/*
 * Copyright 2016
 * 
 * ReceiverThreads.cpp
 *
 *  Created on: 21.07.2016
 *      Author: Tobias Frust
 */

#include <iostream>

#include "ReceiverThreads.h"
#include "../UDPServer/UDPServer.h"

#include <sys/epoll.h>
#include <vma_extra.h>

//#define USE_VMA

ReceiverThreads::ReceiverThreads(const std::string& address, const int timeIntervall, const int numberOfDetectorModules, const int firstPort)
   : timeIntervall_{timeIntervall}, firstPort_{firstPort}, numberOfDetectorModules_{numberOfDetectorModules}, address_{address}, loss_{0}, nbufs_(100) {

   int max_packet_size = 65535;

#ifdef USE_VMA
   vma_ = vma_get_api();
	// First call fails?
   if (!vma_) vma_ = vma_get_api();
#else 
   vma_ =  NULL;
#endif

   ringbuf_.resize(nbufs_);
    for (int i = 0; i < nbufs_; i++)
	ringbuf_[i].resize(numberOfDetectorModules * max_packet_size);

   for(auto i = 0; i < numberOfDetectorModules; i++){
      receiverModules_.emplace_back(&ReceiverThreads::receiverThread, this, firstPort+i);
   }

   for(auto i = 0; i < numberOfDetectorModules; i++){
      receiverModules_[i].join();
   }
}

auto ReceiverThreads::receiverThread(const int port) -> void {
    int vma_ring_fd;

    int max_packets = 100;
    int max_packet_size = 65535;
    int id = port - firstPort_;

    UDPServer server = UDPServer(address_, port);
    std::vector<std::vector<char>> buffers;

    std::size_t rcv_index = 0;
    std::size_t rcv_packets = 0;
    std::size_t rcv_size  = 0;
    
    std::size_t lastIndex{0};
    std::size_t loss = 0;
   
    struct mmsghdr msg[max_packets];
    struct iovec msgvec[max_packets];

    buffers.resize(max_packets);

    memset(msg, 0, sizeof(msg));
    memset(msgvec, 0, sizeof(msgvec));
    for (int i = 0; i < max_packets; i++) {
	buffers[i].resize(max_packet_size);

	msgvec[i].iov_base = buffers[i].data();
	msgvec[i].iov_len = buffers[i].size();
	msg[i].msg_hdr.msg_iov = &msgvec[i];
	msg[i].msg_hdr.msg_iovlen = 1;
    }

    if (vma_) {
	vma_->get_socket_rings_fds(server.f_socket, &vma_ring_fd, 1);
	if (vma_ring_fd < 0)  throw "Can't get ring fds";
    }

   printf("ID %d listening %d\n", id, port);

   double coef = 1000. * 1000. * 1000. / 1024. / 1024. / 1024.;
   auto ts_last = std::chrono::high_resolution_clock::now();
   int rbuf = 0;
   while(true){
	int packets;
	struct vma_completion_t vma_comps[max_packets];
	struct vma_packet_desc_t vma_packs[max_packets];

	if (vma_) {
		// Seems crashes on ConnectX-3, requires later cards according to documentation (section 8.2)
	    packets = vma_->socketxtreme_poll(vma_ring_fd, vma_comps, max_packets, 0);
	} else {
	    packets = server.mrecv(max_packets, msg, 1); //timeIntervall_);
	}

	if (packets >= 0) {
	  for (int i = 0; i < packets; i++) {
	    int bytes;
	    unsigned short *buf;
    	    char *ringptr = ringbuf_[rbuf++].data() + id * max_packet_size;
	    if (rbuf == nbufs_) rbuf = 0;
	
	    if (vma_) {
		vma_packs[i] = vma_comps[i].packet;

		switch (vma_comps[i].events) {
                 case VMA_SOCKETXTREME_PACKET:
		    break;
                 case EPOLLERR:
                 case EPOLLRDHUP:
		    printf("Polling error event=0x%lx user_data=%ld\n", vma_comps[i].events, vma_comps[i].user_data);
		    throw "Polling error";
                 default:
            	    printf("Unsupported event=0x%lx user_data=%ld\n", vma_comps[i].events, vma_comps[i].user_data);
            	    throw "Polling error";
		}
		
		bytes = vma_comps[i].packet.total_len;
		buf = reinterpret_cast<unsigned short*>(vma_comps[i].packet.buff_lst->payload);

        	int n_bufs = vma_comps[i].packet.num_bufs;
		struct vma_buff_t *vma_buf = vma_comps[i].packet.buff_lst;
		
		for (int j = 0; j < n_bufs; j++) {
		    memcpy(ringptr, vma_buf->payload, vma_buf->len);
		    ringptr += vma_buf->len;
		    vma_buf = vma_buf->next;
		}
	    } else {
		bytes = msg[i].msg_len;
		buf =  reinterpret_cast<unsigned short*>(msgvec[i].iov_base);

		memcpy(ringptr, buf, bytes);
	    }

	    rcv_packets++;
	    rcv_size += bytes;

    	    std::size_t index =*((std::size_t *)buf);
    	    int diff = index - lastIndex - 1;
    	    if(diff > 0){
        	loss += diff;
    	    }

/*    	    if (port == 4000) {
    		printf("%i:%i:%i:%i,", index, diff, loss, i);
    	    }*/

    	    lastIndex = index;
    	  }
    	  
    	  if (vma_) {
	    vma_->socketxtreme_free_vma_packets(vma_packs, packets);
	  }
    	}
     
	auto ts = std::chrono::high_resolution_clock::now();
	std::chrono::nanoseconds d = ts - ts_last;
	if (d.count() >= 1000000000) {
	    printf("Lost %.2lf%, Received: %i (%zu bytes, %.3lf GBit/s) in %.3lf ms [VMA: %i, port: %i]\n", loss / (double)(lastIndex - rcv_index)*100.0, rcv_packets, rcv_size, 8. * rcv_size * coef / d.count() , 1. * d.count() / 1000000, (vma_?1:0), port);
	    rcv_packets = 0;
	    rcv_size = 0;
	    rcv_index = lastIndex;
	    loss = 0;
	    ts_last = ts;
	}
   }
   
   std::cout << "Lost " << loss << " from " << lastIndex << " packets; (" << loss/(double)lastIndex*100.0 << "%)";
   loss_ += loss;
}