// Copyright 2018 Google LLC

//

// 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

//

// http://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 "cc/file/path.h"

#include "absl/strings/str_cat.h"

namespace minigo {

namespace file {

namespace internal {

std::string JoinPathImpl(std::initializer_list<absl::string_view> paths) {

std::string result;

for (auto path : paths) {

if (path.empty()) {

continue;

}

if (result.empty()) {

result.assign(path.data(), path.size());

continue;

}

if (result.back() == '/') {

if (path[0] == '/') {

absl::StrAppend(&result, path.substr(1));

} else {

absl::StrAppend(&result, path);

}

} else {

if (path[0] == '/') {

absl::StrAppend(&result, path);

} else {

absl::StrAppend(&result, "/", path);

}

}

}

return result;

}

} // namespace internal

std::pair<absl::string_view, absl::string_view> SplitPath(

absl::string_view path) {

auto pos = path.find_last_of('/');

// No '/' in path.

if (pos == absl::string_view::npos) {

return std::make_pair(path.substr(0, 0), path);

}

// Leading '/'.

if (pos == 0) {

return std::make_pair(path.substr(0, 1), absl::ClippedSubstr(path, 1));

}

// General case.

return std::make_pair(path.substr(0, pos),

absl::ClippedSubstr(path, pos + 1));

}

} // namespace file

} // namespace minigo