Export template source from 11bc3ae35b0034c113daca4c35d1b341aa31ef70:examples/local-first/packages/language-reader-runtime

src/variants.ts

@@ -0,0 +1,33 @@
+import { textIndex, processingPolicy } from "./text-processing.js";
+export type VariantSection = { start: number; end: number; text?: string };
+export type TextVariant = {
+  source: string;
+  sourceRevision: string;
+  difficulty: string;
+  sections: VariantSection[];
+};
+/** Canonical ranges never change when an earlier section expands or contracts.
+ * Output offsets are appended in order, so annotations on ready text stay valid. */
+export function createVariant(source: string, sourceRevision: string, difficulty: string): TextVariant {
+  const policy = processingPolicy({ chunkChars: 1400 });
+  return { source, sourceRevision, difficulty, sections: textIndex(source).chunks(policy.chunkChars) };
+}
+export function parseVariant(raw: string): TextVariant | null {
+  const value = JSON.parse(raw);
+  return typeof value.source === "string" && Array.isArray(value.sections) ? value : null;
+}
+export function nextSection(variant: TextVariant) {
+  return variant.sections.find((section) => section.text === undefined);
+}
+export function applySection(variant: TextVariant, start: number, end: number, text: string) {
+  const section = nextSection(variant);
+  if (!section || section.start !== start || section.end !== end) throw Error("Variant section changed");
+  if (!text.trim() || text.length > 12000) throw Error("Invalid variant text");
+  return { ...variant, sections: variant.sections.map((item) => (item === section ? { ...item, text } : item)) };
+}
+export function variantText(variant: TextVariant) {
+  return variant.sections
+    .filter((section) => section.text !== undefined)
+    .map((section) => section.text)
+    .join("\n\n");
+}