documentation}. Use
 * the `===` operator for testing the return value of this function.
 *
 * @since 2.1.0
 * @since 5.1.0 Return value added to indicate success or failure.
 * @since 5.7.0 Functionality moved to _wp_cron() to which this becomes a wrapper.
 *
 * @return bool|int|void On success an integer indicating number of events spawned (0 indicates no
 *                       events needed to be spawned), false if spawning fails for one or more events or
 *                       void if the function registered _wp_cron() to run on the action.
 */
function wp_cron() {
	if ( did_action( 'wp_loaded' ) ) {
		return _wp_cron();
	}

	add_action( 'wp_loaded', '_wp_cron', 20 );
}

/**
 * Runs scheduled callbacks or spawns cron for all scheduled events.
 *
 * Warning: This function may return Boolean FALSE, but may also return a non-Boolean
 * value which evaluates to FALSE. For information about casting to booleans see the
 * {@link https://www.php.net/manual/en/language.types.boolean.php PHP documentation}. Use
 * the `===` operator for testing the return value of this function.
 *
 * @since 5.7.0
 * @access private
 *
 * @return int|false On success an integer indicating number of events spawned (0 indicates no
 *                   events needed to be spawned), false if spawning fails for one or more events.
 */
function _wp_cron() {
	// Prevent infinite loops caused by lack of wp-cron.php.
	if ( str_contains( $_SERVER['REQUEST_URI'], '/wp-cron.php' ) || ( defined( 'DISABLE_WP_CRON' ) && DISABLE_WP_CRON ) ) {
		return 0;
	}

	$crons = wp_get_ready_cron_jobs();
	if ( empty( $crons ) ) {
		return 0;
	}

	$gmt_time = microtime( true );
	$keys     = array_keys( $crons );
	if ( isset( $keys[0] ) && $keys[0] > $gmt_time ) {
		return 0;
	}

	$schedules = wp_get_schedules();
	$results   = array();
	foreach ( $crons as $timestamp => $cronhooks ) {
		if ( $timestamp > $gmt_time ) {
			break;
		}
		foreach ( (array) $cronhooks as $hook => $args ) {
			if ( isset( $schedules[ $hook ]['callback'] ) && ! call_user_func( $schedules[ $hook ]['callback'] ) ) {
				continue;
			}
			$results[] = spawn_cron( $gmt_time );
			break 2;
		}
	}

	if ( in_array( false, $results, true ) ) {
		return false;
	}
	return count( $results );
}

/**
 * Retrieves supported event recurrence schedules.
 *
 * The default supported recurrences are 'hourly', 'twicedaily', 'daily', and 'weekly'.
 * A plugin may add more by hooking into the {@see 'cron_schedules'} filter.
 * The filter accepts an array of arrays. The outer array has a key that is the name
 * of the schedule, for example 'monthly'. The value is an array with two keys,
 * one is 'interval' and the other is 'display'.
 *
 * The 'interval' is a number in seconds of when the cron job should run.
 * So for 'hourly' the time is `HOUR_IN_SECONDS` (60 * 60 or 3600). For 'monthly',
 * the value would be `MONTH_IN_SECONDS` (30 * 24 * 60 * 60 or 2592000).
 *
 * The 'display' is the description. For the 'monthly' key, the 'display'
 * would be `__( 'Once Monthly' )`.
 *
 * For your plugin, you will be passed an array. You can easily add your
 * schedule by doing the following.
 *
 *     // Filter parameter variable name is 'array'.
 *     $array['monthly'] = array(
 *         'interval' => MONTH_IN_SECONDS,
 *         'display'  => __( 'Once Monthly' )
 *     );
 *
 * @since 2.1.0
 * @since 5.4.0 The 'weekly' schedule was added.
 *
 * @return array {
 *     The array of cron schedules keyed by the schedule name.
 *
 *     @type array ...$0 {
 *         Cron schedule information.
 *
 *         @type int    $interval The schedule interval in seconds.
 *         @type string $display  The schedule display name.
 *     }
 * }
 */
function wp_get_schedules() {
	$schedules = array(
		'hourly'     => array(
			'interval' => HOUR_IN_SECONDS,
			'display'  => __( 'Once Hourly' ),
		),
		'twicedaily' => array(
			'interval' => 12 * HOUR_IN_SECONDS,
			'display'  => __( 'Twice Daily' ),
		),
		'daily'      => array(
			'interval' => DAY_IN_SECONDS,
			'display'  => __( 'Once Daily' ),
		),
		'weekly'     => array(
			'interval' => WEEK_IN_SECONDS,
			'display'  => __( 'Once Weekly' ),
		),
	);

	/**
	 * Filters the non-default cron schedules.
	 *
	 * @since 2.1.0
	 *
	 * @param array $new_schedules {
	 *     An array of non-default cron schedules keyed by the schedule name. Default empty array.
	 *
	 *     @type array ...$0 {
	 *         Cron schedule information.
	 *
	 *         @type int    $interval The schedule interval in seconds.
	 *         @type string $display  The schedule display name.
	 *     }
	 * }
	 */
	return array_merge( apply_filters( 'cron_schedules', array() ), $schedules );
}

