#pragma once
///@file

#include "nix/store/store-api.hh"
#include "nix/store/gc-store.hh"
#include "nix/store/log-store.hh"

namespace nix {

struct LocalFSStoreConfig : virtual StoreConfig
{
private:
    static OptionalPathSetting makeRootDirSetting(LocalFSStoreConfig & self, std::optional<Path> defaultValue)
    {
        return {
            &self,
            std::move(defaultValue),
            "root",
            "Directory prefixed to all other paths.",
        };
    }

public:
    using StoreConfig::StoreConfig;

    /**
     * Used to override the `root` settings. Can't be done via modifying
     * `params` reliably because this parameter is unused except for
     * passing to base class constructors.
     *
     * @todo Make this less error-prone with new store settings system.
     */
    LocalFSStoreConfig(PathView path, const Params & params);

    OptionalPathSetting rootDir = makeRootDirSetting(*this, std::nullopt);

private:

    /**
     * An indirection so that we don't need to refer to global settings
     * in headers.
     */
    static Path getDefaultStateDir();

    /**
     * An indirection so that we don't need to refer to global settings
     * in headers.
     */
    static Path getDefaultLogDir();

public:

    PathSetting stateDir{
        this,
        rootDir.get() ? *rootDir.get() + "/nix/var/nix" : getDefaultStateDir(),
        "state",
        "Directory where Nix stores state."};

    PathSetting logDir{
        this,
        rootDir.get() ? *rootDir.get() + "/nix/var/log/nix" : getDefaultLogDir(),
        "log",
        "directory where Nix stores log files."};

    PathSetting realStoreDir{
        this, rootDir.get() ? *rootDir.get() + "/nix/store" : storeDir, "real", "Physical path of the Nix store."};
};

struct LocalFSStore : virtual Store, virtual GcStore, virtual LogStore
{
    using Config = LocalFSStoreConfig;

    const Config & config;

    inline static std::string operationName = "Local Filesystem Store";

    const static std::string drvsLogDir;

    LocalFSStore(const Config & params);

    void narFromPath(const StorePath & path, Sink & sink) override;
    ref<SourceAccessor> getFSAccessor(bool requireValidPath = true) override;
    std::shared_ptr<SourceAccessor> getFSAccessor(const StorePath & path, bool requireValidPath = true) override;

    /**
     * Creates symlink from the `gcRoot` to the `storePath` and
     * registers the `gcRoot` as a permanent GC root. The `gcRoot`
     * symlink lives outside the store and is created and owned by the
     * user.
     *
     * @param gcRoot The location of the symlink.
     *
     * @param storePath The store object being rooted. The symlink will
     * point to `toRealPath(store.printStorePath(storePath))`.
     *
     * How the permanent GC root corresponding to this symlink is
     * managed is implementation-specific.
     */
    virtual Path addPermRoot(const StorePath & storePath, const Path & gcRoot) = 0;

    virtual Path getRealStoreDir()
    {
        return config.realStoreDir;
    }

    Path toRealPath(const Path & storePath) override
    {
        assert(isInStore(storePath));
        return getRealStoreDir() + "/" + std::string(storePath, storeDir.size() + 1);
    }

    std::optional<std::string> getBuildLogExact(const StorePath & path) override;
};

} // namespace nix
