1 files changed, 409 insertions, 0 deletions
diff --git a/src/utils/steamLaunchOptions.ts b/src/utils/steamLaunchOptions.ts
new file mode 100644
index 0000000..83c46f2
--- /dev/null
+++ b/src/utils/steamLaunchOptions.ts
@@ -0,0 +1,409 @@
+const DEFAULT_WRAPPER_PATH = "~/.lsfg";
+const COMMAND_TOKEN = "%command%";
+
+export const LEGACY_WRAPPER_TOKENS = new Set([
+  "~/lsfg",
+  "~/.local/bin/lsfg",
+  "~/.local/bin/lsfg-vk-experimental",
+  "~/.local/bin/mako-run",
+  "mako-run",
+  "~/.local/bin/mako-launch",
+  "mako-launch",
+]);
+
+const LEGACY_ABSOLUTE_WRAPPER = /^\/(?:home|Users)\/[^/]+\/(?:lsfg|\.local\/bin\/(?:lsfg|lsfg-vk-experimental|mako-run|mako-launch))$/;
+const MANAGED_ENV_KEYS = new Set([
+  "ENABLE_GAMESCOPE_WSI", "DISABLE_GAMESCOPE_WSI", "DXVK_HDR", "SteamDeck",
+  "DISABLE_VKBASALT", "ENABLE_VKBASALT", "MESA_LOADER_DRIVER_OVERRIDE",
+  "__GLX_VENDOR_LIBRARY_NAME", "GALLIUM_DRIVER", "DXVK_FRAME_RATE",
+]);
+const DXVK_FRAME_RATE_SEGMENT = /^(?:dxvk\.maxFrameRate|dxgi\.maxFrameRate|d3d9\.maxFrameRate)\s*=/i;
+
+interface LaunchToken { raw: string; value: string; }
+export interface SteamLaunchOptionsSnapshot {
+  appId: number;
+  nonSteam: boolean;
+  options: string;
+  details: SteamAppDetails;
+}
+export interface WrapperIntegrationResult {
+  snapshot: SteamLaunchOptionsSnapshot;
+  commandTokenAdded: boolean;
+  changed: boolean;
+}
+
+function asError(error: unknown): Error {
+  return error instanceof Error ? error : new Error(String(error));
+}
+
+function apps(): Partial<SteamApps> | undefined {
+  return (globalThis as typeof globalThis & { SteamClient?: { Apps?: Partial<SteamApps> } }).SteamClient?.Apps;
+}
+
+function validateAppId(appId: number): void {
+  if (!Number.isSafeInteger(appId) || appId <= 0) throw new Error("Invalid Steam App ID");
+}
+
+function timer() {
+  const host = typeof window !== "undefined" ? window : globalThis;
+  return {
+    set: (handler: () => void, ms: number) => host.setTimeout(handler, ms) as unknown as number,
+    clear: (id: number) => host.clearTimeout(id),
+  };
+}
+
+function snapshot(appId: number, nonSteam: boolean, details: SteamAppDetails): SteamLaunchOptionsSnapshot {
+  return {
+    appId,
+    nonSteam,
+    options: nonSteam ? details.strShortcutLaunchOptions || "" : details.strLaunchOptions || "",
+    details,
+  };
+}
+
+function registerDetails(appId: number, onDetails: (details: SteamAppDetails) => boolean | void): () => void {
+  validateAppId(appId);
+  const register = apps()?.RegisterForAppDetails;
+  if (!register) throw new Error("Steam app-details API is unavailable");
+  let active = true;
+  let registration: SteamAppDetailsRegistration | undefined;
+  const unsubscribe = () => {
+    active = false;
+    try { registration?.unregister(); } catch {}
+  };
+  registration = register.call(apps(), appId, (details) => {
+    if (active && onDetails(details || {}) === false) unsubscribe();
+  });
+  if (!active) unsubscribe();
+  return unsubscribe;
+}
+
+export async function readSteamLaunchOptions(appId: number, nonSteam: boolean): Promise<SteamLaunchOptionsSnapshot> {
+  return new Promise((resolve, reject) => {
+    let done = false;
+    let unsubscribe = () => {};
+    const clock = timer();
+    const timeout = clock.set(() => finish(new Error("Timed out reading Steam app details")), 5000);
+    const finish = (error?: unknown, details?: SteamAppDetails) => {
+      if (done) return;
+      done = true;
+      clock.clear(timeout);
+      unsubscribe();
+      if (error) reject(asError(error));
+      else resolve(snapshot(appId, nonSteam, details || {}));
+    };
+    try {
+      unsubscribe = registerDetails(appId, (details) => {
+        finish(undefined, details);
+        return false;
+      });
+    } catch (error) {
+      finish(error);
+    }
+  });
+}
+
+export function subscribeSteamLaunchOptions(
+  appId: number,
+  nonSteam: boolean,
+  onSnapshot: (value: SteamLaunchOptionsSnapshot) => void,