/**
 * Retrieves the name of the recurrence schedule for an event.
 *
 * @see wp_get_schedules() for available schedules.
 *
 * @since 2.1.0
 * @since 5.1.0 {@see 'get_schedule'} filter added.
 *
 * @param string $hook Action hook to identify the event.
 * @param array  $args Optional. Arguments passed to the event's callback function.
 *                     Default empty array.
 * @return string|false Schedule name on success, false if no schedule.
 */
function wp_get_schedule( $hook, $args = array() ) {
	$schedule = false;
	$event    = wp_get_scheduled_event( $hook, $args );

	if ( $event ) {
		$schedule = $event->schedule;
	}

	/**
	 * Filters the schedule name for a hook.
	 *
	 * @since 5.1.0
	 *
	 * @param string|false $schedule Schedule for the hook. False if not found.
	 * @param string       $hook     Action hook to execute when cron is run.
	 * @param array        $args     Arguments to pass to the hook's callback function.
	 */
	return apply_filters( 'get_schedule', $schedule, $hook, $args );
}

/**
 * Retrieves cron jobs ready to be run.
 *
 * Returns the results of _get_cron_array() limited to events ready to be run,
 * ie, with a timestamp in the past.
 *
 * @since 5.1.0
 *
 * @return array[] Array of cron job arrays ready to be run.
 */
function wp_get_ready_cron_jobs() {
	/**
	 * Filter to preflight or hijack retrieving ready cron jobs.
	 *
	 * Returning an array will short-circuit the normal retrieval of ready
	 * cron jobs, causing the function to return the filtered value instead.
	 *
	 * @since 5.1.0
	 *
	 * @param null|array[] $pre Array of ready cron tasks to return instead. Default null
	 *                          to continue using results from _get_cron_array().
	 */
	$pre = apply_filters( 'pre_get_ready_cron_jobs', null );

	if ( null !== $pre ) {
		return $pre;
	}

	$crons    = _get_cron_array();
	$gmt_time = microtime( true );
	$results  = array();

	foreach ( $crons as $timestamp => $cronhooks ) {
		if ( $timestamp > $gmt_time ) {
			break;
		}

		$results[ $timestamp ] = $cronhooks;
	}

	return $results;
}

//
// Private functions.
//

/**
 * Retrieves cron info array option.
 *
 * @since 2.1.0
 * @since 6.1.0 Return type modified to consistently return an array.
 * @access private
 *
 * @return array[] Array of cron events.
 */
function _get_cron_array() {
	$cron = get_option( 'cron' );
	if ( ! is_array( $cron ) ) {
		return array();
	}

	if ( ! isset( $cron['version'] ) ) {
		$cron = _upgrade_cron_array( $cron );
	}

	unset( $cron['version'] );

	return $cron;
}

/**
 * Updates the cron option with the new cron array.
 *
 * @since 2.1.0
 * @since 5.1.0 Return value modified to outcome of update_option().
 * @since 5.7.0 The `$wp_error` parameter was added.
 *
 * @access private
 *
 * @param array[] $cron     Array of cron info arrays from _get_cron_array().
 * @param bool    $wp_error Optional. Whether to return a WP_Error on failure. Default false.
 * @return bool|WP_Error True if cron array updated. False or WP_Error on failure.
 */
function _set_cron_array( $cron, $wp_error = false ) {
	if ( ! is_array( $cron ) ) {
		$cron = array();
	}

	$cron['version'] = 2;
	$result          = update_option( 'cron', $cron );

	if ( $wp_error && ! $result ) {
		return new WP_Error(
			'could_not_set',
			__( 'The cron event list could not be saved.' )
		);
	}

	return $result;
}

/**
 * Upgrades a cron info array.
 *
 * This function upgrades the cron info array to version 2.
 *
 * @since 2.1.0
 * @access private
 *
 * @param array $cron Cron info array from _get_cron_array().
 * @return array An upgraded cron info array.
 */
function _upgrade_cron_array( $cron ) {
	if ( isset( $cron['version'] ) && 2 == $cron['version'] ) {
		return $cron;
	}

	$new_cron = array();

	foreach ( (array) $cron as $timestamp => $hooks ) {
		foreach ( (array) $hooks as $hook => $args ) {
			$key                                     = md5( serialize( $args['args'] ) );
			$new_cron[ $timestamp ][ $hook ][ $key ] = $args;
		}
	}

	$new_cron['version'] = 2;
	update_option( 'cron', $new_cron );
	return $new_cron;
}
 Checks if a given request has access to editing media.
	 *
	 * @since 5.5.0
	 *
	 * @param WP_REST_Request $request Full details about the request.
	 * @return true|WP_Error True if the request has read access, WP_Error object otherwise.
	 */
	public function edit_media_item_permissions_check( $request ) {
		if ( ! current_user_can( 'upload_files' ) ) {
			return new WP_Error(
				'rest_cannot_edit_image',
				__( 'Sorry, you are not allowed to upload media on this site.' ),
				array( 'status' => rest_authorization_required_code() )
			);
		}

		return $this->update_item_permissions_check( $request );
	}

	/**
	 * Applies edits to a media item and creates a new attachment record.
	 *
	 * @since 5.5.0
	 *
	 * @param WP_REST_Request $request Full details about the request.
	 * @return WP_REST_Response|WP_Error Response object on success, WP_Error object on failure.
	 */
	public function edit_media_item( $request ) {
		require_once ABSPATH . 'wp-admin/includes/image.php';

		$attachment_id = $request['id'];

