Add typography roles, text primitives, fontkit measurer and layout lint

Txt always sets an absolute line height; RenderTxt never does. Row pins every cell and stacks when the fill column would be too narrow. IdText and FitText shrink then chunk or truncate. The fontkit measurer matches react-pdf text widths exactly. A TypeScript-AST lint test enforces the layout rules (no lineHeight outside Txt, no non-literal fixed/wrap/minPresenceAhead, flexGrow needs flexBasis, no stray absolute positioning).
2026-10-04 04:48:19 +05:30
parent 92ba3d9590
commit 40aa3e05d9
22 changed files with 1375 additions and 34 deletions
@@ -0,0 +1,65 @@
+/**
+ * Typography roles. `leading` is an absolute line height in pt: Txt turns it into `lineHeight: "Npt"`
+ * on the same node as fontSize. Roles used by render-prop text (page numbers) have no leading, because
+ * react-pdf multiplies a render-prop lineHeight again on every relayout.
+ *
+ * These values are the Classic template's; other templates will pass their own token objects.
+ */
+export type FaceKey = "IBM Plex Sans" | "IBM Plex Mono";
+
+export interface TypeToken {
+  face: FaceKey;
+  weight: 300 | 400 | 500 | 600 | 700 | 800;
+  italic?: boolean;
+  size: number;
+  /** pt, absolute. Optional only for tokens used by RenderTxt. */
+  leading?: number;
+  /** em; applied as letterSpacing = tracking * size. */
+  tracking?: number;
+  caps?: boolean;
+  /** Intent only: textkit exposes no OpenType feature switch, so this does not change rendering yet. */
+  tnum?: boolean;
+  /** Smallest size IdText/FitText may shrink to. */
+  minSize?: number;
+}
+
+const SANS: FaceKey = "IBM Plex Sans";
+
+export const TYPE_ROLES = {
+  display: { face: SANS, weight: 600, size: 26, leading: 30 },
+  title: { face: SANS, weight: 600, size: 18, leading: 22, tracking: 1.5 / 18, caps: true },
+  h1: { face: SANS, weight: 600, size: 18, leading: 22 },
+  h2: { face: SANS, weight: 600, size: 13, leading: 17 },
+  body: { face: SANS, weight: 400, size: 9.5, leading: 13.8 },
+  bodyStrong: { face: SANS, weight: 600, size: 9.5, leading: 13.8 },
+  small: { face: SANS, weight: 400, size: 8.5, leading: 12 },
+  fine: { face: SANS, weight: 400, size: 7.5, leading: 10.5 },
+  tableHead: { face: SANS, weight: 400, size: 7.5, leading: 10, tracking: 0.8 / 7.5, caps: true },
+  tableBody: { face: SANS, weight: 400, size: 9.5, leading: 13.8 },
+  money: { face: SANS, weight: 400, size: 9.5, leading: 13.8, tnum: true },
+  moneyStrong: { face: SANS, weight: 600, size: 9.5, leading: 13.8, tnum: true },
+  footer: { face: SANS, weight: 400, size: 7.5 },
+  label: { face: SANS, weight: 400, size: 7.5, leading: 10, tracking: 1 / 7.5, caps: true },
+} as const satisfies Record<string, TypeToken>;
+
+export type RoleName = keyof typeof TYPE_ROLES;
+
+/**
+ * Licensed template faces (Now, Gotham, Open Sauce One, ...) map to the OFL look-alike that is
+ * actually bundled. Empty until those families are registered.
+ */
+export const SUBSTITUTES: Readonly<Record<string, string>> = {};
+
+/** The family name to register/look up for a face: user override first, then substitute, then itself. */
+export function resolveFace(face: string, overrides?: Readonly<Record<string, string>>): string {
+  return overrides?.[face] ?? SUBSTITUTES[face] ?? face;
+}
+
+export function roleToken(role: RoleName | TypeToken): TypeToken {
+  return typeof role === "string" ? TYPE_ROLES[role] : role;
+}
+
+/** Smallest shrink size for a token: its minSize, else 0.9x the size but never below 7 pt (or the size itself). */
+export function minSizeOf(token: TypeToken): number {
+  return token.minSize ?? Math.min(token.size, Math.max(7, token.size * 0.9));
+}