/***************************************************************************
          ofx_preproc.cpp
                             -------------------
    copyright            : (C) 2002 by Benoit Gr�oir
    email                : benoitg@coeus.ca
***************************************************************************/
/**@file
 * \brief Preprocessing of the OFX files before parsing
 *
 Implements the pre-treatement of the OFX file prior to parsing:  OFX header striping, OFX proprietary tags and SGML comment striping, locating the appropriate DTD.
*/
/***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/
#include "../config.h"
#include <iostream>
#include <fstream>
#include <cstdlib>
#include <stdio.h>
#include <sstream>
#include <string>
#include "ParserEventGeneratorKit.h"
#include "libofx.h"
#include "messages.hh"
#include "ofx_sgml.hh"
#include "ofc_sgml.hh"
#include "ofx_preproc.hh"
#include "ofx_utilities.hh"
#ifdef HAVE_ICONV
#include <iconv.h>
#endif

#ifdef __WIN32__
# define DIRSEP "\\"
#else
# define DIRSEP "/"
#endif

#ifdef __WIN32__
# include "win32.hh"
# include <windows.h> // for GetModuleFileName()
# undef ERROR
# undef DELETE
#endif

#define LIBOFX_DEFAULT_INPUT_ENCODING "CP1252"
#define LIBOFX_DEFAULT_OUTPUT_ENCODING "UTF-8"

using namespace std;
/**
   \brief The number of different paths to search for DTDs.
*/
#ifdef MAKEFILE_DTD_PATH
const int DTD_SEARCH_PATH_NUM = 4;
#else
const int DTD_SEARCH_PATH_NUM = 3;
#endif

/**
   \brief The list of paths to search for the DTDs.
*/
const char *DTD_SEARCH_PATH[DTD_SEARCH_PATH_NUM] =
{
#ifdef MAKEFILE_DTD_PATH
  MAKEFILE_DTD_PATH ,
#endif
  "/usr/local/share/libofx/dtd",
  "/usr/share/libofx/dtd",
  "~"
};

/** @brief File pre-processing of OFX AND for OFC files
*
* Takes care of comment striping, dtd locating, etc.
*/
int ofx_proc_file(LibofxContextPtr ctx, const char * p_filename)
{
  LibofxContext *libofx_context;
  bool ofx_start = false;
  bool ofx_end = false;
  bool file_is_xml = false;

  ifstream input_file;
  ofstream tmp_file;
  char *filenames[3];
  char tmp_filename[256];
  int tmp_file_fd;
#ifdef HAVE_ICONV
  iconv_t conversion_descriptor;
#endif
  libofx_context = (LibofxContext*)ctx;

  if (p_filename != NULL && strcmp(p_filename, "") != 0)
  {
    message_out(DEBUG, string("ofx_proc_file():Opening file: ") + p_filename);

    input_file.open(p_filename);
    if (!input_file)
    {
      message_out(ERROR, "ofx_proc_file():Unable to open the input file " + string(p_filename));
    }

    mkTempFileName("libofxtmpXXXXXX", tmp_filename, sizeof(tmp_filename));

    message_out(DEBUG, "ofx_proc_file(): Creating temp file: " + string(tmp_filename));
#ifdef __WIN32__
    tmp_file_fd = mkstemp_win32(tmp_filename);
#else
    tmp_file_fd = mkstemp(tmp_filename);
#endif
    if (tmp_file_fd)
    {
      tmp_file.open(tmp_filename);
      if (!tmp_file)
      {
        message_out(ERROR, "ofx_proc_file():Unable to open the created temp file " + string(tmp_filename));
        return -1;
      }
    }
    else
    {
      message_out(ERROR, "ofx_proc_file():Unable to create a temp file at " + string(tmp_filename));
      return -1;
    }

    if (input_file && tmp_file)
    {
      int header_separator_idx;
      string header_name;
      string header_value;
      string ofx_encoding;
      string ofx_charset;
      do
      {
        stringbuf buffer;
        string s_buffer;
        input_file.get(buffer, '\n');
        //cout<< "got: \"" << buffer<<"\"\n";
        s_buffer = buffer.str();

