Initial Commit

shared/utils/mentions.ts

@@ -0,0 +1,37 @@
+export interface MentionUser {
+  id: number
+  name: string
+  color: string | null
+}
+
+export function activeMention(text: string, caret: number) {
+  const before = text.slice(0, caret)
+  const start = before.lastIndexOf('@')
+  if (start < 0 || (start > 0 && !/[\s([{]/.test(before[start - 1]!))) return null
+  const query = before.slice(start + 1)
+  if (query.length > 50 || /[\r\n@]/.test(query)) return null
+  return { start, end: caret, query }
+}
+
+export function mentionParts(text: string, users: MentionUser[]) {
+  const names = [...users].sort((a, b) => b.name.length - a.name.length)
+  const parts: { text: string, user?: MentionUser }[] = []
+  let last = 0
+  for (let i = 0; i < text.length; i++) {
+    if (text[i] !== '@' || (i > 0 && !/[\s([{]/.test(text[i - 1]!))) continue
+    const user = names.find(u => text.slice(i + 1, i + 1 + u.name.length).toLowerCase() === u.name.toLowerCase()
+      && !/[\p{L}\p{N}_-]/u.test(text[i + 1 + u.name.length] ?? ''))
+    if (!user) continue
+    if (i > last) parts.push({ text: text.slice(last, i) })
+    last = i + 1 + user.name.length
+    parts.push({ text: text.slice(i, last), user })
+    i = last - 1
+  }
+  if (last < text.length) parts.push({ text: text.slice(last) })
+  return parts
+}
+
+export function mentionedUserIds(content: string, users: MentionUser[]) {
+  return new Set(content.split(/https?:\/\/[^\s<>"']+/g)
+    .flatMap(text => mentionParts(text, users).flatMap(part => part.user ? [part.user.id] : [])))
+}