/*
 * Copyright (c) 2014, Thingsquare, http://www.thingsquare.com/.
 * 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. Neither the name of the copyright holder nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``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
 * COPYRIGHT HOLDER OR CONTRIBUTORS 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.
 *
 */

#include "websocket-http-client.h"
#include "net/ip/uiplib.h"
#include "net/ip/resolv.h"

#include "ip64-addr.h"

#include <stdio.h>
#include <string.h>

#define DEBUG DEBUG_NONE
#include "net/ip/uip-debug.h"

enum {
  STATE_WAITING_FOR_HEADER,
  STATE_WAITING_FOR_CONNECTED,
  STATE_STEADY_STATE,
};
/*---------------------------------------------------------------------------*/
static void
send_get(struct websocket_http_client_state *s)
{
  struct tcp_socket *tcps;

  tcps = &s->s;
  tcp_socket_send_str(tcps, "GET ");
  tcp_socket_send_str(tcps, s->file);
  tcp_socket_send_str(tcps, " HTTP/1.1\r\n");
  tcp_socket_send_str(tcps, "Host: ");
  tcp_socket_send_str(tcps, s->host);
  tcp_socket_send_str(tcps, "\r\n");
  if(strlen(s->header) > 0) {
    tcp_socket_send_str(tcps, s->header);
  }
  tcp_socket_send_str(tcps,
                      "Connection: Upgrade\r\n"
                      "Upgrade: websocket\r\n"
                      "Sec-WebSocket-Key: x3JJHMbDL1EzLkh9GBhXDw==\r\n"
                      "Sec-WebSocket-Version: 13\r\n"
                      "Sec-WebSocket-Protocol:");
  tcp_socket_send_str(tcps, s->subprotocol);
  tcp_socket_send_str(tcps, "\r\n");
  tcp_socket_send_str(tcps, "\r\n");
  PRINTF("websocket-http-client: send_get(): output buffer left %d\n", tcp_socket_max_sendlen(tcps));
}
/*---------------------------------------------------------------------------*/
static void
send_connect(struct websocket_http_client_state *s)
{
  struct tcp_socket *tcps;
  char buf[20];

  tcps = &s->s;
  tcp_socket_send_str(tcps, "CONNECT ");
  tcp_socket_send_str(tcps, s->host);
  tcp_socket_send_str(tcps, ":");
  sprintf(buf, "%d", s->port);
  tcp_socket_send_str(tcps, buf);
  tcp_socket_send_str(tcps, " HTTP/1.1\r\n");
  tcp_socket_send_str(tcps, "Host: ");
  tcp_socket_send_str(tcps, s->host);
  tcp_socket_send_str(tcps, "\r\n");
  tcp_socket_send_str(tcps, "Proxy-Connection: Keep-Alive\r\n\r\n");
}
/*---------------------------------------------------------------------------*/
static void
event(struct tcp_socket *tcps, void *ptr,
      tcp_socket_event_t e)
{
  struct websocket_http_client_state *s = ptr;

  if(e == TCP_SOCKET_CONNECTED) {
    if(s->proxy_port != 0) {
      send_connect(s);
    } else {
      send_get(s);
    }
  } else if(e == TCP_SOCKET_CLOSED) {
    websocket_http_client_closed(s);
  } else if(e == TCP_SOCKET_TIMEDOUT) {
    websocket_http_client_timedout(s);
  } else if(e == TCP_SOCKET_ABORTED) {
    websocket_http_client_aborted(s);
  } else if(e == TCP_SOCKET_DATA_SENT) {
  }
}
/*---------------------------------------------------------------------------*/
static int
parse_header_byte(struct websocket_http_client_state *s,
                  uint8_t b)
{
  static const char *endmarker = "\r\n\r\n";

  PT_BEGIN(&s->parse_header_pt);

  /* Skip the first part of the HTTP response */
  while(b != ' ') {
    PT_YIELD(&s->parse_header_pt);
  }

  /* Skip the space that follow the first part */
  PT_YIELD(&s->parse_header_pt);

  /* Read the first three bytes that consistute the HTTP status code. */
  s->http_status = (b - '0');
  PT_YIELD(&s->parse_header_pt);
  s->http_status = s->http_status * 10 + (b - '0');
  PT_YIELD(&s->parse_header_pt);
  s->http_status = s->http_status * 10 + (b - '0');

  if((s->proxy_port != 0 && !(s->http_status == 200 || s->http_status == 101)) ||
     (s->proxy_port == 0 && s->http_status != 101)) {
    /* This is a websocket request, so the server should have answered
       with a 101 Switching protocols response. */
    PRINTF("Websocket HTTP client didn't get the 101 status code (got %d), closing connection\n",
           s->http_status);
    websocket_http_client_close(s);
    while(1) {
      PT_YIELD(&s->parse_header_pt);
    }
  }


  /* Keep eating header bytes until we reach the end of it. The end is
     indicated by the string "\r\n\r\n". We don't actually look at any
     of the headers.

