feat: improve markdown rendering, artifact file preview, and public scheduled task page

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend-web/src/core/utils/markdown.ts

@@ -1,10 +1,127 @@
-export function extractTitleFromMarkdown(markdown: string) {
-  if (markdown.startsWith("# ")) {
-    let title = markdown.split("\n")[0]!.trim();
-    if (title.startsWith("# ")) {
-      title = title.slice(2).trim();
+export function extractTitleFromMarkdown(markdown: string) {
+  if (markdown.startsWith("# ")) {
+    let title = markdown.split("\n")[0]!.trim();
+    if (title.startsWith("# ")) {
+      title = title.slice(2).trim();
     }
     return title;
-  }
-  return undefined;
-}
+  }
+  return undefined;
+}
+
+export type MarkdownHeadingAnchor = {
+  level: number;
+  text: string;
+  id: string;
+};
+
+export type MarkdownAnchorResolver = {
+  headings: MarkdownHeadingAnchor[];
+  getHeadingId: (level: number, text: string) => string | undefined;
+  resolveHref: (href: string | undefined, label?: string) => string | null | undefined;
+};
+
+const HEADING_RE = /^(#{1,6})\s+(.+?)\s*#*\s*$/;
+const PROTOCOL_RE = /^[a-z][a-z\d+.-]*:/i;
+
+function stripInlineMarkdown(value: string): string {
+  return value
+    .replace(/!\[([^\]]*)\]\([^)]+\)/g, "$1")
+    .replace(/\[([^\]]+)\]\([^)]+\)/g, "$1")
+    .replace(/[`*_~]/g, "")
+    .replace(/<[^>]+>/g, "")
+    .trim();
+}
+
+export function markdownSlug(value: string): string {
+  const cleaned = stripInlineMarkdown(value)
+    .normalize("NFKC")
+    .toLowerCase()
+    .replace(/[^\p{L}\p{N}\s._-]+/gu, "")
+    .trim()
+    .replace(/[\s._-]+/g, "-")
+    .replace(/^-+|-+$/g, "");
+  return cleaned || "section";
+}
+
+function decodeLinkPart(value: string): string {
+  try {
+    return decodeURIComponent(value);
+  } catch {
+    return value;
+  }
+}
+
+function normalizeLookupKey(value: string): string {
+  return markdownSlug(decodeLinkPart(value).replace(/^#+/, ""));
+}
+
+function isExternalOrSpecialHref(href: string): boolean {
+  if (href.startsWith("//")) return true;
+  if (PROTOCOL_RE.test(href)) return true;
+  return href.startsWith("/") || href.startsWith("?");
+}
+
+function candidateTextFromHref(href: string): string {
+  const withoutQuery = href.split(/[?#]/)[0] ?? href;
+  const lastSegment = withoutQuery.split("/").filter(Boolean).pop() ?? withoutQuery;
+  return decodeLinkPart(lastSegment).replace(/\.(md|markdown)$/i, "");
+}
+
+export function createMarkdownAnchorResolver(markdown: string): MarkdownAnchorResolver {
+  const headings: MarkdownHeadingAnchor[] = [];
+  const idsByLookup = new Map<string, string>();
+  const seen = new Map<string, number>();
+  let inFence = false;
+
+  for (const rawLine of markdown.split(/\r?\n/)) {
+    const line = rawLine.trim();
+    if (/^(```|~~~)/.test(line)) {
+      inFence = !inFence;
+      continue;
+    }
+    if (inFence) continue;
+
+    const match = HEADING_RE.exec(rawLine);
+    if (!match) continue;
+
+    const level = match[1]!.length;
+    const text = stripInlineMarkdown(match[2]!);
+    const baseId = markdownSlug(text);
+    const count = seen.get(baseId) ?? 0;
+    seen.set(baseId, count + 1);
+    const id = count === 0 ? baseId : `${baseId}-${count}`;
+
+    headings.push({ level, text, id });
+    idsByLookup.set(normalizeLookupKey(text), id);
+    idsByLookup.set(normalizeLookupKey(id), id);
+  }
+
+  return {
+    headings,
+    getHeadingId: (level: number, text: string) => {
+      void level;
+      return idsByLookup.get(normalizeLookupKey(text));
+    },
+    resolveHref: (href: string | undefined, label?: string) => {
+      if (!href) return href;
+      const trimmed = href.trim();
+      if (!trimmed || isExternalOrSpecialHref(trimmed)) return href;
+
+      const hash = trimmed.includes("#") ? trimmed.slice(trimmed.indexOf("#") + 1) : "";
+      const candidates = [
+        hash,
+        trimmed.startsWith("#") ? trimmed.slice(1) : "",
+        candidateTextFromHref(trimmed),
+        label ?? "",
+      ].filter(Boolean);
+
+      for (const candidate of candidates) {
+        const id = idsByLookup.get(normalizeLookupKey(candidate));
+        if (id) return `#${id}`;
+      }
+
+      return trimmed.startsWith("#") ? null : null;
+    },
+  };
+}