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

namespace core {

   Socket::Socket(EPoll &ePoll) : ePoll(ePoll) {
      coreutils::Log(coreutils::LOG_DEBUG_2) << "BMASocket object created.";
      buffer = (char *)malloc(4096);
      length = 4096;
   }
   
   Socket::~Socket() {
      ePoll.unregisterSocket(this);
      close(descriptor);
      free(buffer);
      onUnregister();
   }
   
   void Socket::setDescriptor(int descriptor) {
      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();
   }
   
   int Socket::getDescriptor() {
      return descriptor;
   }
   
   void Socket::setBufferSize(int length) {
      buffer = (char *)realloc(buffer, length);
      this->length = length;
   }
   
   void Socket::onRegister() {}

   void Socket::onRegistered() {}
   
   void Socket::onUnregister() {}
   
   void Socket::eventReceived(struct epoll_event event) {
               
      if(event.events & EPOLLRDHUP) {
         readHangup = true;
         enable(false);
         shutdown();
         return;
      }

      if(event.events & EPOLLIN) 
        receiveData(buffer, length);                  
            
      if(event.events & EPOLLOUT) 
        writeSocket();

      if(event.events & EPOLLHUP) {
         shutdown();
         return;
      }
         
      enable(true);
   }
   
   void Socket::enable(bool mode) {
      if(mode) {
         if(fifo.empty()) {
            if(!readHangup) {
               active ? resetRead(): setRead();
            }
         }
         else {
            active ? resetReadWrite(): setReadWrite();
         }
         active = true;
      }
      else 
        clear();
   }
   
   void Socket::receiveData(char *buffer, int bufferLength) {
      
      if(bufferLength <= 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, bufferLength)) >= 0) 
        onDataReceived(std::string(buffer, len));       
      else {
	 
	 error = errno;
	 
	 switch (error) {
	    
	    // When a listening socket receives a connection 
	    // request we get one of these.
      	    // 
	  case ENOTCONN: 
            onDataReceived(std::string(buffer, 0));                
            break;
	    
	  case ECONNRESET:
            break;
	    
	  default:
            throw coreutils::Exception("Error in read of data from socket.", __FILE__, __LINE__, error);
	 }
      }
   }
   
//   void Socket::onConnected() {
//   }
   
   void Socket::writeSocket() {
      lock.lock();
      if(fifo.size() > 0) {
         ::write(descriptor, fifo.front().c_str(), fifo.front().length());
         fifo.pop();
         enable(true);
      }
      lock.unlock();
   }
   
   void Socket::write(std::string data) {
      lock.lock();
      fifo.emplace(data);   
      enable(true);
      lock.unlock();
   }
   
   void Socket::output(std::stringstream &out) {
      out << "|" << descriptor << "|";
   }
   
   void Socket::setRead() {
      event.data.fd = descriptor;
      event.events = EPOLLIN | EPOLLONESHOT | EPOLLRDHUP | EPOLLET;   
      epoll_ctl(ePoll.getDescriptor(), EPOLL_CTL_DEL, descriptor, NULL);  
      epoll_ctl(ePoll.getDescriptor(), EPOLL_CTL_ADD, event.data.fd, &event);      
   }
   
   void Socket::setWrite() {
      event.data.fd = descriptor;
      event.events = EPOLLOUT | EPOLLONESHOT | EPOLLRDHUP | EPOLLET;   
      epoll_ctl(ePoll.getDescriptor(), EPOLL_CTL_DEL, descriptor, NULL);  
      epoll_ctl(ePoll.getDescriptor(), EPOLL_CTL_ADD, descriptor, &event);      
   }
   
   void Socket::setReadWrite() {
      event.data.fd = descriptor;
      event.events = EPOLLIN | EPOLLWRNORM | EPOLLONESHOT | EPOLLRDHUP | EPOLLET;   
      epoll_ctl(ePoll.getDescriptor(), EPOLL_CTL_DEL, descriptor, NULL);  
      epoll_ctl(ePoll.getDescriptor(), EPOLL_CTL_ADD, descriptor, &event);      
   }
   
   void Socket::resetRead() {
      event.data.fd = descriptor;
      event.events = EPOLLIN | EPOLLONESHOT | EPOLLRDHUP | EPOLLET;   
      epoll_ctl(ePoll.getDescriptor(), EPOLL_CTL_MOD, descriptor, &event);      
   }
   
   void Socket::resetWrite() {
      event.data.fd = descriptor;
      event.events = EPOLLOUT | EPOLLONESHOT | EPOLLRDHUP | EPOLLET;
      epoll_ctl(ePoll.getDescriptor(), EPOLL_CTL_MOD, descriptor, &event);      
   }
   
   void Socket::resetReadWrite() {
      event.data.fd = descriptor;
      event.events = EPOLLIN | EPOLLOUT | EPOLLONESHOT | EPOLLRDHUP | EPOLLET;
      epoll_ctl(ePoll.getDescriptor(), EPOLL_CTL_MOD, descriptor, &event);      
   }
   
   void Socket::clear() {
      epoll_ctl(ePoll.getDescriptor(), EPOLL_CTL_DEL, descriptor, NULL);
   }
   
   void Socket::shutdown() {
      coreutils::Log(coreutils::LOG_DEBUG_2) << "Shutdown requested on socket " << descriptor << ".";
      shutDown = true;
		enable(false);
		delete this;
   }
   
}