feat: frontend support.

js/src/wasm-loader.ts

@@ -1,7 +1,94 @@
-// @ts-expect-error — glue file is generated, no types available
-import ModuleFactory from "../../dist/anisette_rs.node.js";
+// Unified WASM loader with automatic environment detection
+// Uses import.meta.url + protocol detection to support both Node.js and Browser
+//
+// Browser (Vite/Webpack/etc):  https://... or http://... -> anisette_rs.js + .wasm
+// Node.js:                     file://...                 -> anisette_rs.node.js + .wasm
 
+// Get the base URL from import.meta.url
+const MODULE_URL = new URL(import.meta.url);
+const IS_NODE = MODULE_URL.protocol === "file:";
+
+// Determine which WASM build to use based on environment
+const WASM_JS_PATH = IS_NODE
+  ? new URL("../dist/anisette_rs.node.js", MODULE_URL)
+  : new URL("../dist/anisette_rs.js", MODULE_URL);
+
+const WASM_BINARY_PATH = IS_NODE
+  ? new URL("../dist/anisette_rs.node.wasm", MODULE_URL)
+  : new URL("../dist/anisette_rs.wasm", MODULE_URL);
+
+// Module overrides type (Emscripten module configuration)
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
-export async function loadWasm(moduleOverrides?: Record<string, any>): Promise<any> {
-  return ModuleFactory({ ...moduleOverrides });
+export type EmscriptenModule = any;
+
+export interface ModuleOverrides {
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  [key: string]: any;
 }
+
+/**
+ * Load the Emscripten WASM module with automatic environment detection.
+ *
+ * This function automatically:
+ * - Detects Node.js vs Browser environment via import.meta.url protocol
+ * - Loads the appropriate WASM build (node or web)
+ * - Configures locateFile to find the .wasm binary
+ * - Initializes the module with optional overrides
+ *
+ * @param moduleOverrides - Optional Emscripten module configuration overrides
+ * @returns Initialized Emscripten module with all exports (_malloc, _free, _anisette_* etc.)
+ *
+ * @example
+ * ```ts
+ * // Browser (Vue/React/Next.js) and Node.js - same code!
+ * const module = await loadWasmModule();
+ *
+ * // With custom overrides
+ * const module = await loadWasmModule({
+ *   print: (text: string) => console.log("WASM:", text),
+ *   printErr: (text: string) => console.error("WASM Error:", text),
+ * });
+ * ```
+ */
+export async function loadWasmModule(
+  moduleOverrides: ModuleOverrides = {}
+): Promise<EmscriptenModule> {
+  // Dynamic import of the appropriate Emscripten glue file
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  const { default: ModuleFactory } = await import(/* @vite-ignore */ WASM_JS_PATH.href) as { default: (config: ModuleOverrides) => Promise<EmscriptenModule> };
+
+  // In browser: let Emscripten use default fetch behavior
+  // In Node.js: provide locateFile to resolve the .wasm path
+  const config: ModuleOverrides = IS_NODE
+    ? {
+        ...moduleOverrides,
+        locateFile: (filename: string) => {
+          if (filename.endsWith(".wasm")) {
+            // In Node.js, return the absolute file path
+            return WASM_BINARY_PATH.pathname;
+          }
+          return filename;
+        },
+      }
+    : moduleOverrides;
+
+  return ModuleFactory(config);
+}
+
+/**
+ * Convenience function to check if running in Node.js environment.
+ * Uses the same protocol detection as the loader.
+ */
+export function isNodeEnvironment(): boolean {
+  return IS_NODE;
+}
+
+/**
+ * Get the resolved WASM binary path (useful for debugging).
+ */
+export function getWasmBinaryPath(): string {
+  return IS_NODE ? WASM_BINARY_PATH.pathname : WASM_BINARY_PATH.href;
+}
+
+// Re-export for backward compatibility
+export { loadWasmModule as loadWasm };