import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Arrays;
import com.opencsv.CSVReader;
import java.net.URISyntaxException;
import java.util.*;
import javax.swing.SpinnerNumberModel;

public class AirbnbDataLoader {

    private HashMap<String, Integer> houseNumbers = new HashMap<String, Integer>();
    private ArrayList<AirbnbListing> listings;
    private int from;
    private int to;

    public AirbnbDataLoader(int fromValue, int toValue)
    {
        fillMap();
        listings = load();
        from = fromValue;
        to = toValue;

    }

    /**
     * Return an ArrayList containing the rows in the AirBnB London data set csv file.
     */
    public ArrayList<AirbnbListing> load() {
        System.out.print("Begin loading Airbnb london dataset...");
        listings = new ArrayList<AirbnbListing>();
        try{
            URL url = getClass().getResource("airbnb-london.csv");
            CSVReader reader = new CSVReader(new FileReader(new File(url.toURI()).getAbsolutePath()));
            String [] line;
            //skip the first row (column headers)
            reader.readNext();
            while ((line = reader.readNext()) != null) {
                String id = line[0];
                String name = line[1];
                String host_id = line[2];
                String host_name = line[3];
                String neighbourhood = line[4];
                double latitude = convertDouble(line[5]);
                double longitude = convertDouble(line[6]);
                String room_type = line[7];
                int price = convertInt(line[8]);
                int minimumNights = convertInt(line[9]);
                int numberOfReviews = convertInt(line[10]);
                String lastReview = line[11];
                double reviewsPerMonth = convertDouble(line[12]);
                int calculatedHostListingsCount = convertInt(line[13]);
                int availability365 = convertInt(line[14]);

                AirbnbListing listing = new AirbnbListing(id, name, host_id,
                        host_name, neighbourhood, latitude, longitude, room_type,
                        price, minimumNights, numberOfReviews, lastReview,
                        reviewsPerMonth, calculatedHostListingsCount, availability365
                    );
                listings.add(listing);
            }
        } catch(IOException | URISyntaxException e){
            System.out.println("Failure! Something went wrong");
            e.printStackTrace();
        }
        System.out.println("Success! Number of loaded records: " + listings.size());
        return listings;
    }

    /**
     *
     * @param doubleString the string to be converted to Double type
     * @return the Double value of the string, or -1.0 if the string is
     * either empty or just whitespace
     */
    private Double convertDouble(String doubleString){
        if(doubleString != null && !doubleString.trim().equals("")){
            return Double.parseDouble(doubleString);
        }
        return -1.0;
    }

    /**
     *
     * @param intString the string to be converted to Integer type
     * @return the Integer value of the string, or -1 if the string is
     * either empty or just whitespace
     */
    private Integer convertInt(String intString){
        if(intString != null && !intString.trim().equals("")){
            return Integer.parseInt(intString);
        }
        return -1;
    }

    private void fillMap()
    {
        houseNumbers.put("Kingston upon Thames",0);
        houseNumbers.put("Croydon",0);
        houseNumbers.put("Bromley",0);
        houseNumbers.put("Hounslow",0);
        houseNumbers.put("Ealing",0);
        houseNumbers.put("Havering",0);
        houseNumbers.put("Hillingdon",0);
        houseNumbers.put("Harrow",0);
        houseNumbers.put("Brent",0);
        houseNumbers.put("Barnet",0);
        houseNumbers.put("Enfield",0);
        houseNumbers.put("Waltham Forest",0);
        houseNumbers.put("Redbridge",0);
        houseNumbers.put("Sutton",0);
        houseNumbers.put("Lambeth",0);
        houseNumbers.put("Southwark",0);
        houseNumbers.put("Redbridge",0);
        houseNumbers.put("Lewisham",0);
        houseNumbers.put("Bexley",0);
        houseNumbers.put("Richmond upon Thames",0);
        houseNumbers.put("Merton",0);
        houseNumbers.put("Wandsworth",0);
        houseNumbers.put("Hammersmith and Fulham",0);
        houseNumbers.put("Kensington and Chelsea",0);
        houseNumbers.put("City of London",0);
        houseNumbers.put("Westminster",0);
        houseNumbers.put("Tower Hamlets",0);
        houseNumbers.put("Greenwich",0);
        houseNumbers.put("Barking and Dagenham",0);
        houseNumbers.put("Newham",0);
        houseNumbers.put("Haringey",0);
        houseNumbers.put("Hackney",0);
        houseNumbers.put("Islington",0);
        houseNumbers.put("Camden",0);
    }

    public HashMap<String, Integer> getHouseNumbersHashMap()
    {

        for(AirbnbListing listing: listings)
        {
            if(listing.getPrice()>=from && listing.getPrice()<=to)
            {
                String neighbourhood= listing.getNeighbourhood();
                int value= houseNumbers.get(neighbourhood);
                houseNumbers.put(listing.getNeighbourhood(), value+1);
            }

        }

        return houseNumbers;
    }
}