// Stack in C++ language

#include <iostream>
using namespace std;

#include "Person.hpp"                     // access Person class

class Stack {
  private:                                // list all privates
    const static int EMPTY_TOS = -1;      // constant TOS
    const static int STACK_SIZE = 100;    // constant array dimension
 
    int top;                              // current top, hidden in Stack
    Person *stack[STACK_SIZE];            // stack array, hidden in Stack

  public:                                 // list all public prototypes
    Stack();                              // constructor
    void push(Person*);                   // push a Person onto Stack
    Person* pop();                        // pop a Person from the Stack
    int isEmpty();                        // is it empty?
    int isFull();                         // is it full?
};

Stack::Stack() {                          // constructor implementation, init top
  top = EMPTY_TOS;
}

void Stack::push(Person* p) {             // push implementation
  if (!isFull())                          // here is the code is similar to C
    stack[++top] = p;
} 

Person* Stack::pop() {                    // pop implementation
  if (!isEmpty())
    return stack[top--];
  return NULL;
}

int Stack::isEmpty() {                    // isEmpty implementation
  return top == EMPTY_TOS;
}

int Stack::isFull() {                     // isFull implementation
  return top == STACK_SIZE-1;
}

int main(int argc, char *argv[]){
  Stack* s = new Stack();                 // construct a Stack
  s->push(new Person("Name 1",10));       // push 3 Persons onto stack
  s->push(new Person("Name 2",20));       // note: C did push(s,p) rather than s->push(p)
  s->push(new Person("Name 3",30));

  while (!s->isEmpty())                   // empty the Stack
    cout << (s->pop())->toString() << endl; // display contents

}