// Copyright 2015 The Shaderc Authors. All rights reserved.

//

// 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.

#ifndef GLSLC_FILE_INCLUDER_H_

#define GLSLC_FILE_INCLUDER_H_

#include <mutex>

#include <string>

#include <unordered_map>

#include <unordered_set>

#include <utility>

#include <vector>

#include <unordered_set>

#include "libshaderc_util/file_finder.h"

#include "shaderc/shaderc.hpp"

namespace glslc {

// An includer for files implementing shaderc's includer interface. It responds

// to the file including query from the compiler with the full path and content

// of the file to be included. In the case that the file is not found or cannot

// be opened, the full path field of in the response will point to an empty

// string, and error message will be passed to the content field.

// This class provides the basic thread-safety guarantee.

class FileIncluder : public shaderc::CompileOptions::IncluderInterface {

 public:

  explicit FileIncluder(const shaderc_util::FileFinder* file_finder)

      : file_finder_(*file_finder) {}

  ~FileIncluder() override;

  // Resolves a requested source file of a given type from a requesting

  // source into a shaderc_include_result whose contents will remain valid

  // until it's released.

  shaderc_include_result* GetInclude(const char* requested_source,

                                     shaderc_include_type type,

                                     const char* requesting_source,

                                     size_t include_depth) override;

  // Releases an include result.

  void ReleaseInclude(shaderc_include_result* include_result) override;

  // Returns a reference to the member storing the set of included files.

  const std::unordered_set<std::string>& file_path_trace() const {

    return included_files_;

  }

 private:

  // Used by GetInclude() to get the full filepath.

  const shaderc_util::FileFinder& file_finder_;

  // The full path and content of a source file.

  struct FileInfo {

    const std::string full_path;

    std::vector<char> contents;

  };

  // The set of full paths of included files.

  std::unordered_set<std::string> included_files_;

};

}  // namespace glslc

#endif  // GLSLC_FILE_INCLUDER_H_