/* 
 * Copyright (c) 2011, 2013 Oracle and/or its affiliates. All rights reserved.
 *
 * 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; version 2 of the
 * License.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301  USA
 */


#include "base/sqlstring.h"


using namespace base;

const sqlstring sqlstring::null(sqlstring("NULL", 0));

sqlstring::sqlstring(const char* format_string, const sqlstringformat format)
: _format_string_left(format_string), _format(format)
{
  append(consume_until_next_escape());
}


sqlstring::sqlstring(const sqlstring &copy)
: _formatted(copy._formatted), _format_string_left(copy._format_string_left), _format(copy._format)
{
}

sqlstring::sqlstring()
: _format(0)
{
}

std::string sqlstring::consume_until_next_escape()
{
  std::string::size_type e = _format_string_left.length(), p = 0;
  while (p < e)
  {
    char ch = _format_string_left[p];
    if (ch == '?' || ch == '!')
      break;
    ++p;
  }
  if (p > 0)
  {
    std::string s = _format_string_left.substr(0, p);
    if (p < e)
      _format_string_left = _format_string_left.substr(p);
    else
      _format_string_left.clear();
    return s;
  }
  return "";
}


int sqlstring::next_escape()
{
  if (_format_string_left.empty())
    throw std::invalid_argument("Error formatting SQL query: more arguments than escapes"); 
  int c = _format_string_left[0];
  _format_string_left = _format_string_left.substr(1);
  return c;
}


sqlstring &sqlstring::append(const std::string &s)
{
  _formatted.append(s);
  return *this;
}


sqlstring::operator std::string () const
{
  return _formatted + _format_string_left;
}


bool sqlstring::done() const
{
  if (_format_string_left.empty())
    return true;
  return _format_string_left[0] != '!' && _format_string_left[0] != '?';
}

sqlstring &sqlstring::operator <<(const double v)
{
  int esc = next_escape();
  if (esc != '?')
    throw std::invalid_argument("Error formatting SQL query: invalid escape for numeric argument");

  append(strfmt("%f", v));
  append(consume_until_next_escape());

  return *this;
}

sqlstring &sqlstring::operator <<(const sqlstringformat format)
{
    _format = format;
    return *this;
}

sqlstring &sqlstring::operator <<(const std::string& v)
{
  int esc = next_escape();
  if (esc == '!')
  {
    if(v.empty())
    {
        throw std::invalid_argument("Error formatting SQL query: empty string given as argument for ! character");
    }

    std::string escaped = escape_backticks(v);
    if ((_format._flags & QuoteOnlyIfNeeded) != 0)
      append(base::quote_identifier_if_needed(escaped, '`'));
    else
      append(base::quote_identifier(escaped, '`'));
  } 
  else if (esc == '?')
  {
    if (_format._flags & UseAnsiQuotes)
      append("\"").append(escape_sql_string(v)).append("\"");
    else
      append("'").append(escape_sql_string(v)).append("'");
  }
  else // shouldn't happen
    throw std::invalid_argument("Error formatting SQL query: internal error, expected ? or ! escape got something else");
  append(consume_until_next_escape());

  return *this;
}


sqlstring &sqlstring::operator <<(const sqlstring& v)
{
  next_escape();

  append(v);
  append(consume_until_next_escape());

  return *this;
}



sqlstring &sqlstring::operator <<(const char* v)
{
  int esc = next_escape();

  if (esc == '!')
  {
    if (!v)
      throw std::invalid_argument("Error formatting SQL query: NULL value found for identifier");
    std::string quoted = escape_backticks(v);
    if (quoted == v && (_format._flags & QuoteOnlyIfNeeded))
      append(quoted);
    else
      append("`").append(quoted).append("`");
  } 
  else if (esc == '?')
  {
    if (v)
    {
      if (_format._flags & UseAnsiQuotes)
        append("\"").append(escape_sql_string(v)).append("\"");
      else
        append("'").append(escape_sql_string(v)).append("'");
    }
    else
      append("NULL");
  }
  else // shouldn't happen
    throw std::invalid_argument("Error formatting SQL query: internal error, expected ? or ! escape got something else");
  append(consume_until_next_escape());

  return *this;
}

