<?php
/**
 * Audit check: what rights are being declared?
 *
 * @package AIBlackout
 */

namespace AIBlackout\Audit\Checks;

use AIBlackout\Audit\Check;
use AIBlackout\Audit\Result;
use AIBlackout\Declarations\ContentSignals;
use AIBlackout\Declarations\History;
use AIBlackout\Declarations\MetaTags;
use AIBlackout\Declarations\Tdmrep;

defined( 'ABSPATH' ) || exit;

/**
 * Reports the legal declarations, and how long they have stood.
 *
 * @since 1.0.0
 */
class DeclarationsCheck implements Check {

	/**
	 * TDM reservation.
	 *
	 * @var Tdmrep
	 */
	private $tdmrep;

	/**
	 * Content Signals declaration.
	 *
	 * @var ContentSignals
	 */
	private $signals;

	/**
	 * The noai and noimageai directives.
	 *
	 * @var MetaTags
	 */
	private $meta;

	/**
	 * Declaration history.
	 *
	 * @var History
	 */
	private $history;

	/**
	 * Constructor.
	 *
	 * @param Tdmrep         $tdmrep  TDM reservation.
	 * @param ContentSignals $signals Content Signals declaration.
	 * @param MetaTags       $meta    The noai and noimageai directives.
	 * @param History        $history Declaration history.
	 */
	public function __construct( Tdmrep $tdmrep, ContentSignals $signals, MetaTags $meta, History $history ) {
		$this->tdmrep  = $tdmrep;
		$this->signals = $signals;
		$this->meta    = $meta;
		$this->history = $history;
	}

	/**
	 * Returns the check identifier.
	 *
	 * @return string Identifier.
	 */
	public function get_id(): string {
		return 'declarations';
	}

	/**
	 * Whether a loopback request is required.
	 *
	 * @return bool False.
	 */
	public function needs_loopback(): bool {
		return false;
	}

	/**
	 * Runs the check.
	 *
	 * @return Result The finding.
	 */
	public function run(): Result {
		$label     = __( 'Legal declarations', 'ai-blackout' );
		$published = array();

		if ( $this->tdmrep->is_enabled() ) {
			$published[] = __( 'a reservation of text and data mining rights', 'ai-blackout' );
		}

		if ( '' !== $this->signals->build_block() ) {
			$published[] = __( 'content signals in robots.txt', 'ai-blackout' );
		}

		if ( $this->meta->is_enabled() ) {
			$published[] = __( 'noai and noimageai directives', 'ai-blackout' );
		}

		$since  = $this->history->first_published( Tdmrep::TYPE );
		$detail = array(
			'tdmrep_enabled'  => $this->tdmrep->is_enabled(),
			'tdmrep_url'      => $this->tdmrep->get_url(),
			'tdmrep_document' => $this->tdmrep->preview(),
			'signals'         => $this->signals->get_signals(),
			'directives'      => $this->meta->get_directives(),
			'first_published' => $since,
			'entries'         => count( $this->history->all() ),
		);

		if ( aiblackout_is_disabled() ) {
			return new Result(
				$this->get_id(),
				$label,
				Result::INACTIVE,
				__( 'AI Blackout is switched off by the AIBLACKOUT_DISABLE setting in wp-config.php.', 'ai-blackout' ),
				__( 'No declarations are being published. Your previously recorded declaration history is kept.', 'ai-blackout' ),
				__( 'Remove the AIBLACKOUT_DISABLE line from wp-config.php to publish them again.', 'ai-blackout' ),
				$detail
			);
		}

		if ( empty( $published ) ) {
			return new Result(
				$this->get_id(),
				$label,
				Result::INACTIVE,
				__( 'You are not declaring any rights over your content.', 'ai-blackout' ),
				__( 'Blocking a crawler stops it taking your content today. A declaration states, in a form a court can read, that you never gave permission. That is what matters if content has already been taken.', 'ai-blackout' ),
				__( 'Turn on the rights reservation. It publishes a legal statement, changes nothing a visitor sees, and cannot affect your search ranking.', 'ai-blackout' ),
				$detail
			);
		}

		return new Result(
			$this->get_id(),
			$label,
			Result::DECLARED,
			sprintf(
				/* translators: %s: Comma-separated list of published declarations. */
				__( 'You are publishing %s.', 'ai-blackout' ),
				$this->join( $published )
			),
			$this->describe_standing( $since ),
			'',
			$detail
		);
	}

	/**
	 * Explains what the declaration is worth and since when.
	 *
	 * @param int|null $since Unix timestamp of first publication.
	 * @return string Human-readable explanation.
	 */
	private function describe_standing( ?int $since ): string {
		$base = __( 'This does not block anything. Under EU copyright law a machine-readable reservation removes the permission that would otherwise let anyone mine your content for AI training, so scraping it becomes an infringement rather than something allowed by default.', 'ai-blackout' );

		if ( null === $since ) {
			return $base;
		}

		$days = (int) floor( ( time() - $since ) / DAY_IN_SECONDS );

		if ( $days < 1 ) {
			return $base . ' ' . __( 'It was published today. It applies from now on, not to anything taken before.', 'ai-blackout' );
		}

		return $base . ' ' . sprintf(
			/* translators: 1: Number of days, 2: Date the declaration was first published. */
			_n(
				'It has stood for %1$d day, since %2$s. It applies to what happened after that date, not before.',
				'It has stood for %1$d days, since %2$s. It applies to what happened after that date, not before.',
				$days,
				'ai-blackout'
			),
			$days,
			date_i18n( get_option( 'date_format' ), $since )
		);
	}

	/**
	 * Joins a list into a readable sentence fragment.
	 *
	 * @param string[] $items Items to join.
	 * @return string Joined string.
	 */
	private function join( array $items ): string {
		if ( count( $items ) < 2 ) {
			return (string) reset( $items );
		}

		$last = array_pop( $items );

		return implode( ', ', $items ) . __( ' and ', 'ai-blackout' ) . $last;
	}
}