//---------------------------------------------------------
// The purpose of this program is to test the list class
// implementation for Lab 05. This program reads a file
// containing double values and displays the number of
// values, the minimum, the maximum and the average.
//
// D. Searls
// Asbury College
// Jan 2008
//---------------------------------------------------------

#include <iostream>
#include <fstream>
#include <iomanip>
#include "Lab05_list.cpp"
using namespace std;

//---------------------------------------------------------
// readData
//
// Read a list of doubles from a file.
//
// Out Parameter: myList
//---------------------------------------------------------
void readData(list<double>& myList)
{
    string filename;
    ifstream infile;
    double x;
    
    cout << "Enter the name of the data file: ";
    cin >> filename;
    cout << endl;
    
    infile.open(filename.c_str());
    if (infile.fail())
    {
        cout << "Could not open the input file!" << endl;
        exit(0);
    }

    infile >> x;
    while (!infile.fail())
    {
        myList.push_front(x);
        infile >> x;
    }
}

//---------------------------------------------------------
// minimum
//
// Returns the minimum value in the list.
//
// In Parameter: myList
//---------------------------------------------------------
double minimum(list<double>& myList)
{
    double* minLowPos = myList.first();
    double min;
    double* itr;
    
    for(itr = myList.first(); itr != myList.end(); itr = myList.next())
    {
        if (*itr < *minLowPos)
        {
            minLowPos = itr;
        }
    }
    
    min = *minLowPos;
    
    return min;
}

//---------------------------------------------------------
// maximum
//
// Returns the maximum value in the list.
//
// In Parameter: myList
//---------------------------------------------------------
double maximum(list<double>& myList)
{
    double max = *(myList.first());
    double* itr;
    
    for(itr = myList.first(); itr != myList.end(); itr = myList.next())
    {
        if (*itr > max)
        {
            max = *itr;
        }
    }
    
    return max;
}

//---------------------------------------------------------
// mean
//
// Return a record containing the mean of the low
// temperatures and the mean of the high temperatures.
//
// In Parameter: myList
//---------------------------------------------------------
double mean(list<double>& myList)
{
    double sum;
    double* itr;    
    
    sum = 0.0;
    for(itr = myList.first(); itr != myList.end(); itr = myList.next())
    {
        sum = sum + *itr;
    }
    
    return sum/static_cast<double>(myList.size());
}

//---------------------------------------------------------
// displayResults
//
// Display the number of values, the mean, the minimum, and
// the maximum.
//
// In Parameters: n, mean, min, max
//---------------------------------------------------------
void displayResults(int n, double mean, double min, double max)
{
    cout << fixed << setprecision(1);
    cout << "   n:" << setw(3) << n << endl;
    cout << "Mean:" << setw(5) << mean << endl;
    cout << " Min:" << setw(5) << min << endl;
    cout << " Max:" << setw(5) << max << endl;
}

//---------------------------------------------------------
// displayList
//
// Display contents of list on one line.
//
// In parameter: myList
//---------------------------------------------------------
void displayList(list<double>& myList)
{
    double* itr;
    
    cout << fixed << setprecision(0);
    for(itr = myList.first(); itr != myList.end(); itr = myList.next())
    {
        cout << "  " << *itr;
    }
    cout << endl << endl;
}

//*********************************************************
//                   M A I N   D R I V E R
//*********************************************************

int main()
{
    list<double> myList;    // List of temperature records
    readData(myList);
    displayList(myList);
    displayResults(myList.size(), mean(myList),
                   minimum(myList), maximum(myList));
    cout << endl;
    
    // Create a copy of the list and then clear the orginal.
    
    list<double> copy(myList);
    myList.clear();
    cout << "Size of myList: " << myList.size() << " (0 EXPECTED)\n";
    cout << "First element in myList: ";
    if (myList.first() != myList.end())
    {
        cout << *(myList.first());
    }
    cout << "(blank EXPECTED)" << endl << endl;
    
    // Display the results for the copy.
    
    displayList(copy);
    displayResults(copy.size(), mean(copy),
                   minimum(copy), maximum(copy));
    cout << endl;
    
    // Remove first two elements and display the results.
    
    copy.pop_front();
    copy.pop_front();
    displayList(copy);
    
    // Clear list and try to remove first element
    
    copy.clear();
    copy.pop_front();
    cout << "Size of copy: " << copy.size() << " (0 EXPECTED)\n";
    cout << "First element in copy: ";
    if (copy.first() != copy.end())
    {
        cout << *(copy.first());
    }
    cout << "(blank EXPECTED)" << endl;
                   
    return 0;
}