Cleans up the function for paying for book printing

src/main/java/net/knarcraft/bookswithoutborders/BooksWithoutBorders.java

@@ -12,6 +12,7 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.ListIterator;
 import java.util.Map;
+import java.util.Objects;
 
 import net.milkbowl.vault.economy.Economy;
 import org.bukkit.ChatColor;
@@ -25,6 +26,7 @@ import org.bukkit.configuration.file.YamlConfiguration;
 import org.bukkit.entity.Player;
 import org.bukkit.inventory.ItemFactory;
 import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.PlayerInventory;
 import org.bukkit.inventory.meta.BookMeta;
 import org.bukkit.inventory.meta.ItemMeta;
 import org.bukkit.plugin.Plugin;
@@ -400,6 +402,7 @@ public class BooksWithoutBorders extends JavaPlugin {
 
             //Player only commands
             if (sender instanceof Player) {
+                Player player = (Player) sender;
 
                 if (args[0].equalsIgnoreCase("savePublic")) {
                     if (!sender.hasPermission("bookswithoutborders.savepublic")) {
@@ -407,9 +410,9 @@ public class BooksWithoutBorders extends JavaPlugin {
                         return false;
                     }
 
-                    if (((Player) sender).getItemInHand().getType() == Material.WRITTEN_BOOK || ((Player) sender).getItemInHand().getType() == Material.WRITABLE_BOOK) {
+                    if (player.getItemInHand().getType() == Material.WRITTEN_BOOK || player.getItemInHand().getType() == Material.WRITABLE_BOOK) {
                         if (args.length == 2) {
-                            saveBook((Player) sender, args[1], true);
+                            saveBook(player, args[1], true);
                         } else {
                             saveBook((Player) sender, "false", true);
                         }
@@ -563,13 +566,13 @@ public class BooksWithoutBorders extends JavaPlugin {
                     }
 
                     ItemStack newBook;
-                    Player player = this.getServer().getPlayer(args[2]);
+                    Player receivingPlayer = this.getServer().getPlayer(args[2]);
-                    if (player == null) {
+                    if (receivingPlayer == null) {
                         sender.sendMessage(ChatColor.RED + "Player not found!");
                         return false;
                     }
 
-                    if (player.getInventory().firstEmpty() == -1) {
+                    if (receivingPlayer.getInventory().firstEmpty() == -1) {
                         sender.sendMessage(ChatColor.RED + "Receiving player must have space in their inventory to receive books!");
                         return false;
                     }
@@ -588,9 +591,9 @@ public class BooksWithoutBorders extends JavaPlugin {
                             newBook = loadBook(sender, cleanString(args[1]), "true", "player");
 
                         if (newBook != null) {
-                            player.getInventory().addItem(newBook);
+                            receivingPlayer.getInventory().addItem(newBook);
                             sender.sendMessage(ChatColor.GREEN + "Book sent!");
-                            player.sendMessage(ChatColor.GREEN + "Book received!");
+                            receivingPlayer.sendMessage(ChatColor.GREEN + "Book received!");
                             return true;
                         } else {
                             sender.sendMessage(ChatColor.RED + "Book failed to load!");
@@ -641,7 +644,18 @@ public class BooksWithoutBorders extends JavaPlugin {
                         return false;
                     }
 
-                    unsign((Player) sender);
+                    boolean hasBookInMainHand = player.getInventory().getItemInMainHand().getType() == Material.WRITTEN_BOOK;
+                    boolean hasBookInOffHand = player.getInventory().getItemInOffHand().getType() == Material.WRITTEN_BOOK;
+
+                    //Find which hand the player is using to hold the book. If holding one in each, throw an error
+                    if (hasBookInMainHand && hasBookInOffHand) {
+                        sender.sendMessage(ChatColor.RED + "You cannot un-sign two books at once. Please un-equip one " +
+                                "of the books you're holding!");
+                    } else if (hasBookInMainHand) {
+                        unSignHeldBook(player, true);
+                    } else if (hasBookInOffHand) {
+                        unSignHeldBook(player, false);
+                    }
                     return true;
                 }
 
@@ -668,9 +682,10 @@ public class BooksWithoutBorders extends JavaPlugin {
                                     return false;
                             }
 
-                            if (BooksHavePrice() && !sender.hasPermission("bookswithoutborders.bypassbookprice")) {
+                            if (BooksHavePrice() &&
-                                if (!printBook((Player) sender, Integer.parseInt(args[1])))
+                                    !sender.hasPermission("bookswithoutborders.bypassbookprice") &&
-                                    return false;
+                                    cannotPayForBookPrinting((Player) sender, Integer.parseInt(args[1]))) {
+                                return false;
                             }
 