        // Watch out: If input_file is in eof(), any subsequent read or
        // peek() will fail and we must exit this loop.
        if (!input_file.eof())
        {
            //cout<<"input_file.gcount(): "<<input_file.gcount()<< " s_buffer.size=" << s_buffer.size()<<" sizeof(buffer): "<<sizeof(buffer) << " peek=\"" << int(input_file.peek()) << "\"" <<endl;
            if (input_file.fail()) // If no characters were extracted above, the failbit is set.
            {
                // No characters extracted means that we've reached the newline
                // delimiter (because we already checked for EOF). We will check
                // for and remove that newline in the next if-clause, but must
                // remove the failbit so that peek() will work again.
                input_file.clear();
            }

            // Is the next character really the newline?
            if (input_file.peek() == '\n')
            {
                // Yes. Then discard that newline character from the stream
                input_file.get();
            }
        }

        if (ofx_start == false && (s_buffer.find("<?xml") != string::npos))
        {
          message_out(DEBUG, "ofx_proc_file(): File is an actual XML file, iconv conversion will be skipped.");
          file_is_xml = true;
        }

        int ofx_start_idx;
        if (ofx_start == false)
        {
          if (
              (libofx_context->currentFileType() == OFX &&
               ((ofx_start_idx = s_buffer.find("<OFX>")) != string::npos ||
                (ofx_start_idx = s_buffer.find("<ofx>")) != string::npos))
              ||
              (libofx_context->currentFileType() == OFC &&
                  ((ofx_start_idx = s_buffer.find("<OFC>")) != string::npos ||
                   (ofx_start_idx = s_buffer.find("<ofc>")) != string::npos))
             )
          {
            ofx_start = true;
            if (file_is_xml == false)
            {
                s_buffer.erase(0, ofx_start_idx); //Fix for really broken files that don't have a newline after the header.
            }
            message_out(DEBUG, "ofx_proc_file():<OFX> or <OFC> has been found");

            if (file_is_xml == true)
            {
                static char sp_charset_fixed[] = "SP_CHARSET_FIXED=1";
                if (putenv(sp_charset_fixed) != 0)
                {
                    message_out(ERROR, "ofx_proc_file(): putenv failed");
                }
                /* Normally the following would be "xml".
                * Unfortunately, opensp's generic api will garble UTF-8 if this is
                * set to xml.  So we set any single byte encoding to avoid messing
                * up UTF-8.  Unfortunately this means that non-UTF-8 files will not
                * get properly translated.  We'd need to manually detect the
                * encoding in the XML header and convert the xml with iconv like we
                * do for SGML to work around the problem.  Most unfortunate. */
                static char sp_encoding[] = "SP_ENCODING=ms-dos";
                if (putenv(sp_encoding) != 0)
                {
                    message_out(ERROR, "ofx_proc_file(): putenv failed");
                }
            }
            else
            {
                static char sp_charset_fixed[] = "SP_CHARSET_FIXED=1";
                if (putenv(sp_charset_fixed) != 0)
                {
                    message_out(ERROR, "ofx_proc_file(): putenv failed");
                }
                static char sp_encoding[] = "SP_ENCODING=ms-dos"; //Any single byte encoding will do, we don't want opensp messing up UTF-8;
                if (putenv(sp_encoding) != 0)
                {
                    message_out(ERROR, "ofx_proc_file(): putenv failed");
                }
#ifdef HAVE_ICONV
                string fromcode;
                string tocode;
                if (ofx_encoding.compare("USASCII") == 0)
                {
                    if (ofx_charset.compare("ISO-8859-1") == 0 || ofx_charset.compare("8859-1") == 0)
                    {
                        //Only "ISO-8859-1" is actually a legal value, but since the banks follows the spec SO well...
                        fromcode = "ISO-8859-1";
                    }
                    else if (ofx_charset.compare("1252") == 0 || ofx_charset.compare("CP1252") == 0)
                    {
                        //Only "1252" is actually a legal value, but since the banks follows the spec SO well...
                        fromcode = "CP1252";
                    }
                    else if (ofx_charset.compare("NONE") == 0)
                    {
                        fromcode = LIBOFX_DEFAULT_INPUT_ENCODING;
                    }
                    else
                    {
                        fromcode = LIBOFX_DEFAULT_INPUT_ENCODING;
                    }
                }
                else if (ofx_encoding.compare("UTF-8") == 0 || ofx_encoding.compare("UNICODE") == 0)
                {
                    //While "UNICODE" isn't a legal value, some cyrilic files do specify it as such...
                    fromcode = "UTF-8";
                }
                else
                {
                    fromcode = LIBOFX_DEFAULT_INPUT_ENCODING;
                }
                tocode = LIBOFX_DEFAULT_OUTPUT_ENCODING;
                message_out(DEBUG, "ofx_proc_file(): Setting up iconv for fromcode: " + fromcode + ", tocode: " + tocode);
                conversion_descriptor = iconv_open (tocode.c_str(), fromcode.c_str());
#endif
            }
          }
          else
          {
            //We are still in the headers
            if ((header_separator_idx = s_buffer.find(':')) != string::npos)
            {
                //Header processing
                header_name.assign(s_buffer.substr(0, header_separator_idx));
                header_value.assign(s_buffer.substr(header_separator_idx + 1));
                while ( header_value[header_value.length() -1 ] == '\n' ||
                        header_value[header_value.length() -1 ] == '\r' )
                header_value.erase(header_value.length() - 1);
                message_out(DEBUG, "ofx_proc_file():Header: " + header_name + " with value: " + header_value + " has been found");
                if (header_name.compare("ENCODING") == 0)
                {
                    ofx_encoding.assign(header_value);
                }
                if (header_name.compare("CHARSET") == 0)
                {
                    ofx_charset.assign(header_value);
                }
            }
          }
        }

