<?php
/**
 * Media library uploads and deletions (#5).
 *
 * @package ActivityLog404
 */

namespace ActivityLog404\Events;

use ActivityLog404\EventLogger;

defined( 'ABSPATH' ) || exit;

/**
 * An attachment is a post, but EventLogger has always left attachments out of
 * its post events (an upload would otherwise read as "Attachment created"
 * and every metadata write as an update). So the media library gets its own
 * two rows, from core's attachment-specific hooks: `add_attachment` once the
 * attachment exists, `delete_attachment` while it still does. Both fire for
 * every writer -- the media screen, the block editor, REST, a plugin's
 * sideload -- which is the point.
 *
 * What a row keeps: the file's name (bounded) and MIME type. The file itself,
 * its EXIF data and its caption are never read. Editing an attachment's title
 * or alt text is a named deferral (docs/event-coverage.md).
 */
final class MediaEvents {

	public const UPLOADED = 'media_uploaded';
	public const DELETED  = 'media_deleted';

	/** How many characters of a file name a row keeps. */
	public const FILE_NAME_LENGTH = 200;

	/**
	 * @return array<string, string> Event type => label for the log's filter.
	 */
	public static function event_types(): array {
		return array(
			self::UPLOADED => 'Media Uploaded',
			self::DELETED  => 'Media Deleted',
		);
	}

	public static function register(): void {
		add_action( 'add_attachment', array( __CLASS__, 'log_uploaded' ) );
		add_action( 'delete_attachment', array( __CLASS__, 'log_deleted' ) );
	}

	/**
	 * @param int $post_id The attachment.
	 */
	public static function log_uploaded( int $post_id ): void {
		self::log( self::UPLOADED, 'Media "%s" uploaded', $post_id );
	}

	/**
	 * @param int $post_id The attachment.
	 */
	public static function log_deleted( int $post_id ): void {
		self::log( self::DELETED, 'Media "%s" deleted', $post_id );
	}

	/**
	 * @param string $type    Event type.
	 * @param string $summary Summary format; the file name fills it.
	 * @param int    $post_id The attachment.
	 */
	private static function log( string $type, string $summary, int $post_id ): void {
		$post = get_post( $post_id );
		if ( ! $post || 'attachment' !== $post->post_type ) {
			return;
		}

		$file = get_post_meta( $post_id, '_wp_attached_file', true );
		$name = is_string( $file ) && '' !== $file ? wp_basename( $file ) : (string) $post->post_title;
		$name = EventLogger::bounded( $name, self::FILE_NAME_LENGTH );

		EventLogger::log(
			$type,
			sprintf( $summary, $name ),
			'attachment',
			$post_id,
			array(
				'file'      => $name,
				'mime_type' => EventLogger::bounded( (string) $post->post_mime_type, 100 ),
			)
		);
	}
}