/*
 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
 * All rights reserved. 
 * 
 * Redistribution and use in source and binary forms, with or without modification, 
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
 * OF SUCH DAMAGE.
 *
 * This file is part of the lwIP TCP/IP stack.
 * 
 * Author: Adam Dunkels <adam@sics.se>
 *
 */

/* This is the part of the API that is linked with
   the application */

#include <string.h>
#include "lwip/opt.h"
#include "lwip/api.h"
#include "lwip/api_msg.h"
#include "lwip/tcpip.h"
#include "lwip/memp.h"

#if !NO_SYS

struct
netbuf *netbuf_new(void)
{
  struct netbuf *buf;

  buf = memp_malloc(MEMP_NETBUF);
  if (buf != NULL) {
    buf->p = NULL;
    buf->ptr = NULL;
    buf->addr = NULL;
    return buf;
  } else {
    return NULL;
  }
}

void
netbuf_delete(struct netbuf *buf)
{
  if (buf != NULL) {
    if (buf->p != NULL) {
      pbuf_free(buf->p);
      buf->p = buf->ptr = NULL;
    }
    memp_free(MEMP_NETBUF, buf);
  }
}

void *
netbuf_alloc(struct netbuf *buf, u16_t size)
{
  /* Deallocate any previously allocated memory. */
  if (buf->p != NULL) {
    pbuf_free(buf->p);
  }
  buf->p = pbuf_alloc(PBUF_TRANSPORT, size, PBUF_RAM);
  if (buf->p == NULL) {
     return NULL;
  }
  buf->ptr = buf->p;
  return buf->p->payload;
}

void
netbuf_free(struct netbuf *buf)
{
  if (buf->p != NULL) {
    pbuf_free(buf->p);
  }
  buf->p = buf->ptr = NULL;
}

err_t
netbuf_ref(struct netbuf *buf, const void *dataptr, u16_t size)
{
  if (buf->p != NULL) {
    pbuf_free(buf->p);
  }
  buf->p = pbuf_alloc(PBUF_TRANSPORT, 0, PBUF_REF);
  if (buf->p == NULL) {
    buf->ptr = NULL;
    return ERR_MEM;
  }
  buf->p->payload = (void*)dataptr;
  buf->p->len = buf->p->tot_len = size;
  buf->ptr = buf->p;
  return ERR_OK;
}

void
netbuf_chain(struct netbuf *head, struct netbuf *tail)
{
  pbuf_chain(head->p, tail->p);
  head->ptr = head->p;
  memp_free(MEMP_NETBUF, tail);
}

err_t
netbuf_data(struct netbuf *buf, void **dataptr, u16_t *len)
{
  if (buf->ptr == NULL) {
    return ERR_BUF;
  }
  *dataptr = buf->ptr->payload;
  *len = buf->ptr->len;
  return ERR_OK;
}

s8_t
netbuf_next(struct netbuf *buf)
{
  if (buf->ptr->next == NULL) {
    return -1;
  }
  buf->ptr = buf->ptr->next;
  if (buf->ptr->next == NULL) {
    return 1;
  }
  return 0;
}

void
netbuf_first(struct netbuf *buf)
{
  buf->ptr = buf->p;
}

void
netbuf_copy_partial(struct netbuf *buf, void *dataptr, u16_t len, u16_t offset)
{
  struct pbuf *p;
  u16_t left;
  u16_t buf_copy_len;

  left = 0;

  if(buf == NULL || dataptr == NULL) {
    return;
  }
  
  /* Note some systems use byte copy if dataptr or one of the pbuf payload pointers are unaligned. */
  for(p = buf->p; len != 0 && p != NULL; p = p->next) {
    if (offset != 0 && offset >= p->len) {
      /* don't copy from this buffer -> on to the next */
      offset -= p->len;
    } else {
      /* copy from this buffer. maybe only partially. */
      buf_copy_len = p->len - offset;
      if (buf_copy_len > len)
          buf_copy_len = len;
      /* copy the necessary parts of the buffer */
      MEMCPY(&((char*)dataptr)[left], &((char*)p->payload)[offset], buf_copy_len);
      left += buf_copy_len;
      len -= buf_copy_len;
      offset = 0;
    }
  }
}

struct
netconn *netconn_new_with_proto_and_callback(enum netconn_type t, u8_t proto,
                                   void (*callback)(struct netconn *, enum netconn_evt, u16_t len))
{
  struct netconn *conn;
  struct api_msg msg;

  conn = memp_malloc(MEMP_NETCONN);
  if (conn == NULL) {
    return NULL;
  }
  
  conn->err = ERR_OK;
  conn->type = t;
  conn->pcb.tcp = NULL;

