Add functions to the GUI.

plugin/src/main/java/com/alttd/cometskyblock/configuration/MessageConfiguration.java

@@ -20,7 +20,21 @@ public class MessageConfiguration implements Configuration {
         SetHome setHome = new SetHome();
         @ConfigSerializable @Getter
         public static class SetHome {
+            String homeSet = "You have set your island home to your current location.";
+        }
 
+        CobbeGen cobbeGen = new CobbeGen();
+        @ConfigSerializable @Getter
+        public static class CobbeGen {
+            String requiredLevel = "You must reach <islandlevel> before upgrading to the next cobblestone generation level.";
+            String upgraded = "Your cobblestone generation is now level <level>.";
+        }
+
+        Level level = new Level();
+        @ConfigSerializable @Getter
+        public static class Level {
+            String requiredXp = "You need <requiredxp> to level up your island.";
+            String upgraded = "Your island has leveled up!";
         }
     }
 

plugin/src/main/java/com/alttd/cometskyblock/gui/GUIInventory.java

@@ -3,6 +3,8 @@ package com.alttd.cometskyblock.gui;
 import com.alttd.cometskyblock.island.Island;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.minimessage.MiniMessage;
+import net.kyori.adventure.text.minimessage.tag.resolver.Placeholder;
+import net.kyori.adventure.text.minimessage.tag.resolver.TagResolver;
 import org.bukkit.Bukkit;
 import org.bukkit.Material;
 import org.bukkit.OfflinePlayer;
@@ -106,7 +108,7 @@ public abstract class GUIInventory implements GUI, InventoryHolder {
         for (int i = 0; i < 9; ++i) {
             addButton(i, createMenuButton(Material.BLACK_STAINED_GLASS_PANE, "", new ArrayList<>(), event -> {}));
         }
-        addButton(5, createIslandMenuButton(island.owner(), event -> {}));
+        addButton(4, createIslandMenuButton(island.owner(), event -> {}));
     }
 
     public void open(Player player) {
@@ -173,10 +175,13 @@ public abstract class GUIInventory implements GUI, InventoryHolder {
 
                     SkullMeta meta = (SkullMeta) skull.getItemMeta();
                     meta.setPlayerProfile(offlinePlayer.getPlayerProfile());
-
+                    var placeholders = TagResolver.resolver(
+                            Placeholder.unparsed("islandlevel", island.level() + ""),
+                            Placeholder.unparsed("islandmembers", island.members().size() + "")
+                    );
                     List<Component> metaLore = new ArrayList<>();
-                    for (String loreString : List.of("Island Level : <islandlevel>", "Members: <islandmembers>", "")) {
+                    for (String loreString : List.of("Island Level : <gold><islandlevel>", "Members: <gold><islandmembers>", "")) {
-                        metaLore.add(MiniMessage.miniMessage().deserialize(loreString));
+                        metaLore.add(MiniMessage.miniMessage().deserialize(loreString, placeholders));
                     }
 
                     meta.lore(metaLore);

plugin/src/main/java/com/alttd/cometskyblock/island/gui/MembersGUI.java

@@ -37,7 +37,10 @@ public class MembersGUI extends GUIInventory {
 
         int startIndex = pageIndex * 45;
         for (int i = startIndex; i < island.members().size(); i++) {
-            GUIButton guiButton = createPlayerHeadMenuButton(island.members().get(i), event -> {});
+            GUIButton guiButton = createPlayerHeadMenuButton(island.members().get(i), event -> {
+                // TODO - show last online, some player info
+                // Island owner can kick from gui
+            });
             if (!addItem(guiButton)) {
                 createNextPageButton(player);
                 break;

plugin/src/main/java/com/alttd/cometskyblock/island/gui/SettingsGUI.java

@@ -47,6 +47,7 @@ public class SettingsGUI extends GUIInventory {
                 return;
             }
             player.getWorld().setSpawnLocation(player.getLocation());
+            player.sendRichMessage(islandMessages.setHome().homeSet());
         }));
         super.decorate(player);
     }

plugin/src/main/java/com/alttd/cometskyblock/island/gui/UpgradesGUI.java

@@ -1,9 +1,13 @@
 package com.alttd.cometskyblock.island.gui;
 
 import com.alttd.cometskyblock.CometSkyBlockPlugin;
+import com.alttd.cometskyblock.configuration.MessageConfiguration;
 import com.alttd.cometskyblock.gui.GUIInventory;
+import com.alttd.cometskyblock.island.CobblestoneGeneratorLevel;
 import com.alttd.cometskyblock.island.Island;
+import com.alttd.cometskyblock.util.Experience;
 import net.kyori.adventure.text.minimessage.MiniMessage;
+import net.kyori.adventure.text.minimessage.tag.resolver.Placeholder;
 import org.bukkit.Bukkit;
 import org.bukkit.Material;
 import org.bukkit.World;
@@ -12,6 +16,7 @@ import org.bukkit.entity.Player;
 import org.bukkit.inventory.Inventory;
 
