/*
 * socket.c: IPTV plugin for the Video Disk Recorder
 *
 * See the README file for copyright information and how to reach the author.
 *
 */

#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <fcntl.h>
#include <unistd.h>

#include <vdr/device.h>

#include "common.h"
#include "config.h"
#include "socket.h"

cIptvSocket::cIptvSocket()
: socketPort(0),
  socketDesc(-1),
  isActive(false)
{
  debug("cIptvSocket::cIptvSocket()\n");
}

cIptvSocket::~cIptvSocket()
{
  debug("cIptvSocket::~cIptvSocket()\n");
  // Close the socket
  CloseSocket();
}

bool cIptvSocket::OpenSocket(const int Port, const bool isUdp)
{
  debug("cIptvSocket::OpenSocket()\n");
  // If socket is there already and it is bound to a different port, it must
  // be closed first
  if (Port != socketPort) {
     debug("cIptvSocket::OpenSocket(): Socket tear-down\n");
     CloseSocket();
     }
  // Bind to the socket if it is not active already
  if (socketDesc < 0) {
     int yes = 1;
     // Create socket
     if (isUdp)
        socketDesc = socket(PF_INET, SOCK_DGRAM, 0);
     else
        socketDesc = socket(PF_INET, SOCK_STREAM, 0);
     ERROR_IF_RET(socketDesc < 0, "socket()", return false);
     // Make it use non-blocking I/O to avoid stuck read calls
     ERROR_IF_FUNC(fcntl(socketDesc, F_SETFL, O_NONBLOCK), "fcntl()",
                   CloseSocket(), return false);
     // Allow multiple sockets to use the same PORT number
     ERROR_IF_FUNC(setsockopt(socketDesc, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) < 0, "setsockopt()",
                   CloseSocket(), return false);
     // Bind socket
     memset(&sockAddr, '\0', sizeof(sockAddr));
     sockAddr.sin_family = AF_INET;
     sockAddr.sin_port = htons(Port);
     sockAddr.sin_addr.s_addr = htonl(INADDR_ANY);
     if (isUdp) {
        int err = bind(socketDesc, (struct sockaddr *)&sockAddr, sizeof(sockAddr));
        ERROR_IF_FUNC(err < 0, "bind()", CloseSocket(), return false);
        }
     // Update socket port
     socketPort = Port;
     }
  return true;
}

void cIptvSocket::CloseSocket(void)
{
  debug("cIptvSocket::CloseSocket()\n");
  // Check if socket exists
  if (socketDesc >= 0) {
     close(socketDesc);
     socketDesc = -1;
     }
}

// UDP socket class
cIptvUdpSocket::cIptvUdpSocket()
{
  debug("cIptvUdpSocket::cIptvUdpSocket()\n");
}

cIptvUdpSocket::~cIptvUdpSocket()
{
  debug("cIptvUdpSocket::~cIptvUdpSocket()\n");
}

bool cIptvUdpSocket::OpenSocket(const int Port)
{
  debug("cIptvUdpSocket::OpenSocket()\n");
  return cIptvSocket::OpenSocket(Port, true);
}

int cIptvUdpSocket::Read(unsigned char* BufferAddr, unsigned int BufferLen)
{
  //debug("cIptvUdpSocket::Read()\n");
  // Error out if socket not initialized
  if (socketDesc <= 0) {
     error("ERROR: Invalid socket in %s\n", __FUNCTION__);
     return -1;
     }
  socklen_t addrlen = sizeof(sockAddr);
  int len = 0;
  // Read data from socket
  if (isActive)
     len = recvfrom(socketDesc, BufferAddr, BufferLen, MSG_DONTWAIT,
                    (struct sockaddr *)&sockAddr, &addrlen);
  if ((len > 0) && (BufferAddr[0] == TS_SYNC_BYTE)) {
     return len;
     }
  else if (len > 3) {
     // http://www.networksorcery.com/enp/rfc/rfc2250.txt
     // version
     unsigned int v = (BufferAddr[0] >> 6) & 0x03;
     // extension bit
     unsigned int x = (BufferAddr[0] >> 4) & 0x01;
     // cscr count
     unsigned int cc = BufferAddr[0] & 0x0F;
     // payload type: MPEG2 TS = 33
     //unsigned int pt = readBuffer[1] & 0x7F;
     // header lenght
     unsigned int headerlen = (3 + cc) * sizeof(uint32_t);
     // check if extension
     if (x) {
        // extension header length
        unsigned int ehl = (((BufferAddr[headerlen + 2] & 0xFF) << 8) |
                            (BufferAddr[headerlen + 3] & 0xFF));
        // update header length
        headerlen += (ehl + 1) * sizeof(uint32_t);
        }
     // Check that rtp is version 2 and payload contains multiple of TS packet data
     if ((v == 2) && (((len - headerlen) % TS_SIZE) == 0) &&
         (BufferAddr[headerlen] == TS_SYNC_BYTE)) {
        // Set argument point to payload in read buffer
        memmove(BufferAddr, &BufferAddr[headerlen], (len - headerlen));
        return (len - headerlen);
        }
     }
  return 0;
}

// TCP socket class
cIptvTcpSocket::cIptvTcpSocket()
{
  debug("cIptvTcpSocket::cIptvTcpSocket()\n");
}

cIptvTcpSocket::~cIptvTcpSocket()
{
  debug("cIptvTcpSocket::~cIptvTcpSocket()\n");
}

bool cIptvTcpSocket::OpenSocket(const int Port)
{
  debug("cIptvTcpSocket::OpenSocket()\n");
  return cIptvSocket::OpenSocket(Port, false);
}

int cIptvTcpSocket::Read(unsigned char* BufferAddr, unsigned int BufferLen)
{
  //debug("cIptvTcpSocket::Read()\n");
  // Error out if socket not initialized
  if (socketDesc <= 0) {
     error("ERROR: Invalid socket in %s\n", __FUNCTION__);
     return -1;
     }
  socklen_t addrlen = sizeof(sockAddr);
  // Read data from socket
  if (isActive)
     return recvfrom(socketDesc, BufferAddr, BufferLen, MSG_DONTWAIT,
                     (struct sockaddr *)&sockAddr, &addrlen);
  return 0;
}