feat: blog section

lib/blog-utils.ts

@@ -0,0 +1,96 @@
+import {
+  discoverBlocks,
+  mergeHeadingIdsIntoContentSegments,
+  type ContentSegment,
+} from "@/lib/blog-blocks";
+
+export type { ContentSegment } from "@/lib/blog-blocks";
+
+/**
+ * Creates a URL-safe slug from heading text (strip HTML, normalize, Persian-friendly).
+ */
+function slugify(text: string): string {
+  const stripped = text.replace(/<[^>]*>/g, "").trim();
+  return stripped
+    .replace(/\s+/g, "-")
+    .replace(/[^\p{L}\p{N}-]/gu, "")
+    .replace(/-+/g, "-")
+    .replace(/^-|-$/g, "")
+    .toLowerCase() || "section";
+}
+
+export interface TocItem {
+  id: string;
+  text: string;
+  level: number; // 2 = h2, 3 = h3, 4 = h4
+}
+
+const HEADING_REGEX = /<(h[234])[^>]*>([\s\S]*?)<\/\1>/gi;
+const usedIds = new Map<string, number>();
+
+function ensureUniqueId(baseId: string): string {
+  const count = usedIds.get(baseId) ?? 0;
+  usedIds.set(baseId, count + 1);
+  return count === 0 ? baseId : `${baseId}-${count}`;
+}
+
+/**
+ * پارس محتوا: ابتدا بلاک‌ها کشف و به JSON تبدیل می‌شوند (blog-blocks)،
+ * سپس id سرنویس‌ها تزریق می‌شود و سگمنت‌های نهایی برای رندر برمی‌گردند.
+ */
+export function parseContentHeadings(html: string): {
+  contentWithIds: string;
+  toc: TocItem[];
+  segments: ContentSegment[];
+} {
+  const { htmlWithPlaceholders, segments: rawSegments } = discoverBlocks(html);
+
+  usedIds.clear();
+  const toc: TocItem[] = [];
+  let lastIndex = 0;
+  let match: RegExpExecArray | null;
+  const parts: string[] = [];
+  const regex = new RegExp(HEADING_REGEX.source, "gi");
+
+  while ((match = regex.exec(htmlWithPlaceholders)) !== null) {
+    const [fullMatch, tag, inner] = match;
+    const level = parseInt(tag.charAt(1), 10) as 2 | 3 | 4;
+    const text = inner.replace(/<[^>]*>/g, "").trim();
+    const baseId = slugify(text);
+    const id = ensureUniqueId(baseId);
+
+    toc.push({ id, text, level });
+
+    const openTag = fullMatch.slice(0, fullMatch.indexOf(">") + 1);
+    const hasId = /^\s*<h[234][^>]*\bid\s*=/i.test(openTag);
+    const newOpenTag = hasId
+      ? openTag
+      : openTag.replace(/^(<\s*h[234])(\s|>)/i, `$1 id="${id}"$2`);
+
+    parts.push(htmlWithPlaceholders.slice(lastIndex, match.index));
+    parts.push(newOpenTag + inner + `</${tag}>`);
+    lastIndex = regex.lastIndex;
+  }
+
+  parts.push(htmlWithPlaceholders.slice(lastIndex));
+  const contentWithIds = parts.join("");
+  const segments = mergeHeadingIdsIntoContentSegments(
+    contentWithIds,
+    rawSegments
+  );
+
+  return { contentWithIds, toc, segments };
+}
+
+/** Average reading speed in words per minute (Persian/English mix). */
+const WPM = 200;
+
+/**
+ * Estimates reading time in minutes from HTML content.
+ */
+export function getReadingTimeMinutes(html: string): number {
+  const text = html.replace(/<[^>]*>/g, " ").replace(/\s+/g, " ").trim();
+  const wordCount = text.split(/\s+/).filter(Boolean).length;
+  return Math.max(1, Math.ceil(wordCount / WPM));
+}
+