import type { HostKind, PathKind } from './api';

/** Guess a path kind from the literal user input. The dashboard pre-fills
 *  the kind selector but the user can override (the backend trusts the
 *  selection — selecting `exact` for `/greet/:name` matches it literally). */
export function guessPathKind(raw: string): PathKind {
	if (raw.endsWith('/*')) return 'prefix';
	if (/(^|\/):[a-zA-Z_]/.test(raw)) return 'param';
	return 'exact';
}

/** Guess a host kind. Empty → any, leading "*." → wildcard, else strict. */
export function guessHostKind(raw: string): HostKind {
	if (!raw.trim()) return 'any';
	if (raw.startsWith('*.')) return 'wildcard';
	return 'strict';
}

/** Warn-not-block: does the user's selection match what we'd guess
 *  from the input? Used by the routing form for the soft mismatch
 *  hint. Returns null when no warning is needed. */
export function pathKindMismatchWarning(raw: string, kind: PathKind): string | null {
	const guessed = guessPathKind(raw);
	if (guessed === kind) return null;
	const hint =
		guessed === 'param'
			? 'this looks like a param pattern (contains `:name`)'
			: guessed === 'prefix'
				? 'this looks like a prefix pattern (ends with `/*`)'
				: 'this looks like a literal path';
	return `Selected kind is "${kind}", but ${hint}. Routing will use the selected kind.`;
}