#ifndef NUMBERTOSTRING_H
#define NUMBERTOSTRING_H

#include "JSONDebug.h"
#ifdef JSON_LESS_MEMORY
    #include "JSONMemory.h"
#endif
#include <cstdio>
#ifdef JSON_STRICT
    #include <cmath>
#endif
template <unsigned int GETLENSIZE>
struct getLenSize{
    char tmp[GETLENSIZE == 16];  // compile time assertion
    enum {GETLEN = 41};
};

template<>
struct getLenSize<1>{
    enum {GETLEN = 5};
};

template <>
struct getLenSize<2>{
    enum {GETLEN = 7};
};

template <>
struct getLenSize<4>{
    enum {GETLEN = 12};
};

template <>
struct getLenSize<8>{
    enum {GETLEN = 22};
};

static inline bool _floatsAreEqual(const json_number & one, const json_number & two) json_pure;
static inline bool _floatsAreEqual(const json_number & one, const json_number & two) json_nothrow {
    return (one > two) ? (one - two) < JSON_FLOAT_THRESHHOLD : (one - two) > -JSON_FLOAT_THRESHHOLD;
}

#ifdef JSON_LESS_MEMORY
    #define num_str_result s.ptr
#endif

class NumberToString {
public:
    template<typename T>
    static json_string _itoa(T val) json_nothrow {
	   #ifdef JSON_LESS_MEMORY
		  json_auto<json_char> s(getLenSize<sizeof(T)>::GETLEN);
	   #else
		  json_char num_str_result[getLenSize<sizeof(T)>::GETLEN];
	   #endif
	   num_str_result[getLenSize<sizeof(T)>::GETLEN - 1] = JSON_TEXT('\0'); //null terminator
	   json_char * runner = &num_str_result[getLenSize<sizeof(T)>::GETLEN - 2];
	   bool negative;

	   START_MEM_SCOPE
	   long value = (long)val;
	   //first thing, check if it's negative, if so, make it positive
	   if (value < 0){
		  value = -value;
		  negative = true;
	   } else {
		  negative = false;
	   }

	   //create the string
	   do {
		  *runner-- = (json_char)(value % 10) + JSON_TEXT('0');
	   } while(value /= 10);
	   END_MEM_SCOPE

	   //if it's negative, add the negation
	   if (negative){
		  *runner = JSON_TEXT('-');
		  return json_string(runner);
	   }
	   return json_string(runner + 1);
    }

    #ifndef JSON_LIBRARY
	   template<typename T>
	   static json_string _uitoa(T val) json_nothrow {
		  #ifdef JSON_LESS_MEMORY
			 json_auto<json_char> s(getLenSize<sizeof(T)>::GETLEN);
		  #else
			 json_char num_str_result[getLenSize<sizeof(T)>::GETLEN];
		  #endif
		  num_str_result[getLenSize<sizeof(T)>::GETLEN - 1] = JSON_TEXT('\0'); //null terminator
		  json_char * runner = &num_str_result[getLenSize<sizeof(T)>::GETLEN - 2];

		  //create the string
		  START_MEM_SCOPE
			 unsigned long value = (unsigned long)val;
			 do {
				*runner-- = (json_char)(value % 10) + JSON_TEXT('0');
			 } while(value /= 10);
		  END_MEM_SCOPE

		  return json_string(runner + 1);
	   }
    #endif

    #ifdef JSON_ISO_STRICT
	   #define EXTRA_LONG
	   #define FLOAT_STRING "%f"
	   #define LFLOAT_STRING L"%f"
    #else
	   #define EXTRA_LONG long
	   #define FLOAT_STRING "%Lf"
	   #define LFLOAT_STRING L"%Lf"
    #endif

    static json_string _ftoa(json_number value) json_nothrow {
	   #ifndef JSON_LIBRARY
		  if (json_unlikely(value > 0.0 && _floatsAreEqual(value, (json_number)((unsigned EXTRA_LONG long)value)))){
			 return _uitoa<unsigned EXTRA_LONG long>((unsigned EXTRA_LONG long)value);
		  } else
	   #endif
		  if (json_unlikely(_floatsAreEqual(value, (json_number)((long EXTRA_LONG)value)))){
			 return _itoa<long EXTRA_LONG>((long EXTRA_LONG)value);
		  }

	   #ifdef JSON_LESS_MEMORY
		  json_auto<json_char> s(64);
	   #else
		  json_char num_str_result[64];
	   #endif
	   #ifdef JSON_UNICODE
		  std::swprintf(num_str_result, 63, LFLOAT_STRING, (EXTRA_LONG double)value);
	   #else
		  //Thanks to Salvor Hardin for this Visual C++ fix
		  #ifdef _MSC_VER
			 _snprintf_s(num_str_result, 63, 63, FLOAT_STRING, (EXTRA_LONG double)value); //yes, 63 appears twice using _snprintf_s()
		  #else
			 std::snprintf(num_str_result, 63, FLOAT_STRING, (EXTRA_LONG double)value);
		  #endif
	   #endif
	   //strip the trailing zeros
	   for(json_char * pos = &num_str_result[0]; *pos; ++pos){
		  if (json_unlikely(*pos == '.')){  //only care about after the decimal
			 for(json_char * runner = pos + 1; *runner; ++runner){
				if (json_likely(*runner != JSON_TEXT('0'))) pos = runner + 1;  //have to go to the end 1.0001
			 }
			 *pos = JSON_TEXT('\0');
			 break;
		  }
	   }
	   return json_string(num_str_result);
    }

