/*
 * Copyright (c) 2017-2024 OARC, Inc.
 * Copyright (c) 2011-2017, IIS - The Internet Foundation in Sweden
 * All rights reserved.
 *
 * This file is part of PacketQ.
 *
 * PacketQ is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * PacketQ is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with PacketQ.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "reader.h"
#include "packet_handler.h"

namespace packetq {

void Reader::seek_to_start()
{
    currently_reading = filenames.begin();
    pcap.reset();
    packets_read = 0;
}

bool Reader::done()
{
    return (!pcap && currently_reading == filenames.end()) || (max_packets > 0 && packets_read >= max_packets);
}

bool Reader::read_next(Packet_handler* handler, const std::vector<int>& columns, Row& destination_row, int skip_packets)
{
    bool filled_in_row = false;

    while (!filled_in_row and !done()) {
        // try opening pcap file
        if (!pcap && currently_reading != filenames.end()) {
            FILE* fp = fopen(currently_reading->c_str(), "rb");
            if (fp) {
                pcap.reset(new Pcap_file(fp, Pcap_file::TAKE_OVER_FP));

                if (!pcap->get_header())
                    pcap.reset();
            }

            if (!pcap)
                ++currently_reading;
        }

        // try reading a row
        if (pcap) {
            int            len, s, us;
            unsigned char* data         = pcap->get_packet(len, s, us);
            bool           read_success = len && data;
            ++packets_read; // we count all packets
            if (read_success) {
                Packet              packet(data, len, s, us, packets_read, pcap->get_link_layer_type());
                Packet::ParseResult res = packet.parse(handler, columns, destination_row, skip_packets == 0);

                if (res == Packet::NOT_SAMPLED)
                    --skip_packets;

                filled_in_row = res == Packet::OK;
            } else {
                // last row in file
                pcap.reset();
                if (currently_reading != filenames.end())
                    ++currently_reading;
            }
        }
    }

    return filled_in_row;
}

} // namespace packetq