initial 2

apps/web/src/lib/ai/prompts/render.ts

@@ -0,0 +1,41 @@
+const PLACEHOLDER_RE = /\{\{(\w+)\}\}/g;
+
+export function renderTemplate(
+  body: string,
+  data: Record<string, string | number | unknown>
+): string {
+  return body.replace(PLACEHOLDER_RE, (_, key: string) => {
+    const val = data[key];
+    if (val === undefined || val === null) return `{{${key}}}`;
+    if (typeof val === "object") return JSON.stringify(val);
+    return String(val);
+  });
+}
+
+export function findMissingPlaceholders(
+  body: string,
+  data: Record<string, unknown>
+): string[] {
+  const missing: string[] = [];
+  let match;
+  const re = /\{\{(\w+)\}\}/g;
+  while ((match = re.exec(body)) !== null) {
+    const key = match[1];
+    if (data[key] === undefined && !missing.includes(key)) {
+      missing.push(key);
+    }
+  }
+  return missing;
+}
+
+export const SAMPLE_PREVIEW_DATA: Record<string, unknown> = {
+  user_name: "Traveler",
+  context: { level: 5, recentReading: 42, exerciseDays: 3 },
+  topic: "Stoic philosophy",
+  week_summary: "You read 35 pages, prayed 4 days, and exercised twice.",
+  reading_progress: "Currently reading page 120 of 300",
+  exercise_summary: "2 exercise sessions this week",
+  prayer_summary: "4 of 5 morning prayers completed",
+  learning_topics: "Roman history, Latin roots",
+  chronicle_context: "Chapter 3: The Long Road — 45 days on the journey",
+};