1 files changed, 123 insertions, 0 deletions

diff --git a/src/server/repositories/sync.ts b/src/server/repositories/sync.ts
index 59a195a..188bd1b 100644
--- a/src/server/repositories/sync.ts
+++ b/src/server/repositories/sync.ts
@@ -9,6 +9,7 @@ import {
 	noteTypes,
 	reviewLogs,
 } from "../db/schema.js";
+import { type CrdtEntityTypeValue, crdtDocuments } from "../db/schema-crdt.js";
 import type {
 	Card,
 	Deck,
@@ -20,6 +21,20 @@ import type {
 } from "./types.js";
 
 /**
+ * CRDT sync payload for conflict-free synchronization
+ */
+export interface CrdtSyncPayload {
+	/** Document ID in format entityType:entityId */
+	documentId: string;
+	/** Entity type */
+	entityType: CrdtEntityTypeValue;
+	/** Entity ID */
+	entityId: string;
+	/** Base64-encoded CRDT binary */
+	binary: string;
+}
+
+/**
  * Sync data types for push/pull operations
  */
 export interface SyncPushData {
@@ -30,6 +45,8 @@ export interface SyncPushData {
 	noteFieldTypes: SyncNoteFieldTypeData[];
 	notes: SyncNoteData[];
 	noteFieldValues: SyncNoteFieldValueData[];
+	/** CRDT document changes for conflict-free sync */
+	crdtChanges?: CrdtSyncPayload[];
 }
 
 export interface SyncDeckData {
@@ -122,6 +139,12 @@ export interface SyncPushResult {
 	noteFieldTypes: { id: string; syncVersion: number }[];
 	notes: { id: string; syncVersion: number }[];
 	noteFieldValues: { id: string; syncVersion: number }[];
+	/** CRDT documents that were stored/merged */
+	crdtChanges: {
+		entityType: CrdtEntityTypeValue;
+		entityId: string;
+		syncVersion: number;
+	}[];
 	conflicts: {
 		decks: string[];
 		cards: string[];
@@ -144,6 +167,8 @@ export interface SyncPullResult {
 	noteFieldTypes: NoteFieldType[];
 	notes: Note[];
 	noteFieldValues: NoteFieldValue[];
+	/** CRDT document changes for conflict-free sync */
+	crdtChanges: CrdtSyncPayload[];
 	currentSyncVersion: number;
 }
 
@@ -165,6 +190,7 @@ export const syncRepository: SyncRepository = {
 			noteFieldTypes: [],
 			notes: [],
 			noteFieldValues: [],
+			crdtChanges: [],
 			conflicts: {
 				decks: [],
 				cards: [],
@@ -768,6 +794,78 @@ export const syncRepository: SyncRepository = {
 			}
 		}
 
+		// Process CRDT changes
+		if (data.crdtChanges && data.crdtChanges.length > 0) {
+			for (const crdtChange of data.crdtChanges) {
+				// Check if document exists
+				const existing = await db
+					.select({
+						id: crdtDocuments.id,
+						syncVersion: crdtDocuments.syncVersion,
+					})
+					.from(crdtDocuments)
+					.where(
+						and(
+							eq(crdtDocuments.userId, userId),
+							eq(crdtDocuments.entityType, crdtChange.entityType),
+							eq(crdtDocuments.entityId, crdtChange.entityId),
+						),
+					);
+
+				if (existing.length === 0) {
+					// New document - insert
+					const [inserted] = await db
+						.insert(crdtDocuments)
+						.values({
+							userId,
+							entityType: crdtChange.entityType,
+							entityId: crdtChange.entityId,
+							binary: crdtChange.binary,
+							syncVersion: 1,
+						})
+						.returning({
+							syncVersion: crdtDocuments.syncVersion,
+						});
+
+					if (inserted) {
+						result.crdtChanges.push({
+							entityType: crdtChange.entityType as CrdtEntityTypeValue,
+							entityId: crdtChange.entityId,
+							syncVersion: inserted.syncVersion,
+						});
+					}
+				} else {
+					// Existing document - update (store new binary, merge happens on client)
+					// For now, we just store the latest binary. Future: server-side Automerge merge
+					const [updated] = await db
+						.update(crdtDocuments)
+						.set({
+							binary: crdtChange.binary,
+							updatedAt: new Date(),
+							syncVersion: sql`${crdtDocuments.syncVersion} + 1`,
+						})
+						.where(
+							and(
+								eq(crdtDocuments.userId, userId),
+								eq(crdtDocuments.entityType, crdtChange.entityType),
+								eq(crdtDocuments.entityId, crdtChange.entityId),
+							),
+						)
+						.returning({
+							syncVersion: crdtDocuments.syncVersion,
+						});
+
+					if (updated) {
+						result.crdtChanges.push({
+							entityType: crdtChange.entityType as CrdtEntityTypeValue,
+							entityId: crdtChange.entityId,
+							syncVersion: updated.syncVersion,
+						});
+					}
+				}
+			}
+		}
+
 		return result;
 	},
 
@@ -882,6 +980,25 @@ export const syncRepository: SyncRepository = {
 			);
 		}
 
+		// Get all CRDT documents for user with syncVersion > lastSyncVersion
+		const pulledCrdtDocs = await db
+			.select()
+			.from(crdtDocuments)
+			.where(
+				and(
+					eq(crdtDocuments.userId, userId),
+					gt(crdtDocuments.syncVersion, lastSyncVersion),
+				),
+			);
+
+		// Convert CRDT documents to sync payload format
+		const pulledCrdtChanges: CrdtSyncPayload[] = pulledCrdtDocs.map((doc) => ({
+			documentId: `${doc.entityType}:${doc.entityId}`,
+			entityType: doc.entityType as CrdtEntityTypeValue,
+			entityId: doc.entityId,
+			binary: doc.binary,
+		}));
+
 		// Calculate current max sync version across all entities
 		let currentSyncVersion = lastSyncVersion;
 
@@ -920,6 +1037,11 @@ export const syncRepository: SyncRepository = {
 				currentSyncVersion = fieldValue.syncVersion;
 			}
 		}
+		for (const crdtDoc of pulledCrdtDocs) {
+			if (crdtDoc.syncVersion > currentSyncVersion) {
+				currentSyncVersion = crdtDoc.syncVersion;
+			}
+		}
 
 		return {
 			decks: pulledDecks,
@@ -929,6 +1051,7 @@ export const syncRepository: SyncRepository = {
 			noteFieldTypes: pulledNoteFieldTypes,
 			notes: pulledNotes,
 			noteFieldValues: pulledNoteFieldValues,
+			crdtChanges: pulledCrdtChanges,
 			currentSyncVersion,
 		};
 	},