		// This also confirms the attachment is an image.
		$image_file = wp_get_original_image_path( $attachment_id );
		$image_meta = wp_get_attachment_metadata( $attachment_id );

		if (
			! $image_meta ||
			! $image_file ||
			! wp_image_file_matches_image_meta( $request['src'], $image_meta, $attachment_id )
		) {
			return new WP_Error(
				'rest_unknown_attachment',
				__( 'Unable to get meta information for file.' ),
				array( 'status' => 404 )
			);
		}

		$supported_types = array( 'image/jpeg', 'image/png', 'image/gif', 'image/webp' );
		$mime_type       = get_post_mime_type( $attachment_id );
		if ( ! in_array( $mime_type, $supported_types, true ) ) {
			return new WP_Error(
				'rest_cannot_edit_file_type',
				__( 'This type of file cannot be edited.' ),
				array( 'status' => 400 )
			);
		}

		// The `modifiers` param takes precedence over the older format.
		if ( isset( $request['modifiers'] ) ) {
			$modifiers = $request['modifiers'];
		} else {
			$modifiers = array();

			if ( ! empty( $request['rotation'] ) ) {
				$modifiers[] = array(
					'type' => 'rotate',
					'args' => array(
						'angle' => $request['rotation'],
					),
				);
			}

			if ( isset( $request['x'], $request['y'], $request['width'], $request['height'] ) ) {
				$modifiers[] = array(
					'type' => 'crop',
					'args' => array(
						'left'   => $request['x'],
						'top'    => $request['y'],
						'width'  => $request['width'],
						'height' => $request['height'],
					),
				);
			}

			if ( 0 === count( $modifiers ) ) {
				return new WP_Error(
					'rest_image_not_edited',
					__( 'The image was not edited. Edit the image before applying the changes.' ),
					array( 'status' => 400 )
				);
			}
		}

		/*
		 * If the file doesn't exist, attempt a URL fopen on the src link.
		 * This can occur with certain file replication plugins.
		 * Keep the original file path to get a modified name later.
		 */
		$image_file_to_edit = $image_file;
		if ( ! file_exists( $image_file_to_edit ) ) {
			$image_file_to_edit = _load_image_to_edit_path( $attachment_id );
		}

		$image_editor = wp_get_image_editor( $image_file_to_edit );

		if ( is_wp_error( $image_editor ) ) {
			return new WP_Error(
				'rest_unknown_image_file_type',
				__( 'Unable to edit this image.' ),
				array( 'status' => 500 )
			);
		}

		foreach ( $modifiers as $modifier ) {
			$args = $modifier['args'];
			switch ( $modifier['type'] ) {
				case 'rotate':
					// Rotation direction: clockwise vs. counter clockwise.
					$rotate = 0 - $args['angle'];

					if ( 0 !== $rotate ) {
						$result = $image_editor->rotate( $rotate );

						if ( is_wp_error( $result ) ) {
							return new WP_Error(
								'rest_image_rotation_failed',
								__( 'Unable to rotate this image.' ),
								array( 'status' => 500 )
							);
						}
					}

					break;

				case 'crop':
					$size = $image_editor->get_size();

					$crop_x = round( ( $size['width'] * $args['left'] ) / 100.0 );
					$crop_y = round( ( $size['height'] * $args['top'] ) / 100.0 );
					$width  = round( ( $size['width'] * $args['width'] ) / 100.0 );
					$height = round( ( $size['height'] * $args['height'] ) / 100.0 );

					if ( $size['width'] !== $width && $size['height'] !== $height ) {
						$result = $image_editor->crop( $crop_x, $crop_y, $width, $height );

						if ( is_wp_error( $result ) ) {
							return new WP_Error(
								'rest_image_crop_failed',
								__( 'Unable to crop this image.' ),
								array( 'status' => 500 )
							);
						}
					}

					break;

			}
		}

		// Calculate the file name.
		$image_ext  = pathinfo( $image_file, PATHINFO_EXTENSION );
		$image_name = wp_basename( $image_file, ".{$image_ext}" );

		/*
		 * Do not append multiple `-edited` to the file name.
		 * The user may be editing a previously edited image.
		 */
		if ( preg_match( '/-edited(-\d+)?$/', $image_name ) ) {
			// Remove any `-1`, `-2`, etc. `wp_unique_filename()` will add the proper number.
			$image_name = preg_replace( '/-edited(-\d+)?$/', '-edited', $image_name );
		} else {
			// Append `-edited` before the extension.
			$image_name .= '-edited';
		}

		$filename = "{$image_name}.{$image_ext}";

		// Create the uploads sub-directory if needed.
		$uploads = wp_upload_dir();

		// Make the file name unique in the (new) upload directory.
		$filename = wp_unique_filename( $uploads['path'], $filename );

		// Save to disk.
		$saved = $image_editor->save( $uploads['path'] . "/$filename" );

		if ( is_wp_error( $saved ) ) {
			return $saved;
		}

		// Create new attachment post.
		$new_attachment_post = array(
			'post_mime_type' => $saved['mime-type'],
			'guid'           => $uploads['url'] . "/$filename",
			'post_title'     => $image_name,
			'post_content'   => '',
		);

		// Copy post_content, post_excerpt, and post_title from the edited image's attachment post.
		$attachment_post = get_post( $attachment_id );

		if ( $attachment_post ) {
			$new_attachment_post['post_content'] = $attachment_post->post_content;
			$new_attachment_post['post_excerpt'] = $attachment_post->post_excerpt;
			$new_attachment_post['post_title']   = $attachment_post->post_title;
		}

