const levels = ['province_id', 'district_id', 'admin_post_id', 'locality_id'];
const searchRoutes = ['/carteira', '/oportunidades', '/zonas', '/educacao'];

/** Keep search geography explicit; a documentary origin is never an invented offer. */
export function portfolioPreparationHref(id: string, pageUrl: string): string {
    const source = new URL(pageUrl, 'https://portal.invalid');
    const inherited = source.searchParams.has('catalogue_query')
        ? new URLSearchParams(source.searchParams.get('catalogue_query')!)
        : source.searchParams;
    const query = new URLSearchParams({ source: `portfolio:${id}` });
    for (const field of levels)
        if (inherited.get(field)) query.set(field, inherited.get(field)!);
    return '/investimentos/iniciar?' + query.toString();
}

/** Preserve an explicit complementary selection while consulting its canonical public fiche. */
export function complementPreparationHref(
    pageUrl: string,
    target?: string,
): string | null {
    const params = new URL(pageUrl, 'https://portal.invalid').searchParams;
    if (
        !params.get('complement_origin') ||
        !params.get('complement_code') ||
        (target && params.get('complement_target') !== target)
    )
        return null;
    const query = new URLSearchParams();
    for (const field of [
        'complement_origin',
        'complement_code',
        'complement_target',
        'complement_territory',
        'selection_key',
    ])
        if (params.get(field)) query.set(field, params.get(field)!);
    const dossier = params.get('investment_dossier');
    return (
        (dossier &&
        /^[0-9a-f]{8}-(?:[0-9a-f]{4}-){3}[0-9a-f]{12}$/i.test(dossier)
            ? `/investimentos/${dossier}/contexto/editar`
            : '/investimentos/iniciar') +
        '?' +
        query
    );
}

/** Carry the explicitly consulted portfolio origin and search geography into the existing preparation entry. */
export function investmentPreparationHref(
    opportunity: number,
    pageUrl: string,
    origin?: string | null,
): string {
    const complementary = complementPreparationHref(
        pageUrl,
        `opportunity:${opportunity}`,
    );
    if (complementary) return complementary;
    const source = new URL(pageUrl, 'https://portal.invalid');
    const inherited = source.searchParams.has('catalogue_query')
        ? new URLSearchParams(source.searchParams.get('catalogue_query')!)
        : source.searchParams;
    const query = new URLSearchParams({ source: `opportunity:${opportunity}` });
    if (origin) query.set('from_dossier', origin);
    for (const field of levels)
        if (inherited.get(field)) query.set(field, inherited.get(field)!);
    return '/investimentos/iniciar?' + query.toString();
}

/** URL-scoped search context, never a saved investment or another browser tab. */
export function searchTerritoryHref(href: string, pageUrl: string): string {
    const base = 'https://portal.invalid';
    const source = new URL(pageUrl, base);
    const target = new URL(href, base);
    const supported = (path: string) =>
        searchRoutes.some(
            (route) => path === route || path.startsWith(`${route}/`),
        );
    if (
        target.origin !== base ||
        !supported(source.pathname) ||
        !supported(target.pathname)
    )
        return href;
    const inherited = source.searchParams.has('catalogue_query')
        ? new URLSearchParams(source.searchParams.get('catalogue_query')!)
        : source.searchParams;
    // An explicit ancestor, including an explicit empty value, overrides its descendants.
    let changed = false;
    for (const field of levels) {
        if (target.searchParams.has(field)) {
            changed ||= target.searchParams.get(field) !== inherited.get(field);
        } else if (!changed && inherited.get(field)) {
            target.searchParams.set(field, inherited.get(field)!);
        }
    }
    return target.pathname + target.search + target.hash;
}