#include<iostream>
#include<string>
#include<stdlib.h>

#define HASHSIZE 1000

using namespace std;

class item {

	public:

	string data;
	item *nxt;
	int tablepos;

	void show();
};


class list {
	
	public:

	void find(string finddata);
	void add(string in_data);
	void delete_current();
	void display();
	list();
	~list();
	

	
	item *start[HASHSIZE];
	item *cursor; 
	
};

void item::show() {

	cout << "Data: " << data << endl;
	cout << "Next record at: " << nxt << endl;
	cout << "In table position: " << tablepos << endl;
}


//Constructor:  initialize the hash table linked lists.

list::list() {
	for(int i = 0; i <=HASHSIZE; i++)
		list::start[i] = NULL;
}

list::~list() {

	item *temp, *temp2;

	for(int i = 0; i <= HASHSIZE; i++) 
	{
		if(start[i] != NULL) 
		{
			temp = start[i];
			while(temp->nxt != NULL) 
			{
				temp2 = temp;
				temp = temp2->nxt;
				delete temp2;
			}
			delete temp;
			temp = NULL;
		}
	}

}



void list::add(string in_data) {

	int hash = 0;
	char hashchar;
	item *tempitem;
		
	for (int i = 0; i < in_data.length(); i++) 
	{
					//hashchar = in_data.at(i);
		cout << "Char: " << int(in_data.at(i)) << ", hash:";
		hash += int(in_data.at(i));
		cout << hash << endl;
	}
	
	hash = hash % HASHSIZE;		//Make the hash using sum and modulus.  Any good hack works here.
	
					// Now check hash location and add value to linked list there.

					//First check the slot.  If it's empty (NULL), then this item is the first link.

	if (start[hash]==NULL) 
	{
		start[hash] = new item;
		cursor = start[hash];
		cursor->data = in_data;
		cursor->nxt = NULL;
		cursor->tablepos = hash;
	}

					//Otherwise, it "attaches" to a previous, existing link.
	
	else 
	{
		cursor = start[hash];
		while(cursor->nxt != NULL) 
		{
			tempitem = cursor->nxt;
			cursor = tempitem;
		}

		tempitem = new item;
		tempitem->data = in_data;
		tempitem->nxt = NULL; 	//Create our item and populate it
		tempitem->tablepos = hash;
		cursor->nxt = tempitem;	//Set the previous item 'nxt' to link to our new item.
		cursor = tempitem;	//Set the new item as current (cursor points to current item)
	}	
}


void list::delete_current() {

	string answer;
	cout << "Deleting: " << endl;

	cursor->show();  		//Lets ask the Microsoft question here, just in case...

	cout << "Do you want to delete this record? (y/n)" << endl;
	cin >> answer;
	
	if(answer.length() == 0 || answer.at(0) != 'y') 
	{
		cout << "Action cancelled." << endl;
		return;
	}
	
					//At this point, the answer starts with a 'y', so...

	item *temp, *temp2;
	int table_cursor;
	
					//Is our pointer, "cursor", valid?

	if(cursor == NULL) 
	{
		cout << "Invalid position." << endl;
		return;
	}
	
	
	temp = cursor;
	table_cursor = cursor->tablepos;
	cursor = start[table_cursor];  	//Is this the first link in the slot?  If so, delete it and reset start[]
	if(temp == cursor) 
	{
		start[cursor->tablepos] = NULL;
		delete cursor;
		return;
	}

	//Scroll through the items to find the item before "temp" and have "cursor" point at that.

	while(cursor->nxt != temp) 
	{
		cursor = cursor->nxt;
	} 

	// Found previous.  At this point, cursor points to the "item" before temp.
	
	if(temp->nxt == NULL) 
	{ 			 //Is "temp" the last link? If so, cursor now becomes the last.
		cursor->nxt = NULL;
		delete temp;
		return;
	}

	// If we get here, the record to be deleted is in the "middle" of a list.  We link "cursor"
	// to the record past "temp" (temp->nxt) then kill temp.


	cursor->nxt = temp->nxt;
	delete temp;
	return;

}
		
		
		

int main(int argv, char *argc[]) {

	//Do some stuff.  Go crazy here.

	list hlist;
	string pass = "Test";
	hlist.add(pass);
	hlist.cursor->show();
	hlist.add(pass);
	hlist.cursor->show();

	hlist.delete_current();

}