#include <geekos/socket.h>
#include <geekos/malloc.h>
#include <palacios/vmm_types.h>
#include <geekos/ne2k.h>
#include <uip/uip.h>
#include <uip/uip_arp.h>
#include <geekos/vmm_stubs.h>

#define NULL (void *)0


#define BUF ((struct uip_eth_hdr *)&uip_buf[0])

#define MAX_SOCKS 1024
#define BUF_SIZE 1000

struct socket sockets[MAX_SOCKS];

extern void* memcpy(void *dst, const void* src, int n);


int Packet_Received(struct NE2K_Packet_Info* info, uchar_t *pkt) ;

void init_network() {
   int i = 0;
   
   for (i = 0; i < MAX_SOCKS; i++) {
      sockets[i].in_use = 0;
      sockets[i].send_buf = NULL;
      sockets[i].recv_buf = NULL;
   }

    //initiate uIP
    uip_init();
    uip_arp_init();
	
    //setup device driver
    Init_Ne2k(&Packet_Received);


}

static int allocate_socket_fd() {
  int i = 0;
  
  for (i = 0; i < MAX_SOCKS; i++) {
    if (sockets[i].in_use == 0) {
      sockets[i].in_use = 1;
      sockets[i].send_buf = create_ring_buffer(BUF_SIZE);
      if (sockets[i].send_buf == NULL)
	  	return -1;
      sockets[i].recv_buf = create_ring_buffer(BUF_SIZE);
      if (sockets[i].recv_buf == NULL){
	  	free_ring_buffer(sockets[i].send_buf);
	  	return -1;
      }
      return i;
    }
  }

  return -1;
}

static int release_socket_fd(int sockfd){
       if (sockfd >= 0 && sockfd < MAX_SOCKS){
		sockets[sockfd].in_use = 0;
		free_ring_buffer(sockets[sockfd].send_buf);
		free_ring_buffer(sockets[sockfd].recv_buf);
		sockets[sockfd].send_buf = NULL;
		sockets[sockfd].recv_buf = NULL;
       }

	return 0;
}


struct socket * get_socket_from_fd(int fd) {
  return &(sockets[fd]);
}


int connect(const uchar_t ip_addr[4], ushort_t port) {
  int sockfd = -1;
  sockfd = allocate_socket_fd();
  uip_ipaddr_t ipaddr;
  
  if (sockfd == -1) {
    return -1;
  }

  uip_ipaddr(&ipaddr, ip_addr[0], ip_addr[1], ip_addr[2], ip_addr[3]);  
  
  sockets[sockfd].con = uip_connect((uip_ipaddr_t *)&ip_addr, htons(port));

  if (sockets[sockfd].con == NULL){
  	release_socket_fd(sockfd);
	return -1;
  }

  return sockfd;
}

int recv(int sockfd, void * buf, uint_t len){
  uint_t recvlen;

  struct socket *sock = get_socket_from_fd(sockfd);

  // here we need some lock mechnism, just disable interrupt may not work properly because recv() will be run as a kernel thread 
buf_read:
  recvlen = rb_read(sock->recv_buf, buf, len);

  if (recvlen == 0){
  	Wait(&(sock->recv_wait_queue));
	goto buf_read;
  }

  return recvlen;
}

void timer_int_Handler(struct Interrupt_State * state){
	int i;
	//handle the periodic calls of uIP
	for(i = 0; i < UIP_CONNS; ++i) {
	       uip_periodic(i);
		if(uip_len > 0) {
		     //devicedriver_send();
		     NE2K_Transmit(uip_len);
		}
  	}
	for(i = 0; i < UIP_UDP_CONNS; i++) {
		 uip_udp_periodic(i);
		 if(uip_len > 0) {
		     //devicedriver_send();
		     NE2K_Transmit(uip_len);
		}
	}
}

// a series of utilities to handle conncetion states
static void connected(int sockfd){

}

static void closed(int sockfd){

}

static void acked(int sockfd){

}

static void newdata(int sockfd){
  uint_t len;
  char *dataptr;
  uint_t wrlen;
  struct socket *sock;
    
  len = uip_datalen();
  dataptr = (char *)uip_appdata;

  if (len == 0)
  	return;

  sock = get_socket_from_fd(sockfd);

  wrlen = rb_write(sock->recv_buf, dataptr, len);

  if (wrlen < len){ //write error, what should I do?
	return;
  }

  Wake_Up(&(sock->recv_wait_queue));

  return;    

}

// not finished yet
static void
senddata(int sockfd){
  struct socket * sock = get_socket_from_fd(sockfd);
  int mss = uip_mss();
  int pending_bytes = rb_data_len(sock->send_buf);
  int len = (mss < pending_bytes) ? mss: pending_bytes;
  int bytes_read = 0;
  uchar_t * send_buf = uip_appdata;
  
  bytes_read = rb_peek(sock->send_buf, send_buf, len);

  if (bytes_read == 0) {
    // no packet for send
    return;
  }

  uip_send(send_buf, len);
}



//get the socket id by the local tcp port
static int  get_socket_from_port(ushort_t lport) {
  int i;
  
  for (i = 0; i<MAX_SOCKS; i++){
  	if (sockets[i].con->lport == lport) 
		return i;
  }
  
  return -1;
}


void
socket_appcall(void)
{
  int sockfd; 

  sockfd = get_socket_from_port(uip_conn->lport);

  if (sockfd == -1) return;
    
  if(uip_connected()) {
  	connected(sockfd);
  }
  
  if(uip_closed() ||uip_aborted() ||uip_timedout()) {
     closed(sockfd);
     return;
  }
  
  if(uip_acked()) {
     acked(sockfd);
  }
  
  if(uip_newdata()) {
     newdata(sockfd);
  }
  
  if(uip_rexmit() ||
     uip_newdata() ||
     uip_acked() ||
     uip_connected() ||
     uip_poll()) {
     senddata(sockfd);
  }
}



int Packet_Received(struct NE2K_Packet_Info* info, uchar_t *pkt) 
{
	  uip_len = info->size; 
	  
	  //  for (i = 0; i < info->size; i++) {
	  //  uip_buf[i] = *(pkt + i);
	  //}

	  memcpy(uip_buf, pkt, uip_len);
	  Free(pkt);
	  if(BUF->type == htons(UIP_ETHTYPE_ARP)) {
		uip_arp_arpin();
		if (uip_len > 0){
			//ethernet_devicedriver_send();
			NE2K_Transmit(uip_len);
      		}					
	   } else {
		uip_arp_ipin();
		uip_input();
		if(uip_len > 0) {
		       uip_arp_out();
		     //ethernet_devicedriver_send();
			NE2K_Transmit(uip_len);
	       }
	}			  
	  return 0;
}