Added min and max y settings (Resolves #2)

Max y will be 127 in the nether by default. Use the -maxY parameter to change it. Also once a maxY is set it will try to find a random y between the values if the highest block is above the max y value.

randomteleport-plugin/src/main/java/de/themoep/randomteleport/RandomTeleport.java

@@ -149,6 +149,20 @@ public class RandomTeleport extends JavaPlugin implements RandomTeleportAPI {
             }
             return false;
         }));
+        addOptionParser(new SimpleOptionParser(array("miny"), (searcher, args) -> {
+            if (args.length > 0) {
+                searcher.setMinY(Integer.parseInt(args[0]));
+                return true;
+            }
+            return false;
+        }));
+        addOptionParser(new SimpleOptionParser(array("maxy"), (searcher, args) -> {
+            if (args.length > 0) {
+                searcher.setMaxY(Integer.parseInt(args[0]));
+                return true;
+            }
+            return false;
+        }));
         addOptionParser(new SimpleOptionParser(array("w", "world"), (searcher, args) -> {
             if (args.length > 0) {
                 World world = getServer().getWorld(args[0]);

randomteleport-plugin/src/main/java/de/themoep/randomteleport/searcher/RandomSearcher.java

@@ -28,6 +28,7 @@ import io.papermc.lib.PaperLib;
 import org.apache.commons.lang.Validate;
 import org.bukkit.Chunk;
 import org.bukkit.Location;
+import org.bukkit.World;
 import org.bukkit.command.CommandSender;
 import org.bukkit.entity.Entity;
 
@@ -68,6 +69,8 @@ public class RandomSearcher {
     private Location center;
     private int minRadius = 0;
     private int maxRadius = Integer.MAX_VALUE;
+    private int minY = 0;
+    private int maxY;
     private boolean loadedOnly = false;
     private boolean generatedOnly = false;
     private int maxTries = 100;
@@ -85,6 +88,11 @@ public class RandomSearcher {
         setCenter(center);
         setMinRadius(minRadius);
         setMaxRadius(maxRadius);
+        if (center.getWorld().getEnvironment() == World.Environment.NETHER) {
+            maxY = 127;
+        } else {
+            maxY = center.getWorld().getMaxHeight();
+        }
         this.validators.getRaw().putAll(plugin.getLocationValidators().getRaw());
         Arrays.asList(validators).forEach(this.validators::add);
     }
@@ -216,6 +224,40 @@ public class RandomSearcher {
         this.maxRadius = maxRadius;
     }
 
+    /**
+     * Get the minimum Y
+     * @return The minimum Y, always positive and less than the max Y!
+     */
+    public int getMinY() {
+        return minY;
+    }
+
+    /**
+     * Set the minimum search Y
+     * @param minY The min Y; has to be positive and less than the max Y!
+     */
+    public void setMinY(int minY) {
+        Validate.isTrue(minY >= 0 && minY < maxY, "Min Y has to be positive and less than the max Y!");
+        this.minY = minY;
+    }
+
+    /**
+     * Get the maximum Y
+     * @return The maximum Y, always greater than the minimum Y
+     */
+    public int getMaxY() {
+        return maxY;
+    }
+
+    /**
+     * Set the maximum search Y
+     * @param maxY The max Y; has to be greater than the min Y!
+     */
+    public void setMaxY(int maxY) {
+        Validate.isTrue(maxY > minY, "Max Y has to be greater than the min Y!");
+        this.maxY = maxY;
+    }
+
     /**
      * By default it will search for coordinates in any chunk, even unloaded ones prompting the server to load new
      * chunks which might result in some performance impact if the server doesn't support async loading. This disables

randomteleport-plugin/src/main/java/de/themoep/randomteleport/searcher/validators/HeightValidator.java

@@ -32,9 +32,16 @@ public class HeightValidator extends LocationValidator {
     @Override
     public boolean validate(RandomSearcher searcher, Location location) {
         Block block = location.getWorld().getHighestBlockAt(location);
+        if (block.getY() > searcher.getMaxY()) {
+            block = location.getWorld().getBlockAt(
+                    block.getX(),
+                    searcher.getMinY() + searcher.getRandom().nextInt(searcher.getMaxY() - searcher.getMinY()),
+                    block.getZ()
+            );
+        }
         while (block.isEmpty()) {
             block = block.getRelative(BlockFace.DOWN);
-            if (block == null || block.getY() == 0) {
+            if (block == null || block.getY() < searcher.getMinY()) {
                 return false;
             }
         }

randomteleport-plugin/src/main/resources/plugin.yml

@@ -22,6 +22,8 @@ commands:
         > -b,-biome <biomename> [<biome 2> ...] - only teleport to this biome (multiple allowed, Bukkit biome names!)
         > -x,-xPos <x value> - x axis of the center point, if not set the player's x axis is used
         > -z,-zPos <z value> - z axis of the center point, if not set the player's z axis is used
+        > -minY <y value> - minimum y value that the random location should have (default: 0)
+        > -maxY <y value> - maximum y value that the random location should have (default: world height, half in nether)
         > -l,-loaded - only search loaded chunks for possible locations (might fail more often)
         > -g,-generated - only search generated chunks for possible locations
         > -c, -cooldown <seconds> - cooldown in seconds after which the player can use this teleporter again