export const TRACKING_EVENT_NAME = "developerwebsite_track";
export const LISTENER_QUEUE = "__DX_INSTRUMENTATION_QUEUE__";
export const LISTENER_INDICATOR = "__DX_INSTRUMENTATION_IS_INITIALIZED__";

export function track(
    element: EventTarget,
    event: string,
    payload: Record<string, unknown>
): void {
    const detail = { event, payload };
    // if window.LISTENER_INDICATOR is undefined, `dx-instrumentation` has not
    // been mounted, and the listener hasn't been attached.
    if ((window as any)[LISTENER_INDICATOR] === undefined) {
        (window as any)[LISTENER_QUEUE] = (window as any)[LISTENER_QUEUE] || [];
        (window as any)[LISTENER_QUEUE].push(detail);
    } else {
        const e = new CustomEvent(TRACKING_EVENT_NAME, {
            bubbles: true,
            composed: true,
            detail
        });
        element.dispatchEvent(e);
    }
}

/**
 * Creates a link click handler that tracks analytics and prevents default navigation.
 * Handles links within shadow DOM using composedPath().
 *
 * @param contentCategory - Optional content category for analytics (default: "documentation")
 * @returns Event handler function for link clicks
 */
export function buildDocLinkClickHandler(
    contentCategory: string = "documentation"
): (event: Event) => void {
    return (event: Event): void => {
        // Get the full path including shadow DOM elements
        const path = event.composedPath();

        // Find the first anchor element in the path
        const anchor = path.find((el) => el instanceof HTMLAnchorElement) as
            | HTMLAnchorElement
            | undefined;

        if (anchor && anchor.href && !anchor.href.startsWith("#")) {
            track(anchor, "custEv_linkClick", {
                click_text: anchor.textContent || "",
                click_url: anchor.href,
                element_title: anchor.textContent || "",
                element_type: "link",
                content_category: contentCategory
            });
        }
    };
}