     The s->i variable contains the number of consecutive bytes
     matched. If we match the total length of the string, we stop.
  */

  s->i = 0;
  do {
    PT_YIELD(&s->parse_header_pt);
    if(b == (uint8_t)endmarker[s->i]) {
      s->i++;
    } else {
      s->i = 0;
    }
  } while(s->i < strlen(endmarker));

  if(s->proxy_port != 0 && s->state == STATE_WAITING_FOR_HEADER) {
    send_get(s);
    s->state = STATE_WAITING_FOR_CONNECTED;
  } else {
    s->state = STATE_STEADY_STATE;
    websocket_http_client_connected(s);
  }
  PT_END(&s->parse_header_pt);
}
/*---------------------------------------------------------------------------*/
static int
input(struct tcp_socket *tcps, void *ptr,
      const uint8_t *inputptr, int inputdatalen)
{
  struct websocket_http_client_state *s = ptr;

  if(s->state == STATE_WAITING_FOR_HEADER ||
     s->state == STATE_WAITING_FOR_CONNECTED) {
    int i;
    for(i = 0; i < inputdatalen; i++) {
      parse_header_byte(s, inputptr[i]);
      if(s->state == STATE_STEADY_STATE) {
        i++;
        break;
      }
    }

    if(i < inputdatalen && s->state == STATE_STEADY_STATE) {
      websocket_http_client_datahandler(s, &inputptr[i], inputdatalen - i);
    }
  } else {
    websocket_http_client_datahandler(s, inputptr, inputdatalen);
  }

  return 0; /* all data consumed */
}
/*---------------------------------------------------------------------------*/
int
websocket_http_client_register(struct websocket_http_client_state *s,
                               const char *host,
                               uint16_t port,
                               const char *file,
                               const char *subprotocol,
                               const char *header)
{
  if(host == NULL) {
    return -1;
  }
  strncpy(s->host, host, sizeof(s->host));

  if(file == NULL) {
    return -1;
  }
  strncpy(s->file, file, sizeof(s->file));

  if(subprotocol == NULL) {
    return -1;
  }
  strncpy(s->subprotocol, subprotocol, sizeof(s->subprotocol));

  if(header == NULL) {
    strncpy(s->header, "", sizeof(s->header));
  } else {
    strncpy(s->header, header, sizeof(s->header));
  }

  if(port == 0) {
    s->port = 80;
  } else {
    s->port = port;
  }
  return 1;
}
/*---------------------------------------------------------------------------*/
int
websocket_http_client_get(struct websocket_http_client_state *s)
{
  uip_ip4addr_t ip4addr;
  uip_ip6addr_t ip6addr;
  uip_ip6addr_t *addr;
  uint16_t port;

  PRINTF("websocket_http_client_get: connecting to %s with file %s subprotocol %s header %s\n",
         s->host, s->file, s->subprotocol, s->header);


  s->state = STATE_WAITING_FOR_HEADER;

  if(tcp_socket_register(&s->s, s,
                         s->inputbuf, sizeof(s->inputbuf),
                         s->outputbuf, sizeof(s->outputbuf),
                         input, event) < 0) {
    return -1;
  }

  port = s->port;
  if(s->proxy_port != 0) {
    /* The proxy address should be an IPv6 address. */
    uip_ipaddr_copy(&ip6addr, &s->proxy_addr);
    port = s->proxy_port;
  } else if(uiplib_ip6addrconv(s->host, &ip6addr) == 0) {
    /* First check if the host is an IP address. */
    if(uiplib_ip4addrconv(s->host, &ip4addr) != 0) {
      ip64_addr_4to6(&ip4addr, &ip6addr);
    } else {
      /* Try to lookup the hostname. If it fails, we initiate a hostname
         lookup. */
      if(resolv_lookup(s->host, &addr) != RESOLV_STATUS_CACHED) {
        return -1;
      }
      return tcp_socket_connect(&s->s, addr, s->port);
    }
  }
  return tcp_socket_connect(&s->s, &ip6addr, port);
}
/*---------------------------------------------------------------------------*/
int
websocket_http_client_send(struct websocket_http_client_state *s,
                           const uint8_t *data,
                           uint16_t datalen)
{
  if(s->state == STATE_STEADY_STATE) {
    return tcp_socket_send(&s->s, data, datalen);
  }
  return -1;
}
/*---------------------------------------------------------------------------*/
int
websocket_http_client_sendbuflen(struct websocket_http_client_state *s)
{
  return tcp_socket_max_sendlen(&s->s);
}
/*---------------------------------------------------------------------------*/
void
websocket_http_client_close(struct websocket_http_client_state *s)
{
  tcp_socket_close(&s->s);
}
/*---------------------------------------------------------------------------*/
const char *
websocket_http_client_hostname(struct websocket_http_client_state *s)
{
  return s->host;
}
/*---------------------------------------------------------------------------*/
void
websocket_http_client_init(struct websocket_http_client_state *s)
{
  uip_create_unspecified(&s->proxy_addr);
  s->proxy_port = 0;
}
/*---------------------------------------------------------------------------*/
void
websocket_http_client_set_proxy(struct websocket_http_client_state *s,
                                const uip_ipaddr_t *addr, uint16_t port)
{
  uip_ipaddr_copy(&s->proxy_addr, addr);
  s->proxy_port = port;
}
/*---------------------------------------------------------------------------*/
int
websocket_http_client_queuelen(struct websocket_http_client_state *s)
{
  return tcp_socket_queuelen(&s->s);
}
/*---------------------------------------------------------------------------*/