<?php
// SPDX-License-Identifier: GPL-3.0-or-later
declare(strict_types=1);

namespace Aiwend\Provider;

/**
 * Which models a module's "AI connection and model" picker offers for one connection.
 *
 * A picker shows a bounded number of models, but a provider account can list far more (an OpenAI account lists well over a hundred IDs, in
 * alphabetical order), so a plain "first N" hides every model whose ID sorts late, including the cheap current ones. The model the owner chose
 * as the connection's default and the model that passed a test message are therefore always offered, first; the rest follow in list order up to
 * the bound. Pure function of its arguments (unit-tested without WordPress).
 */
final class ModelPicker
{
    public const LIMIT = 60;

    /**
     * @param list<array<string, mixed>> $chatModels models in list order, each with a string 'id'
     * @return list<array<string, mixed>>
     */
    public static function choose(array $chatModels, ?string $default, ?string $tested, int $limit = self::LIMIT): array
    {
        $first = [];
        foreach ([$default, $tested] as $wanted) {
            if ($wanted === null || $wanted === '') {
                continue;
            }
            foreach ($chatModels as $model) {
                if (($model['id'] ?? null) === $wanted) {
                    $first[$wanted] = $model;
                    break;
                }
            }
        }
        $rest = array_values(array_filter($chatModels, static fn(array $m): bool => !isset($first[(string) ($m['id'] ?? '')])));
        return array_slice(array_merge(array_values($first), $rest), 0, max($limit, count($first)));
    }
}