import { appGlobals } from './globals.js'

export async function loadWasmModule(filePath, environment)
{
	let result = null;
	try
	{
		const fetchPromise = fetch(filePath);
		const wasmModule = await WebAssembly.instantiateStreaming(
			fetchPromise,
			{ env: environment }
		);
		result = wasmModule.instance;
	}
	catch (exception)
	{
		console.error("Failed to load WASM module from \"" + filePath + "\":", exception);
	}
	return result;
}

//TODO: We should do some performance measurements of wasmPntrToJsString vs wasmPntrAndLengthToJsString!
export function wasmPntrToJsString(ptr)
{
	let cIndex = ptr;
	while (cIndex < appGlobals.memDataView.byteLength)
	{
		let byteValue = appGlobals.memDataView.getUint8(cIndex, true);
		if (byteValue == 0) { break; }
		cIndex++;
	}
	return appGlobals.textDecoder.decode(
		appGlobals.memDataView.buffer.slice(ptr, cIndex)
	);
}
export function wasmPntrAndLengthToJsString(ptr, length)
{
	return appGlobals.textDecoder.decode(
		appGlobals.memDataView.buffer.slice(ptr, ptr + length)
	);
}