/**
 * Assignment 8 // Problem 2
 * For UPEI Computer Science 1910 Fall 2018
 *
 * @author Josh Theriault
 * @version 11/25/2018
 */

import java.util.Scanner;
import java.util.Arrays;
import java.io.File;
import java.io.FileNotFoundException;

public class Problem2
{
    //-------------------------------------------------------------------
    // Reads data from "flightTimes.csv" file into arrays
    //-------------------------------------------------------------------
    private static void loadData(String[] codes, String[][] times) throws FileNotFoundException
    {
        Scanner in = new Scanner(new File("flightTimes.csv"));
        //First line is flight codes, read them into String[] codes
        if (in.hasNextLine())
        {
            Scanner codesIn = new Scanner(in.nextLine());
            codesIn.useDelimiter(",");
            int i = 0;
            while (codesIn.hasNext())
            {
                String code = codesIn.next();
                codes[i] = code;
                i++;
            }
            codesIn.close();
        }
        //Next lines are flight times, read them into String[][] times
        int i = 0;
        while (in.hasNextLine())
        {
            Scanner timesIn = new Scanner(in.nextLine());
            timesIn.useDelimiter(",");
            int j = 0;
            while (timesIn.hasNext())
            {
                String time = timesIn.next();
                times[i][j] = time;
                j++;
            }
            timesIn.close();
            i++;
        }
    }

    //-------------------------------------------------------------------
    // Handles user flight time searches using a sentinel loop
    //-------------------------------------------------------------------
    private static void doSearches(String[] codes, String[][] times)
    {
        Scanner in = new Scanner(System.in);

        //Get initial input
        System.out.print("From: ");
        String fromAirport = in.nextLine();
        System.out.print("To: ");
        String toAirport = in.nextLine();

        //Sentinal loop for additional input
        while (!fromAirport.equals("DONE") && !toAirport.equals("DONE"))
        {
            int fromAirportIndex = indexOf(codes, fromAirport);
            int toAirportIndex = indexOf(codes, toAirport);

            if (fromAirportIndex >= 0)
            {
                if (toAirportIndex >= 0)
                {
                    String flyingTime = times[toAirportIndex][fromAirportIndex];
                    System.out.printf("Flying time is: %s%n", flyingTime);
                }
                else
                {
                    System.out.println("ERROR: Unknown airport destination " + toAirport);
                }
            }
            else
            {
                System.out.println("ERROR: Unknown airport destination " + fromAirport);
            }

            System.out.println();

            //Refetch input
            System.out.print("From: ");
            fromAirport = in.nextLine();
            if (fromAirport.equals("DONE"))
            {
                break;
            }
            System.out.print("To: ");
            toAirport = in.nextLine();
        }

        System.out.println("Happy travels!");
    }

    //-------------------------------------------------------------------
    // Finds the index of an airport code in the codes array
    //-------------------------------------------------------------------
    private static int indexOf(String[] codes, String code)
    {
        for (int i = 0; i < codes.length; i++)
        {
            if (code.equals(codes[i]))
            {
                return i;
            }
        }
        return -1; //-1 means the airport code was not found
    }

    public static void main(String[] args)
    {
        //create arrays, etc. here
        //call loadData and doSearches from here
        final int airports = 10;
        String[] flightCodes = new String[airports];
        String[][] flightTimes = new String[airports][airports];

        System.out.println("Flight time calculator");
        System.out.println("Enter airport codes as prompted.\n");

        try
        {
            loadData(flightCodes, flightTimes);
            doSearches(flightCodes, flightTimes);
        }
        catch (FileNotFoundException e)
        {
            System.out.println("ERROR: flightTimes.csv could not be opened");
        }
    }
}