/*

Copyright (c) 2007, 2009, 2011-2016, 2019-2020, Arvid Norberg
Copyright (c) 2016, 2018, 2020, Alden Torres
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:

    * Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.
    * Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in
      the documentation and/or other materials provided with the distribution.
    * Neither the name of the author nor the names of its
      contributors may be used to endorse or promote products derived
      from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.

*/

#ifndef TORRENT_BANDWIDTH_MANAGER_HPP_INCLUDED
#define TORRENT_BANDWIDTH_MANAGER_HPP_INCLUDED

#include <memory>
#include <vector>

#include "libtorrent/aux_/invariant_check.hpp"
#include "libtorrent/assert.hpp"
#include "libtorrent/aux_/bandwidth_limit.hpp"
#include "libtorrent/aux_/bandwidth_queue_entry.hpp"
#include "libtorrent/aux_/bandwidth_socket.hpp"
#include "libtorrent/time.hpp"

namespace libtorrent {
namespace aux {

struct TORRENT_EXTRA_EXPORT bandwidth_manager
{
	explicit bandwidth_manager(int channel);

	void close();

#if TORRENT_USE_ASSERTS
	bool is_queued(bandwidth_socket const* peer) const;
#endif

	int queue_size() const;
	std::int64_t queued_bytes() const;

	// non prioritized means that, if there's a line for bandwidth,
	// others will cut in front of the non-prioritized peers.
	// this is used by web seeds
	// returns the number of bytes to assign to the peer, or 0
	// if the peer's 'assign_bandwidth' callback will be called later
	int request_bandwidth(std::shared_ptr<bandwidth_socket> peer
		, int blk, int priority, bandwidth_channel** chan, int num_channels);

#if TORRENT_USE_INVARIANT_CHECKS
	void check_invariant() const;
#endif

	void update_quotas(time_duration const& dt);

private:

	// these are the consumers that want bandwidth
	std::vector<bw_request> m_queue;
	// the number of bytes all the requests in queue are for
	std::int64_t m_queued_bytes;

	// this is the channel within the consumers
	// that bandwidth is assigned to (upload or download)
	int m_channel;

	bool m_abort;
};

}
}

#endif
