import type { AvailableModel } from "./types.js";

function uniqueMatch(matches: readonly AvailableModel[]): AvailableModel | undefined {
  return matches.length === 1 ? matches[0] : undefined;
}

export function resolveModel(requested: string, available: readonly AvailableModel[]): AvailableModel | undefined {
  const query = requested.trim().toLowerCase();
  if (!query) return undefined;

  const exact = available.filter((model) => model.id.toLowerCase() === query);
  if (exact.length) return uniqueMatch(exact);

  const aliases = available.filter((model) => {
    const suffix = model.id.split("/").at(-1)?.toLowerCase();
    return suffix === query || model.name?.toLowerCase() === query;
  });
  if (aliases.length) return uniqueMatch(aliases);

  return uniqueMatch(available.filter((model) => model.id.toLowerCase().includes(query)));
}