// GenericList.cpp: Define o ponto de entrada para a aplicação de console.
//

#include "stdafx.h"

typedef struct Item {
	Item *ref;
	void *val;
} Item;

// Stack

typedef struct Stack {
	Item *last;
	int len;
} Stack;

Stack* newStack() {
	Stack *ptr = (Stack*)malloc(sizeof(Stack));
	ptr->last = NULL;
	ptr->len = 0;
	return ptr;
}

//Push pointer to stack
void stackPush(Stack *stack, void *item) {
	Item *ptr = (Item*)malloc(sizeof(Item));
	ptr->ref = stack->last;
	ptr->val = item;
	stack->last = ptr;
	stack->len++;
}

//Push pointer VALUE to stack
void stackPush(Stack *stack, void *item, int typeLen) {
	void *val = malloc(typeLen);
	memcpy(val, item, typeLen); //Why is it on string.h?
	stackPush(stack, val);
}

void* stackPop(Stack *stack) {
	if(stack->len == 0)
		return NULL;

	Item *item = stack->last;
	stack->last = item->ref;
	stack->len--;

	void *ptr = item->val;
	free(item);
	return ptr;
}

// Queue

typedef struct Queue {
	Item *first;
	Item *last;
	int len;
} Queue;

Queue* newQueue() {
	Queue *ptr = (Queue*)malloc(sizeof(Queue));
	ptr->first = NULL;
	ptr->last = NULL;
	ptr->len = 0;
	return ptr;
}

void enqueue(Queue *queue, void *item) {
	Item *ptr = (Item*)malloc(sizeof(Item));

	ptr->val = item;
	ptr->ref = NULL;

	if(queue->len == 0)
		queue->first = ptr;
	else
		queue->last->ref = ptr;

	queue->last = ptr;

	queue->len++;
}

void enqueue(Queue *queue, void *item, int typeLen) {
	void *val = malloc(typeLen);
	memcpy(val, item, typeLen);
	enqueue(queue, val);
}

void* dequeue(Queue *queue) {
	if(queue->len == 0)
		return NULL;

	Item *item = queue->first;

	queue->first = item->ref;
	queue->len--;

	void *ptr = item->val;
	free(item);
	return ptr;
}

int main() {
	int x;

	Stack *stack = newStack();
	x = 10;
	stackPush(stack, &x, sizeof(int));
	x = 12;
	stackPush(stack, &x, sizeof(int));
	x = 14;
	stackPush(stack, &x, sizeof(int));
	x = 16;
	stackPush(stack, &x, sizeof(int));

	printf("Stack test: %d %d %d %d\n", *(int*)stackPop(stack), *(int*)stackPop(stack), *(int*)stackPop(stack), *(int*)stackPop(stack));

	Queue *queue = newQueue();
	x = 99;
	enqueue(queue, &x, sizeof(int));
	x = 88;
	enqueue(queue, &x, sizeof(int));
	x = 77;
	enqueue(queue, &x, sizeof(int));
	x = 66;
	enqueue(queue, &x, sizeof(int));

	printf("Queue test: %d %d %d %d\n", *(int*)dequeue(queue), *(int*)dequeue(queue), *(int*)dequeue(queue), *(int*)dequeue(queue));
    return 0;
}