Update blog editor features

frontend/src/components/TableOfContents.tsx

@@ -0,0 +1,107 @@
+import { useEffect, useState } from 'react'
+import type { MouseEvent } from 'react'
+import { ListIcon } from 'lucide-react'
+import { slugifyFa, uniqueSlug } from '../utils/slug'
+
+export type TocItem = { id: string; text: string; level: 2 | 3 }
+
+/**
+ * استخراج فهرست مطالب از HTML ویرایشگر — تیترهای H2 و H3 شناسه لنگر می‌گیرند
+ * (با slugify و پشتیبانی فارسی) و HTML برگشتی همان است که باید رندر شود.
+ */
+export function extractToc(html: string): { items: TocItem[]; html: string } {
+  if (!html || typeof window === 'undefined') return { items: [], html }
+  const doc = new DOMParser().parseFromString(html, 'text/html')
+  const used = new Map<string, number>()
+  const items: TocItem[] = []
+
+  doc.body.querySelectorAll('h2, h3').forEach((el) => {
+    const text = (el.textContent ?? '').replace(/\s+/g, ' ').trim()
+    if (!text) return
+    const id = uniqueSlug(slugifyFa(text), used)
+    el.setAttribute('id', id)
+    items.push({ id, text, level: el.tagName === 'H3' ? 3 : 2 })
+  })
+
+  return { items, html: doc.body.innerHTML }
+}
+
+type TableOfContentsProps = {
+  items: TocItem[]
+  title?: string
+  className?: string
+}
+
+/** فهرست مطالب کلیک‌پذیر با هایلایت خودکار تیتر فعال (IntersectionObserver) */
+export function TableOfContents({ items, title = 'فهرست مطالب', className = '' }: TableOfContentsProps) {
+  const [activeId, setActiveId] = useState<string>(items[0]?.id ?? '')
+
+  useEffect(() => {
+    setActiveId(items[0]?.id ?? '')
+  }, [items])
+
+  useEffect(() => {
+    if (!items.length || typeof IntersectionObserver === 'undefined') return
+    const observer = new IntersectionObserver(
+      (entries) => {
+        const visible = entries
+          .filter((entry) => entry.isIntersecting)
+          .sort((a, b) => a.boundingClientRect.top - b.boundingClientRect.top)
+        const first = visible[0]?.target.id
+        if (first) setActiveId(first)
+      },
+      { rootMargin: '-15% 0px -70% 0px', threshold: [0, 1] },
+    )
+    items.forEach((item) => {
+      const el = document.getElementById(item.id)
+      if (el) observer.observe(el)
+    })
+    return () => observer.disconnect()
+  }, [items])
+
+  if (items.length === 0) return null
+
+  const go = (event: MouseEvent<HTMLButtonElement>, id: string) => {
+    event.preventDefault()
+    const el = document.getElementById(id)
+    if (!el) return
+    el.scrollIntoView({ behavior: 'smooth', block: 'start' })
+    window.history.replaceState(null, '', `#${id}`)
+  }
+
+  return (
+    <nav
+      aria-label="فهرست مطالب"
+      className={`rounded-2xl border border-white/10 bg-char/60 p-6 backdrop-blur-xl shadow-[0_20px_50px_rgba(0,0,0,0.35),inset_0_1px_1px_rgba(255,255,255,0.08)] ${className}`}
+    >
+      <p className="flex items-center gap-2 text-sm font-bold text-copper">
+        <ListIcon className="h-4 w-4" aria-hidden="true" />
+        {title}
+      </p>
+      <div className="mt-5 h-px w-12 bg-copper/50" aria-hidden="true" />
+      <ul className="mt-4 max-h-[60vh] space-y-0.5 overflow-y-auto border-r border-ivory/10 pr-3">
+        {items.map((item) => {
+          const isActive = item.id === activeId
+          return (
+            <li key={item.id}>
+              <button
+                type="button"
+                onClick={(event) => go(event, item.id)}
+                aria-current={isActive ? 'location' : undefined}
+                className={`block w-full text-right text-sm font-light leading-8 transition-colors duration-200 ease-lux ${
+                  item.level === 3 ? 'pr-4 text-[13px]' : ''
+                } ${
+                  isActive
+                    ? 'font-normal text-copper'
+                    : 'text-ivory/60 hover:text-copper'
+                }`}
+              >
+                {item.text}
+              </button>
+            </li>
+          )
+        })}
+      </ul>
+    </nav>
+  )
+}