<?php
/**
 * Admin reminder rules (docs/08 §2.9).
 *
 * @package Bookline
 */

declare( strict_types=1 );

namespace Bookline\Application\Notification;

use Bookline\Domain\Edition\NamedFeature;
use Bookline\Domain\Edition\NamedFeatureGate;
use Bookline\Domain\Edition\OpenNamedFeatureGate;
use Bookline\Domain\Notification\ReminderRule;
use Bookline\Domain\Notification\ReminderRuleRepository;
use Bookline\Domain\Shared\Clock;
use Bookline\Domain\Shared\DomainException;
use Bookline\Domain\Shared\Uuid;

/**
 * List and mutate reminder offset rules.
 *
 * @since 0.1.0
 */
final class ReminderAdminService {

	private const APPLIES = [ 'all', 'service', 'agent', 'location' ];

	private const CHANNELS = [ 'email', 'sms', 'whatsapp' ];

	/**
	 * Constructor.
	 *
	 * @param ReminderRuleRepository $rules Rules.
	 * @param Clock                  $clock Clock.
	 * @param NamedFeatureGate|null  $named Paid-plan features; open when omitted.
	 */
	public function __construct(
		private readonly ReminderRuleRepository $rules,
		private readonly Clock $clock,
		private readonly ?NamedFeatureGate $named = null,
	) {}

	/**
	 * All rules.
	 *
	 * @return array{items: list<array<string, mixed>>, total: int}
	 */
	public function list(): array {
		$items = [];
		foreach ( $this->rules->all() as $rule ) {
			$items[] = $this->to_admin_array( $rule );
		}

		return [
			'items' => $items,
			'total' => count( $items ),
		];
	}

	/**
	 * Create a rule.
	 *
	 * @param array<string, mixed> $payload Fields.
	 * @return array<string, mixed>
	 */
	public function create( array $payload ): array {
		$now  = $this->clock->now();
		$rule = new ReminderRule(
			null,
			Uuid::generate(),
			$this->name( $payload ),
			$this->template_key( $payload ),
			$this->channel( $payload ),
			$this->offset( $payload ),
			$this->applies_to( $payload ),
			$this->target_ids( $payload ),
			$this->statuses( $payload ),
			array_key_exists( 'is_enabled', $payload ) ? (bool) $payload['is_enabled'] : true,
			$now,
			$now,
		);
		$this->rules->save( $rule );

		return $this->to_admin_array( $rule );
	}

	/**
	 * Patch a rule.
	 *
	 * @param int                  $id      Id.
	 * @param array<string, mixed> $payload Fields.
	 * @return array<string, mixed>
	 *
	 * @throws DomainException When missing.
	 */
	public function update( int $id, array $payload ): array {
		$existing = $this->rules->find_by_id( $id );
		if ( null === $existing ) {
			throw new DomainException( 'reminder.not_found', 'Reminder rule not found.' );
		}

		$now  = $this->clock->now();
		$rule = new ReminderRule(
			$existing->id(),
			$existing->uuid(),
			array_key_exists( 'name', $payload ) ? $this->name( $payload ) : $existing->name(),
			array_key_exists( 'template_key', $payload ) ? $this->template_key( $payload ) : $existing->template_key(),
			array_key_exists( 'channel', $payload ) ? $this->channel( $payload ) : $existing->channel(),
			array_key_exists( 'offset_minutes', $payload ) ? $this->offset( $payload ) : $existing->offset_minutes(),
			array_key_exists( 'applies_to', $payload ) ? $this->applies_to( $payload ) : $existing->applies_to(),
			array_key_exists( 'target_ids', $payload ) ? $this->target_ids( $payload ) : $existing->target_ids(),
			array_key_exists( 'booking_statuses', $payload ) ? $this->statuses( $payload ) : $existing->booking_statuses(),
			array_key_exists( 'is_enabled', $payload ) ? (bool) $payload['is_enabled'] : $existing->is_enabled(),
			$existing->created_at(),
			$now,
		);
		$this->rules->save( $rule );

