Files
Voiced/scripts/fonts/lib.mjs
T
xavierk 92ba3d9590 Add bundled TTF fonts, page geometry, column allocator and render model
Static TTF fonts (IBM Plex Sans/Mono, Noto Devanagari/Kannada) with a
fontkit-generated manifest, a verifier and OFL licences. Every family
registers a normal and italic source so fallback stacks cannot throw.
Adds A4/Letter geometry with margin presets, an exact column allocator,
deterministic Indian-grouping money and date formatting, text sanitising
and a pure buildRenderModel.
2026-10-04 04:38:03 +05:30

80 lines
3.0 KiB
JavaScript

// Shared helpers for the font manifest builder and verifier (Node only).
import { createHash } from "node:crypto";
import { readdirSync, readFileSync, statSync } from "node:fs";
import path from "node:path";
import { fileURLToPath } from "node:url";
import * as fontkit from "fontkit";
export const ROOT = path.resolve(path.dirname(fileURLToPath(import.meta.url)), "../..");
export const FONTS_DIR = path.join(ROOT, "public/fonts");
export const MANIFEST_PATH = path.join(FONTS_DIR, "manifest.json");
export const sha256 = (bytes) => createHash("sha256").update(bytes).digest("hex");
/** Folders under public/fonts that hold bundled families (everything that is a directory). */
export function familyFolders() {
return readdirSync(FONTS_DIR)
.filter((name) => statSync(path.join(FONTS_DIR, name)).isDirectory())
.sort();
}
export function ttfFiles(folder) {
return readdirSync(path.join(FONTS_DIR, folder))
.filter((name) => /\.ttf$/i.test(name))
.sort();
}
/** First four bytes as a tag: "\0\1\0\0" is reported as "0x00010000". */
export function sfntTag(bytes) {
const b = bytes.subarray(0, 4);
if (b[0] === 0 && b[1] === 1 && b[2] === 0 && b[3] === 0) return "0x00010000";
return String.fromCharCode(...b);
}
/** Raw OS/2 fsType (fontkit only exposes decoded flags). */
function rawFsType(bytes) {
const dv = new DataView(bytes.buffer, bytes.byteOffset, bytes.byteLength);
const numTables = dv.getUint16(4);
for (let i = 0; i < numTables; i++) {
const rec = 12 + i * 16;
const tag = String.fromCharCode(bytes[rec], bytes[rec + 1], bytes[rec + 2], bytes[rec + 3]);
if (tag === "OS/2") return dv.getUint16(dv.getUint32(rec + 8) + 8);
}
return null;
}
/** Reads a TTF with fontkit and returns the facts the manifest records. */
export function inspectFont(folder, file) {
const bytes = new Uint8Array(readFileSync(path.join(FONTS_DIR, folder, file)));
const font = fontkit.create(Buffer.from(bytes));
if (font.fonts) throw new Error(`${folder}/${file}: font collections are not supported`);
const os2 = font["OS/2"];
return {
bytes,
tag: sfntTag(bytes),
variable: Boolean(font.directory?.tables?.fvar),
// Name ID 16 (typographic family) groups SemiBold etc. under the base family.
familyName: font.name?.records?.preferredFamily?.en ?? font.familyName,
info: {
file,
weight: os2.usWeightClass,
style: os2.fsSelection.italic || os2.fsSelection.oblique ? "italic" : "normal",
sha256: sha256(bytes),
fsType: rawFsType(bytes),
upm: font.unitsPerEm,
ascent: font.ascent,
descent: font.descent,
lineGap: font.lineGap,
capHeight: font.capHeight,
xHeight: font.xHeight,
hasRupee: font.hasGlyphForCodePoint(0x20b9),
hasTabularNums: font.availableFeatures.includes("tnum"),
},
};
}
export const WEIGHT_WORDS = {
Thin: 100, ExtraLight: 200, Light: 300, Regular: 400, Italic: 400, Text: 450,
Medium: 500, SemiBold: 600, Bold: 700, ExtraBold: 800, Black: 900,
};