<?php
/**
 * Image class.
 *
 * @package WPZinc\Social
 * @author WP Zinc
 */

namespace WPZinc\Social;

/**
 * Determines optimal image sizes and aspect ratios for each
 * social networks, detects if such sizes are registered
 * in WordPress and (where possible) resizes and crops
 * images.
 *
 * @package WPZinc\Social
 * @author  WP Zinc
 * @version 4.6.6
 */
class Image {

	/**
	 * Holds the base class object.
	 *
	 * @since   4.6.6
	 *
	 * @var     object
	 */
	public $base;

	/**
	 * Constructor
	 *
	 * @since   4.6.6
	 *
	 * @param   object $base    Base Plugin Class.
	 */
	public function __construct( $base ) {

		// Store base class.
		$this->base = $base;

	}

	/**
	 * Helper method to retrieve Image Options
	 *
	 * @since   3.4.3
	 *
	 * @param   bool        $network    Network (false = defaults).
	 * @param   bool|string $post_type  Post Type.
	 * @return  array              Image Options
	 */
	public function get_status_image_options( $network = false, $post_type = false ) {

		// If a Post Type has been specified, get its featured_image label.
		$label = __( 'Feat. Image', 'wp-to-buffer' );
		if ( $post_type !== false && $post_type !== 'bulk' ) {
			$post_type_object = get_post_type_object( $post_type );
			$label            = $post_type_object->labels->featured_image;
		}

		// Build featured image options.
		$options = array(
			'featured_image' => array(
				'label'             => $label,
				'additional_images' => true,
				'text_to_image'     => false,
			),
		);

		/**
		 * Defines the available Featured Image select dropdown options on a status, depending
		 * on the Plugin and Social Network the status message is for.
		 *
		 * @since   3.4.3
		 *
		 * @param   array   $options    Featured Image Dropdown Options.
		 * @param   bool|string $network    Social Network.
		 * @param   string  $post_type  Post Type.
		 */
		$options = apply_filters( $this->base->plugin->filter_name . '_get_status_image_options', $options, $network, $post_type );

		// Return filtered results.
		return $options;

	}

	/**
	 * Returns the image for the given Attachment ID, based on the social media service
	 * the image will be used for.
	 *
	 * If the image isn't a compatible mime type, this function will attempt to convert the image
	 * from e.g. webp --> jpg.
	 *
	 * Checks that the image will meet the aspect ratio requirements for posting to Instagram,
	 * returning a valid image if the large size would fail.
	 *
	 * @since   4.6.6
	 *
	 * @param   int         $image_id             Image ID.
	 * @param   string      $source               Source Image ID was derived from (plugin, featured_image, post_content, text_to_image).
	 * @param   bool|string $service              Social Media Service the image is for. If not defined, just return the large version.
	 * @param   bool|string $status_post_type     Status format (for example, 'story' or 'post' for Instagram).
	 * @return  array|\WP_Error                    Image ID, Image URLs, Source
	 */
	public function get_image_sources( $image_id, $source, $service = false, $status_post_type = false ) { // phpcs:ignore Generic.CodeAnalysis.UnusedFunctionParameter.FoundAfterLastUsed

		// Load WordPress image libraries, if they are not currently loaded.
		if ( ! class_exists( 'WP_Image_Editor' ) ) {
			require_once ABSPATH . WPINC . '/class-wp-image-editor.php';
			require_once ABSPATH . WPINC . '/class-wp-image-editor-gd.php';
			require_once ABSPATH . WPINC . '/class-wp-image-editor-imagick.php';
		}

		$image_mime_type = get_post_mime_type( $image_id );

		// If the image is a webp, attempt to convert it to a JPEG and store in the Media Library
		// as webp isn't supported by all social media services.
		// Check that the image source is a supported format i.e. not a webp.
		switch ( $image_mime_type ) {
			/**
			 * Webp
			 */
			case 'image/webp':
				// Don't do anything if the service supports webp and the image isn't for Instagram.
				// If it is for Instagram, we want to convert to a JPEG as we might need to resize/crop
				// later in this function.
				if ( $this->base->supports( 'webp' ) && $service !== 'instagram' ) {
					break;
				}

				// Get image.
				$image_path_and_file = get_attached_file( $image_id );

				// Return the large image sources if we couldn't get the image path and file.
				if ( empty( $image_path_and_file ) || ! file_exists( $image_path_and_file ) ) {
					return $this->get_image_source_by_size( $image_id, $source, 'large' );
				}

				// Load webp image.
				$image = wp_get_image_editor( $image_path_and_file );

				// Bail if an error occured.
				if ( is_wp_error( $image ) ) {
					return $image;
				}

				// Save to temporary file on disk.
				$converted_image = $image->save( get_temp_dir() . 'wpzinc-social-' . $image_id . '-converted-' . bin2hex( random_bytes( 5 ) ) );

				// Bail if an error occured.
				if ( is_wp_error( $converted_image ) ) {
					return $converted_image;
				}

				// Upload to Media Library.
				$converted_image_id = $this->base->get_class( 'media_library' )->upload_local_image( $converted_image['path'] );

				// Bail if an error occured.
				if ( is_wp_error( $converted_image_id ) ) {
					return $converted_image_id;
				}

				// Assign image ID.
				$image_id = $converted_image_id;
				break;

			default:
				/**
				 * Defines the image ID to use as the image or additional image for the status message.
				 * If an image's mime type is not supported by the social media scheduling service, this
				 * filter can be used to convert the image to a supported type, store it in the Media Library
				 * and return the converted image ID.
				 *
				 * This is already performed for webp images.
				 *
				 * @since   4.6.8
				 *
				 * @param   int     $image_id           Image ID.
				 * @param   string  $source             Source Image ID was derived from (plugin, featured_image, post_content, text_to_image).
				 * @param   string  $service            Social Media Service the image is for. If not defined, just return the large version.
				 * @param   string  $image_mime_type    Image MIME Type.
				 */
				$image_id = apply_filters( $this->base->plugin->filter_name . '_image_get_images_sources_convert', $image_id, $source, $service, $image_mime_type );
				break;
		}

		return $this->get_image_source_by_size( $image_id, $source, 'large' );

	}

	/**
	 * Returns an array comprising of the image ID, image URL and alt text for the requested size, thumbnail size
	 * and the source of the image.
	 *
	 * @since   4.6.6
	 *
	 * @param   int    $image_id   Image ID.
	 * @param   string $source     Source Image ID was derived from (plugin, featured_image, post_content, text_to_image).
	 * @param   string $size       WordPress Registered Image Size to return the image as.
	 * @return  array               Image ID, Image URLs, Source
	 */
	private function get_image_source_by_size( $image_id, $source, $size ) {

		// Get image at requested size.
		$image = wp_get_attachment_image_src( $image_id, $size );

		// Get thumbnail version, which some APIs might use for a small preview.
		$thumbnail = wp_get_attachment_image_src( $image_id, 'thumbnail' );

		// Return URLs only.
		return array(
			'id'        => $image_id,
			'image'     => ( is_array( $image ) ? strtok( $image[0], '?' ) : false ), // Strip query parameters that might break some APIs.
			'thumbnail' => ( is_array( $thumbnail ) ? strtok( $thumbnail[0], '?' ) : false ), // Strip query parameters that might break some APIs.
			'alt_text'  => get_post_meta( $image_id, '_wp_attachment_image_alt', true ),
			'source'    => $source,
			'width'     => ( is_array( $image ) ? $image[1] : '' ),
			'height'    => ( is_array( $image ) ? $image[2] : '' ),
		);

	}

}