#pragma once

#include <filesystem>


namespace vfs {

/**
 * Represent a virtual file system.
 * Real directory can be mounted to safely interact with the real file system.
 */
class VirtualFileSystem {

public:
    explicit VirtualFileSystem();
    ~VirtualFileSystem();

    [[nodiscard]] std::filesystem::path getWorkingDirectory() const;

    void setWorkingDirectory(const std::filesystem::path& virtualPath);

    /**
     * Mount a real directory into the virtual file system
     * @param sourcePath the path to the directory in the real file system
     * @param virtualDestinationPath the path to the directory in the virtual file system
     */
    void mount(const std::filesystem::path& sourcePath, const std::filesystem::path& virtualDestinationPath) const;

    /**
     * Unmount a directory from the virtual file system
     * @param virtualPath the path to the directory in the virtual file system
     */
    void unmount(const std::filesystem::path& virtualPath) const;

    /**
     * Get the real path on the host file system from its virtual path
     * @param virtualPath the virtual path
     * @return the real path
     */
    [[nodiscard]] std::filesystem::path resolve(const std::filesystem::path& virtualPath) const;

private:
    /// the internal temporary directory
    std::filesystem::path rootDirectoryPath;
    /// the virtual current working directory. Always relative.
    std::filesystem::path virtualWorkingDirectory;
};

}