+  onError: (error: Error) => void,
+): () => void {
+  return registerDetails(appId, (details) => {
+    try { onSnapshot(snapshot(appId, nonSteam, details)); }
+    catch (error) { onError(asError(error)); }
+  });
+}
+
+function decodeToken(raw: string): string {
+  let value = "";
+  let quote: "'" | '"' | null = null;
+  for (let i = 0; i < raw.length; i++) {
+    const c = raw[i];
+    if (c === "\\" && quote !== "'" && i + 1 < raw.length) value += raw[++i];
+    else if (quote) { if (c === quote) quote = null; else value += c; }
+    else if (c === "'" || c === '"') quote = c;
+    else value += c;
+  }
+  return value;
+}
+
+function tokenize(options: string): LaunchToken[] {
+  const tokens: LaunchToken[] = [];
+  let start = -1;
+  let quote: "'" | '"' | null = null;
+  let escaped = false;
+  const push = (end: number) => {
+    if (start < 0) return;
+    const raw = options.slice(start, end);
+    tokens.push({ raw, value: decodeToken(raw) });
+    start = -1;
+  };
+  for (let i = 0; i < options.length; i++) {
+    const c = options[i];
+    if (start < 0) { if (/\s/.test(c)) continue; start = i; }
+    if (escaped) escaped = false;
+    else if (c === "\\" && quote !== "'") escaped = true;
+    else if (quote) { if (c === quote) quote = null; }
+    else if (c === "'" || c === '"') quote = c;
+    else if (/\s/.test(c)) push(i);
+  }
+  push(options.length);
+  return tokens;
+}
+
+const serialize = (tokens: readonly LaunchToken[]) => tokens.map(({ raw }) => raw).join(" ");
+function isCommandToken(token: LaunchToken): boolean {
+  return token.value.toLowerCase() === COMMAND_TOKEN;
+}
+
+function isMalformedCommandToken(token: LaunchToken): boolean {
+  const value = token.value.toLowerCase();
+  return value === "%command" || value === "command%";
+}
+
+function normalizeCommandTokens(tokens: LaunchToken[]): void {
+  for (const token of tokens) {
+    if (isCommandToken(token) || isMalformedCommandToken(token)) {
+      token.raw = COMMAND_TOKEN;
+      token.value = COMMAND_TOKEN;
+    }
+  }
+}
+
+const commandIndex = (tokens: readonly LaunchToken[]) => tokens.findIndex(isCommandToken);
+const isAssignment = (token: LaunchToken) => /^[A-Za-z_][A-Za-z0-9_]*=/.test(token.value);
+const isLegacyToken = (value: string) => LEGACY_WRAPPER_TOKENS.has(value) || LEGACY_ABSOLUTE_WRAPPER.test(value);
+const isWrapperToken = (value: string, wrapperPath: string) => decodeToken(value) === wrapperPath || isLegacyWrapperToken(value);
+
+export const normalizeLaunchOptions = (options: string) => serialize(tokenize(options));
+export const isLegacyWrapperToken = (value: string) => isLegacyToken(decodeToken(value));
+
+function removeMatchingWrappers(tokens: LaunchToken[], predicate: (value: string) => boolean): boolean {
+  const command = commandIndex(tokens);
+  const prefixEnd = command >= 0 ? command : tokens.length;
+  const kept = tokens.filter((token, i) => i >= prefixEnd || !predicate(token.value));
+  if (kept.length === tokens.length) return false;
+  tokens.splice(0, tokens.length, ...kept);
+  return true;
+}
+
+function installLaunchOption(
+  options: string,
+  wrapperPath = DEFAULT_WRAPPER_PATH,
+) {
+  const tokens = tokenize(options);
+  normalizeCommandTokens(tokens);
+  removeMatchingWrappers(tokens, isLegacyToken);
+  let command = commandIndex(tokens);
+  if (command >= 0) {
+    if (tokens[command - 1]?.value === wrapperPath) return { options: serialize(tokens), commandTokenAdded: false };
+    removeMatchingWrappers(tokens, (value) => decodeToken(value) === wrapperPath);
+    command = commandIndex(tokens);
+    tokens.splice(command, 0, { raw: wrapperPath, value: wrapperPath });
+    return { options: serialize(tokens), commandTokenAdded: false };
+  }
+
+  const existingWrapper = tokens.findIndex((token) => decodeToken(token.value) === wrapperPath);
+  if (existingWrapper >= 0) {
+    tokens.splice(existingWrapper + 1, 0, { raw: COMMAND_TOKEN, value: COMMAND_TOKEN });
