Initial work of ESM transformation

utility/make-webfont-css.mjs

@@ -0,0 +1,49 @@
+import fs from "fs";
+
+const WebfontFormatMap = new Map([
+	["woff2", "woff2"],
+	["ttf", "truetype"]
+]);
+export default (function (output, family, hs, formats, unhinted) {
+	if (!formats) {
+		fs.writeFileSync(output, "");
+		return;
+	}
+	let ans = ``;
+	for (const ext of formats) {
+		if (!WebfontFormatMap.get(ext)) throw new TypeError("Invalid webfont file format " + ext);
+	}
+	for (const term of hs) {
+		const dirSuffix = unhinted ? "-unhinted" : "";
+		const src = formats
+			.map(
+				ext =>
+					`url('${ext}${dirSuffix}/${term.name}.${ext}') ` +
+					`format('${WebfontFormatMap.get(ext)}')`
+			)
+			.join(", ");
+		ans += `
+@font-face {
+	font-family: '${family + " Web"}';
+	font-display: swap;
+	font-weight: ${term.css.weight};
+	font-stretch: ${term.css.stretch};
+	font-style: ${term.css.style};
+	src: ${src};
+}
+`;
+		if (term.css.style === "oblique") {
+			// CHROME hates a family with both Italic and Oblique
+			ans += `
+@font-face {
+	font-family: '${family + " Web Oblique"}';
+	font-display: swap;
+	font-weight: ${term.css.weight};
+	font-stretch: ${term.css.stretch};
+	src: ${src};
+}
+`;
+		}
+	}
+	fs.writeFileSync(output, ans);
+});