 import java.util.ArrayList;
+import java.util.List;
 
 public class UpgradesGUI extends GUIInventory {
 
@@ -27,6 +32,7 @@ public class UpgradesGUI extends GUIInventory {
     @Override
     public void decorate(Player player) {
         makeMenuBar();
+        MessageConfiguration.Island islandMessages = CometSkyBlockPlugin.instance().messagesConfiguration().get().island();
         // Todo - move to handlers, add costs, validation ...
         // WorldBorder
         addButton(10, createMenuButton(Material.GRASS_BLOCK, "Expand The world border", new ArrayList<>(), event -> {
@@ -40,12 +46,50 @@ public class UpgradesGUI extends GUIInventory {
         }));
         // Cobble Gen
         addButton(11, createMenuButton(Material.COBBLESTONE, "Upgrade your cobble stone generator", new ArrayList<>(), event -> {
+            int requiredIslandLevel = getRequiredIslandLevel(island.cobblegenLevel() + 1);
+            if (island.level() < requiredIslandLevel) {
+                player.sendRichMessage(islandMessages.cobbeGen().requiredLevel(), Placeholder.parsed("islandlevel", "<gold>" + requiredIslandLevel + "</gold>"));
+                return;
+            }
             island.cobblegenLevel(island.cobblegenLevel() + 1);
+            player.sendRichMessage(islandMessages.cobbeGen().upgraded(), Placeholder.parsed("level", "<gold>" + island.cobblegenLevel() + "</gold>"));
         }));
         // Level
-        addButton(12, createMenuButton(Material.ENCHANTING_TABLE, "Increase your island level", new ArrayList<>(), event -> {}));
+        addButton(12, createMenuButton(Material.EXPERIENCE_BOTTLE, "Increase your island level", List.of(
+                "<white>Use your experience to upgrade your island level.",
+                "",
+                "<white><gold>" + Experience.getExpToNextIslandLevel(island.level()) + "</gold> experience required to level up!"
+        ),event -> {
+            int xp = Experience.getExpToNextIslandLevel(island.level());
+            if (player.getTotalExperience() < xp) {
+                player.sendRichMessage(islandMessages.level().requiredXp(), Placeholder.parsed("requiredxp", "<gold>" + xp + "</gold>"));
+                return;
+            }
+            Experience.changeExp(player, player.getTotalExperience() - xp);
+        }));
         // Difficulty
         super.decorate(player);
     }
 
+    Integer getRequiredIslandLevel(int generatorLevel) {
+        CobblestoneGeneratorLevel level = getLevel(generatorLevel);
+        return level != null ? level.islandLevel() : 0;
+    }
+
+    CobblestoneGeneratorLevel getLevel(int generatorLevel) {
+        if (generatorLevel == 0) {
+            return null;
+        }
+        CometSkyBlockPlugin plugin = CometSkyBlockPlugin.instance();
+        if (plugin.cobblestoneGeneratorConfiguration().get().levels().size() < generatorLevel) {
+            return getLevel(generatorLevel - 1);
+        }
+        for (CobblestoneGeneratorLevel level : plugin.cobblestoneGeneratorConfiguration().get().levels()) {
+            if (level.level() == generatorLevel) {
+                return level;
+            }
+        }
+        return null;
+    }
+
 }

plugin/src/main/java/com/alttd/cometskyblock/listeners/CobbestoneGeneratorListener.java

@@ -69,26 +69,6 @@ public class CobbestoneGeneratorListener implements Listener {
         return Material.COBBLESTONE;
     }
 
-    Integer getRequiredIslandLevel(int generatorLevel) {
-        CobblestoneGeneratorLevel level = getLevel(generatorLevel);
-        return level != null ? level.islandLevel() : 0;
-    }
-
-    CobblestoneGeneratorLevel getLevel(int generatorLevel) {
-        if (generatorLevel == 0) {
-            return null;
-        }
-        if (plugin.cobblestoneGeneratorConfiguration().get().levels().size() < generatorLevel) {
-            return getLevel(generatorLevel - 1);
-        }
-        for (CobblestoneGeneratorLevel level : plugin.cobblestoneGeneratorConfiguration().get().levels()) {
-            if (level.level() == generatorLevel) {
-                return level;
-            }
-        }
-        return null;
-    }
-
     boolean relativeEqualsMaterial(Block block, Material material) {
         return block.getRelative(BlockFace.NORTH).getType().equals(material)
                 || block.getRelative(BlockFace.EAST).getType().equals(material)

