#include <sstp/socketconnectionreceiver.hpp>
#include <common/utility.hpp>
#include <common/stringbuffer.hpp>

SocketConnectionReceiver::SocketConnectionReceiver()
: mSocket(-1), mIsRunnable(true)
{
}


/// @brief After a connection has been accepted the SocketConnectionReceiver is initialized with the incoming socket
/// @param socket 
/// @param internalSocketAddress 
SocketConnectionReceiver::SocketConnectionReceiver(int socket, sockaddr_in internalSocketAddress)
: mSocket(socket), mInternalSocketAddress(internalSocketAddress), mIsRunnable(true)
{
}

/// @brief Initialize a SocketConnectionReceiver.
/// @param socket 
/// @param internalSocketAddress 
void SocketConnectionReceiver::initialize(int socket, sockaddr_in internalSocketAddress)
{
  close();
  mSocket=socket;
  mInternalSocketAddress = internalSocketAddress;
}


/// @brief The destructor will close the socket
SocketConnectionReceiver::~SocketConnectionReceiver()
{ 
  isRunnable(false);
  close();
}

/// @brief Close the socket and set the mSocket variable to -1
/// @param  
void SocketConnectionReceiver::close(void)
{
  if(-1==mSocket)return;
  std::cout << "Closing connection " << mSocket << std::endl;
  ::close(mSocket);
  mSocket=-1;
}

/// @brief The threadFunction will handle the lifetime of the socket connection.  When a QUIT is received the socket will be closed and the thread method will exit
/// @param data 
void SocketConnectionReceiver::threadFunction(int data)
{
  String line;
  while(mIsRunnable)
  {
    readLine(line);
    if(0==line.length())
    {
      std::cout << "Received an empty command" << std::endl;
      break;
    }
    if(line=="QUIT" || line=="quit")
    {
      handleQuit();
      break;
    }
    Block<String> commands = line.split('|');
    if(0==commands.size())continue;
    commands[0].upper();
    if(commands[0]=="PUT")
    {
      handlePut(commands);
    }
    else 
    {
      std::cout << "Unrecognized command >" << line << "<" << std::endl;
    }
  }
  close();
  return;
}

/// @brief The client wants to put a file.  put {filename} {lengthbytes}
/// @param commands [0]=PUT, [1]=filename, [2]=total length
/// This message contains PUT|{filename}|{lengthbytes} followed by as many PCKT|{length} packets as needed to read the entire file contents and save to disk
/// The connection will continue reading packets and saving data to disk until it receives PCKT 0 which signals the end of transmission
/// @return true or false
bool SocketConnectionReceiver::handlePut(Block<String> &commands)
{
  Profiler profiler;
  Array<char> receiveBuffer;
  Block<String> subCommands;
  String strLine;
  String fileName;
  size_t fileLength;
  size_t totalBytesRead=0;
  size_t totalPacketsRead=0;
  size_t availableDiskSpace=0;

  fileName = commands[1];
  fileLength = commands[commands.size()-1].toLong();
  std::cout << "PUT" << " " << fileName << " " << Utility::byteCountToString(fileLength,false) << std::endl;

  availableDiskSpace=Utility::getAvailableDiskSpace(String("./"));
  std::cout << Utility::byteCountToString(availableDiskSpace,false) << " available space on disk" << std::endl;
  if(fileLength > availableDiskSpace)
  {
    std::cout << "Unsufficient space on disk.  Required space " << Utility::byteCountToString(availableDiskSpace,false) << " , available space" << Utility::byteCountToString(availableDiskSpace,false) << std::endl;
    return false;
  }

  FileIO writeFile(fileName, FileIO::ByteOrder::LittleEndian, FileIO::Mode::ReadWrite,FileIO::CreationFlags::CreateAlways);

  if(!writeFile.isOkay())
  {
    std::cout << "Error creating " << fileName << std::endl;
    return false;
  }

