show max message length in error message

public/language/en-GB/error.json

@@ -129,7 +129,7 @@
 	"chat-disabled": "Chat system disabled",
 	"too-many-messages": "You have sent too many messages, please wait awhile.",
 	"invalid-chat-message": "Invalid chat message",
-	"chat-message-too-long": "Chat message is too long",
+	"chat-message-too-long": "Chat messages can not be longer than %1 characters.",
 	"cant-edit-chat-message": "You are not allowed to edit this message",
 	"cant-remove-last-user": "You can't remove the last user",
 	"cant-delete-chat-message": "You are not allowed to delete this message",

public/src/client/chats/messages.js

@@ -9,7 +9,7 @@ define('forum/chats/messages', ['components', 'sounds', 'translator'], function
 		var mid = inputEl.attr('data-mid');
 
 		if (msg.length > ajaxify.data.maximumChatMessageLength) {
-			return app.alertError('[[error:chat-message-too-long]]');
+			return app.alertError('[[error:chat-message-too-long,' + ajaxify.data.maximumChatMessageLength + ']]');
 		}
 
 		if (!msg.length) {

src/messaging/create.js

@@ -30,9 +30,11 @@ module.exports = function (Messaging) {
 		if (!content) {
 			return callback(new Error('[[error:invalid-chat-message]]'));
 		}
+		content = String(content);
 
-		if (content.length > (meta.config.maximumChatMessageLength || 1000)) {
+		var maximumChatMessageLength = (meta.config.maximumChatMessageLength || 1000);
-			return callback(new Error('[[error:chat-message-too-long]]'));
+		if (content.length > maximumChatMessageLength) {
+			return callback(new Error('[[error:chat-message-too-long, ' + maximumChatMessageLength + ']]'));
 		}
 		callback();
 	};
@@ -52,7 +54,7 @@ module.exports = function (Messaging) {
 			function (_mid, next) {
 				mid = _mid;
 				message = {
-					content: content,
+					content: String(content),
 					timestamp: timestamp,
 					fromuid: fromuid,
 					roomId: roomId,