fully implement the mail command

src/main/java/emu/nebula/command/commands/MailCommand.java

@@ -1,20 +1,152 @@
 package emu.nebula.command.commands;
 
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
 import emu.nebula.command.Command;
 import emu.nebula.command.CommandArgs;
 import emu.nebula.command.CommandHandler;
 import emu.nebula.game.mail.GameMail;
+import emu.nebula.util.Utils;
 
-@Command(label = "mail", aliases = {"m"}, permission = "player.mail", requireTarget = true, desc = "/mail [content]. Sends the targeted player a system mail.")
+@Command(
+    label = "mail",
+    aliases = {"m"},
+    permission = "player.mail",
+    requireTarget = true,
+    desc = "/mail \"subject\" \"body\" [itemId xQty | itemId:qty ...]. Sends the targeted player a system mail."
+)
 public class MailCommand implements CommandHandler {
 
+    private static final Pattern QUOTED_TEXT = Pattern.compile("\"([^\"]*)\"");
+
     @Override
     public void execute(CommandArgs args) {
-        // Setup mail
+        var target = args.getTarget();
-        var mail = new GameMail("System", "Test", "This is a test mail");
+        if (target == null) {
+            args.sendMessage("Error: Targeted player not found or offline");
+            return;
+        }
+
+        String rawInput = args.getRaw() == null ? "" : args.getRaw().trim();
+        if (rawInput.isEmpty()) {
+            sendUsage(args);
+            return;
+        }
+
+        Matcher matcher = QUOTED_TEXT.matcher(rawInput);
+        if (!matcher.find()) {
+            sendUsage(args);
+            return;
+        }
+
+        String subject = matcher.group(1).trim();
+        if (!matcher.find()) {
+            args.sendMessage("Mail body must be wrapped in quotes after the subject.");
+            return;
+        }
+
+        String body = matcher.group(1).trim();
+        int attachmentStartIndex = matcher.end();
+
+        if (subject.isEmpty()) {
+            args.sendMessage("Mail subject cannot be empty.");
+            return;
+        }
+
+        if (body.isEmpty()) {
+            body = " "; // just for safety, so the client won't complain
+        }
+
+        String author = args.getSender() != null ? args.getSender().getName() : "System";
+        var mail = new GameMail(author, subject, body);
+
+        String attachmentSection = rawInput.length() > attachmentStartIndex
+                ? rawInput.substring(attachmentStartIndex).trim()
+                : "";
+
+        parseAttachments(attachmentSection, mail, args);
         
-        // Add mail
+        target.getMailbox().sendMail(mail);
-        args.getTarget().getMailbox().sendMail(mail);
+        args.sendMessage("Mail sent to " + target.getName() + " with subject \"" + subject + "\".");
     }
 
+    private void parseAttachments(String attachmentSection, GameMail mail, CommandArgs args) {
+        if (attachmentSection == null || attachmentSection.isBlank()) {
+            return;
+        }
+
+        Integer pendingItemId = null;
+        for (String token : attachmentSection.split("\\s+")) {
+            if (token.isBlank()) {
+                continue;
+            }
+
+            if (token.contains(":") || token.contains(",")) {
+                String[] split = token.split("[:,]", 2);
+                int itemId = Utils.parseSafeInt(split[0]);
+                int qty = split.length > 1 ? Utils.parseSafeInt(split[1]) : 1;
+                addAttachment(mail, args, itemId, qty);
+                pendingItemId = null;
+                continue;
+            }
+
+            if (token.startsWith("x") && token.length() > 1) {
+                if (pendingItemId == null) {
+                    args.sendMessage("Quantity token '" + token + "' must follow an item id.");
+                    continue;
+                }
+
+                int qty = Utils.parseSafeInt(token.substring(1));
+                addAttachment(mail, args, pendingItemId, qty);
+                pendingItemId = null;
+                continue;
+            }
+
+            if (isIntegerToken(token)) {
+                if (pendingItemId != null) {
+                    addAttachment(mail, args, pendingItemId, 1);
+                }
+
+                int itemId = Utils.parseSafeInt(token);
+                if (itemId <= 0) {
+                    args.sendMessage("Invalid item id '" + token + "'.");
+                    pendingItemId = null;
+                    continue;
+                }
+
+                pendingItemId = itemId;
+                continue;
+            }
+
+            args.sendMessage("Ignoring attachment token '" + token + "'.");
+        }
+
+        if (pendingItemId != null) {
+            addAttachment(mail, args, pendingItemId, 1);
+        }
+    }
+
+    private void addAttachment(GameMail mail, CommandArgs args, int itemId, int quantity) {
+        if (itemId <= 0) {
+            args.sendMessage("Item id must be positive.");
+            return;
+        }
+
+        int qty = Math.max(quantity, 1);
+        mail.addAttachment(itemId, qty);
+    }
+
+    private boolean isIntegerToken(String token) {
+        for (int i = 0; i < token.length(); i++) {
+            if (!Character.isDigit(token.charAt(i))) {
+                return false;
+            }
+        }
+        return !token.isEmpty();
+    }
+
+    private void sendUsage(CommandArgs args) {
+        args.sendMessage("Usage: /mail \"subject\" \"body\" [itemId xQty | itemId:qty ...]");
+    }
 }