// ----------------------------------------------------------------------------- 
//  DataPack class:  an array plus its management information.
//  Implementation file for all DataPack programs.                  datapack.cpp
//  Created by Alice Fischer on Mon August 23, 2009
// ----------------------------------------------------------------------------- 
#include "datapack.hpp"

// --------------------------------------------------------------------- 
// Doubles the allocation size of the DataPack.
void DataPack::grow() {
    max *= 2;
    BT* newStore = new BT[max];
    for (int k = 0; k < n; ++k)
        newStore[k] = store[k];
    delete[] store;
    store = newStore;
}

// ---------------------------------------------------------------------
//  Read (from user) name of input file and open it.  
//  Read up to max items from input stream and store in array. 
void DataPack::readData() {
    char filename[80]; // For name of input file
    cout << "Enter name of data file: ";
    cin.getline(filename, 80);
    ifstream infile(filename);
    if (!infile)
        fatal("    Error: couldn't open input %s\n", filename);

    BT item;
    for (;;) {
        infile >> item;
        if (!infile.good())
            break; // Quit for bad data or for end of file.
        add(item); // Only good items are inserted
    }
}

// --------------------------------------------------------------------- 
//  Print the data from the array. 
void DataPack::printData(ostream& out) const {
    for (int k = 0; k < n; ++k) {
        out << store[k] << "\n";
    }
}

// --------------------------------------------------------------------- 
//  Sort data in the data pack.  The < and <= operators must be defined for BT.  
//
void DataPack::sortData() {
    BT* const end = store + n; // Off-board sentinel.
    BT* pass; // First unsorted item; begin pass here.
    BT newcomer; // Data value being inserted.
    BT* hole; // Array slot containing no data.

    for (pass = &store[1]; pass < end; ++pass) {
        // Pick up next item and insert into sorted portion of array.
        newcomer = *pass;
        for (hole = pass; hole > store; --hole) {
            if (*(hole - 1) <= newcomer)
                break; // Insertion slot is found.
            *hole = *(hole - 1); // Move item 1 slot rightward.
        }
        *hole = newcomer;
    }
}