  if ((conn->mbox = sys_mbox_new()) == SYS_MBOX_NULL) {
    memp_free(MEMP_NETCONN, conn);
    return NULL;
  }
  conn->recvmbox = SYS_MBOX_NULL;
  conn->acceptmbox = SYS_MBOX_NULL;
  conn->sem = sys_sem_new(0);
  if (conn->sem == SYS_SEM_NULL) {
    sys_mbox_free(conn->mbox);
    memp_free(MEMP_NETCONN, conn);
    return NULL;
  }
  conn->state        = NETCONN_NONE;
  conn->socket       = 0;
  conn->callback     = callback;
  conn->recv_avail   = 0;
#if LWIP_SO_RCVTIMEO
  conn->recv_timeout = 0;
#endif /* LWIP_SO_RCVTIMEO */

  msg.function = do_newconn;
  msg.msg.msg.raw_proto = proto;
  msg.msg.conn = conn;
  tcpip_apimsg(&msg);  

  if ( conn->err != ERR_OK ) {
    sys_sem_free(conn->sem);
    sys_mbox_free(conn->mbox);
    memp_free(MEMP_NETCONN, conn);
    return NULL;
  }

  return conn;
}

struct
netconn *netconn_new(enum netconn_type t)
{
  return netconn_new_with_proto_and_callback(t,0,NULL);
}

struct
netconn *netconn_new_with_callback(enum netconn_type t,
                                   void (*callback)(struct netconn *, enum netconn_evt, u16_t len))
{
  return netconn_new_with_proto_and_callback(t,0,callback);
}

err_t
netconn_delete(struct netconn *conn)
{
  struct api_msg msg;
  void *mem;
  
  if (conn == NULL) {
    return ERR_OK;
  }
  
  msg.function = do_delconn;
  msg.msg.conn = conn;
  tcpip_apimsg(&msg);

  /* Drain the recvmbox. */
  if (conn->recvmbox != SYS_MBOX_NULL) {
    while (sys_mbox_tryfetch(conn->recvmbox, &mem) != SYS_MBOX_EMPTY) {
      if (conn->type == NETCONN_TCP) {
        if(mem != NULL)
          pbuf_free((struct pbuf *)mem);
      } else {
        netbuf_delete((struct netbuf *)mem);
      }
    }
    sys_mbox_free(conn->recvmbox);
    conn->recvmbox = SYS_MBOX_NULL;
  }
 

  /* Drain the acceptmbox. */
  if (conn->acceptmbox != SYS_MBOX_NULL) {
    while (sys_mbox_tryfetch(conn->acceptmbox, &mem) != SYS_MBOX_EMPTY) {
      netconn_delete((struct netconn *)mem);
    }
    sys_mbox_free(conn->acceptmbox);
    conn->acceptmbox = SYS_MBOX_NULL;
  }

  sys_mbox_free(conn->mbox);
  conn->mbox = SYS_MBOX_NULL;

  if (conn->sem != SYS_SEM_NULL) {
    sys_sem_free(conn->sem);
    /* conn->sem = SYS_SEM_NULL; */
  }

  memp_free(MEMP_NETCONN, conn);
  return ERR_OK;
}

enum netconn_type
netconn_type(struct netconn *conn)
{
  return conn->type;
}

err_t
netconn_peer(struct netconn *conn, struct ip_addr *addr, u16_t *port)
{
  switch (conn->type) {
  case NETCONN_RAW:
    /* return an error as connecting is only a helper for upper layers */
    return ERR_CONN;
  case NETCONN_UDPLITE:
  case NETCONN_UDPNOCHKSUM:
  case NETCONN_UDP:
    if (conn->pcb.udp == NULL ||
  ((conn->pcb.udp->flags & UDP_FLAGS_CONNECTED) == 0))
     return ERR_CONN;
    *addr = (conn->pcb.udp->remote_ip);
    *port = conn->pcb.udp->remote_port;
    break;
  case NETCONN_TCP:
    if (conn->pcb.tcp == NULL)
      return ERR_CONN;
    *addr = (conn->pcb.tcp->remote_ip);
    *port = conn->pcb.tcp->remote_port;
    break;
  }
  return (conn->err = ERR_OK);
}

err_t
netconn_addr(struct netconn *conn, struct ip_addr **addr, u16_t *port)
{
  switch (conn->type) {
  case NETCONN_RAW:
    *addr = &(conn->pcb.raw->local_ip);
    *port = conn->pcb.raw->protocol;
    break;
  case NETCONN_UDPLITE:
  case NETCONN_UDPNOCHKSUM:
  case NETCONN_UDP:
    *addr = &(conn->pcb.udp->local_ip);
    *port = conn->pcb.udp->local_port;
    break;
  case NETCONN_TCP:
    *addr = &(conn->pcb.tcp->local_ip);
    *port = conn->pcb.tcp->local_port;
    break;
  }
  return (conn->err = ERR_OK);
}