    #if defined(JSON_SAFE) || defined(JSON_DEBUG)
	   static bool isNumeric(const json_string & str) json_nothrow {
		  const json_char * p = str.c_str();
		  bool decimal = false;
		  bool scientific = false;

		  //first letter is weird
		  switch(*p){
			 case '\0':
				return false;
		  #ifndef JSON_STRICT
			 case '.':
				decimal = true;
				break;
			 case '+':
		  #endif
			 case '-':
			 case '1':
			 case '2':
			 case '3':
			 case '4':
			 case '5':
			 case '6':
			 case '7':
			 case '8':
			 case '9':
				break;
			 case '0':
				++p;
				switch(*p){
				    case '.':
					   decimal = true;
					   break;
				    case 'e':
				    case 'E':
					   scientific = true;
					   ++p;
					   switch(*p){
						  case '\0':
							 return false;
						  case '-':
						  case '+':
						  case '0':
						  case '1':
						  case '2':
						  case '3':
						  case '4':
						  case '5':
						  case '6':
						  case '7':
						  case '8':
						  case '9':
							 break;
						  default:
							 return false;
					   }
					   break;
				    #ifndef JSON_STRICT
					   case 'x':
						  return (str.find_first_not_of(JSON_TEXT("0123456789ABCDEFabcdef"), 2) == json_string::npos);
					   case '1':
					   case '2':
					   case '3':
					   case '4':
					   case '5':
					   case '6':
					   case '7':
						  return (str.find_first_not_of(JSON_TEXT("01234567"), 1) == json_string::npos);
				    #endif
				    case '\0':  //just 0
					   return true;
				    default:
					   return false;
				}
				break;
			 default:
				return false;
		  }
		  ++p;

		  //next digits
		  while (*p){
			 switch(*p){
				case '.':
				    if (json_unlikely(decimal)) return false; //multiple decimals
				    if (json_unlikely(scientific)) return false;
				    decimal = true;
				    break;
				case 'e':
				case 'E':
				    if (json_unlikely(scientific)) return false;
				    scientific = true;
				    ++p;
				    switch(*p){
					   case '\0':
						  return false;
					   case '-':
					   case '+':
					   case '0':
					   case '1':
					   case '2':
					   case '3':
					   case '4':
					   case '5':
					   case '6':
					   case '7':
					   case '8':
					   case '9':
						  break;
					   default:
						  return false;
				    }
				    break;
				case '0':
				case '1':
				case '2':
				case '3':
				case '4':
				case '5':
				case '6':
				case '7':
				case '8':
				case '9':
				    break;
				default:
				    return false;
			 }
			 ++p;
		  }
		  return true;
	   }
    #endif

    #ifdef JSON_STRICT
	   //much faster because no octal or hex support
	   json_number _atof (json_char * num){
		  json_number sign = (json_number)1.0;

		  //sign
		  if (*num==JSON_TEXT('-')){
			 sign = -1.0;
			 ++num;
		  }

		  //skip leading zeros
		  while (*num == JSON_TEXT('0')){
			 ++num;
		  }

		  // Number
		  json_number n = (json_number)0.0
		  if (json_likely(*num >= JSON_TEXT('1') && *num <= JSON_TEXT('9'))){
			 do {
				n = (n * 10.0) + (*num++ - JSON_TEXT('0'));
			 } while (*num >= JSON_TEXT('0') && *num <= JSON_TEXT('9'));
		  }

		  // Fractional part
		  json_number scale = (json_number)0.0;
		  if (*num==JSON_TEXT('.')) {
			 ++num;
			 do {
				n = (n * 10.0) + (*num++ - JSON_TEXT('0'));
				--scale;
			 } while (*num>=JSON_TEXT('0') && *num<=JSON_TEXT('9'));
		  }

		  // Exponent
		  int subscale = 0, signsubscale = 1;
		  if (json_unlikely(*num == JSON_TEXT('e') || *num == JSON_TEXT('E'))){
			 ++num;
			 switch(*num){
				case JSON_TEXT('+'):
				    ++num;
				    break;
				case JSON_TEXT('-'):
				    signsubscale = -1;
				    ++num;
				    break;
			 }
			 while (*num >= JSON_TEXT('0') && *num <= JSON_TEXT('9')){
				subscale=(subscale * 10) + (*num++ - JSON_TEXT('0'));
			 }
		  }

		  return sign * n * pow(10.0, scale + subscale * signsubscale);	// number = +/- number.fraction * 10^+/- exponent
	   }
    #endif
};

#endif