/**
 * Loads `aaf_sdk.js` when `window.AmeyoClient` is not already provided by the GWT parent.
 *
 * **Same resolution order as Omni** (`loadOmniSdk.ts`): optional `sdkBaseUrl`, then `origin` query
 * param, then `window.location.origin` — so the script request appears in Network even when the
 * iframe URL has no `origin=` (typical GWT slot: only `instanceId`, etc.).
 *
 * Static path matches **background-app** / ECC war: `/app/build/sdk/1.0.0/aaf_sdk.js`
 *
 * If your ECC mounts the webapp under a path (e.g. `/ameyo40`) and the SDK is not at
 * `{origin}/app/build/...`, pass **`?sdkBaseUrl=https://host:port/ameyo40`** (or `?origin=...`).
 */

function getQueryParam(name: string): string | null {
  const v = new URLSearchParams(window.location.search).get(name);
  return v === null || v.trim() === "" ? null : v.trim();
}

/** Ameyo webapp root used to build the absolute SDK script URL. */
export function getAafSdkBaseUrl(): string {
  const base =
    getQueryParam("sdkBaseUrl") ?? getQueryParam("origin") ?? window.location.origin;
  return String(base).replace(/\/+$/, "");
}

export function getAafSdkScriptUrl(): string {
  return `${getAafSdkBaseUrl()}/app/build/sdk/1.0.0/aaf_sdk.js`;
}

function hasAmeyoClient(): boolean {
  return Boolean(window.AmeyoClient && typeof window.AmeyoClient.init === "function");
}

/**
 * Resolves when `window.AmeyoClient.init` is usable — already present, or after injecting
 * `aaf_sdk.js` from {@link getAafSdkScriptUrl}.
 */
export function ensureAafSdkLoaded(): Promise<void> {
  if (hasAmeyoClient()) {
    return Promise.resolve();
  }

  const src = getAafSdkScriptUrl();

  for (const el of Array.from(document.querySelectorAll("script[src]"))) {
    const sc = el as HTMLScriptElement;
    if (!sc.src.includes("aaf_sdk.js")) continue;
    if (hasAmeyoClient()) return Promise.resolve();
    return new Promise((resolve, reject) => {
      const finish = () => {
        if (hasAmeyoClient()) resolve();
        else reject(new Error("aaf_sdk.js present but window.AmeyoClient.init is still missing"));
      };
      if (sc.readyState === "complete" || sc.readyState === "loaded") {
        finish();
        return;
      }
      sc.addEventListener("load", finish);
      sc.addEventListener("error", () => reject(new Error(`Failed to load ${sc.src || src}`)));
    });
  }

  return new Promise((resolve, reject) => {
    const script = document.createElement("script");
    script.async = true;
    script.src = src;
    script.addEventListener("load", () => {
      if (hasAmeyoClient()) resolve();
      else
        reject(
          new Error(
            `aaf_sdk.js loaded from ${src} but AmeyoClient.init missing — try ?sdkBaseUrl= with your ECC webapp root (e.g. …/ameyo40).`
          )
        );
    });
    script.addEventListener("error", () => {
      reject(
        new Error(
          `Failed to load aaf_sdk.js from ${src}. Set ?sdkBaseUrl= or ?origin= to the Ameyo base URL that serves /app/build/sdk/1.0.0/.`
        )
      );
    });
    document.body.appendChild(script);
  });
}