start fishing user storage

src/main/java/xyz/oribuin/fishing/api/economy/Currency.java

@@ -4,5 +4,6 @@ public enum Currency {
     VAULT, // Vault economy plugin
     ENTROPY, // Entropy
     FISH_EXP, // Fish experience
-    PLAYER_XP // Player experience
+    PLAYER_XP, // Player experience
+    SKILL_POINTS, // Skill points
 }

src/main/java/xyz/oribuin/fishing/manager/ConfigurationManager.java

@@ -1,15 +1,16 @@
 package xyz.oribuin.fishing.manager;
 
-import xyz.oribuin.fishing.FishingPlugin;
 import dev.rosewood.rosegarden.RosePlugin;
 import dev.rosewood.rosegarden.config.CommentedFileConfiguration;
 import dev.rosewood.rosegarden.config.RoseSetting;
 import dev.rosewood.rosegarden.manager.AbstractConfigurationManager;
+import xyz.oribuin.fishing.FishingPlugin;
 
 public class ConfigurationManager extends AbstractConfigurationManager {
 
     public enum Setting implements RoseSetting {
-      ;
+        REQUIRED_XP_FORMULA("required-xp-formula", "%level% * 625", "The formula to calculate the required experience to level up per level"),
+        ;
 
         private final String key;
         private final Object defaultValue;

src/main/java/xyz/oribuin/fishing/storage/FishingUser.java

@@ -0,0 +1,71 @@
+package xyz.oribuin.fishing.storage;
+
+import dev.rosewood.rosegarden.utils.StringPlaceholders;
+import xyz.oribuin.fishing.manager.ConfigurationManager.Setting;
+import xyz.oribuin.fishing.util.FishUtils;
+
+import java.util.UUID;
+
+public class FishingUser {
+
+    private final UUID uuid;
+    private int entropy;
+    private int level;
+    private int experience;
+    private int skillPoints;
+
+    public FishingUser(UUID uuid) {
+        this.uuid = uuid;
+        this.entropy = 0;
+        this.level = 1;
+        this.experience = 0;
+        this.skillPoints = 0;
+    }
+
+    /**
+     * Check the required experience to level up based on the current level
+     *
+     * @return The required experience to level up
+     */
+    public int getXpToNextLevel() {
+        StringPlaceholders placeholders = StringPlaceholders.of("level", this.level);
+        return (int) FishUtils.evaluate(placeholders.apply(Setting.REQUIRED_XP_FORMULA.getString()));
+    }
+
+    public UUID uuid() {
+        return this.uuid;
+    }
+
+    public int entropy() {
+        return this.entropy;
+    }
+
+    public void entropy(int entropy) {
+        this.entropy = entropy;
+    }
+
+    public int level() {
+        return this.level;
+    }
+
+    public void level(int level) {
+        this.level = level;
+    }
+
+    public int experience() {
+        return this.experience;
+    }
+
+    public void experience(int experience) {
+        this.experience = experience;
+    }
+
+    public int skillCaught() {
+        return this.skillPoints;
+    }
+
+    public void skillCaught(int skillCaught) {
+        this.skillPoints = skillCaught;
+    }
+
+}