		$new_attachment_id = wp_insert_attachment( wp_slash( $new_attachment_post ), $saved['path'], 0, true );

		if ( is_wp_error( $new_attachment_id ) ) {
			if ( 'db_update_error' === $new_attachment_id->get_error_code() ) {
				$new_attachment_id->add_data( array( 'status' => 500 ) );
			} else {
				$new_attachment_id->add_data( array( 'status' => 400 ) );
			}

			return $new_attachment_id;
		}

		// Copy the image alt text from the edited image.
		$image_alt = get_post_meta( $attachment_id, '_wp_attachment_image_alt', true );

		if ( ! empty( $image_alt ) ) {
			// update_post_meta() expects slashed.
			update_post_meta( $new_attachment_id, '_wp_attachment_image_alt', wp_slash( $image_alt ) );
		}

		if ( defined( 'REST_REQUEST' ) && REST_REQUEST ) {
			/*
			 * Set a custom header with the attachment_id.
			 * Used by the browser/client to resume creating image sub-sizes after a PHP fatal error.
			 */
			header( 'X-WP-Upload-Attachment-ID: ' . $new_attachment_id );
		}

		// Generate image sub-sizes and meta.
		$new_image_meta = wp_generate_attachment_metadata( $new_attachment_id, $saved['path'] );

		// Copy the EXIF metadata from the original attachment if not generated for the edited image.
		if ( isset( $image_meta['image_meta'] ) && isset( $new_image_meta['image_meta'] ) && is_array( $new_image_meta['image_meta'] ) ) {
			// Merge but skip empty values.
			foreach ( (array) $image_meta['image_meta'] as $key => $value ) {
				if ( empty( $new_image_meta['image_meta'][ $key ] ) && ! empty( $value ) ) {
					$new_image_meta['image_meta'][ $key ] = $value;
				}
			}
		}

		// Reset orientation. At this point the image is edited and orientation is correct.
		if ( ! empty( $new_image_meta['image_meta']['orientation'] ) ) {
			$new_image_meta['image_meta']['orientation'] = 1;
		}

		// The attachment_id may change if the site is exported and imported.
		$new_image_meta['parent_image'] = array(
			'attachment_id' => $attachment_id,
			// Path to the originally uploaded image file relative to the uploads directory.
			'file'          => _wp_relative_upload_path( $image_file ),
		);

		/**
		 * Filters the meta data for the new image created by editing an existing image.
		 *
		 * @since 5.5.0
		 *
		 * @param array $new_image_meta    Meta data for the new image.
		 * @param int   $new_attachment_id Attachment post ID for the new image.
		 * @param int   $attachment_id     Attachment post ID for the edited (parent) image.
		 */
		$new_image_meta = apply_filters( 'wp_edited_image_metadata', $new_image_meta, $new_attachment_id, $attachment_id );

		wp_update_attachment_metadata( $new_attachment_id, $new_image_meta );

		$response = $this->prepare_item_for_response( get_post( $new_attachment_id ), $request );
		$response->set_status( 201 );
		$response->header( 'Location', rest_url( sprintf( '%s/%s/%s', $this->namespace, $this->rest_base, $new_attachment_id ) ) );

		return $response;
	}

	/**
	 * Prepares a single attachment for create or update.
	 *
	 * @since 4.7.0
	 *
	 * @param WP_REST_Request $request Request object.
	 * @return stdClass|WP_Error Post object.
	 */
	protected function prepare_item_for_database( $request ) {
		$prepared_attachment = parent::prepare_item_for_database( $request );

		// Attachment caption (post_excerpt internally).
		if ( isset( $request['caption'] ) ) {
			if ( is_string( $request['caption'] ) ) {
				$prepared_attachment->post_excerpt = $request['caption'];
			} elseif ( isset( $request['caption']['raw'] ) ) {
				$prepared_attachment->post_excerpt = $request['caption']['raw'];
			}
		}

		// Attachment description (post_content internally).
		if ( isset( $request['description'] ) ) {
			if ( is_string( $request['description'] ) ) {
				$prepared_attachment->post_content = $request['description'];
			} elseif ( isset( $request['description']['raw'] ) ) {
				$prepared_attachment->post_content = $request['description']['raw'];
			}
		}

		if ( isset( $request['post'] ) ) {
			$prepared_attachment->post_parent = (int) $request['post'];
		}

		return $prepared_attachment;
	}

	/**
	 * Prepares a single attachment output for response.
	 *
	 * @since 4.7.0
	 * @since 5.9.0 Renamed `$post` to `$item` to match parent class for PHP 8 named parameter support.
	 *
	 * @param WP_Post         $item    Attachment object.
	 * @param WP_REST_Request $request Request object.
	 * @return WP_REST_Response Response object.
	 */
	public function prepare_item_for_response( $item, $request ) {
		// Restores the more descriptive, specific name for use within this method.
		$post     = $item;
		$response = parent::prepare_item_for_response( $post, $request );
		$fields   = $this->get_fields_for_response( $request );
		$data     = $response->get_data();

		if ( in_array( 'description', $fields, true ) ) {
			$data['description'] = array(
				'raw'      => $post->post_content,
				/** This filter is documented in wp-includes/post-template.php */
				'rendered' => apply_filters( 'the_content', $post->post_content ),
			);
		}

		if ( in_array( 'caption', $fields, true ) ) {
			/** This filter is documented in wp-includes/post-template.php */
			$caption = apply_filters( 'get_the_excerpt', $post->post_excerpt, $post );

