#pragma once

#include <boost/asio/buffer.hpp>

#include <cstddef>
#include <functional>
#include <vector>

namespace xrpl {

class Writer
{
public:
    virtual ~Writer() = default;

    /**
     * Returns `true` if there is no more data to pull.
     */
    virtual bool
    complete() = 0;

    /**
     * Removes bytes from the input sequence.
     *
     * Can be called with 0.
     */
    virtual void
    consume(std::size_t bytes) = 0;

    /**
     * Add data to the input sequence.
     * @param bytes A hint to the number of bytes desired.
     * @param resume A functor to later resume execution.
     * @return `true` if the writer is ready to provide more data.
     */
    virtual bool
    prepare(std::size_t bytes, std::function<void(void)> resume) = 0;

    /**
     * Returns a ConstBufferSequence representing the input sequence.
     */
    virtual std::vector<boost::asio::const_buffer>
    data() = 0;
};

}  // namespace xrpl