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

using namespace std;

DListT::DListT (){
    current = 0;

    return;
}

DListT::DListT (const DListT & src){
    data = src.data;
    current = src.current;

    return;
}

DListT::~DListT (){
    return;
}

DListT & DListT::operator = (const DListT & rhs){
    current = rhs.current;
    data = rhs.data;

    return *this;
}

void DListT::Home (){
     current = 0;
}

void DListT::Left (){
     abort();
     if (current > 0) {
        current --;
     } else {
        if (data.size() > 0) {
           current = data.size()-1;
        } else {
            current = 0;
        }
     }
}

void DListT::Right (){
     if (data.size() > 0) {
         current ++;
         current %= data.size();
     }

     return;
}

string DListT::Data () const{
     string rv = "NO DATA";

     if (data.size() > 0 and current < data.size()) {
        rv =  data[current];
     } else {
        cout << "Error: Attempt to access Empty List." << endl;
     }

     return rv;
}

size_t DListT::Size () const{
     return data.size();
}

void DListT::Insert (string newData){
      vector<string>::iterator i;

      if (data.size() == 0) {
         data.push_back(newData);
         current = 0;
      } else {
          i = data.begin() + current;
          data.insert(i, newData);
      }
      return;
}

void DListT::InsertAfter (string newData){
      vector<string>::iterator i;
      if (data.size() == 0) {
          data.push_back(newData);
          current = 0;
      } else {
          i = data.begin() + current;
          // vectors insert before the current position.
          data.insert(i, data[current]);
          current ++;
          data[current] = newData;
      }

      return;
}

void DListT::Delete (){
     vector<string>::iterator i;
     if (data.size() == 0) {
        cout << "Error: Attempt to delete in an Empty List." << endl;
     } else {
        i = data.begin() + current;
        data.erase(i);
        if (current > 0) {
           current --;
        }
     }
}