			/** This filter is documented in wp-includes/post-template.php */
			$caption = apply_filters( 'the_excerpt', $caption );

			$data['caption'] = array(
				'raw'      => $post->post_excerpt,
				'rendered' => $caption,
			);
		}

		if ( in_array( 'alt_text', $fields, true ) ) {
			$data['alt_text'] = get_post_meta( $post->ID, '_wp_attachment_image_alt', true );
		}

		if ( in_array( 'media_type', $fields, true ) ) {
			$data['media_type'] = wp_attachment_is_image( $post->ID ) ? 'image' : 'file';
		}

		if ( in_array( 'mime_type', $fields, true ) ) {
			$data['mime_type'] = $post->post_mime_type;
		}

		if ( in_array( 'media_details', $fields, true ) ) {
			$data['media_details'] = wp_get_attachment_metadata( $post->ID );

			// Ensure empty details is an empty object.
			if ( empty( $data['media_details'] ) ) {
				$data['media_details'] = new stdClass();
			} elseif ( ! empty( $data['media_details']['sizes'] ) ) {

				foreach ( $data['media_details']['sizes'] as $size => &$size_data ) {

					if ( isset( $size_data['mime-type'] ) ) {
						$size_data['mime_type'] = $size_data['mime-type'];
						unset( $size_data['mime-type'] );
					}

					// Use the same method image_downsize() does.
					$image_src = wp_get_attachment_image_src( $post->ID, $size );
					if ( ! $image_src ) {
						continue;
					}

					$size_data['source_url'] = $image_src[0];
				}

				$full_src = wp_get_attachment_image_src( $post->ID, 'full' );

				if ( ! empty( $full_src ) ) {
					$data['media_details']['sizes']['full'] = array(
						'file'       => wp_basename( $full_src[0] ),
						'width'      => $full_src[1],
						'height'     => $full_src[2],
						'mime_type'  => $post->post_mime_type,
						'source_url' => $full_src[0],
					);
				}
			} else {
				$data['media_details']['sizes'] = new stdClass();
			}
		}

		if ( in_array( 'post', $fields, true ) ) {
			$data['post'] = ! empty( $post->post_parent ) ? (int) $post->post_parent : null;
		}

		if ( in_array( 'source_url', $fields, true ) ) {
			$data['source_url'] = wp_get_attachment_url( $post->ID );
		}

		if ( in_array( 'missing_image_sizes', $fields, true ) ) {
			require_once ABSPATH . 'wp-admin/includes/image.php';
			$data['missing_image_sizes'] = array_keys( wp_get_missing_image_subsizes( $post->ID ) );
		}

		$context = ! empty( $request['context'] ) ? $request['context'] : 'view';

		$data = $this->filter_response_by_context( $data, $context );

		$links = $response->get_links();

		// Wrap the data in a response object.
		$response = rest_ensure_response( $data );

		foreach ( $links as $rel => $rel_links ) {
			foreach ( $rel_links as $link ) {
				$response->add_link( $rel, $link['href'], $link['attributes'] );
			}
		}

		/**
		 * Filters an attachment returned from the REST API.
		 *
		 * Allows modification of the attachment right before it is returned.
		 *
		 * @since 4.7.0
		 *
		 * @param WP_REST_Response $response The response object.
		 * @param WP_Post          $post     The original attachment post.
		 * @param WP_REST_Request  $request  Request used to generate the response.
		 */
		return apply_filters( 'rest_prepare_attachment', $response, $post, $request );
	}

	/**
	 * Retrieves the attachment's schema, conforming to JSON Schema.
	 *
	 * @since 4.7.0
	 *
	 * @return array Item schema as an array.
	 */
	public function get_item_schema() {
		if ( $this->schema ) {
			return $this->add_additional_fields_schema( $this->schema );
		}

		$schema = parent::get_item_schema();

		$schema['properties']['alt_text'] = array(
			'description' => __( 'Alternative text to display when attachment is not displayed.' ),
			'type'        => 'string',
			'context'     => array( 'view', 'edit', 'embed' ),
			'arg_options' => array(
				'sanitize_callback' => 'sanitize_text_field',
			),
		);

		$schema['properties']['caption'] = array(
			'description' => __( 'The attachment caption.' ),
			'type'        => 'object',
			'context'     => array( 'view', 'edit', 'embed' ),
			'arg_options' => array(
				'sanitize_callback' => null, // Note: sanitization implemented in self::prepare_item_for_database().
				'validate_callback' => null, // Note: validation implemented in self::prepare_item_for_database().
			),
			'properties'  => array(
				'raw'      => array(
					'description' => __( 'Caption for the attachment, as it exists in the database.' ),
					'type'        => 'string',
					'context'     => array( 'edit' ),
				),
				'rendered' => array(
					'description' => __( 'HTML caption for the attachment, transformed for display.' ),
					'type'        => 'string',
					'context'     => array( 'view', 'edit', 'embed' ),
					'readonly'    => true,
				),
			),
		);

