#include <sys/types.h>
#include <sys/socket.h>
#include <stdlib.h>
#include <errno.h>
#include <limits.h>

#include "agent_sender.h"
#include "packet.h"
#include "log.h"

CAgentSender::CAgentSender(int f):
    fd(f),
    vec(NULL),
    totalVec(1024),
    currVec(0),
    packet(NULL),
    totalPacket(512),
    currPacket(0),
    totalLen(0),
    sended(0),
    leftLen(0),
    broken(0)
{
}

CAgentSender::~CAgentSender()
{
    /* fd will closed by CClientAgent */
    for(uint32_t j = 0; j < currPacket; j++)
    {
        if(packet[j])
        {
            packet[j]->FreeResultBuff();
            delete packet[j];
        }
    }
    if(vec)
        free(vec);
    if(packet)
        free(packet);
}

int CAgentSender::Init()
{
    vec = (struct iovec *)malloc(1024 * sizeof(struct iovec));    
    if(NULL == vec)
    {
        broken = 1;
        return -1;
    }

    if(vec)
    {
        packet = (CPacket **)malloc(512 * sizeof(CPacket *));
        if(NULL == packet)
        {
            broken = 1;
            return -1;
        }
    }

    return 0;
}

int CAgentSender::AddPacket(CPacket * pkt)
{
    if(currVec == totalVec)
    {
        vec = (struct iovec *)realloc(vec, totalVec * 2 * sizeof(struct iovec));
        if(NULL == vec)
        {
            broken = 1;
            return -ENOMEM;
        }
        totalVec *= 2;
    }

    if(currPacket == totalPacket)
    {
        packet = (CPacket **)realloc(packet, totalPacket * 2 * sizeof(CPacket *));
        if(NULL == packet)
        {
            broken = 1;
            return -ENOMEM;
        }
        totalPacket *= 2;
    }

    for(int i = 0; i < pkt->VecCount(); i++)
    {
        vec[currVec++] = pkt->IOVec()[i];
    }
    packet[currPacket++] = pkt;
    leftLen += pkt->Bytes();

    return 0;
}

int CAgentSender::Send()
{
    if(0 == leftLen)
        return 0;

    int sd;
    struct msghdr msgh;
    uint32_t cursor = 0;
    struct iovec * v = vec;
    uint32_t pcursor = 0;
    CPacket ** p = packet;

    msgh.msg_name = NULL;
    msgh.msg_namelen = 0;
    msgh.msg_iov = vec;
    msgh.msg_iovlen = currVec;
    msgh.msg_control = NULL;
    msgh.msg_controllen = 0;
    msgh.msg_flags = 0;

    sd = sendmsg(fd, &msgh, MSG_DONTWAIT|MSG_NOSIGNAL);
    if(sd < 0)
    {
        if(EINTR == errno || EAGAIN == errno || EINPROGRESS == errno)
            return 0;
        log_error("agent sender send error. errno: %d, left len: %d, currVec: %d, IOV_MAX: %d", errno, leftLen, currVec, IOV_MAX);
        broken = 1;
        return -1;
    }

    totalLen = leftLen;
    sended = sd;
    leftLen -= sended;

    if(0 == sd)
        return 0;

    while(cursor < currVec && (uint32_t)sd >= v->iov_len)
    {
        sd -= v->iov_len;
        cursor++;
        v++;
        (*p)->SendDoneOneVec();
        if((*p)->IsSendDone())
        {
            (*p)->FreeResultBuff();	    
            delete *p;
            pcursor++;
            p++;
        }
    }

    if(sd > 0)
    {
        v->iov_base = (char *)v->iov_base + sd;
        v->iov_len -= sd;
    }

    memmove((void *)vec, (void *)(vec + cursor), (currVec - cursor) * sizeof(struct iovec));
    currVec -= cursor;

    memmove((void *)packet, (void *)(packet + pcursor), (currPacket - pcursor) * sizeof(CPacket *));
    currPacket -= pcursor;

    return 0;
}