plugin/src/main/java/com/alttd/cometskyblock/util/Experience.java

@@ -0,0 +1,136 @@
+package com.alttd.cometskyblock.util;
+
+import org.bukkit.entity.Player;
+
+/**
+ * Based on gist
+ * <a href="https://gist.github.com/Jikoo/30ec040443a4701b8980">A utility for managing player experience.</a>
+ */
+public final class Experience {
+
+    /**
+     * Calculate a player's total experience based on level and progress to next.
+     *
+     * @param player the Player
+     * @return the amount of experience the Player has
+     *
+     * @see <a href=http://minecraft.gamepedia.com/Experience#Leveling_up>Experience#Leveling_up</a>
+     */
+    public static int getExp(Player player) {
+        return getExpFromLevel(player.getLevel())
+                + Math.round(getExpToNext(player.getLevel()) * player.getExp());
+    }
+
+    /**
+     * Calculate total experience based on level.
+     *
+     * @param level the level
+     * @return the total experience calculated
+     *
+     * @see <a href=http://minecraft.gamepedia.com/Experience#Leveling_up>Experience#Leveling_up</a>
+     */
+    public static int getExpFromLevel(int level) {
+        if (level > 30) {
+            return (int) (4.5 * level * level - 162.5 * level + 2220);
+        }
+        if (level > 15) {
+            return (int) (2.5 * level * level - 40.5 * level + 360);
+        }
+        return level * level + 6 * level;
+    }
+
+    /**
+     * Calculate level (including progress to next level) based on total experience.
+     *
+     * @param exp the total experience
+     * @return the level calculated
+     */
+    public static double getLevelFromExp(long exp) {
+        int level = getIntLevelFromExp(exp);
+
+        // Get remaining exp progressing towards next level. Cast to float for next bit of math.
+        float remainder = exp - (float) getExpFromLevel(level);
+
+        // Get level progress with float precision.
+        float progress = remainder / getExpToNext(level);
+
+        // Slap both numbers together and call it a day. While it shouldn't be possible for progress
+        // to be an invalid value (value < 0 || 1 <= value)
+        return ((double) level) + progress;
+    }
+
+    /**
+     * Calculate level based on total experience.
+     *
+     * @param exp the total experience
+     * @return the level calculated
+     */
+    public static int getIntLevelFromExp(long exp) {
+        if (exp > 1395) {
+            return (int) ((Math.sqrt(72 * exp - 54215D) + 325) / 18);
+        }
+        if (exp > 315) {
+            return (int) (Math.sqrt(40 * exp - 7839D) / 10 + 8.1);
+        }
+        if (exp > 0) {
+            return (int) (Math.sqrt(exp + 9D) - 3);
+        }
+        return 0;
+    }
+
+    /**
+     * Get the total amount of experience required to progress to the next level.
+     *
+     * @param level the current level
+     *
+     * @see <a href=http://minecraft.gamepedia.com/Experience#Leveling_up>Experience#Leveling_up</a>
+     */
+    private static int getExpToNext(int level) {
+        if (level >= 30) {
+            // Simplified formula. Internal: 112 + (level - 30) * 9
+            return level * 9 - 158;
+        }
+        if (level >= 15) {
+            // Simplified formula. Internal: 37 + (level - 15) * 5
+            return level * 5 - 38;
+        }
+        // Internal: 7 + level * 2
+        return level * 2 + 7;
+    }
+
+    /**
+     * Change a Player's experience.
+     *
+     * <p>This method is preferred over {@link Player#giveExp(int)}.
+     * <br>In older versions the method does not take differences in exp per level into account.
+     * This leads to overlevelling when granting players large amounts of experience.
+     * <br>In modern versions, while differing amounts of experience per level are accounted for, the
+     * approach used is loop-heavy and requires an excessive number of calculations, which makes it
+     * quite slow.
+     *
+     * @param player the Player affected
+     * @param exp the amount of experience to add or remove
+     */
+    public static void changeExp(Player player, int exp) {
+        exp += getExp(player);
+
+        if (exp < 0) {
+            exp = 0;
+        }
+
+        double levelAndExp = getLevelFromExp(exp);
+        int level = (int) levelAndExp;
+        player.setLevel(level);
+        player.setExp((float) (levelAndExp - level));
+    }
+
+    public static int getExpToNextIslandLevel(int level) {
+        if (level <= 15) {
+            return 2 * level + 7;
+        } else if (level <= 30) {
+            return 5 * level - 38;
+        } else {
+            return 9 * level - 158;
+        }
+    }
+}