import { DeviceUtilities } from "./engine_utils.js";

/**
 * Arguments for the native screenshot bridge exposed by the Needle Go App Clip (injected as `window.NeedleGoNativeScreenshot`).
 */
declare type NeedleGoNativeScreenshotArgs = {
    /** Data URL (PNG) of the rendered 3D layer with a transparent background. Native code composites the live camera frame behind it. */
    image: string;
    /** "share" presents the native share sheet, "return" sends the composited image back. @default "share" */
    action?: "share" | "return";
    /** Share sheet title (action "share") */
    title?: string;
    /** Share sheet text (action "share") */
    text?: string;
    /** Share sheet url (action "share") */
    url?: string;
    /** Mime type for the returned image (action "return"): "image/png" or "image/jpeg" (default jpeg, the composite is opaque) */
    mimeType?: string;
    /** JPEG quality 0..1 for action "return" (default 0.9) */
    quality?: number;
}

declare type NeedleGoNativeScreenshotResult = {
    /** action "share": whether the user completed the share */
    shared?: boolean;
    /** action "share": the activity the user chose, if any */
    activity?: string;
    /** action "return": data URL of the composited image */
    image?: string;
    /** action "return": mime type of the returned image */
    mimeType?: string;
}

declare type NeedleGoNativeScreenshotFunction = (args: NeedleGoNativeScreenshotArgs) => Promise<NeedleGoNativeScreenshotResult>;

/**
 * Returns the native screenshot bridge when running inside the Needle Go App Clip.
 *
 * In the App Clip the camera feed is rendered natively *behind* the transparent webview,
 * so the page can never capture it (there is no `camera-access` WebXR feature). The bridge
 * lets us send the rendered 3D layer to the native app, which composites the current camera
 * frame behind it and can present the native share sheet — which, unlike `navigator.share`,
 * does not require (transient) user activation, so a single tap is enough even though the
 * screenshot pipeline is asynchronous.
 *
 * Returns null when not in the App Clip or when the App Clip version doesn't support it yet.
 */
export function getNativeScreenshotBridge(): NeedleGoNativeScreenshotFunction | null {
    if (typeof window === "undefined") return null;
    if (!DeviceUtilities.isNeedleAppClip()) return null;
    const fn = (window as any).NeedleGoNativeScreenshot;
    return typeof fn === "function" ? fn as NeedleGoNativeScreenshotFunction : null;
}