<?php

namespace ACP\Search;

use AC\Registerable;
use ACP\Search\Query\Bindings;
use LogicException;

abstract class Query implements Registerable
{

    /**
     * @var Bindings[]
     */
    protected $bindings;

    /**
     * @param Bindings[] $bindings
     */
    public function __construct(array $bindings)
    {
        $this->bindings = $bindings;

        $this->validate_bindings();
    }

    /**
     * @throws LogicException
     */
    private function validate_bindings(): void
    {
        foreach ($this->bindings as $bindings) {
            if ( ! $bindings instanceof Bindings) {
                throw new LogicException('Expected Bindings object.');
            }
        }
    }

    protected function get_meta_query(): array
    {
        $meta_query = [];

        foreach ($this->bindings as $binding) {
            $meta_query[] = $binding->get_meta_query();
        }

        $meta_query = array_filter($meta_query);

        if ($meta_query) {
            $meta_query['relation'] = 'AND';
        }

        return $meta_query;
    }

}