#include <stdlib.h>
#include "Item.h"
#define null(A) (key(st[A]) == key(NULLitem))

static int N, M;
static Item *st;

void STinit(int max)
{
      int i;
      N=0; M = 2*max;
      st = malloc(M*sizeof(Item));
      for(i = 0; i < M; i++) st[i] = NULLitem;
}

int STcount() { return N; }

void STinsert(Item item)
{
      Key v = key(item);
      int i = hash(v, M);
      while(!null(i))
            i = (i + 1) % M;
      st[i] = item; N++;
}

Item STsearch (Key v)
{
      int i = hash(v, M);
      while( !null(i))
            if(v == key(st[i]))
                  return st[i];
            else
                  i = (i + 1) % M;
      return NULLitem;
}

int hash( char *v, int M)
{
      int h, a = 31415, b = 27183;
      for(h = 0; *v != '\0'; v++, a = a*b % (M - 1))
            h = (a*h + *v) % M;
      return h;
}

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


static int N, M;

struct studentType
{
char name[20];
int age;
int id;
float gpa;
};

typedef struct studentType student;
student theStudent;
student nullStudent;

student *oaTable;
student *currentPos;

int hash(char *v, int W);
void hashTable(int max);
int count ();
void insert(student addStudent);
student search(student searchStudent);



/*
*******************Main Function*************************************************
*/


int main(int argc, char *argv[])
{
   int count, datasize;  
   FILE* fdata=NULL;
   FILE* fsearch=NULL;
   student studentArray[200];
   student studentNameArray[200];
  
   printf("Hello World");
   if(argc != 3)
   {
    printf ("Invalid number of arguments");
    printf("\n");    
    exit(0);
   }
  
   printf("Hello World4");
   hashTable(200);
  

   /*read file 1*/
   count = 0;
   fdata = fopen(argv[1], "r");

   if (fdata == NULL)
   {
    fprintf(stderr, "Can't open input file input!\n");
    printf("Error: file %s doesn't exist.\n", argv[2]);    
    exit(1);
   }
  
   printf("Hello World3");
  
   while (fscanf(fdata, "%s %d %d %f", theStudent.name, &theStudent.age,&theStudent.id,&theStudent.gpa) != EOF)
   {
    
        studentArray[count]=theStudent;
    printf("Hello World1");
    insert(theStudent);
    printf("Hello World2");

        count++;
        datasize = count;
   }
  
  /*
  printf("%d", datasize);
  printf("\n");
  */
  printf("%s", studentArray[125].name);
  printf("\n");
  
  
  /* Opens search file.*/
  fsearch=fopen(argv[2], "r");
  if(!fsearch)
  {
    fprintf(stderr, "Can't open input file input!\n");
    printf("Error: file %s doesn't exist.\n", argv[2]);
    exit(1);
  }
  count = 0;
  while (fscanf(fsearch, "%s", theStudent.name) != EOF)
   {
        studentNameArray[count]=theStudent;        
        count++;
        datasize = count;
   }
  
  
  /* Closes both files. */
  fclose(fdata);
  fclose(fsearch);    
  return 0;
}

/*
My hash function for strings
*/

int hash(char *v, int W)
{
    int h, a = 31415, b = 27183;
    for( h= 0; *v != '\0'; v++, a = a*b % (W - 1))
        h = (a*b + *v) % W;
    return h;
}


/*
This function builds by hash table.
*/

void hashTable(int max)
{    
    int i;
    N = 0;
    M = 2*max;    
    oaTable = malloc(M*sizeof(student));
    currentPos = oaTable;
    for(i = 0; i < M; i++)
    {
        *currentPos = nullStudent;
        currentPos++;
    }
    currentPos = oaTable;
}
/*
Keeps count of the number of entries I have in my table
*/
int count ()
{
    return N;
}
/*
Inserts a student struct into hash table.
*/
void insert(student addStudent)
{
    char *v = addStudent.name;
    int i = hash(v,M);
    printf("Hello World");
    while(oaTable[i].name != nullStudent.name)
        i = (i + 1) % M;
    oaTable[i] = addStudent;
    N++;
}
/*
This funciton searches for the entry.
*/
student search(student searchStudent)
{
    char *v = searchStudent.name;
    int i = hash(v, M);
    while(oaTable[i].name != nullStudent.name)
    {
        if(searchStudent.name == oaTable[i].name)
            return oaTable[i];
        else
            i = (i + 1 ) % M;
    }
    return nullStudent;
}