#include "EPoll.h"
#include "Socket.h"
#include "Exception.h"
#include "Log.h"

namespace core {

   Socket::Socket(EPoll &ePoll, std::string text) : ePoll(ePoll), text(text) {
      coreutils::Log(coreutils::LOG_DEBUG_2) << "BMASocket object created [" << text << "].";
      buffer = (char *)malloc(4096);
      length = 4096;
   }
   
   Socket::~Socket() {
      free(buffer);
      if(descriptor == -1)
	return;           
      onUnregister();
      ePoll.unregisterSocket(this);
      coreutils::Log(coreutils::LOG_DEBUG_3) << "Socket destroyed for socket " << descriptor << ".";
      close(descriptor);
   }
   
   void Socket::setDescriptor(int descriptor) {
      if((descriptor == -1) && (errno == 24)) {
	 shutdown("Too many files open");
	 coreutils::Exception("Too many files open. Refusing connection.");;
      }
      lock.lock();
      coreutils::Log(coreutils::LOG_DEBUG_3) << "Descriptor set to " << descriptor << " for Socket.";
      if(descriptor < 3)
        throw coreutils::Exception("Descriptor out of range", __FILE__, __LINE__);
      this->descriptor = descriptor;
      onRegister();
      ePoll.registerSocket(this);
      onRegistered();
      lock.unlock();
   }
   
   int Socket::getDescriptor() {
      return descriptor;
   }
   
   void Socket::setBufferSize(int length) {
      this->length = length;
      buffer = (char *)realloc(buffer, length);
   }

   int Socket::getBufferSize() {
      return length;
   }
  
   void Socket::onRegister() {}

   void Socket::onRegistered() {}
   
   void Socket::onUnregister() {}

   void Socket::onUnregistered() {}
   
   bool Socket::eventReceived(struct epoll_event event) {
	   
      lock.lock();
      
      if(event.events & EPOLLRDHUP) {
         readHangup = true;
         shutdown("hangup received");
      	lock.unlock();
         return false;
      }

      if(event.events & EPOLLIN) {
     	   receiveData(buffer);                  
      }
      
      if(event.events & EPOLLWRNORM) {
	      writeSocket();
      }

      if(event.events & EPOLLHUP) {
         shutdown();
	      lock.unlock();
	      return false;
      }

      lock.unlock();

      reset = true;      
      return reset;
   }
   
   void Socket::onDataReceived(std::string data) {
      throw coreutils::Exception("Need to override onDataReceived.", __FILE__, __LINE__, -1);
   }
      
   void Socket::onDataReceived(coreutils::ZString data) {
      onDataReceived(std::string(data.getData(), data.getLength()));                   
   }
   
   void Socket::receiveData(coreutils::ZString buffer) {
      
      if(buffer.getLength() <= 0)
        throw coreutils::Exception("Request to receive data with a zero buffer length.", __FILE__, __LINE__, -1);
      
      int len;
      int error = -1;
      
      if((len = ::read(getDescriptor(), buffer.getData(), buffer.getLength())) >= 0) {	   
    	   onDataReceived(buffer);       
      }
      else {
	 
	 error = errno;
	 
	 switch (error) {
	    
	    // When a listening socket receives a connection 
	    // request we get one of these.
      	    // 
	  case ENOTCONN: 
            onDataReceived(std::string(buffer.getData(), 0));                
            break;
	    
	  case ECONNRESET:
            break;
	    
	  default:
            throw coreutils::Exception("Error in read of data from socket.", __FILE__, __LINE__, error);
	 }
      }
   }
   
   void Socket::writeSocket() {      
      if(fifo.size() > 0) {
	 outlock.lock();
	 coreutils::Log(coreutils::LOG_DEBUG_3) << "Writing data to socket " << getDescriptor() << " [" << fifo.front() << "].";
         ::write(descriptor, fifo.front().c_str(), fifo.front().length());
         fifo.pop();
	 if(shutDown && !needsToWrite())
	   delete this;
	 outlock.unlock();
      }
   }
   
   int Socket::write(std::string data) {
      coreutils::Log(coreutils::LOG_DEBUG_3) << "Writing data to socket " << getDescriptor() << " buffer [" << data << "].";
      outlock.lock();
      fifo.emplace(data);   
      coreutils::Log(coreutils::LOG_DEBUG_4) << "Enabling write on socket " << getDescriptor() << " with " << fifo.size() << " entries to write.";
      outlock.unlock();
      ePoll.resetSocket(this);
      return 1;
   }
   
   void Socket::output(std::stringstream &out) {
      out << "|" << descriptor << "|";
   }

   bool Socket::needsToWrite() {
      coreutils::Log(coreutils::LOG_DEBUG_4) << "Socket " << getDescriptor() << " needs to write is " << (fifo.size() > 0) << ".";
      return fifo.size() > 0;
   }   
   
   void Socket::shutdown(std::string text) {
      coreutils::Log(coreutils::LOG_DEBUG_2) << "Shutdown requested on socket " << descriptor << " with reason " << text << ".";
      shutDown = true;
      reset = false;
      if(!needsToWrite()) {
	 delete this;
      }
      
   }
   
}