From b46442bd9dd74633410e14e1f27a698f31bb85d0 Mon Sep 17 00:00:00 2001
From: Xiaohan-Tian <157918347+Xiaohan-Tian@users.noreply.github.com>
Date: Thu, 22 Jan 2026 19:10:01 -0800
Subject: [PATCH] feat: added upgradeToV3 upgrader

---
 src/core/KGProject.ts                         |  2 +-
 .../project-upgrader/KGProjectUpgrader.ts     |  5 ++++
 src/core/project-upgrader/upgradeToV3.ts      | 26 +++++++++++++++++++
 src/test/utils/mock-data.ts                   |  2 +-
 4 files changed, 33 insertions(+), 2 deletions(-)
 create mode 100644 src/core/project-upgrader/upgradeToV3.ts

diff --git a/src/core/KGProject.ts b/src/core/KGProject.ts
index 76a24bd..233fc2f 100644
--- a/src/core/KGProject.ts
+++ b/src/core/KGProject.ts
@@ -47,7 +47,7 @@ export class KGProject {
   @WithDefault(0)
   private projectStructureVersion: number = 0;
 
-  public static readonly CURRENT_PROJECT_STRUCTURE_VERSION: number = 2;
+  public static readonly CURRENT_PROJECT_STRUCTURE_VERSION: number = 3;
   
   @Expose()
   @Type(() => KGTrack, {
diff --git a/src/core/project-upgrader/KGProjectUpgrader.ts b/src/core/project-upgrader/KGProjectUpgrader.ts
index 048d7dd..d0f3bfa 100644
--- a/src/core/project-upgrader/KGProjectUpgrader.ts
+++ b/src/core/project-upgrader/KGProjectUpgrader.ts
@@ -1,6 +1,7 @@
 import { KGProject } from '../KGProject';
 import { upgradeToV1 } from './upgradeToV1';
 import { upgradeToV2 } from './upgradeToV2';
+import { upgradeToV3 } from './upgradeToV3';
 
 /**
  * Upgrade the given project to the latest structure version, one version at a time.
@@ -28,6 +29,10 @@ export function upgradeProjectToLatest(project: KGProject): KGProject {
         workingProject = upgradeToV2(workingProject);
         break;
       }
+      case 3: {
+        workingProject = upgradeToV3(workingProject);
+        break;
+      }
       default: {
         // If an upgrader is missing, throw to prevent loading incompatible structures
         throw new Error(`No upgrader found for project structure version ${nextVersion}`);
diff --git a/src/core/project-upgrader/upgradeToV3.ts b/src/core/project-upgrader/upgradeToV3.ts
new file mode 100644
index 0000000..07dbf35
--- /dev/null
+++ b/src/core/project-upgrader/upgradeToV3.ts
@@ -0,0 +1,26 @@
+import { KGProject } from '../KGProject';
+
+/**
+ * Upgrade a project from structure version 2 to 3.
+ * Adds the isLooping and loopingRange fields with default values.
+ */
+export function upgradeToV3(project: KGProject): KGProject {
+  try {
+    // Set default isLooping to false if not already set
+    const currentIsLooping = project.getIsLooping?.();
+    if (currentIsLooping === undefined) {
+      project.setIsLooping(false);
+    }
+
+    // Set default loopingRange to [0, 0] if not already set
+    const currentLoopingRange = project.getLoopingRange?.();
+    if (!currentLoopingRange) {
+      project.setLoopingRange([0, 0]);
+    }
+  } finally {
+    // Always set the project structure version to 3 to mark migration complete
+    project.setProjectStructureVersion(3);
+  }
+
+  return project;
+}
diff --git a/src/test/utils/mock-data.ts b/src/test/utils/mock-data.ts
index bf3062f..c7607e3 100644
--- a/src/test/utils/mock-data.ts
+++ b/src/test/utils/mock-data.ts
@@ -124,7 +124,7 @@ export const createMockProject = (overrides: Partial<{
     false, // isLooping
     [0, 0], // loopingRange
     defaults.tracks, // tracks
-    1 // projectStructureVersion
+    3 // projectStructureVersion
   )
   
   return project