                             ((Player) sender).getItemInHand().setAmount(((Player) sender).getItemInHand().getAmount() + Integer.parseInt(args[1]));
@@ -959,13 +974,13 @@ public class BooksWithoutBorders extends JavaPlugin {
                 }
 
                 ItemStack newBook;
-                Player player = this.getServer().getPlayer(args[2]);
+                Player receivingPlayer = this.getServer().getPlayer(args[2]);
-                if (player == null) {
+                if (receivingPlayer == null) {
                     sender.sendMessage(ChatColor.RED + "Player not found!");
                     return false;
                 }
 
-                if (player.getInventory().firstEmpty() == -1) {
+                if (receivingPlayer.getInventory().firstEmpty() == -1) {
                     sender.sendMessage(ChatColor.RED + "Receiving player must have space in their inventory to receive books!");
                     return false;
                 }
@@ -982,9 +997,9 @@ public class BooksWithoutBorders extends JavaPlugin {
                         newBook = loadBook(sender, cleanString(args[1]), "true", "public");
 
                     if (newBook != null) {
-                        player.getInventory().addItem(newBook);
+                        receivingPlayer.getInventory().addItem(newBook);
                         sender.sendMessage(ChatColor.GREEN + "Book sent!");
-                        player.sendMessage(ChatColor.GREEN + "Book received!");
+                        receivingPlayer.sendMessage(ChatColor.GREEN + "Book received!");
                         return true;
                     } else {
                         sender.sendMessage(ChatColor.RED + "Book failed to load!");
@@ -1420,9 +1435,10 @@ public class BooksWithoutBorders extends JavaPlugin {
         book.setAmount(numCopies);
 
         if (BooksHavePrice() && !sender.hasPermission("bookswithoutborders.bypassbookprice") &&
-                (dir.equalsIgnoreCase("public") || dir.equalsIgnoreCase("player") || dir.equalsIgnoreCase(""))) {
+                (dir.equalsIgnoreCase("public") || dir.equalsIgnoreCase("player") ||
-            if (!printBook((Player) sender, numCopies))
+                        dir.equalsIgnoreCase("")) &&
-                return null;
+                cannotPayForBookPrinting((Player) sender, numCopies)) {
+            return null;
         }
 
         return book;
@@ -1743,52 +1759,110 @@ public class BooksWithoutBorders extends JavaPlugin {
         sender.sendMessage(ChatColor.GREEN + "\"" + fname + "\" deleted successfully");
     }
 
-    protected void unsign(Player player) {
+    /**
-        BookMeta oldbook = (BookMeta) player.getItemInHand().getItemMeta();
+     * Unsigns the player's currently held book
-        ItemStack newbook = new ItemStack(Material.WRITABLE_BOOK);
+     * @param player <p>The player holding the book</p>
-        newbook.setItemMeta(oldbook);
+     * @param mainHand <p>Whether the player is holding the book in its main hand or its off hand</p>
+     */
+    protected void unSignHeldBook(Player player, boolean mainHand) {
+        //Get the old book
+        BookMeta oldBook;
+        if (mainHand) {
+            oldBook = (BookMeta) player.getInventory().getItemInMainHand().getItemMeta();
+        } else {
+            oldBook = (BookMeta) player.getInventory().getItemInOffHand().getItemMeta();
+        }
 
-        player.setItemInHand(newbook);
+        //UnSign the book
+        ItemStack newBook = new ItemStack(Material.WRITABLE_BOOK);
+        newBook.setItemMeta(oldBook);
+
+        if (mainHand) {
+            player.getInventory().setItemInMainHand(newBook);
+        } else {
+            player.getInventory().setItemInOffHand(newBook);
+        }
     }
 
     protected boolean BooksHavePrice() {
         return (bookPriceType != null && bookPriceQuantity > 0);
     }
 