  while(true)
  {
    size_t bufferLength=0;
    try
    {
      bufferLength = expectPacket();
    }
    catch(Exception &exception)
    {
      std::cerr << exception.toString() << '\n';
      break;
    }
    if(0==bufferLength)
    {
        std::cout << "Client indicated end of data" << std::endl;
        break;
    }
    receiveBuffer.size(bufferLength);
    size_t bytes_read = read(receiveBuffer);
    totalBytesRead+=bytes_read;
    totalPacketsRead++;
    if(bufferLength!=bytes_read)
    {
      std::cout << "Send/Receive size mismatch.  The client indicated a data length of " << Utility::formatNumber(bufferLength) << " but a data length of " << Utility::formatNumber(bytes_read) << " was received";
      break;
    }
    writeFile.write(&receiveBuffer[0], receiveBuffer.size());
    
    double percent = ((double)totalBytesRead / (double)fileLength)*100.00;
    if(Utility::fmod(percent,10.00,0.0078125))    
    {
      double elapsedTimeSeconds = profiler.elapsed()/1000.00;
      double bytesPerSecond = totalBytesRead / elapsedTimeSeconds;
      String strBytesPerSecond = Utility::byteCountToString(bytesPerSecond);
      std::cout << "Received " << Utility::byteCountToString(totalBytesRead,false) << " of " << Utility::byteCountToString(fileLength,false) << " " << percent << " percent " << strBytesPerSecond << std::endl;
    }
  }
  writeFile.close();
  std::cout << "Transfer complete.  Total packets received " << Utility::formatNumber(totalPacketsRead) << std::endl;
  std::cout << "Received " << Utility::byteCountToString(totalBytesRead,false) << " in " << Utility::formatNumber(profiler.end()) << "(ms)" << std::endl;
  return totalBytesRead==fileLength;
}

/// @brief Read a PCKT message from the socket and return the length.  This message is of the form PCKT|{length} and the method returns the second parameter (length)
/// @param  
/// @return 
size_t SocketConnectionReceiver::expectPacket(void)
{
  Block<String> subCommands;
  String strLine;
  readLine(strLine);
  strLine.makeBlock(subCommands, "|");
  if(subCommands.size()!=2)
  {
    StringBuffer sb;
    sb.append("Received an invalid PCKT command");
    String str=sb.toString();
    std::cout << str << std::endl;
    throw InvalidOperationException(str);
  }
  if(!(subCommands[0]=="PCKT"))
  {
    
    StringBuffer sb;
    sb.append("Unexpected command sequence.");
    sb.append("Expected PCKT but received ").append(subCommands[0]);
    String str = sb.toString();
    std::cout << str << std::endl;
    throw InvalidOperationException(str);
  }
  size_t bufferLength = subCommands[1].toULong();
  return bufferLength;
}

/// @brief Read a '\r\n' terminated string from the socket.  Return the number of bytes read
/// @param line The string to read data into
/// @return 
size_t SocketConnectionReceiver::readLine(String &line)
{
    size_t bytes_read = 0;
    size_t total_bytes = 0;
    char ch;

    char *lpLineBuffer = (char*)line;
    while (total_bytes < line.lengthBytes() - 1)
    { 
        bytes_read = ::recv(mSocket, &ch, 1, 0);
        if (bytes_read <= 0)
        {
            return bytes_read; 
        }
        if (ch=='\r')  // Carriage return
        {
          recv(mSocket, &ch, 1, 0); // consume the line feed
          break;
        }
        lpLineBuffer[total_bytes++] = ch;
    }
    lpLineBuffer[total_bytes] = '\0'; 
    return total_bytes;
}

/// @brief Read bytes from a socket into the provided buffer.
/// @param buffer The buffer must be pre-allocated to a given length.  The read operation will continue until all bytes in the buffer have been read
/// @return 
size_t SocketConnectionReceiver::read(Array<char> &buffer)
{
    size_t bytes_read = 0;
    size_t bytes_to_read = buffer.size();
    size_t total_bytes_read =0;

    char *lpLineBuffer = (char*)&buffer[0];
    while(bytes_to_read>0)
    {
      bytes_read = ::recv(mSocket, lpLineBuffer, bytes_to_read, 0);
      lpLineBuffer+=bytes_read;
      bytes_to_read -= bytes_read;
      total_bytes_read += bytes_read;
    }
    return total_bytes_read;
}

/// @brief Handle a QUIT message... which just displays 
/// @param  
void SocketConnectionReceiver::handleQuit(void)
{
  std::cout << "Received QUIT" << std::endl;
}