Add tax breakdown details to transactions

src/main/java/com/yourorg/servershop/gui/SellMenu.java

@@ -52,21 +52,30 @@ public void refresh(Player p) {
     }
 
     private void sellAll(Player p) {
-        double total = 0.0; int stacks = 0;
+        double subtotal = 0.0; double taxTotal = 0.0; double total = 0.0; int stacks = 0; int qtyTotal = 0;
+        double taxRate = plugin.getConfig().getDouble("taxRate", 0.0);
         for (int i = 0; i < p.getInventory().getSize(); i++) {
             ItemStack s = p.getInventory().getItem(i);
             if (s == null) continue; var m = s.getType();
             var e = plugin.catalog().get(m).orElse(null); if (e == null || !e.canSell()) continue;
             int qty = s.getAmount();
             double unit = plugin.shop().priceSell(m);
             double amount = unit * qty;
-            total += amount; stacks++;
+            double tax = amount * taxRate;
+            double payout = amount - tax;
+            subtotal += amount; taxTotal += tax; total += payout; stacks++; qtyTotal += qty;
             p.getInventory().setItem(i, null);
-            plugin.logger().logAsync(new com.yourorg.servershop.logging.Transaction(java.time.Instant.now(), p.getName(), com.yourorg.servershop.logging.Transaction.Type.SELL, m, qty, amount));
+            plugin.logger().logAsync(new com.yourorg.servershop.logging.Transaction(java.time.Instant.now(), p.getName(), com.yourorg.servershop.logging.Transaction.Type.SELL, m, qty, payout));
             // TODO: consider calling plugin.dynamic().adjustOnSell(m, qty) per TODO list
         }
         if (total > 0) plugin.economy().depositPlayer(p, total);
         p.sendMessage(plugin.prefixed(plugin.getConfig().getString("messages.soldall").replace("%count%", String.valueOf(stacks)).replace("%total%", String.format("%.2f", total))));
+        if (qtyTotal > 0) {
+            double avgUnit = subtotal / qtyTotal;
+            String breakdown = org.bukkit.ChatColor.translateAlternateColorCodes('&',
+                    "&6$"+String.format("%.2f", avgUnit)+" &7× &e"+qtyTotal+" &7→ &c$"+String.format("%.2f", taxTotal)+" &7→ &a$"+String.format("%.2f", total));
+            p.sendMessage(plugin.prefixed(breakdown));
+        }
         refresh(p);
     }
 

src/main/java/com/yourorg/servershop/shop/ShopService.java

@@ -20,7 +20,10 @@ public Optional<String> buy(Player p, Material mat, int qty) {
         String cat = plugin.catalog().categoryOf(mat);
         if (!plugin.categorySettings().isEnabled(cat)) return Optional.of("Category disabled: "+cat);
         double unit = plugin.dynamic().buyPrice(mat, opt.get().buyPrice());
-        double total = unit * qty;
+        double subtotal = unit * qty;
+        double taxRate = plugin.getConfig().getDouble("taxRate", 0.0);
+        double tax = subtotal * taxRate;
+        double total = subtotal + tax;
         var econ = plugin.economy();
         if (econ.getBalance(p) + 1e-9 < total) {
             double need = Math.max(0, total - econ.getBalance(p));
@@ -34,6 +37,9 @@ public Optional<String> buy(Player p, Material mat, int qty) {
         plugin.dynamic().adjustOnBuy(mat, qty);
         plugin.logger().logAsync(new Transaction(Instant.now(), p.getName(), Transaction.Type.BUY, mat, qty, total));
         p.sendMessage(plugin.prefixed(msg("purchased").replace("%qty%", String.valueOf(qty)).replace("%material%", mat.name()).replace("%price%", fmt(total))));
+        String breakdown = org.bukkit.ChatColor.translateAlternateColorCodes('&',
+                "&6$"+fmt(unit)+" &7× &e"+qty+" &7→ &c$"+fmt(tax)+" &7→ &a$"+fmt(total));
+        p.sendMessage(plugin.prefixed(breakdown));
         return Optional.empty();
     }
 
@@ -45,11 +51,17 @@ public Optional<String> sell(Player p, Material mat, int qty) {
         int removed = removeFromInventory(p, mat, qty);
         if (removed <= 0) return Optional.of("You don't have that.");
         double unit = plugin.dynamic().sellPrice(mat, opt.get().sellPrice());
-        double total = unit * removed;
+        double subtotal = unit * removed;
+        double taxRate = plugin.getConfig().getDouble("taxRate", 0.0);
+        double tax = subtotal * taxRate;
+        double total = subtotal - tax;
         plugin.economy().depositPlayer(p, total);
         plugin.dynamic().adjustOnSell(mat, removed);
         plugin.logger().logAsync(new Transaction(Instant.now(), p.getName(), Transaction.Type.SELL, mat, removed, total));
         p.sendMessage(plugin.prefixed(msg("sold").replace("%qty%", String.valueOf(removed)).replace("%material%", mat.name()).replace("%price%", fmt(total))));
+        String breakdown = org.bukkit.ChatColor.translateAlternateColorCodes('&',
+                "&6$"+fmt(unit)+" &7× &e"+removed+" &7→ &c$"+fmt(tax)+" &7→ &a$"+fmt(total));
+        p.sendMessage(plugin.prefixed(breakdown));
         return Optional.empty();
     }
 

src/main/resources/config.yml

@@ -1,5 +1,6 @@
 messages:
   prefix: '&6[Shop] &7'
+taxRate: 0.0
 weekly:
   count: 6
   discount: 0.80