-    protected boolean printBook(Player player, int numCopies) {
+    /**
+     * Makes the player pay for printing a given number of books
+     * @param player <p>The player printing the books</p>
+     * @param numCopies <p>The number of copies the player is trying to print</p>
+     * @return <p>True if the player cannot pay for the printing of the books</p>
+     */
+    protected boolean cannotPayForBookPrinting(Player player, int numCopies) {
+        //BookPriceQuantity: How many items are required to pay for each book
+        //BookPriceType: Which item is used to pay for the books. AIR = use economy
+        double cost = bookPriceQuantity * numCopies;
+        int itemCost = (int) cost;
+
         if (bookPriceType == Material.AIR) {
-            if ((BooksWithoutBorders.eco.getBalance(player.getName()) - (bookPriceQuantity * numCopies)) >= 0) {
+            return !payForBookPrintingEconomy(player, cost, numCopies);
-                BooksWithoutBorders.eco.withdrawPlayer(player.getName(), (bookPriceQuantity * numCopies));
+        } else {
-                player.sendMessage(ChatColor.GREEN + BooksWithoutBorders.eco.format(bookPriceQuantity * numCopies) + " withdrawn to create " + numCopies + " book(s)");
+            if (player.getInventory().contains(bookPriceType, itemCost)) {
-                player.sendMessage(ChatColor.GREEN + "New balance: " + BooksWithoutBorders.eco.format(BooksWithoutBorders.eco.getBalance(player.getName())));
+                payForBookPrintingItem(player, itemCost);
-                return true;
-            } else {
-                player.sendMessage(ChatColor.RED + BooksWithoutBorders.eco.format(bookPriceQuantity * numCopies) + " is required for this command!");
                 return false;
+            } else {
+                player.sendMessage(ChatColor.RED + String.valueOf(itemCost) + " " + bookPriceType.toString() +
+                        "(s) are required for this command!");
+                return true;
             }
-        } else if (player.getInventory().contains(bookPriceType, (int) bookPriceQuantity * numCopies)) {
-
-            int clearedAmount = 0, reqAmount = (int) bookPriceQuantity * numCopies;
-            while (clearedAmount != reqAmount) {
-                if (player.getInventory().getItem(player.getInventory().first(bookPriceType)).getAmount() <= reqAmount - clearedAmount) {
-                    clearedAmount += player.getInventory().getItem(player.getInventory().first(bookPriceType)).getAmount();
-                    player.getInventory().clear(player.getInventory().first(bookPriceType));
-                } else {
-                    clearedAmount = reqAmount;
-                    player.getInventory().getItem(player.getInventory().first(bookPriceType)).setAmount(player.getInventory().getItem(player.getInventory().first(bookPriceType)).getAmount() - (clearedAmount));
-                }
-            }
-            return true;
         }
-
-        player.sendMessage(ChatColor.RED + String.valueOf((int) bookPriceQuantity * numCopies) + " " + bookPriceType.toString() + "(s) are required for this command!");
-        return false;
     }
 
-    protected boolean printBook(Player player) {
+    /**
-        return printBook(player, 1);
+     * Takes payment for printing a number of books by withdrawing the correct item
+     * @param player <p>The player which needs to pay</p>
+     * @param itemCost <p>The number of items to pay</p>
+     */
+    private void payForBookPrintingItem(Player player, int itemCost) {
+        PlayerInventory playerInventory = player.getInventory();
+
+        int clearedAmount = 0;
+        while (clearedAmount < itemCost) {
+            int firstItemIndex = playerInventory.first(bookPriceType);
+            ItemStack firstItem = playerInventory.getItem(firstItemIndex);
+
+            if (Objects.requireNonNull(firstItem).getAmount() <= itemCost - clearedAmount) {
+                clearedAmount += firstItem.getAmount();
+                player.getInventory().clear(firstItemIndex);
+            } else {
+                clearedAmount = itemCost;
+                firstItem.setAmount(firstItem.getAmount() - (clearedAmount));
+            }
+        }
     }
 
+    /**
+     * Uses economy to take payment for printing a number of books
+     * @param player <p>The player which needs to pay</p>
+     * @param cost <p>The cost of the book printing</p>
+     * @param numCopies <p>The number of books the player is printing</p>
+     * @return <p>True if the player had the money and it has been withdrawn</p>
+     */
+    private boolean payForBookPrintingEconomy(Player player, double cost, int numCopies) {
+        Economy economy = BooksWithoutBorders.eco;
+        if ((economy.getBalance(player) - cost) >= 0) {
+            economy.withdrawPlayer(player, cost);
+            player.sendMessage(ChatColor.GREEN + economy.format(cost) + " withdrawn to create " + numCopies + " book(s)");
+            player.sendMessage(ChatColor.GREEN + "New balance: " + economy.format(economy.getBalance(player)));
+            return true;
+        } else {
+            player.sendMessage(ChatColor.RED + economy.format(cost) + " is required for this command!");
+            return false;
+        }
+    }
+
+    /**
+     * Checks whether the given player is the author of a given book
+     * @param player <p>The player to check</p>
+     * @param book <p>The book to check</p>
+     * @return <p>True if the player is the book's author</p>
+     */
     protected boolean isAuthor(Player player, BookMeta book) {
         String author = book.getAuthor();
         if (author != null && cleanString(player.getName()).equalsIgnoreCase(cleanString(author))) {