		$schema['properties']['description'] = array(
			'description' => __( 'The attachment description.' ),
			'type'        => 'object',
			'context'     => array( 'view', 'edit' ),
			'arg_options' => array(
				'sanitize_callback' => null, // Note: sanitization implemented in self::prepare_item_for_database().
				'validate_callback' => null, // Note: validation implemented in self::prepare_item_for_database().
			),
			'properties'  => array(
				'raw'      => array(
					'description' => __( 'Description for the attachment, as it exists in the database.' ),
					'type'        => 'string',
					'context'     => array( 'edit' ),
				),
				'rendered' => array(
					'description' => __( 'HTML description for the attachment, transformed for display.' ),
					'type'        => 'string',
					'context'     => array( 'view', 'edit' ),
					'readonly'    => true,
				),
			),
		);

		$schema['properties']['media_type'] = array(
			'description' => __( 'Attachment type.' ),
			'type'        => 'string',
			'enum'        => array( 'image', 'file' ),
			'context'     => array( 'view', 'edit', 'embed' ),
			'readonly'    => true,
		);

		$schema['properties']['mime_type'] = array(
			'description' => __( 'The attachment MIME type.' ),
			'type'        => 'string',
			'context'     => array( 'view', 'edit', 'embed' ),
			'readonly'    => true,
		);

		$schema['properties']['media_details'] = array(
			'description' => __( 'Details about the media file, specific to its type.' ),
			'type'        => 'object',
			'context'     => array( 'view', 'edit', 'embed' ),
			'readonly'    => true,
		);

		$schema['properties']['post'] = array(
			'description' => __( 'The ID for the associated post of the attachment.' ),
			'type'        => 'integer',
			'context'     => array( 'view', 'edit' ),
		);

		$schema['properties']['source_url'] = array(
			'description' => __( 'URL to the original attachment file.' ),
			'type'        => 'string',
			'format'      => 'uri',
			'context'     => array( 'view', 'edit', 'embed' ),
			'readonly'    => true,
		);

		$schema['properties']['missing_image_sizes'] = array(
			'description' => __( 'List of the missing image sizes of the attachment.' ),
			'type'        => 'array',
			'items'       => array( 'type' => 'string' ),
			'context'     => array( 'edit' ),
			'readonly'    => true,
		);

		unset( $schema['properties']['password'] );

		$this->schema = $schema;

		return $this->add_additional_fields_schema( $this->schema );
	}

	/**
	 * Handles an upload via raw POST data.
	 *
	 * @since 4.7.0
	 *
	 * @param string $data    Supplied file data.
	 * @param array  $headers HTTP headers from the request.
	 * @return array|WP_Error Data from wp_handle_sideload().
	 */
	protected function upload_from_data( $data, $headers ) {
		if ( empty( $data ) ) {
			return new WP_Error(
				'rest_upload_no_data',
				__( 'No data supplied.' ),
				array( 'status' => 400 )
			);
		}

		if ( empty( $headers['content_type'] ) ) {
			return new WP_Error(
				'rest_upload_no_content_type',
				__( 'No Content-Type supplied.' ),
				array( 'status' => 400 )
			);
		}

		if ( empty( $headers['content_disposition'] ) ) {
			return new WP_Error(
				'rest_upload_no_content_disposition',
				__( 'No Content-Disposition supplied.' ),
				array( 'status' => 400 )
			);
		}

		$filename = self::get_filename_from_disposition( $headers['content_disposition'] );

		if ( empty( $filename ) ) {
			return new WP_Error(
				'rest_upload_invalid_disposition',
				__( 'Invalid Content-Disposition supplied. Content-Disposition needs to be formatted as `attachment; filename="image.png"` or similar.' ),
				array( 'status' => 400 )
			);
		}

		if ( ! empty( $headers['content_md5'] ) ) {
			$content_md5 = array_shift( $headers['content_md5'] );
			$expected    = trim( $content_md5 );
			$actual      = md5( $data );

			if ( $expected !== $actual ) {
				return new WP_Error(
					'rest_upload_hash_mismatch',
					__( 'Content hash did not match expected.' ),
					array( 'status' => 412 )
				);
			}
		}

		// Get the content-type.
		$type = array_shift( $headers['content_type'] );

		// Include filesystem functions to get access to wp_tempnam() and wp_handle_sideload().
		require_once ABSPATH . 'wp-admin/includes/file.php';

		// Save the file.
		$tmpfname = wp_tempnam( $filename );

		$fp = fopen( $tmpfname, 'w+' );

		if ( ! $fp ) {
			return new WP_Error(
				'rest_upload_file_error',
				__( 'Could not open file handle.' ),
				array( 'status' => 500 )
			);
		}

		fwrite( $fp, $data );
		fclose( $fp );

		// Now, sideload it in.
		$file_data = array(
			'error'    => null,
			'tmp_name' => $tmpfname,
			'name'     => $filename,
			'type'     => $type,
		);

		$size_check = self::check_upload_size( $file_data );
		if ( is_wp_error( $size_check ) ) {
			return $size_check;
		}

		$overrides = array(
			'test_form' => false,
		);

