Move app to apps/web-react in pnpm workspace layout

apps/web-react/app/utils/compression.ts

@@ -0,0 +1,76 @@
+import { deflateSync, Inflate, strToU8 } from "fflate";
+
+/**
+ * Compresses a string with raw deflate and encodes the result as base64.
+ * With `urlSafe` the output uses the URL-safe base64 alphabet without padding.
+ */
+export function compressToBase64(
+	value: string,
+	options?: { urlSafe?: boolean },
+) {
+	const bytes = deflateSync(strToU8(value), { level: 9 });
+	let binary = "";
+
+	for (const byte of bytes) {
+		binary += String.fromCharCode(byte);
+	}
+
+	const base64 = btoa(binary);
+	if (!options?.urlSafe) return base64;
+
+	return base64.replace(/\+/g, "-").replace(/\//g, "_").replace(/=+$/, "");
+}
+
+/**
+ * Decompresses a base64 encoded (standard or URL-safe alphabet) raw deflate
+ * string. Returns `null` if the input is corrupt or, when
+ * `maxDecompressedBytes` is given, if it inflates past that limit (a
+ * decompression bomb guard for attacker controlled input).
+ */
+export function decompressFromBase64(
+	compressed: string,
+	options?: { maxDecompressedBytes?: number },
+) {
+	const maxDecompressedBytes =
+		options?.maxDecompressedBytes ?? Number.POSITIVE_INFINITY;
+
+	try {
+		const base64 = compressed.replace(/-/g, "+").replace(/_/g, "/");
+
+		const chunks: Array<Uint8Array> = [];
+		let decompressedBytes = 0;
+		const inflator = new Inflate((chunk) => {
+			decompressedBytes += chunk.length;
+			if (decompressedBytes > maxDecompressedBytes) {
+				throw new Error("Decompressed value over the maximum size");
+			}
+			chunks.push(chunk);
+		});
+
+		inflator.push(
+			Uint8Array.from(atob(base64), (c) => c.charCodeAt(0)),
+			true,
+		);
+
+		const value = new TextDecoder().decode(concatChunks(chunks));
+
+		if (!value) return null;
+
+		return value;
+	} catch {
+		return null;
+	}
+}
+
+function concatChunks(chunks: Array<Uint8Array>) {
+	const totalBytes = chunks.reduce((total, chunk) => total + chunk.length, 0);
+	const result = new Uint8Array(totalBytes);
+
+	let offset = 0;
+	for (const chunk of chunks) {
+		result.set(chunk, offset);
+		offset += chunk.length;
+	}
+
+	return result;
+}