优化

web/src/utils/libraryTags.test.ts

@@ -11,6 +11,7 @@ import {
   filterLibrariesForTagging,
   normalizeLibraryTags,
   normalizeTagName,
+  reorderLibraryTags,
   resolveSelectedTagId,
   tagNameError,
 } from './libraryTags.ts'
@@ -49,10 +50,10 @@ check('tag tab keeps creation order', tabs[1].name === '动画' && tabs[2].name
 check('tag count ignores unavailable libraries', tabs[1].count === 1)
 
 check(
-  'filtering keeps tag order and drops unknown ids',
+  'filtering drops unknown ids and keeps input order',
   filterLibrariesByTag(libs, [{ name: '动画', library_ids: ['lib-c', 'missing', 'lib-a'] }], '动画')
     .map((lib) => lib.id)
-    .join(',') === 'lib-c,lib-a',
+    .join(',') === 'lib-a,lib-c',
 )
 check('全部 returns every library in original order', filterLibrariesByTag(libs, [], ALL_TAG_ID).length === 3)
 check('unknown tag yields no libraries', filterLibrariesByTag(libs, [], 'nope').length === 0)
@@ -135,4 +136,31 @@ check(
   tagNameError('动画', [{ name: '动画', library_ids: [] }], '动画') === '',
 )
 
+const reorderable = [
+  { name: '动画', library_ids: [] },
+  { name: '电影', library_ids: [] },
+  { name: '音乐', library_ids: [] },
+]
+check(
+  'reorder moves a tag to the requested slot',
+  reorderLibraryTags(reorderable, ['电影', '动画', '音乐']).map((tag) => tag.name).join(',') === '电影,动画,音乐',
+)
+check(
+  'reorder can move a tag to the front',
+  reorderLibraryTags(reorderable, ['音乐', '动画', '电影']).map((tag) => tag.name).join(',') === '音乐,动画,电影',
+)
+check(
+  'names missing from the order keep relative order at the end',
+  reorderLibraryTags(reorderable, ['电影']).map((tag) => tag.name).join(',') === '电影,动画,音乐',
+)
+check(
+  'empty order leaves tags untouched',
+  reorderLibraryTags(reorderable, []).map((tag) => tag.name).join(',') === '动画,电影,音乐',
+)
+check('reorder ignores extra unknown names', reorderLibraryTags(reorderable, ['不存在', '音乐']).map((tag) => tag.name).join(',') === '音乐,动画,电影')
+check(
+  'reordering with fewer than two tags is a no-op',
+  reorderLibraryTags([{ name: '动画', library_ids: [] }], []).map((tag) => tag.name).join(',') === '动画',
+)
+
 console.log('libraryTags.test.ts ok')

web/src/utils/libraryTags.ts

@@ -164,8 +164,9 @@ export function isLibraryInTag(tags: LibraryTag[], tagId: string, libraryId: str
 }
 
 /**
- * 按标签过滤媒体库：`tagId` 为「全部」时原样返回（保持原有置顶/手动排序），
- * 否则只保留该标签下的库，并保持标签里记录的顺序。
+ * 按标签过滤媒体库：`tagId` 为「全部」时原样返回。
+ * 只做成员筛选、保持输入顺序，展示顺序（置顶、排序下拉等）由调用方决定；
+ * 标签里记录的 library_ids 顺序只表示归属，不作为展示排序。
  */
 export function filterLibrariesByTag<T extends { id: string }>(
   libraries: T[],
@@ -173,15 +174,9 @@ export function filterLibrariesByTag<T extends { id: string }>(
   tagId: string,
 ): T[] {
   if (!tagId || tagId === ALL_TAG_ID) return libraries
-  const ids = tagLibraryIds(tags, tagId)
-  if (ids.length === 0) return []
-  const byId = new Map(libraries.map((lib) => [lib.id, lib]))
-  const out: T[] = []
-  for (const id of ids) {
-    const lib = byId.get(id)
-    if (lib) out.push(lib)
-  }
-  return out
+  const ids = new Set(tagLibraryIds(tags, tagId))
+  if (ids.size === 0) return []
+  return libraries.filter((lib) => ids.has(lib.id))
 }
 
 /** 生成标签栏模型：首项固定为「全部」，其后按标签顺序追加。 */
@@ -202,6 +197,22 @@ export function buildLibraryTagTabs(libraries: Library[], tags: LibraryTag[]): L
   return tabs
 }
 
+/**
+ * 按给定标签名顺序重排标签栏：`orderedNames` 是期望的标签名顺序（通常来自拖拽后的顺序）。
+ * 未出现在顺序里的标签（例如新建、旧数据并发写入）保持原相对顺序，追加到末尾，绝不丢失。
+ */
+export function reorderLibraryTags(tags: LibraryTag[], orderedNames: string[]): LibraryTag[] {
+  if (tags.length < 2) return tags
+  const rank = new Map(orderedNames.map((name, index) => [name, index]))
+  const ranked: LibraryTag[] = []
+  const rest: LibraryTag[] = []
+  for (const tag of tags) {
+    ;(rank.has(tag.name) ? ranked : rest).push(tag)
+  }
+  ranked.sort((a, b) => (rank.get(a.name) ?? 0) - (rank.get(b.name) ?? 0))
+  return [...ranked, ...rest]
+}
+
 /** 选中的标签是否仍存在；被删除或被过滤掉时回落到「全部」。 */
 export function resolveSelectedTagId(tags: LibraryTag[], selectedId: string): string {
   if (!selectedId || selectedId === ALL_TAG_ID) return ALL_TAG_ID