+    return { options: serialize(tokens), commandTokenAdded: true };
+  }
+
+  let insertion = 0;
+  while (insertion < tokens.length && isAssignment(tokens[insertion])) insertion++;
+  tokens.splice(insertion, 0,
+    { raw: wrapperPath, value: wrapperPath },
+    { raw: COMMAND_TOKEN, value: COMMAND_TOKEN },
+  );
+  return { options: serialize(tokens), commandTokenAdded: true };
+}
+
+export function installWrapperLaunchOption(options: string, wrapperPath = DEFAULT_WRAPPER_PATH) {
+  return installLaunchOption(options, wrapperPath);
+}
+
+export function removeWrapperLaunchOption(
+  options: string,
+  wrapperPath = DEFAULT_WRAPPER_PATH,
+  commandTokenAdded = false,
+): string {
+  const tokens = tokenize(options);
+  normalizeCommandTokens(tokens);
+  if (removeMatchingWrappers(tokens, (value) => isWrapperToken(value, wrapperPath)) && commandTokenAdded) {
+    const command = commandIndex(tokens);
+    if (command >= 0) tokens.splice(command, 1);
+  }
+  return serialize(tokens);
+}
+
+function encodeAssignmentValue(value: string): string {
+  return /^[A-Za-z0-9_./:+,%=-]+$/.test(value)
+    ? value
+    : `"${value.replace(/\\/g, "\\\\").replace(/"/g, '\\"')}"`;
+}
+
+export function cleanupPluginAssignments(options: string): string {
+  const tokens = tokenize(options);
+  const command = commandIndex(tokens);
+  const prefixEnd = command >= 0 ? command : tokens.length;
+  return serialize(tokens.flatMap((token, i) => {
+    if (i >= prefixEnd || !isAssignment(token)) return [token];
+    const split = token.value.indexOf("=");
+    const key = token.value.slice(0, split);
+    if (key === "DXVK_CONFIG") {
+      const value = token.value.slice(split + 1).split(";").map((part) => part.trim())
+        .filter((part) => part && !DXVK_FRAME_RATE_SEGMENT.test(part)).join("; ");
+      return value ? [{ raw: `DXVK_CONFIG=${encodeAssignmentValue(value)}`, value: `DXVK_CONFIG=${value}` }] : [];
+    }
+    return MANAGED_ENV_KEYS.has(key) ? [] : [token];
+  }));
+}
+
+export function cleanupLegacyLaunchOptions(options: string): string {
+  const tokens = tokenize(options);
+  removeMatchingWrappers(tokens, isLegacyToken);
+  return serialize(tokens);
+}
+export const cleanupPluginLaunchOptions = (options: string, wrapperPath = DEFAULT_WRAPPER_PATH) =>
+  cleanupPluginAssignments(removeWrapperLaunchOption(options, wrapperPath));
+export const cleanupLegacyWrapper = cleanupPluginLaunchOptions;
+export function hasWrapperLaunchIntegration(options: string, wrapperPath = DEFAULT_WRAPPER_PATH): boolean {
+  const tokens = tokenize(options);
+  const command = commandIndex(tokens);
+  return command > 0 && tokens[command - 1].value === wrapperPath;
+}
+
+export function isWrapperIntegrationInstalled(
+  steam: SteamLaunchOptionsSnapshot,
+  _nonSteam: boolean,
+  wrapperPath = DEFAULT_WRAPPER_PATH,
+): boolean {
+  return hasWrapperLaunchIntegration(steam.options, wrapperPath);
+}
+
+const queues = new Map<string, Promise<unknown>>();
+function queued<T>(appId: number, nonSteam: boolean, operation: () => Promise<T>): Promise<T> {
+  const key = `${nonSteam ? "shortcut" : "app"}:${appId}`;
+  const previous = queues.get(key) || Promise.resolve();
+  const current = previous.catch(() => undefined).then(operation);
+  const cleanup = current.then(
+    () => { if (queues.get(key) === cleanup) queues.delete(key); },
+    () => { if (queues.get(key) === cleanup) queues.delete(key); },
+  );
+  queues.set(key, cleanup);
+  return current;
+}
+
+async function waitFor(
+  appId: number,
+  nonSteam: boolean,
+  matches: (value: SteamLaunchOptionsSnapshot) => boolean,
+  message: string,
+): Promise<SteamLaunchOptionsSnapshot> {
+  const deadline = Date.now() + 5000;
+  let lastError: Error | null = null;
+  while (Date.now() <= deadline) {
+    try {
+      const value = await readSteamLaunchOptions(appId, nonSteam);
+      if (matches(value)) return value;
+    } catch (error) { lastError = asError(error); }
