/**
 * Route Detection Utilities
 * Shared logic for detecting route changes across different AI chat platforms
 */

import { UI_CONFIG } from "./constants";

export interface RouteDetectionConfig {
	platform: string;
	selectors: string[];
	reinitCallback: () => void;
	checkInterval?: number;
	observerThrottleDelay?: number;
}

export interface RouteDetectionCleanup {
	observer: MutationObserver | null;
	urlCheckInterval: NodeJS.Timeout | null;
	observerThrottle: NodeJS.Timeout | null;
}

export function createRouteDetection(
	config: RouteDetectionConfig,
	cleanup: RouteDetectionCleanup,
): void {
	if (cleanup.observer) {
		cleanup.observer.disconnect();
	}
	if (cleanup.urlCheckInterval) {
		clearInterval(cleanup.urlCheckInterval);
	}
	if (cleanup.observerThrottle) {
		clearTimeout(cleanup.observerThrottle);
		cleanup.observerThrottle = null;
	}

	let currentUrl = window.location.href;

	const checkForRouteChange = () => {
		if (window.location.href !== currentUrl) {
			currentUrl = window.location.href;
			console.log(`${config.platform} route changed, re-initializing`);
			setTimeout(config.reinitCallback, 1000);
		}
	};

	cleanup.urlCheckInterval = setInterval(
		checkForRouteChange,
		config.checkInterval || UI_CONFIG.ROUTE_CHECK_INTERVAL,
	);

	cleanup.observer = new MutationObserver((mutations) => {
		if (cleanup.observerThrottle) {
			return;
		}

		let shouldRecheck = false;
		mutations.forEach((mutation) => {
			if (mutation.type === "childList" && mutation.addedNodes.length > 0) {
				mutation.addedNodes.forEach((node) => {
					if (node.nodeType === Node.ELEMENT_NODE) {
						const element = node as Element;

						for (const selector of config.selectors) {
							if (
								element.querySelector?.(selector) ||
								element.matches?.(selector)
							) {
								shouldRecheck = true;
								break;
							}
						}
					}
				});
			}
		});

		if (shouldRecheck) {
			cleanup.observerThrottle = setTimeout(() => {
				try {
					cleanup.observerThrottle = null;
					config.reinitCallback();
				} catch (error) {
					console.error(
						`Error in ${config.platform} observer callback:`,
						error,
					);
				}
			}, config.observerThrottleDelay || UI_CONFIG.OBSERVER_THROTTLE_DELAY);
		}
	});

	try {
		cleanup.observer.observe(document.body, {
			childList: true,
			subtree: true,
		});
	} catch (error) {
		console.error(`Failed to set up ${config.platform} route observer:`, error);
		if (cleanup.urlCheckInterval) {
			clearInterval(cleanup.urlCheckInterval);
		}
		cleanup.urlCheckInterval = setInterval(checkForRouteChange, 1000);
	}
}

export function cleanupRouteDetection(cleanup: RouteDetectionCleanup): void {
	if (cleanup.observer) {
		cleanup.observer.disconnect();
		cleanup.observer = null;
	}
	if (cleanup.urlCheckInterval) {
		clearInterval(cleanup.urlCheckInterval);
		cleanup.urlCheckInterval = null;
	}
	if (cleanup.observerThrottle) {
		clearTimeout(cleanup.observerThrottle);
		cleanup.observerThrottle = null;
	}
}