#include <iostream>
#include "ListT.h"

using namespace std;

struct NodeT {
    int data;
    NodeT * next;
};

ListT::ListT(){
    head = nullptr;
    size = 0;

    return;
}


// assume dest is not a valid pointer
void CopyList(NodeT * & dest, NodeT * src) {

     NodeT * tmp = nullptr;
     NodeT * travler = nullptr;
     NodeT * follow = nullptr;

     dest = nullptr;

     for(travler = src; travler != nullptr; travler = travler->next) {
          tmp = new NodeT;
          tmp -> data = travler -> data;
          tmp -> next = nullptr;

          if (follow == nullptr) {
              follow = tmp;
              dest = tmp;
          } else {
              follow ->next = tmp;
              follow = tmp;
          }
     }

     return;
}

ListT::ListT(const ListT & rhs){
    // copy the static data 
    size = rhs.size;

    // copy the dynamic data
    CopyList(head, rhs.head);
   
    return;
}

void DeleteList(NodeT * head){
    NodeT * tmp;

    while (head != nullptr) {
        tmp = head;
        head=head->next;
        delete tmp;
    }

    return;
}

ListT::~ListT(){
    // delete the dynamic data in this instance.
    DeleteList(head);
    head = nullptr;

    return;
}

ListT & ListT::operator = (const ListT & rhs){
    // delete the dynamic data in this instance.
    DeleteList(head);
    head = nullptr;

    // copy the static data 
    size = rhs.size;
    // copy the dynamic data
    CopyList(head, rhs.head);

    return * this;
}

void ListT::Insert(int item){
    NodeT * tmp = nullptr;

    tmp = new NodeT;
    tmp->data = item;
    tmp->next = head;

    head = tmp;

    size ++;

    return;
}

void ListT::Delete(int item){
    NodeT * tmp = nullptr;
    NodeT * follow = nullptr;

    if (head != nullptr) {

         if (head->data == item) {
               tmp = head;
               head = head->next;
               delete tmp;
               size--;
         } else {
               follow = head;
               tmp = head->next;

               // find intem in the list (or get to the end)
               while(tmp!= nullptr and tmp->data != item) {
                   follow = tmp;
                   tmp=tmp->next;
               }

               if (tmp != nullptr) {
                  follow->next = tmp->next;
                  delete tmp;
                  size --;
               }
         }
    }

    return;
}

bool ListT::Find(int item) const{
    NodeT * tmp = nullptr;
    bool found = false;

    for(tmp = head; tmp != nullptr  and not found; tmp=tmp->next)  {
        if (tmp->data == item) {
           found = true;
        }
    }

    return found;
}

size_t ListT::Size(void) const{
    return size;
}

void ListT::PrintList(void) const{
    NodeT * tmp = nullptr;

    for(tmp = head; tmp != nullptr; tmp=tmp->next)  {
       cout << tmp->data << " " ;
    }
    return;
}