/** \file helpers.cpp
 *
 * Implementation of some auxiliary functions for memory dis-/allocation and so on
 */


#include "helpers.hpp"
#include "memoryusageobserver.hpp"

/********************************************** helpful functions *********************************/


/** Asks for a double value and checks input
 * \param *text question
 */
double ask_value(const char *text)
{
  double test = 0.1439851348959832147598734598273456723948652983045928346598365;
  do {
    cout << Verbose(0) << text;
    cin >> test;
  } while (test == 0.1439851348959832147598734598273456723948652983045928346598365);
  return test;
};

/** Output of a debug message to stderr.
 * \param *P Problem at hand, points to ParallelSimulationData#me
 * \param output output string
 */
#ifdef HAVE_DEBUG
void debug_in(const char *output, const char *file, const int line) {
  if (output) fprintf(stderr,"DEBUG: in %s at line %i: %s\n", file, line, output);
}
#else
void debug_in(const char *output, const char *file, const int line) {}  // print nothing
#endif

/** modulo operator for doubles.
 * \param *b pointer to double
 * \param lower_bound lower bound
 * \param upper_bound upper bound
 */
void bound(double *b, double lower_bound, double upper_bound)
{
  double step = (upper_bound - lower_bound);
  while (*b >= upper_bound)
    *b -= step;
  while (*b < lower_bound)
    *b += step;
};

/** Flips two doubles.
 * \param *x pointer to first double
 * \param *y pointer to second double
 */
void flip(double *x, double *y)
{
  double tmp;
  tmp = *x;
  *x = *y;
  *y = tmp;
};

/** Returns the power of \a n with respect to \a base.
 * \param base basis
 * \param n power
 * \return \f$base^n\f$
 */
int pot(int base, int n)
{
  int res = 1;
  int j;
  for (j=n;j--;)
    res *= base;
  return res;
};

/** Returns a string with \a i prefixed with 0s to match order of total number of molecules in digits.
 * \param FragmentNumber total number of fragments to determine necessary number of digits
 * \param digits number to create with 0 prefixed
 * \return allocated(!) char array with number in digits, ten base.
 */
char *FixedDigitNumber(const int FragmentNumber, const int digits)
{
  char *returnstring;
  int number = FragmentNumber;
  int order = 0;
  while (number != 0) { // determine number of digits needed
    number = (int)floor(((double)number / 10.));
    order++;
    //cout << "Number is " << number << ", order is " << order << "." << endl;
  }
  // allocate string
  returnstring = Malloc<char>(order + 2, "FixedDigitNumber: *returnstring");
  // terminate  and fill string array from end backward
  returnstring[order] = '\0';
  number = digits;
  for (int i=order;i--;) {
    returnstring[i] = '0' + (char)(number % 10);
    number = (int)floor(((double)number / 10.));
  }
  //cout << returnstring << endl;
  return returnstring;
};

/** Tests whether a given string contains a valid number or not.
 * \param *string
 * \return true - is a number, false - is not a valid number
 */
bool IsValidNumber( const char *string)
{
  int ptr = 0;
  if ((string[ptr] == '.') || (string[ptr] == '-')) // number may be negative or start with dot
    ptr++;
  if ((string[ptr] >= '0') && (string[ptr] <= '9'))
    return true;
  return false;
};

/**
 * Allocates a memory range using malloc().
 * Prints the provided error message in case of a failure.
 *
 * \param number of memory slices of type X to allocate
 * \param failure message which is printed if the allocation fails
 * \return pointer to the allocated memory range, will be NULL if a failure occurred
 */
template <> char* Malloc<char>(size_t size, const char* output)
{
  char* buffer = NULL;
  buffer = (char*) malloc(sizeof(char) * (size + 1));
  for (size_t i = size; i--;)
    buffer[i] = (i % 2 == 0) ? 'p': 'c';
  buffer[size] = '\0';

  if (buffer != NULL) {
    MemoryUsageObserver::getInstance()->addMemory(buffer, size);
  } else {
    cout << Verbose(0) << "Malloc for datatype " << typeid(char).name()
      << " failed - pointer is NULL: " << output << endl;
  }

  return buffer;
};