		return $this->to_admin_array( $rule );
	}

	/**
	 * Delete a rule.
	 *
	 * @param int $id Id.
	 * @return array{deleted: bool}
	 *
	 * @throws DomainException When missing.
	 */
	public function delete( int $id ): array {
		if ( null === $this->rules->find_by_id( $id ) ) {
			throw new DomainException( 'reminder.not_found', 'Reminder rule not found.' );
		}
		$this->rules->delete( $id );

		return [ 'deleted' => true ];
	}

	/**
	 * Map a rule to the admin payload.
	 *
	 * @param ReminderRule $rule Rule.
	 * @return array<string, mixed>
	 */
	private function to_admin_array( ReminderRule $rule ): array {
		return [
			'id'               => $rule->id(),
			'name'             => $rule->name(),
			'template_key'     => $rule->template_key(),
			'channel'          => $rule->channel(),
			'offset_minutes'   => $rule->offset_minutes(),
			'applies_to'       => $rule->applies_to(),
			'target_ids'       => $rule->target_ids(),
			'booking_statuses' => $rule->booking_statuses(),
			'is_enabled'       => $rule->is_enabled(),
		];
	}

	/**
	 * Rule name.
	 *
	 * @param array<string, mixed> $payload Payload.
	 */
	private function name( array $payload ): string {
		$name = trim( (string) ( $payload['name'] ?? '' ) );
		return '' !== $name ? $name : 'Reminder';
	}

	/**
	 * Template key.
	 *
	 * @param array<string, mixed> $payload Payload.
	 */
	private function template_key( array $payload ): string {
		$key = strtolower( trim( (string) ( $payload['template_key'] ?? 'booking.reminder.customer' ) ) );
		if ( 1 !== preg_match( '/^[a-z0-9._-]+$/', $key ) ) {
			return 'booking.reminder.customer';
		}
		return $key;
	}

	/**
	 * Channel id.
	 *
	 * @param array<string, mixed> $payload Payload.
	 */
	private function channel( array $payload ): string {
		$channel = strtolower( (string) ( $payload['channel'] ?? 'email' ) );
		$channel = in_array( $channel, self::CHANNELS, true ) ? $channel : 'email';
		if ( in_array( $channel, [ 'sms', 'whatsapp' ], true ) ) {
			$this->named_features()->assert_allows( NamedFeature::SmsWhatsapp );
		}
		return $channel;
	}

	/**
	 * Named-feature gate (directory zip is open).
	 */
	private function named_features(): NamedFeatureGate {
		return $this->named ?? new OpenNamedFeatureGate();
	}

	/**
	 * Offset in minutes.
	 *
	 * @param array<string, mixed> $payload Payload.
	 */
	private function offset( array $payload ): int {
		return (int) ( $payload['offset_minutes'] ?? -1440 );
	}

	/**
	 * Scope.
	 *
	 * @param array<string, mixed> $payload Payload.
	 */
	private function applies_to( array $payload ): string {
		$applies = strtolower( (string) ( $payload['applies_to'] ?? 'all' ) );
		return in_array( $applies, self::APPLIES, true ) ? $applies : 'all';
	}

	/**
	 * Target entity ids.
	 *
	 * @param array<string, mixed> $payload Payload.
	 * @return list<int>|null
	 */
	private function target_ids( array $payload ): ?array {
		if ( ! isset( $payload['target_ids'] ) || ! is_array( $payload['target_ids'] ) ) {
			return null;
		}
		$ids = [];
		foreach ( $payload['target_ids'] as $id ) {
			$n = (int) $id;
			if ( $n > 0 ) {
				$ids[] = $n;
			}
		}
		return [] === $ids ? null : array_values( array_unique( $ids ) );
	}

	/**
	 * Booking status allow-list.
	 *
	 * @param array<string, mixed> $payload Payload.
	 * @return list<string>|null
	 */
	private function statuses( array $payload ): ?array {
		if ( ! isset( $payload['booking_statuses'] ) || ! is_array( $payload['booking_statuses'] ) ) {
			return null;
		}
		$out = [];
		foreach ( $payload['booking_statuses'] as $status ) {
			if ( is_string( $status ) && preg_match( '/^[a-z_]+$/', $status ) ) {
				$out[] = $status;
			}
		}
		return [] === $out ? null : array_values( array_unique( $out ) );
	}
}