/*
 * Copyright (c) 2009, 2016 Jeffrey Armstrong
 * Copyright (c) 2001-2005, Adam Dunkels.
 * 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 uIP TCP/IP stack.
 *
 */

#include "httpd.h"
#include "uip.h"
#include "httpd-fs.h"
#include "http-str.h"

#include <string.h>
#include <time.h>

#define STATE_WAITING 0
#define STATE_OUTPUT  1

#define ISO_nl      0x0a
#define ISO_space   0x20
#define ISO_bang    0x21
#define ISO_percent 0x25
#define ISO_period  0x2e
#define ISO_slash   0x2f
#define ISO_colon   0x3a


static unsigned short generate_part_of_file(void *state)
{
  struct httpd_state *s = (struct httpd_state *)state;

  if(s->file.len > uip_mss()) {
    s->len = uip_mss();
  } else {
    s->len = s->file.len;
  }
  
  fread(uip_appdata,sizeof(char),s->len,s->file.fp);

  if(s->len >= s->file.len)
      fclose(s->file.fp);
  
  return s->len;
}

static PT_THREAD(send_file(struct httpd_state *s))
{
  PSOCK_BEGIN(&s->sout);
  
  do {
    PSOCK_GENERATOR_SEND(&s->sout, generate_part_of_file, s);
    s->file.len -= s->len;
  } while(s->file.len > 0);
      
  PSOCK_END(&s->sout);
}


static PT_THREAD(send_part_of_file(struct httpd_state *s))
{
  PSOCK_BEGIN(&s->sout);

  PSOCK_SEND(&s->sout, uip_appdata, s->len);
  
  PSOCK_END(&s->sout);
}

static PT_THREAD(send_headers(struct httpd_state *s, const char *statushdr))
{
  char *ptr;

  PSOCK_BEGIN(&s->sout);
  
  PSOCK_SEND_STR(&s->sout, statushdr);

  if(s->compressed)
    PSOCK_SEND_STR(&s->sout, http_content_encode);

  ptr = strrchr(s->filename, ISO_period);
  if(ptr == NULL) {
    PSOCK_SEND_STR(&s->sout, http_content_type_binary);
  } else if(strncmp(http_html, ptr, 5) == 0 ||
            strncmp(http_shtml, ptr, 6) == 0 ||
            strncmp(http_htm, ptr, 4) == 0 ||
            strncmp(http_hgz, ptr, 4) == 0) {
    PSOCK_SEND_STR(&s->sout, http_content_type_html);
  } else if(strncmp(http_css, ptr, 4) == 0 ||
            strncmp(http_cgz, ptr, 4) == 0) {
    PSOCK_SEND_STR(&s->sout, http_content_type_css);
  } else if(strncmp(http_png, ptr, 4) == 0) {
    PSOCK_SEND_STR(&s->sout, http_content_type_png);
  } else if(strncmp(http_gif, ptr, 4) == 0) {
    PSOCK_SEND_STR(&s->sout, http_content_type_gif);
  } else if(strncmp(http_jpg, ptr, 4) == 0) {
    PSOCK_SEND_STR(&s->sout, http_content_type_jpg);
  } else if(strncmp(http_rss, ptr, 4) == 0 ||
            strncmp(http_rgz, ptr, 4) == 0) {
    PSOCK_SEND_STR(&s->sout, http_content_type_rss);
  } else {
    PSOCK_SEND_STR(&s->sout, http_content_type_plain);
  }
  
  PSOCK_END(&s->sout);
}


static PT_THREAD(handle_output(struct httpd_state *s))
{
  char *ptr;
  time_t ltime;
  
  PT_BEGIN(&s->outputpt);

  printf("%s requested - ", s->filename);
  
  if(s->compressed == 1 && compressed_available(s->filename) == 1)
    compressed_name(s->filename);
  else
    s->compressed = 0;
  
  ltime = time(NULL);
  printf("using %s - %s", s->filename, ctime(&ltime));
 
  if(httpd_fs_open(s->filename, &s->file) < 0) {

    strcpy(s->filename, FILE_404);
    PT_WAIT_THREAD(&s->outputpt,
                   send_headers(s,
                   http_header_404));
                   
    if(httpd_fs_open(s->filename, &s->file))
        PT_WAIT_THREAD(&s->outputpt,
                       send_file(s));
    
  } else {
    PT_WAIT_THREAD(&s->outputpt,
                   send_headers(s,
                   http_header_200));
    /* ptr = strchr(s->filename, ISO_period); */
    PT_WAIT_THREAD(&s->outputpt, send_file(s));
  }
  
  PSOCK_CLOSE(&s->sout);
  PT_END(&s->outputpt);
}

static PT_THREAD(handle_input(struct httpd_state *s))
{
  int i;
  
  PSOCK_BEGIN(&s->sin);

  PSOCK_READTO(&s->sin, ISO_space);

  
  if(strncmp(s->inputbuf, http_get, 4) != 0) {
    PSOCK_CLOSE_EXIT(&s->sin);
  }
  PSOCK_READTO(&s->sin, ISO_space);

  if(s->inputbuf[0] != ISO_slash) {
    PSOCK_CLOSE_EXIT(&s->sin);
  }

  if(s->inputbuf[1] == ISO_space) {
    strncpy(s->filename, http_index_html, sizeof(s->filename));
  } else {
    s->inputbuf[PSOCK_DATALEN(&s->sin) - 1] = 0;
    strncpy(s->filename, &s->inputbuf[0], sizeof(s->filename));
  }

  /*  httpd_log_file(uip_conn->ripaddr, s->filename);*/
  s->compressed = 0;
  while(1) {
    PSOCK_READTO(&s->sin, ISO_nl);

    if(strncmp(s->inputbuf, http_referer, 8) == 0) {
      s->inputbuf[PSOCK_DATALEN(&s->sin) - 2] = 0;
      /*      httpd_log(&s->inputbuf[9]);*/
    } else if(strncmp(s->inputbuf, http_accept_encode, 17) == 0) {
      i = 17;
      while(s->inputbuf[i] != ISO_nl) {
        if(strncmp(&s->inputbuf[i], http_gzip, 4) == 0) {
          s->compressed = 1;
          break;
        }
        i++;
      } 
    } else if(PSOCK_DATALEN(&s->sin) < 3) {
      break;
    }
    
  }
  
  s->state = STATE_OUTPUT;
  PSOCK_END(&s->sin);
}

static void handle_connection(struct httpd_state *s)
{
  handle_input(s);
  if(s->state == STATE_OUTPUT) {
    handle_output(s);
  }
}

void httpd_appcall(void)
{
  struct httpd_state *s = (struct httpd_state *)&(uip_conn->appstate);

  if(uip_closed() || uip_aborted() || uip_timedout()) {
  } else if(uip_connected()) {
    PSOCK_INIT(&s->sin, s->inputbuf, sizeof(s->inputbuf) - 1);
    PSOCK_INIT(&s->sout, s->inputbuf, sizeof(s->inputbuf) - 1);
    PT_INIT(&s->outputpt);
    s->state = STATE_WAITING;
    /*    timer_set(&s->timer, CLOCK_SECOND * 100);*/
    s->timer = 0;
    handle_connection(s);
  } else if(s != NULL) {
    if(uip_poll()) {
      ++s->timer;
      if(s->timer >= 20) {
        uip_abort();
      }
    } else {
      s->timer = 0;
    }
    handle_connection(s);
  } else {
    uip_abort();
  }
}

void httpd_init(void)
{
  uip_listen(HTONS(80));
}