<?php
/**
 * Resolves booking-form catalogue scope for sessions and public reads.
 *
 * @package Bookline
 */

declare( strict_types=1 );

namespace Bookline\Application\BookingForm;

use Bookline\Domain\Agent\Agent;
use Bookline\Domain\Agent\AgentRepository;
use Bookline\Domain\BookingForm\BookingForm;
use Bookline\Domain\BookingForm\BookingFormRepository;
use Bookline\Domain\BookingForm\BookingFormStatus;
use Bookline\Domain\Location\Location;
use Bookline\Domain\Location\LocationRepository;
use Bookline\Domain\Service\Service;
use Bookline\Domain\Service\ServiceRepository;
use Bookline\Domain\Shared\DomainException;

/**
 * Filters catalogue entities to a form's configured scope.
 *
 * @since 0.1.0
 */
final class BookingFormScope {

	/**
	 * Constructor.
	 *
	 * @param BookingFormRepository $forms    Forms.
	 * @param ServiceRepository     $services Services.
	 * @param AgentRepository       $agents   Agents.
	 * @param LocationRepository    $locations Locations.
	 */
	public function __construct(
		private readonly BookingFormRepository $forms,
		private readonly ServiceRepository $services,
		private readonly AgentRepository $agents,
		private readonly LocationRepository $locations,
	) {}

	/**
	 * Load a form for public catalogue scoping.
	 *
	 * Inactive forms are ignored so callers fall back to the full catalogue.
	 *
	 * @param int $form_id Form id.
	 */
	public function active_form( int $form_id ): ?BookingForm {
		if ( $form_id <= 0 ) {
			return null;
		}
		$form = $this->forms->find_by_id( $form_id );
		if ( null === $form || BookingFormStatus::Active !== $form->status() ) {
			return null;
		}
		return $form;
	}

	/**
	 * Ensure a form exists and accepts new sessions.
	 *
	 * @param int $form_id Form id.
	 *
	 * @throws DomainException When missing or inactive.
	 */
	public function assert_bookable( int $form_id ): void {
		if ( $form_id <= 0 ) {
			return;
		}
		$form = $this->forms->find_by_id( $form_id );
		if ( null === $form ) {
			throw new DomainException( 'booking_form.not_found', 'Booking form not found.' );
		}
		if ( BookingFormStatus::Active !== $form->status() ) {
			throw new DomainException( 'booking_form.inactive', 'This booking form is not accepting bookings.' );
		}
	}

	/**
	 * Whether a service is offered on this form.
	 *
	 * @param BookingForm|null $form    Form (null = unrestricted).
	 * @param Service          $service Service.
	 */
	public function service_allowed( ?BookingForm $form, Service $service ): bool {
		if ( null === $form ) {
			return true;
		}
		$service_ids  = $form->service_ids();
		$category_ids = $form->category_ids();
		if ( ( null === $service_ids || [] === $service_ids ) && ( null === $category_ids || [] === $category_ids ) ) {
			return true;
		}
		$id = $service->id();
		if ( null !== $id && null !== $service_ids && [] !== $service_ids && in_array( $id, $service_ids, true ) ) {
			return true;
		}
		$category_id = $service->category_id();
		if ( null !== $category_id && null !== $category_ids && [] !== $category_ids && in_array( $category_id, $category_ids, true ) ) {
			return true;
		}
		return false;
	}

	/**
	 * Whether an agent is offered on this form.
	 *
	 * @param BookingForm|null $form  Form.
	 * @param Agent            $agent Agent.
	 */
	public function agent_allowed( ?BookingForm $form, Agent $agent ): bool {
		if ( null === $form ) {
			return true;
		}
		$ids = $form->agent_ids();
		if ( null === $ids || [] === $ids ) {
			return true;
		}
		$id = $agent->id();
		return null !== $id && in_array( $id, $ids, true );
	}

