Show specific error message when trying to create a channel named like an archived one

i18n/en.i18n.json

@@ -134,6 +134,7 @@
   "Disable_New_Message_Notification" : "Disable New Message Notification",
   "Disable_New_Room_Notification" : "Disable New Room Notification",
   "Drop_to_upload_file" : "Drop to upload file",
+  "Duplicate_archived_channel_name" : "An archived Channel with name '%s' exists",
   "Duplicate_channel_name" : "A Channel with name '%s' exists",
   "Duplicate_private_group_name" : "A Private Group with name '%s' exists",
   "E-mail" : "E-mail",

packages/rocketchat-ui-sidenav/side-nav/createChannelFlex.coffee

@@ -90,6 +90,9 @@ Template.createChannelFlex.events
 					if err.error is 'duplicate-name'
 						instance.error.set({ duplicate: true })
 						return
+					if err.error is 'archived-duplicate-name'
+						instance.error.set({ archivedduplicate: true })
+						return
 					else
 						return toastr.error err.reason
 

packages/rocketchat-ui-sidenav/side-nav/createChannelFlex.html

@@ -40,6 +40,12 @@
 					{{{_ "Duplicate_channel_name" roomName}}}
 				</div>
 			{{/if}}
+			{{#if error.archivedduplicate}}
+				<div class="input-error">
+					<strong>{{_ "Oops!"}}</strong>
+					{{{_ "Duplicate_archived_channel_name" roomName}}}
+				</div>
+			{{/if}}
 			<div class="input-submit">
 				<button class="button clean primary save-channel">{{_ "Save" }}</button>
 				<button class="button clean cancel-channel">{{_ "Cancel" }}</button>

server/methods/createChannel.coffee

@@ -23,7 +23,10 @@ Meteor.methods
 
 		# avoid duplicate names
 		if RocketChat.models.Rooms.findOneByName name
-			throw new Meteor.Error 'duplicate-name'
+			if RocketChat.models.Rooms.findOneByName(name).archived
+				throw new Meteor.Error 'archived-duplicate-name'
+			else
+				throw new Meteor.Error 'duplicate-name'
 
 		# name = s.slugify name