        if (file_is_xml == true || (ofx_start == true && ofx_end == false))
        {
          if (ofx_start == true)
          {
            /* The above test won't help us if the <OFX> tag is on the same line
             * as the xml header, but as opensp can't be used to parse it anyway
             * this isn't a great loss for now.
             */
            s_buffer = sanitize_proprietary_tags(s_buffer);
            if (s_buffer.empty())
                continue;
          }
          //cout<< s_buffer<<"\n";
          if (file_is_xml == false)
          {
#ifdef HAVE_ICONV
            size_t inbytesleft = s_buffer.size();
            size_t outbytesleft = inbytesleft * 2 - 1;
            char * iconv_buffer = (char*) malloc (inbytesleft * 2);
            memset(iconv_buffer, 0, inbytesleft * 2);
#if defined(__sun) || defined(__NetBSD__)
            const char * inchar = (const char *)s_buffer.c_str();
#else
            char * inchar = (char *)s_buffer.c_str();
#endif
            char * outchar = iconv_buffer;
            int iconv_retval = iconv (conversion_descriptor,
                                      &inchar, &inbytesleft,
                                      &outchar, &outbytesleft);
            if (iconv_retval == -1)
            {
              message_out(ERROR, "ofx_proc_file(): Iconv conversion error");
            }
            // All validly converted bytes will be copied to the
            // original buffer
            s_buffer = std::string(iconv_buffer, outchar - iconv_buffer);
            free (iconv_buffer);
#endif
          }
          //cout << s_buffer << "\n";
          tmp_file << s_buffer << endl;
        }

        if (ofx_start == true &&
            (
              (libofx_context->currentFileType() == OFX &&
               ((ofx_start_idx = s_buffer.find("</OFX>")) != string::npos ||
                (ofx_start_idx = s_buffer.find("</ofx>")) != string::npos))
              || (libofx_context->currentFileType() == OFC &&
                  ((ofx_start_idx = s_buffer.find("</OFC>")) != string::npos ||
                   (ofx_start_idx = s_buffer.find("</ofc>")) != string::npos))
            )
           )
        {
          ofx_end = true;
          message_out(DEBUG, "ofx_proc_file():</OFX> or </OFC>  has been found");
        }

      }
      while (!input_file.eof() && !input_file.bad());
    }
    input_file.close();
    tmp_file.close();
#ifdef HAVE_ICONV
    if (file_is_xml == false)
    {
      iconv_close(conversion_descriptor);
    }
#endif
    char filename_openspdtd[255];
    char filename_dtd[255];
    char filename_ofx[255];
    strncpy(filename_openspdtd, find_dtd(ctx, OPENSPDCL_FILENAME).c_str(), 255); //The opensp sgml dtd file
    if (libofx_context->currentFileType() == OFX)
    {
      strncpy(filename_dtd, find_dtd(ctx, OFX160DTD_FILENAME).c_str(), 255); //The ofx dtd file
    }
    else if (libofx_context->currentFileType() == OFC)
    {
      strncpy(filename_dtd, find_dtd(ctx, OFCDTD_FILENAME).c_str(), 255); //The ofc dtd file
    }
    else
    {
      message_out(ERROR, string("ofx_proc_file(): Error unknown file format for the OFX parser"));
    }

