fix: restore complete admin feature dependencies

src/lib/admin-helpers.ts

@@ -0,0 +1,55 @@
+import type { ListParams } from '@/types'
+
+export const PER_PAGE_OPTIONS = [10, 20, 50] as const
+export const DEFAULT_PER_PAGE = 20
+
+export function parseListParams(searchParams: URLSearchParams): ListParams {
+  const search = searchParams.get('search') || ''
+  const perPage = Math.min(
+    Math.max(parseInt(searchParams.get('perPage') || String(DEFAULT_PER_PAGE), 10), 1),
+    100,
+  )
+  const page = Math.max(parseInt(searchParams.get('page') || '1', 10), 1)
+  const sort = searchParams.get('sort') || undefined
+  const order = (searchParams.get('order') === 'asc' ? 'asc' : 'desc') as 'asc' | 'desc'
+
+  return { search, perPage, page, sort, order }
+}
+
+export function calcPagination(total: number, page: number, perPage: number) {
+  const lastPage = Math.max(Math.ceil(total / perPage), 1)
+  return {
+    total,
+    page: Math.min(page, lastPage),
+    perPage,
+    lastPage,
+    offset: (Math.min(page, lastPage) - 1) * perPage,
+  }
+}
+
+/** Generate CSV content from rows */
+export function generateCsv(
+  rows: Record<string, unknown>[],
+  columns: { key: string; label: string }[],
+): string {
+  const BOM = '\uFEFF'
+  const header = columns.map((c) => escapeCsv(c.label)).join(',')
+  const body = rows
+    .map((row) => columns.map((c) => escapeCsv(String(row[c.key] ?? ''))).join(','))
+    .join('\n')
+
+  return `${BOM + header}\n${body}`
+}
+
+function escapeCsv(value: string): string {
+  if (value.includes(',') || value.includes('"') || value.includes('\n')) {
+    return `"${value.replace(/"/g, '""')}"`
+  }
+  return value
+}
+
+export function formatTimestamp(ts: number): string {
+  if (!ts) return 'N/A'
+  return new Date(ts * 1000).toLocaleString()
+}
+