	/**
	 * Whether a location is offered on this form.
	 *
	 * @param BookingForm|null $form     Form.
	 * @param Location         $location Location.
	 */
	public function location_allowed( ?BookingForm $form, Location $location ): bool {
		if ( null === $form ) {
			return true;
		}
		$ids = $form->location_ids();
		if ( null === $ids || [] === $ids ) {
			return true;
		}
		$id = $location->id();
		return null !== $id && in_array( $id, $ids, true );
	}

	/**
	 * Count active agents eligible for the form.
	 *
	 * @param BookingForm|null $form Form.
	 */
	public function count_eligible_agents( ?BookingForm $form ): int {
		return $this->count_eligible_agents_for_lists( $form?->agent_ids() );
	}

	/**
	 * Count active locations eligible for the form.
	 *
	 * @param BookingForm|null $form Form.
	 */
	public function count_eligible_locations( ?BookingForm $form ): int {
		return $this->count_eligible_locations_for_lists( $form?->location_ids() );
	}

	/**
	 * Active agents for an id list (null = all active).
	 *
	 * @param list<int>|null $scoped_ids Agent ids.
	 * @return list<array<string, mixed>>
	 */
	public function agents_for_lists( ?array $scoped_ids ): array {
		$out = [];
		foreach ( $this->agents->find_active( 100, 0 ) as $agent ) {
			if ( ! $this->id_allowed( $scoped_ids, $agent->id() ) ) {
				continue;
			}
			$out[] = [
				'id'         => $agent->id(),
				'name'       => $agent->display_name(),
				'bio'        => $agent->bio(),
				'avatar_url' => null,
			];
		}
		return $out;
	}

	/**
	 * Active locations for an id list (null = all active).
	 *
	 * @param list<int>|null $scoped_ids Location ids.
	 * @return list<array<string, mixed>>
	 */
	public function locations_for_lists( ?array $scoped_ids ): array {
		$out = [];
		foreach ( $this->locations->find_active( 100, 0 ) as $location ) {
			if ( ! $this->id_allowed( $scoped_ids, $location->id() ) ) {
				continue;
			}
			$out[] = [
				'id'            => $location->id(),
				'name'          => $location->name(),
				'address_line1' => $location->address_line1(),
				'city'          => $location->city(),
				'postcode'      => $location->postcode(),
				'country'       => $location->country(),
			];
		}
		return $out;
	}

	/**
	 * Count active agents eligible for scoped id lists.
	 *
	 * @param list<int>|null $agent_ids Agent ids.
	 */
	public function count_eligible_agents_for_lists( ?array $agent_ids ): int {
		return count( $this->agents_for_lists( $agent_ids ) );
	}

	/**
	 * Count active locations eligible for scoped id lists.
	 *
	 * @param list<int>|null $location_ids Location ids.
	 */
	public function count_eligible_locations_for_lists( ?array $location_ids ): int {
		return count( $this->locations_for_lists( $location_ids ) );
	}

	/**
	 * Whether an entity id is allowed by an optional scope list.
	 *
	 * @param list<int>|null $scoped_ids Scope list.
	 * @param int|null       $id         Entity id.
	 */
	private function id_allowed( ?array $scoped_ids, ?int $id ): bool {
		if ( null === $scoped_ids || [] === $scoped_ids ) {
			return true;
		}
		return null !== $id && in_array( $id, $scoped_ids, true );
	}

	/**
	 * Active agents for a form's scope, formatted for step descriptors.
	 *
	 * @param BookingForm|null $form Form.
	 * @return list<array<string, mixed>>
	 */
	public function agents_for_descriptor( ?BookingForm $form ): array {
		return $this->agents_for_lists( $form?->agent_ids() );
	}

	/**
	 * Active locations for a form's scope, formatted for step descriptors.
	 *
	 * @param BookingForm|null $form Form.
	 * @return list<array<string, mixed>>
	 */
	public function locations_for_descriptor( ?BookingForm $form ): array {
		return $this->locations_for_lists( $form?->location_ids() );
	}
}