    if ((string)filename_dtd != "" && (string)filename_openspdtd != "")
    {
      strncpy(filename_ofx, tmp_filename, 255); //The processed ofx file
      filenames[0] = filename_openspdtd;
      filenames[1] = filename_dtd;
      filenames[2] = filename_ofx;
      if (libofx_context->currentFileType() == OFX)
      {
        ofx_proc_sgml(libofx_context, 3, filenames);
      }
      else if (libofx_context->currentFileType() == OFC)
      {
        ofc_proc_sgml(libofx_context, 3, filenames);
      }
      else
      {
        message_out(ERROR, string("ofx_proc_file(): Error unknown file format for the OFX parser"));
      }
      if (remove(tmp_filename) != 0)
      {
        message_out(ERROR, "ofx_proc_file(): Error deleting temporary file " + string(tmp_filename));
      }
    }
    else
    {
      message_out(ERROR, "ofx_proc_file(): FATAL: Missing DTD, aborting");
    }
  }
  else
  {
    message_out(ERROR, "ofx_proc_file():No input file specified");
  }
  return 0;
}

/* Searches input string for a tag starting from pos.
 * If found will return the tag_name and pos will be set to the string position of the closing '>'
 * If the tag doesn't have a closing '>', pos will be set to string::npos.
 */
static string find_tag_open (string& input_string, size_t& pos)
{
    size_t start_idx = input_string.find ('<', pos);

    if (start_idx == string::npos)
    {
        pos = string::npos;
        return string();
    }

    size_t end_idx = input_string.find ('>', start_idx + 1);
    if (end_idx != string::npos)
        pos = end_idx + 1;
    end_idx = end_idx - (start_idx + 1);
    return input_string.substr(start_idx + 1, end_idx);
}

/* Searches input string for a closing tag matching tag_name starting from pos.
 * If found will pos will be set to the position right after of the closing '>'
 * If no matching closing tag is found pos will be set to the start of the next tag
 * found.
 */
static void find_tag_close (string& input_string, string& tag_name, size_t& pos)
{
    size_t start_idx = input_string.find ("</" + tag_name + ">", pos);

    if (start_idx == string::npos)
    {
        string new_tag_name = find_tag_open (input_string, pos);
        if (!new_tag_name.empty())
        {
            // find_tag_open returns the *end* of an opening tag, but in this
            // case we want its start, so we need to rewind a bit..
            pos = pos - new_tag_name.length() - 2;
        }
    }
    else
    {
        pos = std::min(input_string.length(), start_idx + tag_name.length() + 3);
    }
    return;
}


/**
   This function will strip all the OFX proprietary tags and SGML comments from the SGML string passed to it
   Note this function assumes in case a proprietary tag comes in an open and closing pair,
   they both appear on the same line (and hence are part of the same input_string passed to this function).
   So an ofx file with a single line like this <proprietary>abc</proprietary> will properly sanitized
   But an ofx file where this is split on multiple lines will not:
   <proprietary>
     abc
   </proprietary>
*/

string sanitize_proprietary_tags(string input_string)
{
  size_t last_known_good_pos = 0;
  size_t find_pos = last_known_good_pos;
  string tag_name = find_tag_open(input_string, find_pos);
  while (!tag_name.empty())
  {
    // Determine whether the current tag is proprietary.
    if ((tag_name.find('.') != string::npos) ||   // tag has a . in the name
       (tag_name == "CATEGORY"))                  // Chase bank started setting these in 2017
    {
        find_tag_close (input_string, tag_name, find_pos);
        size_t tag_size = find_pos - last_known_good_pos;
        string prop_tag = input_string.substr(last_known_good_pos, tag_size);
        message_out(INFO, "sanitize_proprietary_tags() removed: " + prop_tag);
        input_string.erase(last_known_good_pos, tag_size);
        find_pos = last_known_good_pos;
    }
    else
    {
        last_known_good_pos = find_pos;
    }
    tag_name.clear();
    if (last_known_good_pos != string::npos)
        tag_name = find_tag_open(input_string, find_pos);
  }
  return input_string;
}


