<?php
/**
 * Utilities.
 *
 * @package automattic/jetpack-publicize
 */

namespace Automattic\Jetpack\Publicize\Social_Image_Generator;

use Automattic\Jetpack\Publicize\Publicize_Utils as Utils;
use Automattic\Jetpack\Publicize\REST_API\Proxy_Requests;
use Automattic\Jetpack\Redirect;
use WP_Error;
use WP_REST_Request;

/**
 * Given a post ID, returns the image URL for the generated image.
 *
 * @param int $post_id Post ID to get the URL for.
 * @return string
 */
function get_image_url( $post_id ) {
	$post_settings = new Post_Settings( $post_id );
	$token         = $post_settings->get_token();

	if ( ! $post_settings->is_enabled() || empty( $token ) ) {
		return '';
	}

	return add_query_arg(
		array( 'query' => rawurlencode( 't=' . $token ) ),
		Redirect::get_url( 'sigenerate', array( 'site' => null ) )
	);
}

/**
 * Get the parameters for the token body.
 *
 * @param string $text Text to use in the generated image.
 * @param string $image_url Image to use in the generated image.
 * @param string $template Template to use in the generated image.
 * @param string $font Font to use in the generated image.
 * @return array
 */
function get_token_body( $text, $image_url, $template, $font = '' ) {
	return array(
		'text'      => $text,
		'image_url' => $image_url,
		'template'  => $template,
		'font'      => $font,
	);
}

/**
 * Fetch a token from the WPCOM endpoint.
 *
 * @param string $text      The text that will be displayed on the generated image.
 * @param string $image_url The background image URL to be used in the generated image.
 * @param string $template  The template slug to use for generating the image.
 * @param string $font The font slug to use for the text in the image.
 * @return string|WP_Error  The generated token or a WP_Error object if there's been a problem.
 */
function fetch_token( $text, $image_url, $template, $font = '' ) {

	$args = get_token_body( $text, $image_url, $template, $font );

	if ( Utils::is_wpcom() ) {
		require_lib( 'social-image-generator-token' );
		require_lib( 'publicize/util/social-image-generator' );

		if ( ! \Publicize\Social_Image_Generator\is_enabled() ) {
			return new WP_Error( 'social_image_generator_not_enabled', __( 'Social Image Generator is not enabled.', 'jetpack-publicize-pkg' ) );
		}

		return \Social_Image_Generator\generate_token( $args );
	}

	$proxy = new Proxy_Requests( 'publicize/social-image-generator' );

	$request = new WP_REST_Request( 'POST' );

	$request->set_body( wp_json_encode( $args ) );

	return $proxy->proxy_request_to_wpcom_as_blog( $request, 'generate-token' );
}
