII,
//                               base::KEEP_WHITESPACE,
//                               base::SPLIT_WANT_NONEMPTY)) {
//     ...
CORE_EXPORT std::vector<StringPiece>
SplitStringPiece(StringPiece input,
                 StringPiece separators,
                 WhitespaceHandling whitespace,
                 SplitResult result_type) WARN_UNUSED_RESULT;
CORE_EXPORT std::vector<StringPiece16>
SplitStringPiece(StringPiece16 input,
                 StringPiece16 separators,
                 WhitespaceHandling whitespace,
                 SplitResult result_type) WARN_UNUSED_RESULT;

using StringPairs = std::vector<std::pair<std::string, std::string>>;

// Splits |line| into key value pairs according to the given delimiters and
// removes whitespace leading each key and trailing each value. Returns true
// only if each pair has a non-empty key and value. |key_value_pairs| will
// include ("","") pairs for entries without |key_value_delimiter|.
CORE_EXPORT bool
SplitStringIntoKeyValuePairs(StringPiece input,
                             char key_value_delimiter,
                             char key_value_pair_delimiter,
                             StringPairs* key_value_pairs);

// Similar to SplitStringIntoKeyValuePairs, but use a substring
// |key_value_pair_delimiter| instead of a single char.
CORE_EXPORT bool
SplitStringIntoKeyValuePairsUsingSubstr(StringPiece input,
                                        char key_value_delimiter,
                                        StringPiece key_value_pair_delimiter,
                                        StringPairs* key_value_pairs);

// Similar to SplitString, but use a substring delimiter instead of a list of
// characters that are all possible delimiters.
CORE_EXPORT std::vector<std::u16string>
SplitStringUsingSubstr(StringPiece16 input,
                       StringPiece16 delimiter,
                       WhitespaceHandling whitespace,
                       SplitResult result_type) WARN_UNUSED_RESULT;
CORE_EXPORT std::vector<std::string>
SplitStringUsingSubstr(StringPiece input,
                       StringPiece delimiter,
                       WhitespaceHandling whitespace,
                       SplitResult result_type) WARN_UNUSED_RESULT;

// Like SplitStringUsingSubstr above except it returns a vector of StringPieces
// which reference the original buffer without copying. Although you have to be
// careful to keep the original string unmodified, this provides an efficient
// way to iterate through tokens in a string.
//
// To iterate through all newline-separated tokens in an input string:
//
//   for (const auto& cur :
//        base::SplitStringUsingSubstr(input, "\r\n",
//                                     base::KEEP_WHITESPACE,
//                                     base::SPLIT_WANT_NONEMPTY)) {
//     ...
CORE_EXPORT std::vector<StringPiece16>
SplitStringPieceUsingSubstr(StringPiece16 input,
                            StringPiece16 delimiter,
                            WhitespaceHandling whitespace,
                            SplitResult result_type) WARN_UNUSED_RESULT;
CORE_EXPORT std::vector<StringPiece>
SplitStringPieceUsingSubstr(StringPiece input,
                            StringPiece delimiter,
                            WhitespaceHandling whitespace,
                            SplitResult result_type) WARN_UNUSED_RESULT;

}  // namespace base

#if IS_WIN
#include "fldserver/base/strings/string_split_win.h"
#endif

#endif  // BASE_STRINGS_STRING_SPLIT_H_