err_t
netconn_bind(struct netconn *conn, struct ip_addr *addr, u16_t port)
{
  struct api_msg msg;

  if (conn == NULL) {
    return ERR_VAL;
  }

  if (conn->type != NETCONN_TCP &&
     conn->recvmbox == SYS_MBOX_NULL) {
    if ((conn->recvmbox = sys_mbox_new()) == SYS_MBOX_NULL) {
      return ERR_MEM;
    }
  }
  
  msg.function = do_bind;
  msg.msg.conn = conn;
  msg.msg.msg.bc.ipaddr = addr;
  msg.msg.msg.bc.port = port;
  tcpip_apimsg(&msg);
  return conn->err;
}


err_t
netconn_connect(struct netconn *conn, struct ip_addr *addr, u16_t port)
{
  struct api_msg msg;
  
  if (conn == NULL) {
    return ERR_VAL;
  }

  if (conn->recvmbox == SYS_MBOX_NULL) {
    if ((conn->recvmbox = sys_mbox_new()) == SYS_MBOX_NULL) {
      return ERR_MEM;
    }
  }
  
  msg.function = do_connect;
  msg.msg.conn = conn;  
  msg.msg.msg.bc.ipaddr = addr;
  msg.msg.msg.bc.port = port;
  tcpip_apimsg(&msg);
  return conn->err;
}

err_t
netconn_disconnect(struct netconn *conn)
{
  struct api_msg msg;
  
  if (conn == NULL) {
    return ERR_VAL;
  }

  msg.function = do_disconnect;
  msg.msg.conn = conn;  
  tcpip_apimsg(&msg);
  return conn->err;

}

err_t
netconn_listen(struct netconn *conn)
{
  struct api_msg msg;

  if (conn == NULL) {
    return ERR_VAL;
  }

  if (conn->acceptmbox == SYS_MBOX_NULL) {
    if ((conn->acceptmbox = sys_mbox_new()) == SYS_MBOX_NULL) {
      return ERR_MEM;
    }
  }
  
  msg.function = do_listen;
  msg.msg.conn = conn;
  tcpip_apimsg(&msg);
  return conn->err;
}

struct netconn *
netconn_accept(struct netconn *conn)
{
  struct netconn *newconn;
  
  if (conn == NULL) {
    return NULL;
  }
  
  sys_mbox_fetch(conn->acceptmbox, (void *)&newconn);
  /* Register event with callback */
  if (conn->callback)
      (*conn->callback)(conn, NETCONN_EVT_RCVMINUS, 0);
  
  return newconn;
}

struct netbuf *
netconn_recv(struct netconn *conn)
{
  struct api_msg msg;
  struct netbuf *buf = NULL;
  struct pbuf *p;
  u16_t len;
  
  if (conn == NULL) {
    return NULL;
  }

  if (conn->recvmbox == SYS_MBOX_NULL) {
    if ((conn->recvmbox = sys_mbox_new()) == SYS_MBOX_NULL) {
      conn->err = ERR_CONN;
      return NULL;
    }
  }

  if (conn->err != ERR_OK) {
    return NULL;
  }

  if (conn->type == NETCONN_TCP) {
#if LWIP_TCP
    if (conn->pcb.tcp->state == LISTEN) {
      conn->err = ERR_CONN;
      return NULL;
    }

    buf = memp_malloc(MEMP_NETBUF);

    if (buf == NULL) {
      conn->err = ERR_MEM;
      return NULL;
    }
    
    sys_mbox_fetch(conn->recvmbox, (void *)&p);

    if (p != NULL)
    {
        len = p->tot_len;
        conn->recv_avail -= len;
    }
    else
        len = 0;
    
    /* Register event with callback */
      if (conn->callback)
        (*conn->callback)(conn, NETCONN_EVT_RCVMINUS, len);

    /* If we are closed, we indicate that we no longer wish to receive
       data by setting conn->recvmbox to SYS_MBOX_NULL. */
    if (p == NULL) {
      memp_free(MEMP_NETBUF, buf);
      sys_mbox_free(conn->recvmbox);
      conn->recvmbox = SYS_MBOX_NULL;
      return NULL;
    }

    buf->p = p;
    buf->ptr = p;
    buf->port = 0;
    buf->addr = NULL;

