Refactor: Store ICE candidates as JSON objects

- Simplify storage by storing entire RTCIceCandidateInit as JSON
- Remove individual sdp_mid and sdp_m_line_index columns
- More future-proof and maintainable approach
- Recreated ice_candidates table in D1

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/storage/d1.ts

@@ -1,4 +1,4 @@
-import { Storage, Offer, IceCandidate, CreateOfferRequest, TopicInfo } from './types.ts';
+import { Storage, Offer, IceCandidate, CreateOfferRequest, TopicInfo, RTCIceCandidateInit } from './types.ts';
 
 // Generate a UUID v4
 function generateUUID(): string {
@@ -58,9 +58,7 @@ export class D1Storage implements Storage {
         offer_id TEXT NOT NULL,
         peer_id TEXT NOT NULL,
         role TEXT NOT NULL CHECK(role IN ('offerer', 'answerer')),
-        candidate TEXT NOT NULL,
+        candidate TEXT NOT NULL, -- JSON: RTCIceCandidateInit object
-        sdp_mid TEXT,
-        sdp_m_line_index INTEGER,
         created_at INTEGER NOT NULL,
         FOREIGN KEY (offer_id) REFERENCES offers(id) ON DELETE CASCADE
       );
@@ -244,24 +242,18 @@ export class D1Storage implements Storage {
     offerId: string,
     peerId: string,
     role: 'offerer' | 'answerer',
-    candidates: Array<{
+    candidates: RTCIceCandidateInit[]
-      candidate: string;
-      sdpMid?: string | null;
-      sdpMLineIndex?: number | null;
-    }>
   ): Promise<number> {
     // D1 doesn't have transactions, so insert one by one
     for (const cand of candidates) {
       await this.db.prepare(`
-        INSERT INTO ice_candidates (offer_id, peer_id, role, candidate, sdp_mid, sdp_m_line_index, created_at)
+        INSERT INTO ice_candidates (offer_id, peer_id, role, candidate, created_at)
-        VALUES (?, ?, ?, ?, ?, ?, ?)
+        VALUES (?, ?, ?, ?, ?)
       `).bind(
         offerId,
         peerId,
         role,
-        cand.candidate,
+        JSON.stringify(cand), // Store full object as JSON
-        cand.sdpMid ?? null,
-        cand.sdpMLineIndex ?? null,
         Date.now()
       ).run();
     }
@@ -299,9 +291,7 @@ export class D1Storage implements Storage {
       offerId: row.offer_id,
       peerId: row.peer_id,
       role: row.role,
-      candidate: row.candidate,
+      candidate: JSON.parse(row.candidate), // Parse JSON back to object
-      sdpMid: row.sdp_mid,
-      sdpMLineIndex: row.sdp_m_line_index,
       createdAt: row.created_at,
     }));
   }

src/storage/sqlite.ts

@@ -1,6 +1,6 @@
 import Database from 'better-sqlite3';
 import { randomUUID } from 'crypto';
-import { Storage, Offer, IceCandidate, CreateOfferRequest, TopicInfo } from './types.ts';
+import { Storage, Offer, IceCandidate, CreateOfferRequest, TopicInfo, RTCIceCandidateInit } from './types.ts';
 
 /**
  * SQLite storage adapter for topic-based offer management
@@ -55,9 +55,7 @@ export class SQLiteStorage implements Storage {
         offer_id TEXT NOT NULL,
         peer_id TEXT NOT NULL,
         role TEXT NOT NULL CHECK(role IN ('offerer', 'answerer')),
-        candidate TEXT NOT NULL,
+        candidate TEXT NOT NULL, -- JSON: RTCIceCandidateInit object
-        sdp_mid TEXT,
-        sdp_m_line_index INTEGER,
         created_at INTEGER NOT NULL,
         FOREIGN KEY (offer_id) REFERENCES offers(id) ON DELETE CASCADE
       );
@@ -254,26 +252,20 @@ export class SQLiteStorage implements Storage {
     offerId: string,
     peerId: string,
     role: 'offerer' | 'answerer',
-    candidates: Array<{
+    candidates: RTCIceCandidateInit[]
-      candidate: string;
-      sdpMid?: string | null;
-      sdpMLineIndex?: number | null;
-    }>
   ): Promise<number> {
     const stmt = this.db.prepare(`
-      INSERT INTO ice_candidates (offer_id, peer_id, role, candidate, sdp_mid, sdp_m_line_index, created_at)
+      INSERT INTO ice_candidates (offer_id, peer_id, role, candidate, created_at)
-      VALUES (?, ?, ?, ?, ?, ?, ?)
+      VALUES (?, ?, ?, ?, ?)
     `);
 
-    const transaction = this.db.transaction((candidates: typeof candidates) => {
+    const transaction = this.db.transaction((candidates: RTCIceCandidateInit[]) => {
       for (const cand of candidates) {
         stmt.run(
           offerId,
           peerId,
           role,
-          cand.candidate,
+          JSON.stringify(cand), // Store full object as JSON
-          cand.sdpMid ?? null,
-          cand.sdpMLineIndex ?? null,
           Date.now()
         );
       }
@@ -310,9 +302,7 @@ export class SQLiteStorage implements Storage {
       offerId: row.offer_id,
       peerId: row.peer_id,
       role: row.role,
-      candidate: row.candidate,
+      candidate: JSON.parse(row.candidate), // Parse JSON back to object
-      sdpMid: row.sdp_mid,
-      sdpMLineIndex: row.sdp_m_line_index,
       createdAt: row.created_at,
     }));
   }

src/storage/types.ts

@@ -16,18 +16,27 @@ export interface Offer {
 
 /**
  * Represents an ICE candidate for WebRTC signaling
+ * Stores the complete RTCIceCandidateInit object
  */
 export interface IceCandidate {
   id: number;
   offerId: string;
   peerId: string;
   role: 'offerer' | 'answerer';
-  candidate: string;
+  candidate: RTCIceCandidateInit; // Full candidate object as JSON
-  sdpMid: string | null;
-  sdpMLineIndex: number | null;
   createdAt: number;
 }
 
+/**
+ * RTCIceCandidateInit interface for TypeScript environments without WebRTC
+ */
+export interface RTCIceCandidateInit {
+  candidate?: string;
+  sdpMid?: string | null;
+  sdpMLineIndex?: number | null;
+  usernameFragment?: string | null;
+}
+
 /**
  * Represents a topic with active peer count
  */
@@ -127,18 +136,14 @@ export interface Storage {
    * @param offerId Offer identifier
    * @param peerId Peer ID posting the candidates
    * @param role Role of the peer (offerer or answerer)
-   * @param candidates Array of ICE candidate objects
+   * @param candidates Array of RTCIceCandidateInit objects
    * @returns Number of candidates added
    */
   addIceCandidates(
     offerId: string,
     peerId: string,
     role: 'offerer' | 'answerer',
-    candidates: Array<{
+    candidates: RTCIceCandidateInit[]
-      candidate: string;
-      sdpMid?: string | null;
-      sdpMLineIndex?: number | null;
-    }>
   ): Promise<number>;
 
   /**