/*

Copyright (c) 2015-2021, Arvid Norberg
Copyright (c) 2019, 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_FILE_PROGRESS_HPP_INCLUDE
#define TORRENT_FILE_PROGRESS_HPP_INCLUDE

#include <vector>
#include <cstdint>
#include <functional>

#include "libtorrent/aux_/export.hpp"
#include "libtorrent/units.hpp"
#include "libtorrent/aux_/vector.hpp"

#if TORRENT_USE_INVARIANT_CHECKS
#include "libtorrent/bitfield.hpp"
#include "libtorrent/aux_/invariant_check.hpp"
#endif

#if TORRENT_USE_INVARIANT_CHECKS
#include "libtorrent/aux_/invariant_check.hpp"
#include "libtorrent/bitfield.hpp"
#endif

namespace libtorrent {

struct piece_picker;
class file_storage;

namespace aux {

	struct TORRENT_EXTRA_EXPORT file_progress
	{
		file_progress() = default;

		void init(piece_picker const& picker
			, file_storage const& fs);

		void export_progress(vector<std::int64_t, file_index_t> &fp);

		std::int64_t total_on_disk() const
		{
			return m_total_on_disk;
		}

		bool empty() const { return m_file_progress.empty(); }
		void clear();

		void update(file_storage const& fs, piece_index_t index
			, std::function<void(file_index_t)> const& completed_cb);

#if TORRENT_USE_INVARIANT_CHECKS
		bool have_piece(piece_index_t index) const
		{
			if (m_have_pieces.empty()) return false;
			return m_have_pieces.get_bit(index);
		}
#endif

	private:

		// the total number of bytes downloaded to non-pad files
		std::int64_t m_total_on_disk = 0;

		// this vector contains the number of bytes completely
		// downloaded (as in passed-hash-check) in each file.
		// this lets us trigger on individual files completing
		// the vector is allocated lazily, when file progress
		// is first queried by the client
		vector<std::int64_t, file_index_t> m_file_progress;

#if TORRENT_USE_INVARIANT_CHECKS
		friend struct libtorrent::invariant_access;
		void check_invariant() const;

		// this is used to assert we never add the same piece twice
		typed_bitfield<piece_index_t> m_have_pieces;

		// to make sure we never say we've downloaded more bytes of a file than
		// its file size
		vector<std::int64_t, file_index_t> m_file_sizes;
		vector<bool, file_index_t> m_pad_file;
#endif
	};
} }

#endif
