#include <stdlib.h>
#include <stdio.h>
#include <time.h>
#include <string.h>
#include "numbers.h"
#include "bintree.h"

//TODO: getDuplicate und createNumbers implementieren
/*  *   * Erzeugen eines Arrays mit der vom Nutzer eingegebenen Anzahl an Zufallszahlen.
  * Sicherstellen, dass beim Befüllen keine Duplikate entstehen.
  * Duplizieren eines zufälligen Eintrags im Array.
  * in `getDuplicate()`: Sortieren des Arrays und Erkennen der doppelten Zahl durch Vergleich benachbarter Elemente. */
 int compareInt(const void *arg1, const void *arg2) {
  int a = *(const int *)arg1;
  int b = *(const int *)arg2;
  return a - b;
}
// Returns len random numbers between 1 and 2x len in random order which are all different, except for two entries.
// Returns NULL on errors. Use your implementation of the binary search tree to check for possible duplicates while
// creating random numbers.
unsigned int *createNumbers(unsigned int len)
{
  unsigned int *numbers = malloc(sizeof(int)*len);
  unsigned int *arrayNoDup = malloc(sizeof(int)*len);
  unsigned int dupNumber;
  int dupLocation;
  if(!numbers){
    return NULL;
  }
  TreeNode *tree = NULL;
  int isDuplicate = 0;
  int gespeichert = 0;

  srand(time(NULL));
  while(gespeichert <len-1){
    arrayNoDup[gespeichert] = 1 + rand()%(2*len);
    tree = addToTree(tree,&arrayNoDup[gespeichert],sizeof(int),compareInt,&isDuplicate);
    if(!isDuplicate){
      gespeichert++;
    }
  }
  dupNumber = arrayNoDup[rand()%(len-1)];
  dupLocation = rand()%len;
  for(int i=0;i<len;i++){
    if(i<dupLocation){
      numbers[i]=arrayNoDup[i];
    }else if(i==dupLocation){
      numbers[i] = dupNumber;
    }else{
      numbers[i]=arrayNoDup[i-1];
    }

  }

  return numbers;
}

// Returns only the only number in numbers which is present twice. Returns zero on errors.
unsigned int getDuplicate(const unsigned int numbers[], unsigned int len)
{
  TreeNode *tree = NULL;
  int isduplicate=0;
  for(int i=0;i<len;i++){
    tree = addToTree(tree,&numbers[i],sizeof(numbers[0]),compareInt,&isduplicate);
    if(isduplicate){
      return numbers[i];
    }
  }
  return 0;
}