#pragma once

#if !defined(MIJIN_SOURCE_MIJIN_VIRTUAL_FILESYSTEM_MEMORY_HPP_INCLUDED)
#define MIJIN_SOURCE_MIJIN_VIRTUAL_FILESYSTEM_MEMORY_HPP_INCLUDED 1

#include <variant>
#include <vector>

#include "../container/vector_map.hpp"
#include "../util/flag.hpp"
#include "../virtual_filesystem/filesystem.hpp"

namespace mijin
{
namespace detail
{
struct MemoryFile
{
    std::span<const std::uint8_t> data;
};
struct MemoryFolder
{
    VectorMap<std::string, MemoryFile, std::allocator<std::string>, std::allocator<MemoryFile>> files; // TODO: make the FS library allocator aware
    VectorMap<std::string, MemoryFolder, std::allocator<std::string>, std::allocator<MemoryFolder>> folders;
};
}

class MemoryFileSystemAdapter : public FileSystemAdapter
{
public:
    MIJIN_DEFINE_FLAG(Overwrite);
    MIJIN_DEFINE_FLAG(CopyData);
private:
    detail::MemoryFolder root_;
    std::vector<std::vector<std::uint8_t>> fileData_;
public:
    [[nodiscard]] std::vector<FileInfo> listFiles(const fs::path& folder) override;
    [[nodiscard]] FileInfo getFileInfo(const fs::path& file) override;
    [[nodiscard]] StreamError open(const fs::path& path, FileOpenMode mode, std::unique_ptr<Stream>& outStream) override;

    bool addFile(const fs::path& path, std::span<const std::uint8_t> data, Overwrite overwrite = Overwrite::NO, CopyData copyData = CopyData::NO);
    bool addFile(const fs::path& path, std::span<const std::uint8_t> data, CopyData copyData)
    {
        return addFile(path, data, Overwrite::NO, copyData);
    }
    void addFolder(const fs::path& path);
private:
    detail::MemoryFolder* findFolder(const fs::path& path, bool create = false) MIJIN_NOEXCEPT;
    FileInfo folderInfo(const fs::path& path, const detail::MemoryFolder& folder) const MIJIN_NOEXCEPT;
    FileInfo fileInfo(const fs::path& path, const detail::MemoryFile& file) const MIJIN_NOEXCEPT;
};
} // namespace mijin

#endif // !defined(MIJIN_SOURCE_MIJIN_VIRTUAL_FILESYSTEM_MEMORY_HPP_INCLUDED)