content: /*
   * Copyright (c) 2019-2022 GeyserMC. http://geysermc.org
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   *
   * @author GeyserMC
   * @link https://github.com/GeyserMC/Geyser
   */
  
  package org.allaymc.server.gui;
  
  import lombok.Setter;
  
  import javax.swing.*;
  import java.awt.*;
  import java.io.Serial;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.List;
  
  /**
   * @author daoge_cmd
   */
  public final class GraphPanel extends JPanel {
  
      @Serial
      private static final long serialVersionUID = 1L;
  
      private static final int PADDING = 10;
      private static final int LABEL_PADDING = 25;
      private static final int POINT_WIDTH = 4;
      private static final int NUMBER_Y_DIVISIONS = 20;
  
      private static final Color TEXT_COLOR = Color.WHITE;
      private static final Color BACKGROUND_COLOR = new Color(40, 40, 40);
      private static final Color GRID_COLOR = Color.GRAY;
  
      private static final Stroke GRAPH_STROKE = new BasicStroke(2f);
  
      private static final int MAX_SCORE_THRESHOLD = 100;
      private static final int MIN_SCORE_THRESHOLD = 0;
  
      private final Color lineColor = new Color(44, 102, 230, 200);
      private final Color pointColor = new Color(44, 102, 230, 200);
      private final List<Integer> values = new ArrayList<>();
      private int minScore = MIN_SCORE_THRESHOLD;
      private int maxScore = MAX_SCORE_THRESHOLD;
      @Setter
      private boolean variableExtreme = true;
      @Setter
      private String xLabel = "";
  
      public GraphPanel() {
          setPreferredSize(new Dimension(700 - (PADDING * 2), 700 - (PADDING * 2)));
      }
  
      public void setValues(Collection<Integer> newValues) {
          values.clear();
          addValues(newValues);
          calculateExtremum();
      }
  
      public void addValues(Collection<Integer> newValues) {
          values.addAll(newValues);
          updateUI();
      }
  
      @Override
      protected void paintComponent(Graphics graphics) {
          super.paintComponent(graphics);
          if (!(graphics instanceof final Graphics2D g)) {
              graphics.drawString("Graphics is not Graphics2D, unable to render", 0, 0);
              return;
          }
  
          g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
  
          var length = values.size();
          var width = getWidth();
          var height = getHeight();
          var maxScore = this.maxScore;
          var minScore = this.minScore;
          var scoreRange = maxScore - minScore;
  
          // draw background
          g.setColor(BACKGROUND_COLOR);
          g.fillRect(
                  PADDING + LABEL_PADDING,
                  PADDING,
                  width - (2 * PADDING) - LABEL_PADDING,
                  height - 2 * PADDING - LABEL_PADDING
          );
          g.setColor(Color.BLACK);
  
          var fontMetrics = g.getFontMetrics();
          var fontHeight = fontMetrics.getHeight();
  
          // create hatch marks and grid lines for y-axis.
          for (int i = 0; i < NUMBER_Y_DIVISIONS + 1; i++) {
              var x1 = PADDING + LABEL_PADDING;
              var x2 = POINT_WIDTH + PADDING + LABEL_PADDING;
              var y = height - ((i * (height - PADDING * 2 - LABEL_PADDING)) / NUMBER_Y_DIVISIONS + PADDING + LABEL_PADDING);
              if (length > 0) {
                  g.setColor(GRID_COLOR);
                  g.drawLine(PADDING + LABEL_PADDING + 1 + POINT_WIDTH, y, width - PADDING, y);
  
                  g.setColor(TEXT_COLOR);
                  var tickValue = minScore + ((scoreRange * i) / NUMBER_Y_DIVISIONS);
                  var yLabel = tickValue + "";
                  var labelWidth = fontMetrics.stringWidth(yLabel);
                  g.drawString(yLabel, x1 - labelWidth - 5, y + (fontHeight / 2) - 3);
              }
              g.drawLine(x1, y, x2, y);
          }
  
          // and for x-axis
          if (length > 1) {
              for (int i = 0; i < length; i++) {
                  var x = i * (width - PADDING * 2 - LABEL_PADDING) / (length - 1) + PADDING + LABEL_PADDING;
                  var y1 = height - PADDING - LABEL_PADDING;
                  var y2 = y1 - POINT_WIDTH;
                  if ((i % ((int) ((length / 20.0)) + 1)) == 0) {
                      g.setColor(GRID_COLOR);
                      g.drawLine(x, height - PADDING - LABEL_PADDING - 1 - POINT_WIDTH, x, PADDING);
  
                      g.setColor(Color.BLACK);
                  }
                  g.drawLine(x, y1, x, y2);
              }
          }
  
          // create x and y axes
          g.drawLine(PADDING + LABEL_PADDING, height - PADDING - LABEL_PADDING, PADDING + LABEL_PADDING, PADDING);
          g.drawLine(PADDING + LABEL_PADDING, height - PADDING - LABEL_PADDING, width - PADDING, height - PADDING - LABEL_PADDING);
  
          g.setColor(TEXT_COLOR);
          var labelWidth = fontMetrics.stringWidth(xLabel);
          var labelX = ((PADDING + LABEL_PADDING) + (width - PADDING)) / 2;
          var labelY = height - PADDING - LABEL_PADDING;
          g.drawString(xLabel, labelX - labelWidth / 2, labelY + fontHeight + 3);
  
          var oldStroke = g.getStroke();
          g.setColor(lineColor);
          g.setStroke(GRAPH_STROKE);
  
          var xScale = ((double) width - (2 * PADDING) - LABEL_PADDING) / (length - 1);
          var yScale = ((double) height - 2 * PADDING - LABEL_PADDING) / scoreRange;
  
          List<Point> graphPoints = new ArrayList<>(length);
          for (int i = 0; i < length; i++) {
              var x1 = (int) (i * xScale + PADDING + LABEL_PADDING);
              var y1 = (int) ((maxScore - values.get(i)) * yScale + PADDING);
              graphPoints.add(new Point(x1, y1));
          }
  
          for (int i = 0; i < graphPoints.size() - 1; i++) {
              var x1 = graphPoints.get(i).x;
              var y1 = graphPoints.get(i).y;
              var x2 = graphPoints.get(i + 1).x;
              var y2 = graphPoints.get(i + 1).y;
              g.drawLine(x1, y1, x2, y2);
          }
  
          var drawDots = width > (length * POINT_WIDTH);
          if (drawDots) {
              g.setStroke(oldStroke);
              g.setColor(pointColor);
              for (Point graphPoint : graphPoints) {
                  var x = graphPoint.x - POINT_WIDTH / 2;
                  var y = graphPoint.y - POINT_WIDTH / 2;
                  //noinspection SuspiciousNameCombination
                  g.fillOval(x, y, POINT_WIDTH, POINT_WIDTH);
              }
          }
      }
  
      private void calculateExtremum() {
          if (!variableExtreme) return;
  
          minScore = Integer.MAX_VALUE;
          maxScore = Integer.MIN_VALUE;
          for (int value : values) {
              minScore = Math.min(minScore, value);
              maxScore = Math.max(maxScore, value);
          }
  
          minScore = Math.min(MIN_SCORE_THRESHOLD, minScore);
          maxScore = (int) Math.max(MAX_SCORE_THRESHOLD, maxScore * 1.2);
      }
  }
  