feat: handle pay + improve tax system

api/src/main/java/dev/xhyrom/lighteco/api/model/currency/Currency.java

@@ -1,5 +1,7 @@
 package dev.xhyrom.lighteco.api.model.currency;
 
+import dev.xhyrom.lighteco.api.model.user.User;
+
 import java.math.BigDecimal;
 
 public abstract class Currency {
@@ -36,10 +38,10 @@ public abstract class Currency {
      * Used for payables
      *
      * @param amount The amount to calculate the tax for
-     * @return The tax
+     * @return Amount that should be taxed
      */
-    public BigDecimal calculateTax(BigDecimal amount) {
+    public BigDecimal calculateTax(User user, BigDecimal amount) {
-        return getDefaultBalance();
+        return BigDecimal.ZERO;
     };
 
     /**

bukkit/src/main/java/dev/xhyrom/lighteco/bukkit/manager/BukkitCommandManager.java

@@ -91,6 +91,18 @@ public class BukkitCommandManager extends AbstractCommandManager {
                             this.handleTake(sender, args, currency);
                         })
                 )
+                .withSubcommand(new CommandAPICommand("pay")
+                        .withPermission(permissionBase + "pay")
+                        .withArguments(
+                                new OfflinePlayerArgument("target"),
+                                currency.getProxy().getDecimalPlaces() > 0
+                                        ? new DoubleArgument("amount", 1)
+                                        : new IntegerArgument("amount", 1)
+                        )
+                        .executesPlayer((sender, args) -> {
+                            this.handlePay(sender, args, currency);
+                        })
+                )
                 .withSubcommand(balanceCommands.get(0))
                 .withSubcommands(balanceCommands.get(1))
                 .register();
@@ -147,7 +159,7 @@ public class BukkitCommandManager extends AbstractCommandManager {
                 });
     }
 
-    public void handleTake(CommandSender originalSender, CommandArguments args, Currency currency) {
+    private void handleTake(CommandSender originalSender, CommandArguments args, Currency currency) {
         BukkitCommandSender sender = new BukkitCommandSender(originalSender, this.audienceFactory);
         OfflinePlayer target = (OfflinePlayer) args.get("target");
         BigDecimal amount = BigDecimal.valueOf(Double.parseDouble(args.getRaw("amount")));
@@ -162,4 +174,20 @@ public class BukkitCommandManager extends AbstractCommandManager {
                     this.onTake(sender, currency, result, amount);
                 });
     }
+
+    private void handlePay(CommandSender originalSender, CommandArguments args, Currency currency) {
+        BukkitCommandSender sender = new BukkitCommandSender(originalSender, this.audienceFactory);
+        OfflinePlayer target = (OfflinePlayer) args.get("target");
+        BigDecimal amount = BigDecimal.valueOf(Double.parseDouble(args.getRaw("amount")));
+
+        if (!this.canUse(sender)) return;
+
+        this.plugin.getUserManager().loadUser(target.getUniqueId())
+                .thenAcceptAsync(result -> {
+                    String name = target.getName() != null ? target.getName() : args.getRaw("target");
+                    result.setUsername(name);
+
+                    this.onPay(sender, currency, result, amount);
+                });
+    }
 }

bukkittest/src/main/java/dev/xhyrom/lighteco/bukkittest/TestCurrency.java

@@ -24,9 +24,4 @@ public class TestCurrency extends Currency {
     public BigDecimal getDefaultBalance() {
         return BigDecimal.ZERO;
     }
-
-    @Override
-    public BigDecimal calculateTax(BigDecimal amount) {
-        return BigDecimal.ZERO;
-    }
 }

bukkittest/src/main/java/dev/xhyrom/lighteco/bukkittest/TestCurrency2.java

@@ -1,6 +1,7 @@
 package dev.xhyrom.lighteco.bukkittest;
 
 import dev.xhyrom.lighteco.api.model.currency.Currency;
+import dev.xhyrom.lighteco.api.model.user.User;
 
 import java.math.BigDecimal;
 
@@ -31,7 +32,7 @@ public class TestCurrency2 extends Currency {
     }
 
     @Override
-    public BigDecimal calculateTax(BigDecimal amount) {
+    public BigDecimal calculateTax(User user, BigDecimal amount) {
-        return BigDecimal.ZERO;
+        return amount.multiply(BigDecimal.valueOf(0.2));
     }
 }

common/src/main/java/dev/xhyrom/lighteco/common/manager/command/AbstractCommandManager.java

@@ -10,6 +10,7 @@ import java.math.BigDecimal;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
 
 public abstract class AbstractCommandManager implements CommandManager {
     protected final LightEcoPlugin plugin;
@@ -110,4 +111,30 @@ public abstract class AbstractCommandManager implements CommandManager {
         this.plugin.getUserManager().saveUser(target)
                 .thenAccept(v -> removeFromMustWait(target.getUniqueId(), sender.getUniqueId()));
     }
+
+    @Override
+    public void onPay(CommandSender sender, Currency currency, User target, BigDecimal amount) {
+        addToMustWait(sender.getUniqueId(), target.getUniqueId());
+
+        User user = this.plugin.getUserManager().getIfLoaded(sender.getUniqueId());
+
+        // calculate tax using Currency#calculateTax
+        BigDecimal tax = currency.getProxy().calculateTax(user.getProxy(), amount);
+
+        // subtract tax from amount
+        amount = amount.subtract(tax);
+
+        target.setBalance(currency, target.getBalance(currency).add(amount));
+        user.setBalance(currency, user.getBalance(currency).subtract(amount));
+
+       // send message and also include tax rate (percentage) with tax amount
+        sender.sendMessage(
+                miniMessage.deserialize("<yellow>Paid <gold>" + amount.toPlainString() + " <yellow>" + currency.getIdentifier() + " to " + target.getUsername() + " with a tax rate of <gold>" + tax + "% <yellow>(<gold>" + tax.toPlainString() + " <yellow>" + currency.getIdentifier() + ")")
+        );
+
+        CompletableFuture.allOf(
+                this.plugin.getUserManager().saveUser(user),
+                this.plugin.getUserManager().saveUser(target)
+        ).thenAccept(v -> removeFromMustWait(sender.getUniqueId(), target.getUniqueId()));
+    }
 }

common/src/main/java/dev/xhyrom/lighteco/common/manager/command/CommandManager.java

@@ -18,4 +18,5 @@ public interface CommandManager {
     void onSet(CommandSender sender, Currency currency, User target, BigDecimal amount);
     void onGive(CommandSender sender, Currency currency, User target, BigDecimal amount);
     void onTake(CommandSender sender, Currency currency, User target, BigDecimal amount);
+    void onPay(CommandSender sender, Currency currency, User target, BigDecimal amount);
 }