content: package tanks;
  
  import tanks.gui.screen.leveleditor.selector.MetadataSelector;
  import tanks.tank.Tank;
  import tanks.tankson.MetadataProperty;
  
  import java.lang.reflect.Field;
  import java.util.*;
  
  public abstract class GameObject
  {
      public double posX, posY, posZ;
  
      public boolean draggable = false;
  
      public static HashMap<Class<? extends GameObject>, LinkedHashMap<String, MetadataSelector>> metadataPropertiesByClass = new HashMap<>();
  
      /**
       * If you want a subclass to use a different id for a selector (for example, have the player and ai tank teams use separate selectors in the editor),
       * you can add to the map here to replace a selector id with another one for that subclass specifically.
       */
      public HashMap<String, String> overrideMetadataPropertyIDs = new HashMap<>();
  
      public String primaryMetadataID = null;
      public String secondaryMetadataID = null;
  
      public static HashMap<Class<? extends GameObject>, MetadataSelector> primaryMetadataField = new HashMap<>();
      public static HashMap<Class<? extends GameObject>, MetadataSelector> secondaryMetadataField = new HashMap<>();
  
      public String getMetadata()
      {
          return "";
      }
  
      public void setMetadata(String meta)
      {
  
      }
  
      public void refreshMetadata()
      {
  
      }
  
      public double getSize()
      {
          return 0;
      }
  
      protected void setupMetadataFields()
      {
          try
          {
              if (!metadataPropertiesByClass.containsKey(this.getClass()))
              {
                  LinkedHashMap<String, MetadataSelector> props = new LinkedHashMap<>();
                  metadataPropertiesByClass.put(this.getClass(), props);
  
                  for (Field f : this.getClass().getFields())
                  {
                      MetadataProperty a = f.getAnnotation(MetadataProperty.class);
                      if (a != null)
                      {
                          MetadataSelector s = Game.registryMetadataSelectors.getEntry(a.selector()).getConstructor(Field.class).newInstance(f);
                          String id = a.id();
                          if (overrideMetadataPropertyIDs.get(id) != null)
                              id = overrideMetadataPropertyIDs.get(id);
  
                          s.id = id;
                          props.put(id, s);
  
                          if (id.equals(this.primaryMetadataID))
                              primaryMetadataField.put(this.getClass(), s);
  
                          if (id.equals(this.secondaryMetadataID))
                              secondaryMetadataField.put(this.getClass(), s);
                      }
                  }
              }
          }
          catch (Exception e)
          {
              Game.exitToCrash(e);
          }
      }
  
      @Override
      public String toString()
      {
          return String.format(
              "%s@(%.0f,%.0f)",
              this instanceof Tank ? ((Tank) this).name : this.getClass().getSimpleName(),
              this.posX, this.posY
          );
      }
  
      public HashMap<String, MetadataSelector> getMetadataProperties()
      {
          this.setupMetadataFields();
          return metadataPropertiesByClass.get(this.getClass());
      }
  
      public MetadataSelector getMetadataProperty(String name)
      {
          this.setupMetadataFields();
          return metadataPropertiesByClass.get(this.getClass()).get(name);
      }
  
      public MetadataSelector getPrimaryMetadataProperty()
      {
          this.setupMetadataFields();
          return primaryMetadataField.get(this.getClass());
      }
  
      public MetadataSelector getSecondaryMetadataProperty()
      {
          this.setupMetadataFields();
          return secondaryMetadataField.get(this.getClass());
      }
  
      static double pi_over_4 = Math.PI / 4;
      static double fastAtan(double a)
      {
          if (a < -1 || a > 1)
              return Math.atan(a);
  
          return pi_over_4 * a - a * (Math.abs(a) - 1) * (0.2447 + 0.0663 * Math.abs(a));
      }
  
      public static double getPolarDirection(double x, double y)
      {
          double angle = 0;
          if (x > 0)
              angle = Math.atan(y / x);
          else if (x < 0)
              angle = Math.atan(y / x) + Math.PI;
          else
          {
              if (y > 0)
                  angle = Math.PI / 2;
              else if (y < 0)
                  angle = Math.PI * 3 / 2;
          }
  
          return angle;
      }
  
      public static double distanceBetween(double x1, double y1, double x2, double y2)
      {
          return Math.sqrt(sqDistBetw(x1, y1, x2, y2));
      }
  
      public static double sqDistBetw(double x1, double y1, double x2, double y2)
      {
          return (x1 - x2)*(x1 - x2) + (y1 - y2)*(y1 - y2);
      }
  
      public static double sqDistBetw(final GameObject a, final GameObject b)
      {
          return sqDistBetw(a.posX, a.posY, b.posX, b.posY);
      }
  
      public static boolean withinRadius(final GameObject a, final GameObject b, double range)
      {
          return sqDistBetw(a, b) < range * range;
      }
  
      public static double distanceBetween(final GameObject a, final GameObject b)
      {
          return distanceBetween(a.posX, a.posY, b.posX, b.posY);
      }
  
      public static double angleBetween(double a, double b)
      {
          return (a - b + Math.PI * 3) % (Math.PI*2) - Math.PI;
      }
  
      public static double absoluteAngleBetween(double a, double b)
      {
          return Math.abs((a - b + Math.PI * 3) % (Math.PI * 2) - Math.PI);
      }
  }
  