#ifdef __WIN32__
static std::string get_dtd_installation_directory()
{
  // Partial implementation of
  // http://developer.gnome.org/doc/API/2.0/glib/glib-Windows-Compatibility-Functions.html#g-win32-get-package-installation-directory
  char ch_fn[MAX_PATH], *p;
  std::string str_fn;

  if (!GetModuleFileName(NULL, ch_fn, MAX_PATH)) return "";

  if ((p = strrchr(ch_fn, '\\')) != NULL)
    * p = '\0';

  p = strrchr(ch_fn, '\\');
  if (p && (_stricmp(p + 1, "bin") == 0 ||
            _stricmp(p + 1, "lib") == 0))
    *p = '\0';

  str_fn = ch_fn;
  str_fn += "\\share\\libofx\\dtd";

  return str_fn;
}
#endif


/**
   This function will try to find a DTD matching the requested_version and return the full path of the DTD found (or an empty string if unsuccessful)
   *
   Please note that currently the function will ALWAYS look for version 160, since OpenSP can't parse the 201 DTD correctly

   It will look, in (order)

   1- The environment variable OFX_DTD_PATH (if present)
   2- On windows only, a relative path specified by get_dtd_installation_directory()
   3- The path specified by the makefile in MAKEFILE_DTD_PATH, thru LIBOFX_DTD_DIR in configure (if present)
   4- Any hardcoded paths in DTD_SEARCH_PATH
*/
std::string find_dtd(LibofxContextPtr ctx, const std::string& dtd_filename)
{
  string dtd_path_filename;
  char *env_dtd_path;

  dtd_path_filename = reinterpret_cast<const LibofxContext*>(ctx)->dtdDir();
  if (!dtd_path_filename.empty())
  {
    dtd_path_filename.append(dtd_filename);
    ifstream dtd_file(dtd_path_filename.c_str());
    if (dtd_file)
    {
      message_out(STATUS, "find_dtd():DTD found: " + dtd_path_filename);
      return dtd_path_filename;
    }
  }

#ifdef __WIN32__
  dtd_path_filename = get_dtd_installation_directory();
  if (!dtd_path_filename.empty())
  {
    dtd_path_filename.append(DIRSEP);
    dtd_path_filename.append(dtd_filename);
    ifstream dtd_file(dtd_path_filename.c_str());
    if (dtd_file)
    {
      message_out(STATUS, "find_dtd():DTD found: " + dtd_path_filename);
      return dtd_path_filename;
    }
  }
#endif
  /* Search in environement variable OFX_DTD_PATH */
  env_dtd_path = getenv("OFX_DTD_PATH");
  if (env_dtd_path)
  {
    dtd_path_filename.append(env_dtd_path);
    dtd_path_filename.append(DIRSEP);
    dtd_path_filename.append(dtd_filename);
    ifstream dtd_file(dtd_path_filename.c_str());
    if (!dtd_file)
    {
      message_out(STATUS, "find_dtd():OFX_DTD_PATH env variable was was present, but unable to open the file " + dtd_path_filename);
    }
    else
    {
      message_out(STATUS, "find_dtd():DTD found: " + dtd_path_filename);
      return dtd_path_filename;
    }
  }

  for (int i = 0; i < DTD_SEARCH_PATH_NUM; i++)
  {
    dtd_path_filename = DTD_SEARCH_PATH[i];
    dtd_path_filename.append(DIRSEP);
    dtd_path_filename.append(dtd_filename);
    ifstream dtd_file(dtd_path_filename.c_str());
    if (!dtd_file)
    {
      message_out(DEBUG, "find_dtd():Unable to open the file " + dtd_path_filename);
    }
    else
    {
      message_out(STATUS, "find_dtd():DTD found: " + dtd_path_filename);
      return dtd_path_filename;
    }
  }

  /* Last resort, look in source tree relative path (useful for development) */
  dtd_path_filename = "";
  dtd_path_filename.append("..");
  dtd_path_filename.append(DIRSEP);
  dtd_path_filename.append("dtd");
  dtd_path_filename.append(DIRSEP);
  dtd_path_filename.append(dtd_filename);
  ifstream dtd_file(dtd_path_filename.c_str());
  if (!dtd_file)
  {
    message_out(DEBUG, "find_dtd(): Unable to open the file " + dtd_path_filename + ", most likely we are not in the source tree.");
  }
  else
  {
    message_out(STATUS, "find_dtd():DTD found: " + dtd_path_filename);
    return dtd_path_filename;
  }


  message_out(ERROR, "find_dtd():Unable to find the DTD named " + dtd_filename);
  return "";
}