#pragma once

#include <xrpl/basics/Blob.h>
#include <xrpl/basics/CountedObject.h>
#include <xrpl/basics/base_uint.h>

// VFALCO NOTE Intentionally not in the NodeStore namespace

namespace xrpl {

/** The types of node objects. */
enum NodeObjectType : std::uint32_t {
    hotUNKNOWN = 0,
    hotLEDGER = 1,
    hotACCOUNT_NODE = 3,
    hotTRANSACTION_NODE = 4,
    hotDUMMY = 512  // an invalid or missing object
};

/** A simple object that the Ledger uses to store entries.
    NodeObjects are comprised of a type, a hash, and a blob.
    They can be uniquely identified by the hash, which is a half-SHA512 of
    the blob. The blob is a variable length block of serialized data. The
    type identifies what the blob contains.

    @note No checking is performed to make sure the hash matches the data.
    @see SHAMap
*/
class NodeObject : public CountedObject<NodeObject>
{
public:
    static constexpr std::size_t keyBytes = 32;

private:
    // This hack is used to make the constructor effectively private
    // except for when we use it in the call to make_shared.
    // There's no portable way to make make_shared<> a friend work.
    struct PrivateAccess
    {
        explicit PrivateAccess() = default;
    };

public:
    // This constructor is private, use createObject instead.
    NodeObject(NodeObjectType type, Blob&& data, uint256 const& hash, PrivateAccess);

    /** Create an object from fields.

        The caller's variable is modified during this call. The
        underlying storage for the Blob is taken over by the NodeObject.

        @param type The type of object.
        @param ledgerIndex The ledger in which this object appears.
        @param data A buffer containing the payload. The caller's variable
                    is overwritten.
        @param hash The 256-bit hash of the payload data.
    */
    static std::shared_ptr<NodeObject>
    createObject(NodeObjectType type, Blob&& data, uint256 const& hash);

    /** Returns the type of this object. */
    NodeObjectType
    getType() const;

    /** Returns the hash of the data. */
    uint256 const&
    getHash() const;

    /** Returns the underlying data. */
    Blob const&
    getData() const;

private:
    NodeObjectType const mType;
    uint256 const mHash;
    Blob const mData;
};

}  // namespace xrpl
