#include "SWindows.h"					// set up for windows
#include "IOTools.h"					// tools for safe I/O

// so far the Table can consist only of Records. It is possible
// to modify Table so that it takes any kind of class for its elements.
// Such a parametrized Table is done with  templates , which are the
// right and the only way to create a container like Table . 

struct Record {
   string name;
   int    value;
   Record()  { cout << "Creating a record\n"; }
   ~Record() { cout << "Destroying a record\n"; }
};

class Table {                // this is a SELF-EXPANDING table of records
private: 
   int capacity;
   int idx;
   Record * table;  
   Table( const Table & );   // no one can copy our objects:
   		  	     // no  void foo( Table t ); -- this needs to 
                             // call the copy contructor, which is hereby 
                             // made private, no  Table a =b;  no  Table a(b); 
   
   void operator=( const Table & ); // no one can assign to our objects:
                                    // no  a = b;
public:
   Table ( int init_capacity = 2 ); // initially, the table will be able 
                                    // to hold just two entries 
   ~Table ();
  
   void Add( const string & n, int value );
   int  Find( const string & n );
   
   // overloaded subsript operator, 
   //   two versions for const and non-const objects
   Record& operator[] (int index );
   Record  operator[] const (int index );
   void Print();
};   // end of Table definition  
   



Table::Table( int init_capacity ) : capacity( init_capacity ), idx(0) {
   cout << "Creating a table... Capacity is " << capacity << endl;
   table = new Record [ init_capacity ];  //calls Record() that many times
} 

Table::~Table(){ delete[ ] table; } // must ecplicitly "delete" anything 
                                    //   allocated with "new"

// returning a reference to a table record enables assignment to table
//  entries

Record& Table::operator[] (int index ){  
  if( index >= idx || idx < 0 ) {
    cerr << "Invalid index in Table::operator[]. Aborting program.\n";
    exit(-1);
  }  
  return table[index];  
}

// this variant is for objects passed as const reference that cannot be
// changed (in particular, cannot stand on the LHS of an assignment)

Record Table::operator[] const (int index ){ 
  if( index >= idx || idx < 0 ) {
    cerr << "Invalid index in Table::operator[] const. Aborting program.\n";
    exit(-1);
  }  
  return table[index];  
}


void Table::Add( const string& n, int r ){
  // currently we have "idx" entries  
  // if any unoccupied records remain from the previous allocation,
  // simple take the record number "idx"
  // If not: reallocate the memory array in which the values are stored
  
  if( idx == capacity ){
    // allocate new memory
    Record * new_table = new Record[ capacity*2 ];
    // copy old table over
    for( int i=0; i < capacity; i++ ) new_table[i] = table[i];
    
    delete[ ] table;   // delete old
    table = new_table; // pointer assignment, nothing get copied in
                       // the memory, but table is now pointing at a
                       // different (larger) chunk of memory    
    capacity *= 2;
    
    cout << "Reallocated memory... Capacity is now " << capacity << endl;
  }
  // slot "idx" is the next free slot; we know that it is free. Fill it now.
  table[ idx ].name  = n;
  table[ idx ].value = r;  
  idx++;
}  

void Table::Print(){ 
  for(int i=0; i<idx; i++)
     cout << i << " : " << table[i].name << " --> " << table[i].value << endl;
     
     // This should be  cout << table[i] << endl; -- 
     // Record must be smart enough to print itself.
     // this can be done by overloading  <<  for Record
     
  cout << idx << " entries total\n";
}    

// write your own function Find, to find a value by the title, 
// or signal error if the name is not in the tabble

void main()
{
    BigConsole();   	// open text and drawing windows
	
    Table movies;
    
    string s = "";
    int r;
    while(true){  // continue the loop until we break 
      cout << "Enter a title ('bye' to finish) : ";
      getline( cin, s );
      if( s == "bye" ) break;
      cout << "Enter its value: ";
      cin >> r;	
      movies.Add( s, r );
    }   
      
    cout << "We now have:\n";
    movies.Print();
   
    bool b;
   
    cout << "\nTesting []. Invalid index forces exit. \n" << endl;
   
    // input record numbers and print out and then modify its contents.

    PressReturn("Done!");
}