////////////////////////////////  list.h  ////////////////////////////////////
// Simple linked list, uses Node as linked list node

#ifndef LIST_H
#define LIST_H

#include "nodedata.h"
#include <iostream>
#include <fstream>
using namespace std;

//--------------------------  class List  ------------------------------------
// ADT List: finite, ordered collection of zero or more items.
//           The ordering is determined by operator< of NodeData class.
//          
// Assumptions:  
//    -- Control of <, printing, etc of NodeData information is in the 
//       NodeData class.  
//    -- There is no dummy head node, head points to first node.  
//       If empty, head is NULL.
//    -- The insert allocates memory for a Node, ptr to the data is passed in.
//
// Note this definition is not a complete class and is not fully documented.
//----------------------------------------------------------------------------
class List {
   friend ostream &operator<<(ostream&, const List&);

public:
   List();                                      // default constructor
   // ~List();                                  // destructor
   // List(const List&);                        // copy constructor
   bool insert(NodeData*);                      // insert one Node into list
   bool isEmpty() const;                        // is list empty?
   void buildList(ifstream&);                   // build a list from datafile
   void printBackwards() const;                 // print the list in reverse

   // needs many more member functions to become a complete ADT

private:
   struct Node {              // the node in a linked list
      NodeData* data;         // pointer to actual data, operations in NodeData
      Node* next;
   };

   Node* head;                                  // pointer to first node
   void printBackwardsHelper(Node*) const;      // actual backwards printer
};

#endif