util.hh

#ifndef __VEREIGN_FS_UTIL_HH
#define __VEREIGN_FS_UTIL_HH

#include <vereign/bytes/buffer.hh>
#include <boost/filesystem/path.hpp>
#include <string>
#include <string_view>

namespace vereign::fs {

namespace detail {

auto PathToString(const boost::filesystem::path& path) -> std::string;
auto StringToPath(std::string_view path) -> boost::filesystem::path;

} // namespace detail

/**
 * A RAII guard that deletes a file upon destruction.
 */
class RemoveFileGuard {
public:
  RemoveFileGuard(std::string path);
  ~RemoveFileGuard();

  RemoveFileGuard(const RemoveFileGuard&) = delete;
  auto operator=(const RemoveFileGuard&) -> RemoveFileGuard& = delete;
private:
  std::string path_;
};

/**
 * A RAII guard that deletes all files and directories recursively.
 */
class RemoveAllGuard {
public:
  RemoveAllGuard(std::string path);
  ~RemoveAllGuard();

  RemoveAllGuard(const RemoveAllGuard&) = delete;
  auto operator=(const RemoveAllGuard&) -> RemoveAllGuard& = delete;
private:
  std::string path_;
};

/**
 * Generates a file path usable as temporary file.
 *
 * For a temp file path under the system tmp dir use the other TempFilePath overload.
 *
 * @code
 * auto path = fs::TempFilePath("/tmp/foo", "test_db_");
 * std::cout << path << std::endl;
 *
 * // Output:
 * // /tmp/foo/test_db_bh0vcr0jbz
 * @endcode
 *
 * @param dir The directory of the temp file path.
 * @param prefix A prefix to prepend to the temp file name.
 * @returns a file path usable as temporary file.
 */
auto TempFilePath(std::string_view dir, std::string_view prefix) -> std::string;

/**
 * Generates a file path usable as temporary file under the system temporary directory.
 *
 * It tries to detect the correct temp dir under different operation systems.
 * For Linux this is `/tmp` and for Windows this is `C:\Users\<username>\AppData\Local\Temp`.
 *
 * @code
 * auto path = fs::TempFilePath("test_db_");
 * std::cout << path << std::endl;
 *
 * // Output:
 * // /tmp/test_db_bh0vcr0jbz
 * @endcode
 *
 * @param prefix A prefix to prepend to the temp file name.
 * @returns a file path usable as temporary file.
 */
auto TempFilePath(std::string_view prefix) -> std::string;

/**
 * Creates a temporary sub directory under the system temporary directory.
 *
 * It tries to detect the correct temp dir under different operation systems.
 * For Linux this is `/tmp` and for Windows this is `C:\Users\<username>\AppData\Local\Temp`.
 *
 * @code
 * auto path = fs::TempDir("test_db_");
 * std::cout << path << std::endl;
 *
 * // Output:
 * // /tmp/test_db_bh0vcr0jbz
 * @endcode
 *
 * @param prefix A prefix to prepend to the temp dir name.
 * @returns a the path of the created temporary directory.
 */
auto TempDir(std::string_view prefix) -> std::string;

/**
 * Returns current user home directory.
 *
 * On Windows this is `C:\Users\<username>\AppData\Local`.
 *
 * @returns the user's home directory full path.
 */
auto HomePath() -> std::string;

auto ReadFile(std::string_view path) -> bytes::Buffer;
void WriteFile(std::string_view path, bytes::View data);

} // namespace vereign::fs

#endif // __VEREIGN_FS_UTIL_HH