From 5244573936e7cf9669063c54fea8fc3b09754fcc Mon Sep 17 00:00:00 2001
From: Igor Sikachyna <igor.sikachyna@ultra.io>
Date: Thu, 9 May 2024 08:07:56 -0400
Subject: [PATCH] BLOCK-2247 - Give error if user tries to link account twice
 (#33)

---
 src/services/database/user.ts         |  4 ++--
 src/services/discord/commands/link.ts | 10 ++++++++++
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/src/services/database/user.ts b/src/services/database/user.ts
index f5ab6a7..1f3fdbe 100644
--- a/src/services/database/user.ts
+++ b/src/services/database/user.ts
@@ -73,7 +73,7 @@ export async function removeUser(discord: string): Promise<I.Response<dDiscordUs
 }
 
 /**
- * Return a database doucment for a user.
+ * Return a database document for a user.
  *
  * Can use either the discord, or blockchain id for lookup.
  *
@@ -103,7 +103,7 @@ export async function getUser(
     });
 
     if (user === null || typeof user === 'undefined') {
-        return { status: false, data: 'user is already linked with a discord or blockchain id' };
+        return { status: false, data: 'discord user does not exist in the database' };
     }
 
     return { status: true, data: user };
diff --git a/src/services/discord/commands/link.ts b/src/services/discord/commands/link.ts
index f8f897c..6f75322 100644
--- a/src/services/discord/commands/link.ts
+++ b/src/services/discord/commands/link.ts
@@ -2,6 +2,7 @@ import { ActionRowBuilder, ButtonBuilder, ButtonStyle, Interaction, SlashCommand
 import { Endpoints } from '../../../types/endpointEnum';
 import * as Services from '../..';
 import * as Utility from '../../../utility';
+import { getUser } from '../../../services/database/user';
 
 const commandName = 'link';
 const commandDescription = 'Link up with your Ultra Blockchain ID';
@@ -63,6 +64,15 @@ async function handleInteraction(interaction: Interaction) {
         });
     }
 
+    // TODO: allow multiple links to work properly
+    const discordUserDocument = await getUser(interaction.user.id);
+    if (discordUserDocument.status) {
+        return interaction.reply({
+            content: 'You have already linked some other blockchain account to your Discord account. Unlink existing link first.',
+            ephemeral: true, // Makes responses 'only you can see this'
+        });
+    }
+
     const originalMessage = `${interaction.user.id} is linking their blockchain id to this service. By signing this message this confirms identification`;
     const messageRequest = Services.messageProvider.generate({
         discordUser: interaction.user.id,