// Copyright 2023 The Abseil 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

//

//     https://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.

#include "absl/log/internal/fnmatch.h"

#include <cstddef>

#include "absl/base/config.h"

#include "absl/strings/string_view.h"

namespace absl {

ABSL_NAMESPACE_BEGIN

namespace log_internal {

bool FNMatch(absl::string_view pattern, absl::string_view str) {

  bool in_wildcard_match = false;

  while (true) {

    if (pattern.empty()) {

      // `pattern` is exhausted; succeed if all of `str` was consumed matching

      // it.

      return in_wildcard_match || str.empty();

    }

    if (str.empty()) {

      // `str` is exhausted; succeed if `pattern` is empty or all '*'s.

      return pattern.find_first_not_of('*') == pattern.npos;

    }

    switch (pattern.front()) {

      case '*':

        pattern.remove_prefix(1);

        in_wildcard_match = true;

        break;

      case '?':

        pattern.remove_prefix(1);

        str.remove_prefix(1);

        break;

      default:

        if (in_wildcard_match) {

          absl::string_view fixed_portion = pattern;

          const size_t end = fixed_portion.find_first_of("*?");

          if (end != fixed_portion.npos) {

            fixed_portion = fixed_portion.substr(0, end);

          }

          const size_t match = str.find(fixed_portion);

          if (match == str.npos) {

            return false;

          }

          pattern.remove_prefix(fixed_portion.size());

          str.remove_prefix(match + fixed_portion.size());

          in_wildcard_match = false;

        } else {

          if (pattern.front() != str.front()) {

            return false;

          }

          pattern.remove_prefix(1);

          str.remove_prefix(1);

        }

        break;

    }

  }

}

}  // namespace log_internal

ABSL_NAMESPACE_END

}  // namespace absl