// utils/urlWatcher.ts
// there's a _lot_ of typescript fuckery happening here, because this whole class violates the laws of nature
// please do not be alarmed.
export class UrlWatcher {
    // eslint-disable-next-line no-use-before-define
    private static instance: UrlWatcher;
    private lastUrl: string = window.location.href;

    private constructor() {
        this.patchHistoryMethods();
        this.init();
    }

    static getInstance(): UrlWatcher {
        if (!UrlWatcher.instance) {
            UrlWatcher.instance = new UrlWatcher();
        }
        return UrlWatcher.instance;
    }

    private patchHistoryMethods() {
        const originalPushState = window.history.pushState;
        const originalReplaceState = window.history.replaceState;

        window.history.pushState = function (...args) {
            const result = originalPushState.apply(this, args);
            window.dispatchEvent(new Event("urlchange"));
            return result;
        };

        window.history.replaceState = function (...args) {
            const result = originalReplaceState.apply(this, args);
            window.dispatchEvent(new Event("urlchange"));
            return result;
        };
    }

    private init() {
        // Handle all relevant events
        window.addEventListener("popstate", () => this.checkUrlChange());
        window.addEventListener("urlchange", () => this.checkUrlChange());

        // Fallback for missed changes
        setInterval(() => this.checkUrlChange(), 1000);
    }

    private async checkUrlChange() {
        const currentUrl = window.location.href;
        if (currentUrl !== this.lastUrl) {
            this.lastUrl = currentUrl;
            await this.pingUrl(currentUrl);
        }
    }

    private async pingUrl(url: string) {
        try {
            const response = await fetch(
                url.replace(
                    "localhost:3000",
                    "staging.developer.salesforce.com"
                ),
                {
                    method: "HEAD",
                    redirect: "manual"
                }
            );

            if (
                response.type === "opaqueredirect" ||
                (response.status >= 300 && response.status < 400)
            ) {
                // eslint-disable-next-line no-self-assign
                window.location.href = window.location.href;
            }
        } catch (error) {
            console.error("Error checking URL:", error);
        }
    }
}