Why am I so anal about my types

src/app.d.ts

@@ -26,12 +26,21 @@ declare global {
 
     type serviceType = 'jellyfin' | 'youtube-music'
 
-    interface BaseConnection {
+    type Service = Jellyfin.Service | YouTubeMusic.Service
+
+    type Tokens<T> = T extends Jellyfin.Service ? Jellyfin.Tokens : T extends YouTubeMusic.Service ? YouTubeMusic.Tokens : {}
+
+    // type ServiceTokenPair = [Jellyfin.Service, Jellyfin.Tokens] | [YouTubeMusic.Service, YouTubeMusic.Tokens]
+
+    interface BaseConnection<T> {
         id: string
         userId: string
-        type: serviceType
+        type: T extends Jellyfin.Service ? 'jellyfin' : T extends YouTubeMusic.Service ? 'youtube-music' : serviceType
+        service: T extends undefined ? Service : T
     }
 
+    type Connection<T extends Service = undefined> = BaseConnection<T> & Tokens<T>
+
     // These Schemas should only contain general info data that is necessary for data fetching purposes.
     // They are NOT meant to be stores for large amounts of data, i.e. Don't include the data for every single song the Playlist type.
     // Big data should be fetched as needed in the app, these exist to ensure that the info necessary to fetch that data is there.
@@ -85,19 +94,17 @@ declare global {
         // The jellyfin API will not always return the data it says it will, for example /Users/AuthenticateByName says it will
         // retrun the ServerName, it wont. This must be fetched from /System/Info.
         // So, ONLY DEFINE THE INTERFACES FOR DATA THAT IS GARUNTEED TO BE RETURNED (unless the data value itself is inherently optional)
-        interface Connection<T = undefined> extends BaseConnection {
+        interface Service {
-            type: 'jellyfin'
+            userId: string
-            jellyfinUserId: string
             urlOrigin: string
-            accessToken: string
-            info?: T
-        }
-
-        interface ConnectionInfo {
             username?: string
             serverName?: string
         }
 
+        interface Tokens {
+            accessToken: string
+        }
+
         interface User {
             Name: string
             Id: string
@@ -164,17 +171,17 @@ declare global {
     }
 
     namespace YouTubeMusic {
-        interface Connection<T = undefined> extends BaseConnection {
+        interface Service {
-            type: 'youtube-music'
+            userId: string
-            youtubeUserId: string
-            accessToken: string
-            info?: T
-        }
-
-        interface ConnectionInfo {
             username?: string
             profilePicture?: string
         }
+
+        interface Tokens {
+            accessToken: string
+            refreshToken: string
+            expiry: number
+        }
     }
 }
 

src/lib/server/users.ts

@@ -12,6 +12,7 @@ const initUsersTable = `CREATE TABLE IF NOT EXISTS Users(
 const initConnectionsTable = `CREATE TABLE IF NOT EXISTS Connections(
     id VARCHAR(36) PRIMARY KEY,
     userId VARCHAR(36) NOT NULL,
+    type VARCHAR(36) NOT NULL,
     service TEXT NOT NULL,
     accessToken TEXT NOT NULL,
     refreshToken TEXT,
@@ -23,6 +24,7 @@ db.exec(initUsersTable), db.exec(initConnectionsTable)
 interface ConnectionsTableSchema {
     id: string
     userId: string
+    type: string
     service: string
     accessToken: string
     refreshToken?: string
@@ -71,17 +73,19 @@ export class Connections {
         return connections
     }
 
-    static addConnection = (userId: string, service: Service, accessToken: string, refreshToken?: string, expiry?: number): Connection => {
+    static addConnection = (userId: string, service: Service, accessToken?: string, refreshToken?: string, expiry?: number): Connection => {
         const connectionId = generateUUID()
-        const ytConnection: YouTubeMusic.Connection = {
+        const test: Connection = {
             id: 'test',
             userId: 'test',
-            youtubeUserId: 'test',
+            type: 'jellyfin',
-            type: 'youtube-music',
+            service: {
+                userId: 'test',
+                urlOrigin: 'test',
+            },
             accessToken: 'test',
         }
-        const test = this.insertConnection(ytConnection)
+        // if (!isValidURL(service.urlOrigin)) throw new Error('Service does not have valid url')
-        if (!isValidURL(service.urlOrigin)) throw new Error('Service does not have valid url')
         db.prepare('INSERT INTO Connections(id, userId, service, accessToken, refreshToken, expiry) VALUES(?, ?, ?, ?, ?, ?)').run(connectionId, userId, JSON.stringify(service), accessToken, refreshToken, expiry)
         return this.getConnection(connectionId)
     }