fix: keep selection consistent with visible assets

src/platform/assets/composables/useAssetSelection.test.ts

@@ -0,0 +1,48 @@
+import { createPinia, setActivePinia } from 'pinia'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import { ref } from 'vue'
+
+import type { AssetItem } from '@/platform/assets/schemas/assetSchema'
+
+import { useAssetSelection } from './useAssetSelection'
+import { useAssetSelectionStore } from './useAssetSelectionStore'
+
+vi.mock('@vueuse/core', () => ({
+  useKeyModifier: vi.fn(() => ref(false))
+}))
+
+describe('useAssetSelection', () => {
+  beforeEach(() => {
+    setActivePinia(createPinia())
+  })
+
+  it('prunes selection to visible assets', () => {
+    const selection = useAssetSelection()
+    const store = useAssetSelectionStore()
+    const assets: AssetItem[] = [
+      { id: 'a', name: 'a.png', tags: [] },
+      { id: 'b', name: 'b.png', tags: [] }
+    ]
+
+    store.setSelection(['a', 'b'])
+    store.setLastSelectedIndex(1)
+
+    selection.reconcileSelection([assets[1]])
+
+    expect(Array.from(store.selectedAssetIds)).toEqual(['b'])
+    expect(store.lastSelectedIndex).toBe(-1)
+  })
+
+  it('clears selection when no visible assets remain', () => {
+    const selection = useAssetSelection()
+    const store = useAssetSelectionStore()
+
+    store.setSelection(['a'])
+    store.setLastSelectedIndex(0)
+
+    selection.reconcileSelection([])
+
+    expect(store.selectedAssetIds.size).toBe(0)
+    expect(store.lastSelectedIndex).toBe(-1)
+  })
+})