		$sideloaded = wp_handle_sideload( $file_data, $overrides );

		if ( isset( $sideloaded['error'] ) ) {
			@unlink( $tmpfname );

			return new WP_Error(
				'rest_upload_sideload_error',
				$sideloaded['error'],
				array( 'status' => 500 )
			);
		}

		return $sideloaded;
	}

	/**
	 * Parses filename from a Content-Disposition header value.
	 *
	 * As per RFC6266:
	 *
	 *     content-disposition = "Content-Disposition" ":"
	 *                            disposition-type *( ";" disposition-parm )
	 *
	 *     disposition-type    = "inline" | "attachment" | disp-ext-type
	 *                         ; case-insensitive
	 *     disp-ext-type       = token
	 *
	 *     disposition-parm    = filename-parm | disp-ext-parm
	 *
	 *     filename-parm       = "filename" "=" value
	 *                         | "filename*" "=" ext-value
	 *
	 *     disp-ext-parm       = token "=" value
	 *                         | ext-token "=" ext-value
	 *     ext-token           = <the characters in token, followed by "*">
	 *
	 * @since 4.7.0
	 *
	 * @link https://tools.ietf.org/html/rfc2388
	 * @link https://tools.ietf.org/html/rfc6266
	 *
	 * @param string[] $disposition_header List of Content-Disposition header values.
	 * @return string|null Filename if available, or null if not found.
	 */
	public static function get_filename_from_disposition( $disposition_header ) {
		// Get the filename.
		$filename = null;

		foreach ( $disposition_header as $value ) {
			$value = trim( $value );

			if ( ! str_contains( $value, ';' ) ) {
				continue;
			}

			list( $type, $attr_parts ) = explode( ';', $value, 2 );

			$attr_parts = explode( ';', $attr_parts );
			$attributes = array();

			foreach ( $attr_parts as $part ) {
				if ( ! str_contains( $part, '=' ) ) {
					continue;
				}

				list( $key, $value ) = explode( '=', $part, 2 );

				$attributes[ trim( $key ) ] = trim( $value );
			}

			if ( empty( $attributes['filename'] ) ) {
				continue;
			}

			$filename = trim( $attributes['filename'] );

			// Unquote quoted filename, but after trimming.
			if ( str_starts_with( $filename, '"' ) && str_ends_with( $filename, '"' ) ) {
				$filename = substr( $filename, 1, -1 );
			}
		}

		return $filename;
	}

	/**
	 * Retrieves the query params for collections of attachments.
	 *
	 * @since 4.7.0
	 *
	 * @return array Query parameters for the attachment collection as an array.
	 */
	public function get_collection_params() {
		$params                            = parent::get_collection_params();
		$params['status']['default']       = 'inherit';
		$params['status']['items']['enum'] = array( 'inherit', 'private', 'trash' );
		$media_types                       = $this->get_media_types();

		$params['media_type'] = array(
			'default'     => null,
			'description' => __( 'Limit result set to attachments of a particular media type.' ),
			'type'        => 'string',
			'enum'        => array_keys( $media_types ),
		);

		$params['mime_type'] = array(
			'default'     => null,
			'description' => __( 'Limit result set to attachments of a particular MIME type.' ),
			'type'        => 'string',
		);

		return $params;
	}

	/**
	 * Handles an upload via multipart/form-data ($_FILES).
	 *
	 * @since 4.7.0
	 *
	 * @param array $files   Data from the `$_FILES` superglobal.
	 * @param array $headers HTTP headers from the request.
	 * @return array|WP_Error Data from wp_handle_upload().
	 */
	protected function upload_from_file( $files, $headers ) {
		if ( empty( $files ) ) {
			return new WP_Error(
				'rest_upload_no_data',
				__( 'No data supplied.' ),
				array( 'status' => 400 )
			);
		}

		// Verify hash, if given.
		if ( ! empty( $headers['content_md5'] ) ) {
			$content_md5 = array_shift( $headers['content_md5'] );
			$expected    = trim( $content_md5 );
			$actual      = md5_file( $files['file']['tmp_name'] );

			if ( $expected !== $actual ) {
				return new WP_Error(
					'rest_upload_hash_mismatch',
					__( 'Content hash did not match expected.' ),
					array( 'status' => 412 )
				);
			}
		}

		// Pass off to WP to handle the actual upload.
		$overrides = array(
			'test_form' => false,
		);

		// Bypasses is_uploaded_file() when running unit tests.
		if ( defined( 'DIR_TESTDATA' ) && DIR_TESTDATA ) {
			$overrides['action'] = 'wp_handle_mock_upload';
		}

		$size_check = self::check_upload_size( $files['file'] );
		if ( is_wp_error( $size_check ) ) {
			return $size_check;
		}

		// Include filesystem functions to get access to wp_handle_upload().
		require_once ABSPATH . 'wp-admin/includes/file.php';

		$file = wp_handle_upload( $files['file'], $overrides );

		if ( isset( $file['error'] ) ) {
			return new WP_Error(
				'rest_upload_unknown_error',
				$file['error'],
				array( 'status' => 500 )
			);
		}

		return $file;
	}

	/**
	 * Retrieves the supported media types.
	 *
	 * Media types are considered the MIME type category.
	 *
	 * @since 4.7.0
	 *
	 * @return array Array of supported media types.
	 */
	protected function get_media_types() {
		$media_types = array();

		foreach ( get_allowed_mime_types() as $mime_type ) {
			$parts = explode( '/', $mime_type );

			if ( ! isset( $media_types[ $parts[0] ] ) ) {
				$media_types[ $parts[0] ] = array();
			}