+    if (Date.now() < deadline) await new Promise((resolve) => timer().set(resolve as () => void, 100));
+  }
+  throw lastError ? new Error(`${message}: ${lastError.message}`) : new Error(`${message} before the readback timeout`);
+}
+
+async function writeVerified(
+  appId: number,
+  nonSteam: boolean,
+  previous: string,
+  next: string,
+  write: (value: string) => Promise<void>,
+  message: string,
+): Promise<SteamLaunchOptionsSnapshot> {
+  try {
+    await write(next);
+    return await waitFor(appId, nonSteam, (value) => normalizeLaunchOptions(value.options) === normalizeLaunchOptions(next), message);
+  } catch (error) {
+    const failure = asError(error);
+    try {
+      await write(previous);
+      await waitFor(appId, nonSteam, (value) => normalizeLaunchOptions(value.options) === normalizeLaunchOptions(previous), "Steam did not restore the previous launch options");
+    } catch (rollback) {
+      throw new Error(`${failure.message}; rollback also failed: ${asError(rollback).message}`);
+    }
+    throw failure;
+  }
+}
+
+function writeOptions(appId: number, nonSteam: boolean, value: string): Promise<void> {
+  const setter = nonSteam ? apps()?.SetShortcutLaunchOptions : apps()?.SetAppLaunchOptions;
+  if (!setter) return Promise.reject(new Error(`Steam ${nonSteam ? "shortcut " : ""}launch options API is unavailable`));
+  return Promise.resolve(setter.call(apps(), appId, value));
+}
+
+export function updateSteamLaunchOptions(
+  appId: number,
+  nonSteam: boolean,
+  transform: (options: string) => string,
+): Promise<SteamLaunchOptionsSnapshot> {
+  return queued(appId, nonSteam, async () => {
+    const current = await readSteamLaunchOptions(appId, nonSteam);
+    const next = transform(current.options);
+    return next === current.options ? current : writeVerified(
+      appId, nonSteam, current.options, next,
+      (value) => writeOptions(appId, nonSteam, value),
+      "Steam did not accept the launch options",
+    );
+  });
+}
+
+export function installWrapperIntegration(
+  appId: number,
+  nonSteam: boolean,
+  wrapperPath: string,
+  commandTokenAdded = false,
+): Promise<WrapperIntegrationResult> {
+  return queued(appId, nonSteam, async () => {
+    const current = await readSteamLaunchOptions(appId, nonSteam);
+    const cleaned = cleanupPluginAssignments(cleanupLegacyLaunchOptions(current.options));
+    const alreadyInstalled = hasWrapperLaunchIntegration(current.options, wrapperPath);
+    const rewrite = installLaunchOption(cleaned, wrapperPath);
+    if (rewrite.options === current.options) return { snapshot: current, commandTokenAdded, changed: false };
+    const value = await writeVerified(
+      appId, nonSteam, current.options, rewrite.options,
+      (options) => writeOptions(appId, nonSteam, options),
+      "Steam did not accept the launch options",
+    );
+    return {
+      snapshot: value,
+      commandTokenAdded: alreadyInstalled ? commandTokenAdded : commandTokenAdded || rewrite.commandTokenAdded,
+      changed: true,
+    };
+  });
+}
+
+export function removeWrapperIntegration(
+  appId: number,
+  nonSteam: boolean,
+  wrapperPath: string,
+  commandTokenAdded = false,
+): Promise<SteamLaunchOptionsSnapshot> {
+  return queued(appId, nonSteam, async () => {
+    const current = await readSteamLaunchOptions(appId, nonSteam);
+    const next = cleanupPluginAssignments(removeWrapperLaunchOption(current.options, wrapperPath, commandTokenAdded));
+    return next === current.options ? current : writeVerified(
+      appId, nonSteam, current.options, next,
+      (options) => writeOptions(appId, nonSteam, options),
+      "Steam did not clean the launch options",
+    );
+  });
+}
+
+export const cleanupLegacySteamLaunchOptions = (
+  appId: number,
+  nonSteam: boolean,
+  wrapperPath = DEFAULT_WRAPPER_PATH,
+) => updateSteamLaunchOptions(appId, nonSteam, (options) => cleanupPluginLaunchOptions(options, wrapperPath));
+
+export const getDefaultWrapperPath = () => DEFAULT_WRAPPER_PATH;