feat: Implement core API endpoints, database schema, ActivityPub federation, and initial user interface for the application.

src/lib/activitypub/actor.ts

@@ -0,0 +1,119 @@
+/**
+ * ActivityPub Actor Utilities
+ * 
+ * Handles the serialization of Synapsis users to ActivityPub Actor format.
+ * See: https://www.w3.org/TR/activitypub/#actor-objects
+ */
+
+import type { users } from '@/db/schema';
+
+type User = typeof users.$inferSelect;
+
+const ACTIVITY_STREAMS_CONTEXT = 'https://www.w3.org/ns/activitystreams';
+const SECURITY_CONTEXT = 'https://w3id.org/security/v1';
+
+export interface ActivityPubActor {
+    '@context': (string | object)[];
+    id: string;
+    type: 'Person';
+    preferredUsername: string;
+    name: string | null;
+    summary: string | null;
+    url: string;
+    inbox: string;
+    outbox: string;
+    followers: string;
+    following: string;
+    icon?: {
+        type: 'Image';
+        mediaType: string;
+        url: string;
+    };
+    image?: {
+        type: 'Image';
+        mediaType: string;
+        url: string;
+    };
+    publicKey: {
+        id: string;
+        owner: string;
+        publicKeyPem: string;
+    };
+    endpoints: {
+        sharedInbox: string;
+    };
+}
+
+/**
+ * Convert a Synapsis user to an ActivityPub Actor
+ */
+export function userToActor(user: User, nodeDomain: string): ActivityPubActor {
+    const actorUrl = `https://${nodeDomain}/users/${user.handle}`;
+
+    const actor: ActivityPubActor = {
+        '@context': [
+            ACTIVITY_STREAMS_CONTEXT,
+            SECURITY_CONTEXT,
+            {
+                'manuallyApprovesFollowers': 'as:manuallyApprovesFollowers',
+                'toot': 'http://joinmastodon.org/ns#',
+                'featured': {
+                    '@id': 'toot:featured',
+                    '@type': '@id',
+                },
+            },
+        ],
+        id: actorUrl,
+        type: 'Person',
+        preferredUsername: user.handle,
+        name: user.displayName,
+        summary: user.bio,
+        url: actorUrl,
+        inbox: `${actorUrl}/inbox`,
+        outbox: `${actorUrl}/outbox`,
+        followers: `${actorUrl}/followers`,
+        following: `${actorUrl}/following`,
+        publicKey: {
+            id: `${actorUrl}#main-key`,
+            owner: actorUrl,
+            publicKeyPem: user.publicKey,
+        },
+        endpoints: {
+            sharedInbox: `https://${nodeDomain}/inbox`,
+        },
+    };
+
+    // Add avatar if present
+    if (user.avatarUrl) {
+        actor.icon = {
+            type: 'Image',
+            mediaType: 'image/png', // TODO: detect actual type
+            url: user.avatarUrl,
+        };
+    }
+
+    // Add header if present
+    if (user.headerUrl) {
+        actor.image = {
+            type: 'Image',
+            mediaType: 'image/png',
+            url: user.headerUrl,
+        };
+    }
+
+    return actor;
+}
+
+/**
+ * Get the actor URL for a user
+ */
+export function getActorUrl(handle: string, nodeDomain: string): string {
+    return `https://${nodeDomain}/users/${handle}`;
+}
+
+/**
+ * Get the inbox URL for a user
+ */
+export function getInboxUrl(handle: string, nodeDomain: string): string {
+    return `https://${nodeDomain}/users/${handle}/inbox`;
+}