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

#include "phish_local_xml.h"
#include "phish.h"
#include "phish_util_ll.h"

#define BUF_SIZE 8192

static const char *protocol;
static const char *server;
static const char *path;
static char ip_addr[16];

/* used to determine whether copy the comments to url_data structure */
static int in_comments = 0;
static int change_comments = 0; /* whether or not to change the comments */
                                /* currently in the results object */


static void XMLCALL
startElem(phish_url_data_t *url_data, const char *el, const char **attr)
{
  int i;
  const char *element_server = NULL;
  const char *element_path = NULL;
  const char *element_ip = NULL;
  
  if (strcmp(el, "comments") == 0)
    in_comments = 1;

  /* set the element_[server|path|ip] strings.             */
  /* note that if the name of the attribute is at attr[i], */
  /* its value is at attr[i+1].                            */
  for (i = 0; attr[i]; i += 2) 
  {
    if (strcmp(attr[i], "protocol") == 0)
      continue;

    if ( (strcmp(attr[i], "server") == 0) )
    {
      element_server = attr[i+1];
      continue;
    }

    if ( (strcmp(attr[i], "path") == 0) )
    {
      element_path = attr[i+1];
      continue;
    }

    if ( (strcmp(attr[i], "ip") == 0) )
    {
      element_ip = attr[i+1];
      continue;
    }
  }

  /* check if server matches */
  if (element_server && strcmp(element_server, server) == 0)
  {
    url_data->server = 1;
  
    /* check if path matches too */
    if (element_path && strcmp(element_path, path) == 0)
    { 
      url_data->path = 1;
      change_comments = 1;
    }

    /* we don't want to change the comments if the current comments are */
    /* more specific (relate to server+path match).                     */
    if (url_data->path == 0)
      change_comments = 1;
  }

  /* check if ip matches */
  if (element_ip && strcmp(element_ip, ip_addr) == 0) 
  { 
    url_data->ip = 1;
  }
}

static void XMLCALL
endElem(phish_url_data_t *url_data, const char *el)
{
  if (strcmp(el, "comments") == 0)
    in_comments = 0;
  
  change_comments = 0; /* we're moving to the next element */
}

static void XMLCALL 
charHandler(phish_url_data_t *url_data, const XML_Char *s, int len)
{
  if (in_comments && change_comments)
  {
    char *newcomm; 
    int prevlen = url_data->comments_length;
    
    len += prevlen;
    
    newcomm = malloc(len+1);

    /* first copy the comment to continue parsing */
    strncpy(newcomm, url_data->comments, prevlen);
    /* copy the rest of the comment */
    strncpy(newcomm+prevlen, s, len-prevlen);
    newcomm[len] = '\0';

    free(url_data->comments); /* free old comments */
    url_data->comments = newcomm; /* set new comments */
    url_data->comments_length = len;
  }
}


phish_result_t phish_localxml_checkURL(const char *xml_file,
                                       phish_util_url_t *url,
                                       const char *ip,
                                       phish_url_data_t *results)
{
  char buf[BUF_SIZE];
  FILE *input_file;
  
  /* set up the parser and element handlers */
  XML_Parser p = XML_ParserCreate(NULL);
  if (!p)
    return PHISH_ERR_MEMORY;
  
  XML_SetElementHandler(p, (XML_StartElementHandler)startElem,
                        (XML_EndElementHandler)endElem);
  XML_SetCharacterDataHandler(p, (XML_CharacterDataHandler)charHandler);
  XML_SetUserData(p, results); /* handlers will fill the 'results' objects */
  
  protocol = url->protocol;
  server = url->host;
  path = url->path;
  strcpy(ip_addr, ip);
  
  input_file = fopen(xml_file, "r");
  if (!input_file)
    return PHISH_XML_READ_ERROR;

  /* one or more of these values will be to 1 if a match is found */
  results->server = 0;
  results->ip = 0;
  results->path = 0;
  
  /* search inside local XML file */
  while (1) 
  {
    int done;
    int len;

    len = fread(buf, 1, BUF_SIZE, input_file);
    if (ferror(input_file)) 
    {
      fclose(input_file);
      return PHISH_XML_READ_ERROR;
    }
    
    /* parse the content as long as there's no error and EOF isn't reached */
    done = feof(input_file);
    if (XML_Parse(p, buf, len, done) == XML_STATUS_ERROR)
    {
      fclose(input_file);
      return PHISH_XML_PARSE_ERROR;
    }

    if (done)
      break;
  }
  fclose(input_file);

  return PHISH_SUCCESS;
}