export type RouteParams = { [p: string]: string | number } | string[] | string | number;
export type QueryParamsRecord = Record<string, string | number | boolean | null | undefined>;
export type QueryParams = string[][] | QueryParamsRecord | string | URLSearchParams;

export let routes: Record<string, string | undefined> = {};
export function setRoutes(newRoutes: Record<string, string | undefined>): void {
    routes = newRoutes;
}
export function registerRoute(routeName: string, routePath: string): boolean {
    if (!routes[routeName]) {
        routes[routeName] = routePath;
        return true;
    }

    return false;
}

export let publicUrl: string;
export function setPublicUrl(newPublicUrl: string): void {
    publicUrl = newPublicUrl;
}

export function route(
    route: string,
    params: RouteParams = [],
    query: QueryParams = '',
    absolute: boolean = false,
): string {
    let path = routes[route];
    if (path === undefined) throw new Error(`Unknown route for name ${route}.`);

    const regExp = getRouteParamRegExp('[a-zA-Z0-9_-]+', 'g');
    if (typeof params === 'string' || typeof params === 'number') {
        path = path.replace(regExp, '' + params);
    } else if (Array.isArray(params)) {
        let i = 0;
        for (const match of path.matchAll(regExp)) {
            if (match.length > 0) {
                path = path.replace(match[0], typeof params[i] !== 'undefined' ? params[i] : '');
            }
            i++;
        }
        path = path.replace(/\/+/g, '/');
    } else {
        for (const key of Object.keys(params)) {
            path = path.replace(getRouteParamRegExp(key), params[key].toString());
        }
    }

    let filteredQuery: string[][] | Record<string, string> | string | URLSearchParams;
    if (typeof query !== "string" && !(query instanceof URLSearchParams) && !Array.isArray(query)) {
        for (const key of Object.keys(query)) {
            if (query[key] === undefined || query[key] === null) delete query[key];
            else if (typeof query[key] === "number") query[key] = (query[key] as number).toString();
            else if (typeof query[key] === "boolean") query[key] = query[key] ? '1' : '0';
        }
        filteredQuery = query as Record<string, string>;
    } else {
        filteredQuery = query;
    }

    const queryStr = new URLSearchParams(filteredQuery).toString();
    return `${absolute ? publicUrl : ''}${path}` + (queryStr.length > 0 ? '?' + queryStr : '');
}

export function getRouteParamRegExp(key: string, flags?: string): RegExp {
    return new RegExp(`:${key}(\\(.+?\\))?\\??`, flags);
}