    /* Let the stack know that we have taken the data. */
    msg.function = do_recv;
    msg.msg.conn = conn;
    if (buf != NULL) {
      msg.msg.msg.len = buf->p->tot_len;
    } else {
      msg.msg.msg.len = 1;
    }
    tcpip_apimsg(&msg);
#endif /* LWIP_TCP */
  } else {
#if (LWIP_UDP || LWIP_RAW)
#if LWIP_SO_RCVTIMEO
    sys_mbox_fetch_timeout(conn->recvmbox, (void *)&buf, conn->recv_timeout);
#else
    sys_mbox_fetch(conn->recvmbox, (void *)&buf);
#endif /* LWIP_SO_RCVTIMEO*/
    if (buf!=NULL)
     { conn->recv_avail -= buf->p->tot_len;
       /* Register event with callback */
       if (conn->callback)
           (*conn->callback)(conn, NETCONN_EVT_RCVMINUS, buf->p->tot_len);
     }
#endif /* (LWIP_UDP || LWIP_RAW) */
  }
    
  LWIP_DEBUGF(API_LIB_DEBUG, ("netconn_recv: received %p (err %d)\n", (void *)buf, conn->err));

  return buf;
}

err_t
netconn_sendto(struct netconn *conn, struct netbuf *buf, struct ip_addr *addr, u16_t port)
{ if (buf!=NULL) {
    buf->addr = addr;
    buf->port = port;
    return netconn_send( conn, buf);
  }
  return ERR_VAL;
} 

err_t
netconn_send(struct netconn *conn, struct netbuf *buf)
{
  struct api_msg msg;

  if (conn == NULL) {
    return ERR_VAL;
  }

  if (conn->err != ERR_OK) {
    return conn->err;
  }

  LWIP_DEBUGF(API_LIB_DEBUG, ("netconn_send: sending %d bytes\n", buf->p->tot_len));
  msg.function = do_send;
  msg.msg.conn = conn;
  msg.msg.msg.b = buf;
  tcpip_apimsg(&msg);
  return conn->err;
}

err_t
netconn_write(struct netconn *conn, const void *dataptr, u16_t size, u8_t copy)
{
  struct api_msg msg;
  u16_t len, sndbuf;
  
  if (conn == NULL) {
    return ERR_VAL;
  }

  if (conn->err != ERR_OK) {
    return conn->err;
  }

  msg.function = do_write;
  msg.msg.conn = conn;

  conn->state = NETCONN_WRITE;
  while (conn->err == ERR_OK && size > 0) {
    msg.msg.msg.w.dataptr = dataptr;
    msg.msg.msg.w.copy = copy;
    
    if (conn->type == NETCONN_TCP) {
      while ((sndbuf = tcp_sndbuf(conn->pcb.tcp)) == 0) {
        sys_sem_wait(conn->sem);
        if (conn->err != ERR_OK) {
          goto ret;
        }
      }
      if (size > sndbuf) {
        /* We cannot send more than one send buffer's worth of data at a time. */
        len = sndbuf;
      } else {
        len = size;
      }
    } else {
      len = size;
    }
    
    LWIP_DEBUGF(API_LIB_DEBUG, ("netconn_write: writing %d bytes (%d)\n", len, copy));
    msg.msg.msg.w.len = len;
    tcpip_apimsg(&msg);
    if (conn->err == ERR_OK) {
      dataptr = (void *)((u8_t *)dataptr + len);
      size -= len;
    } else if (conn->err == ERR_MEM) {
      conn->err = ERR_OK;
      sys_sem_wait(conn->sem);
    } else {
      goto ret;
    }
  }
 ret:
  conn->state = NETCONN_NONE;
  
  return conn->err;
}

err_t
netconn_close(struct netconn *conn)
{
  struct api_msg msg;

  if (conn == NULL) {
    return ERR_VAL;
  }

  conn->state = NETCONN_CLOSE;
 again:
  msg.function = do_close;
  msg.msg.conn = conn;
  tcpip_apimsg(&msg);
  if (conn->err == ERR_MEM && conn->sem != SYS_SEM_NULL) {
    sys_sem_wait(conn->sem);
    goto again;
  }
  conn->state = NETCONN_NONE;
  return conn->err;
}

#if LWIP_IGMP
err_t
netconn_join_leave_group (struct netconn *conn,
                          struct ip_addr *multiaddr,
                          struct ip_addr *interface,
                          u16_t join_or_leave)
{
  struct api_msg msg;
  struct ip_addr *ipaddr[2];

  if (conn == NULL) {
    return ERR_VAL;
  }

  if (conn->err != ERR_OK) {
    return conn->err;
  }

  ipaddr[0] = multiaddr;
  ipaddr[1] = interface;

  msg.function = do_join_leave_group;
  msg.msg.conn = conn;
  msg.msg.msg.bc.ipaddr = (struct ip_addr *)ipaddr;
  msg.msg.msg.bc.port = join_or_leave; /* misusing the port field */
  tcpip_apimsg(&msg);
  return conn->err;
}
#endif /* LWIP_IGMP */

err_t
netconn_err(struct netconn *conn)
{
  return conn->err;
}

#endif /* !NO_SYS */