			$media_types[ $parts[0] ][] = $mime_type;
		}

		return $media_types;
	}

	/**
	 * Determine if uploaded file exceeds space quota on multisite.
	 *
	 * Replicates check_upload_size().
	 *
	 * @since 4.9.8
	 *
	 * @param array $file $_FILES array for a given file.
	 * @return true|WP_Error True if can upload, error for errors.
	 */
	protected function check_upload_size( $file ) {
		if ( ! is_multisite() ) {
			return true;
		}

		if ( get_site_option( 'upload_space_check_disabled' ) ) {
			return true;
		}

		$space_left = get_upload_space_available();

		$file_size = filesize( $file['tmp_name'] );

		if ( $space_left < $file_size ) {
			return new WP_Error(
				'rest_upload_limited_space',
				/* translators: %s: Required disk space in kilobytes. */
				sprintf( __( 'Not enough space to upload. %s KB needed.' ), number_format( ( $file_size - $space_left ) / KB_IN_BYTES ) ),
				array( 'status' => 400 )
			);
		}

		if ( $file_size > ( KB_IN_BYTES * get_site_option( 'fileupload_maxk', 1500 ) ) ) {
			return new WP_Error(
				'rest_upload_file_too_big',
				/* translators: %s: Maximum allowed file size in kilobytes. */
				sprintf( __( 'This file is too big. Files must be less than %s KB in size.' ), get_site_option( 'fileupload_maxk', 1500 ) ),
				array( 'status' => 400 )
			);
		}

		// Include multisite admin functions to get access to upload_is_user_over_quota().
		require_once ABSPATH . 'wp-admin/includes/ms.php';

		if ( upload_is_user_over_quota( false ) ) {
			return new WP_Error(
				'rest_upload_user_quota_exceeded',
				__( 'You have used your space quota. Please delete files before uploading.' ),
				array( 'status' => 400 )
			);
		}

		return true;
	}

	/**
	 * Gets the request args for the edit item route.
	 *
	 * @since 5.5.0
	 *
	 * @return array
	 */
	protected function get_edit_media_item_args() {
		return array(
			'src'       => array(
				'description' => __( 'URL to the edited image file.' ),
				'type'        => 'string',
				'format'      => 'uri',
				'required'    => true,
			),
			'modifiers' => array(
				'description' => __( 'Array of image edits.' ),
				'type'        => 'array',
				'minItems'    => 1,
				'items'       => array(
					'description' => __( 'Image edit.' ),
					'type'        => 'object',
					'required'    => array(
						'type',
						'args',
					),
					'oneOf'       => array(
						array(
							'title'      => __( 'Rotation' ),
							'properties' => array(
								'type' => array(
									'description' => __( 'Rotation type.' ),
									'type'        => 'string',
									'enum'        => array( 'rotate' ),
								),
								'args' => array(
									'description' => __( 'Rotation arguments.' ),
									'type'        => 'object',
									'required'    => array(
										'angle',
									),
									'properties'  => array(
										'angle' => array(
											'description' => __( 'Angle to rotate clockwise in degrees.' ),
											'type'        => 'number',
										),
									),
								),
							),
						),
						array(
							'title'      => __( 'Crop' ),
							'properties' => array(
								'type' => array(
									'description' => __( 'Crop type.' ),
									'type'        => 'string',
									'enum'        => array( 'crop' ),
								),
								'args' => array(
									'description' => __( 'Crop arguments.' ),
									'type'        => 'object',
									'required'    => array(
										'left',
										'top',
										'width',
										'height',
									),
									'properties'  => array(
										'left'   => array(
											'description' => __( 'Horizontal position from the left to begin the crop as a percentage of the image width.' ),
											'type'        => 'number',
										),
										'top'    => array(
											'description' => __( 'Vertical position from the top to begin the crop as a percentage of the image height.' ),
											'type'        => 'number',
										),
										'width'  => array(
											'description' => __( 'Width of the crop as a percentage of the image width.' ),
											'type'        => 'number',
										),
										'height' => array(
											'description' => __( 'Height of the crop as a percentage of the image height.' ),
											'type'        => 'number',
										),
									),
								),
							),
						),
					),
				),
			),
			'rotation'  => array(
				'description'      => __( 'The amount to rotate the image clockwise in degrees. DEPRECATED: Use `modifiers` instead.' ),
				'type'             => 'integer',
				'minimum'          => 0,
				'exclusiveMinimum' => true,
				'maximum'          => 360,
				'exclusiveMaximum' => true,
			),
			'x'         => array(
				'description' => __( 'As a percentage of the image, the x position to start the crop from. DEPRECATED: Use `modifiers` instead.' ),
				'type'        => 'number',
				'minimum'     => 0,
				'maximum'     => 100,
			),
			'y'         => array(
				'description' => __( 'As a percentage of the image, the y position to start the crop from. DEPRECATED: Use `modifiers` instead.' ),
				'type'        => 'number',
				'minimum'     => 0,
				'maximum'     => 100,
			),
			'width'     => array(
				'description' => __( 'As a percentage of the image, the width to crop the image to. DEPRECATED: Use `modifiers` instead.' ),
				'type'        => 'number',
				'minimum'     => 0,
				'maximum'     => 100,
			),
			'height'    => array(
				'description' => __( 'As a percentage of the image, the height to crop the image to. DEPRECATED: Use `modifiers` instead.' ),
				'type'        => 'number',
				'minimum'     => 0,
				'maximum'     => 100,
			),
		);
	}

}