package visualiser.model;

import javafx.application.Platform;
import javafx.collections.ObservableList;
import javafx.scene.chart.LineChart;
import javafx.scene.chart.NumberAxis;
import javafx.scene.chart.XYChart;
import javafx.scene.paint.Color;

import java.util.List;


/**
 * Class to process and modify a sparkline display. This display keeps visual
 * track of {@link VisualiserBoat}s in a race and their current
 * placing position as they complete each {@link shared.model.Leg} by
 * passing a course {@link shared.model.Mark}. <br>
 * This sparkline is displayed using the
 * {@link visualiser.Controllers.RaceController}.
 */
public class Sparkline {

    /**
     * The race to observe.
     */
    private VisualiserRace race;

    /**
     * The boats to observe.
     */
    private ObservableList<VisualiserBoat> boats;

    /**
     * The number of legs in the race.
     * Used to correctly scale the linechart.
     */
    private Integer legNum;


    /**
     * The linchart to plot sparklines on.
     */
    private LineChart<Number, Number> sparklineChart;

    /**
     * The x axis of the sparkline chart.
     */
    private NumberAxis xAxis;

    /**
     * The y axis of the sparkline chart.
     */
    private NumberAxis yAxis;


    /**
     * Constructor to set up initial sparkline (LineChart) object
     * @param race The race to listen to.
     * @param sparklineChart JavaFX LineChart for the sparkline.
     */
    public Sparkline(VisualiserRace race, LineChart<Number,Number> sparklineChart) {
        this.race = race;
        this.boats = race.getBoats();
        this.legNum = race.getLegCount();

        this.sparklineChart = sparklineChart;
        this.yAxis = (NumberAxis) sparklineChart.getYAxis();
        this.xAxis = (NumberAxis) sparklineChart.getXAxis();

        createSparkline();

    }


    /**
     * Creates and sets initial display for Sparkline for race positions.
     * A data series for each boat in the race is added.
     * Position numbers are displayed.
     */
    private void createSparkline() {
        // NOTE: Y axis is in negatives to display correct positions

        //For each boat...
        for (VisualiserBoat boat : this.boats) {

            //Create data series for each boat.
            XYChart.Series<Number, Number> series = new XYChart.Series<>();


            //All boats start in "last" place.
            series.getData().add(new XYChart.Data<>(0, boats.size()));

            //Listen for changes in the boat's leg - we only update the graph when it changes leg.
            boat.legProperty().addListener(
                    (observable, oldValue, newValue) -> {

                        //Get the data to plot.
                        List<VisualiserBoat> boatOrder = race.getLegCompletionOrder().get(oldValue);
                        //Find boat position in list.
                        int boatPosition = boatOrder.indexOf(boat) + 1;

                        //Get leg number.
                        int legNumber = oldValue.getLegNumber() + 1;


                        //Create new data point for boat's position at the new leg.
                        XYChart.Data<Number, Number> dataPoint = new XYChart.Data<>(legNumber, boatPosition);

                        //Add to series.
                        Platform.runLater(() -> series.getData().add(dataPoint));


                    });


            //Add to chart.
            sparklineChart.getData().add(series);

            //Color using boat's color. We need to do this after adding the series to a chart, otherwise we get null pointer exceptions.
            series.getNode().setStyle("-fx-stroke: " + colourToHex(boat.getColor()) + ";");


        }

        sparklineChart.setCreateSymbols(false);

        //Set x axis details
        xAxis.setAutoRanging(false);
        xAxis.setTickMarkVisible(false);
        xAxis.setTickLabelsVisible(false);
        xAxis.setMinorTickVisible(false);
        xAxis.setLowerBound(0);
        xAxis.setUpperBound(legNum + 2);
        xAxis.setTickUnit(1);

        //Set y axis details
        yAxis.setLowerBound(boats.size());
        yAxis.setUpperBound(1);
        yAxis.setAutoRanging(false);
        yAxis.setLabel("Position in Race");
        yAxis.setTickUnit(-1);//Negative tick reverses the y axis.

        yAxis.setTickMarkVisible(true);
        yAxis.setTickLabelsVisible(true);
        yAxis.setTickMarkVisible(true);
        yAxis.setMinorTickVisible(true);
    }


    /**
     * Converts a color to a hex string, starting with a {@literal #} symbol.
     * @param color The color to convert.
     * @return Hex string of the color (e.g., {@literal "#11AB4C"}).
     */
    private static String colourToHex(Color color) {
        return String.format( "#%02X%02X%02X",
                (int)( color.getRed() * 255 ),
                (int)( color.getGreen() * 255 ),
                (int)( color.getBlue() * 255 ) );
    }

}