#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>

int * removeSpace(char* str) {

    char *out = str;
    char *put = str;

    for(; *str != '\0'; ++str)
    {
        if(*str != ' ')
        *put++ = *str;
    }
    *put = '\0';

  return out;
}

int string_length(char *string)
{
   int length = 0;

   while(*string)
   {
      length++;
      string++;
   }

   return length;
}

void reverses(char* reverse){
   int length, c;
   char *begin, *end, temp;

   length = string_length(reverse);

   begin = reverse;
   end = reverse;

   for ( c = 0 ; c < ( length - 1 ) ; c++ )
       end++;

   for ( c = 0 ; c < length/2 ; c++ )
   {
      temp = *end;
      *end = *begin;
      *begin = temp;

      begin++;
      end--;
   }
}

void lower_string(char* str) {
   int c = 0;

   while (str[c] != '\0') {
      if (str[c] >= 'A' && str[c] <= 'Z') {
         str[c] = str[c] + 32;
      }
      c++;
   }
}

void copy_string(char *target, char *source)
{
   while(*source)
   {
      *target = *source;
      source++;
      target++;
   }
   *target = '\0';
}

int compare_string(char *first, char *second)
{
   while(*first==*second)
   {
      if ( *first == '\0' || *second == '\0' )
         break;

      first++;
      second++;
   }
   if( *first == '\0' && *second == '\0' )
      return 0;
   else
      return -1;
}

int checkForPalindrom(char* string){

    int check, length;
    char *reverse;
    lower_string(string);
    length = string_length(string);
    reverse = (char*)malloc(length+1);

    copy_string(reverse,string);
    reverses(reverse);
    removeSpace(string);

    check = compare_string(string, reverse);

    free(reverse);

    if(check == 0)
        return 1;
    else
        return 0;

}

int main(void)
{
        char palindrom[100];
        bool quit = false;
        int result;
        char answer;
        while(!quit){



        printf("Skriv in en mening: ");
        //scanf(" %c")
        //scanf(" %[^\n]%*s", palindrom);
        gets(palindrom);

        result = checkForPalindrom(palindrom);


        if ( result == 1 )
            printf("\"%s\" is a palindrome string.\n", palindrom);
        else
            printf("\"%s\" is not a palindrome string.\n", palindrom);

        memset(palindrom, 0, 10);

        printf("\nWould you like to start over? (j/n): ");
        scanf("%s", &answer);

        if(answer == 'j')
            continue;
        else if(answer == 'n'){
            quit = true;
        }



        }


        return 0;
}