<?php
/**
 * Print the newest published beta/RC of a wordpress.org plugin, or nothing.
 *
 * Usage: SLUG=woocommerce php ci/latest-prerelease.php
 *
 * The .org API lists every published version, prereleases included. The newest
 * one that is not a plain stable release is what a shop on the beta channel
 * would get, which makes it the earliest available warning that the next
 * release breaks us. A prerelease *older* than current stable is a leftover
 * from a finished cycle and is ignored — testing it would answer a question
 * nobody asked.
 *
 * @package ci
 */

$slug = getenv( 'SLUG' );
if ( ! $slug ) {
	fwrite( STDERR, "SLUG is not set.\n" );
	exit( 1 );
}

$url = 'https://api.wordpress.org/plugins/info/1.2/?action=plugin_information'
	. '&request[slug]=' . rawurlencode( $slug )
	. '&request[fields][versions]=1';

$body = @file_get_contents( $url ); // phpcs:ignore WordPress.PHP.NoSilencedErrors
if ( false === $body ) {
	// A network blip must not fail the build — the caller falls back to the
	// stable release, which is still a useful test.
	fwrite( STDERR, "Could not reach the wordpress.org plugin API.\n" );
	exit( 0 );
}

$info  = json_decode( $body, true );
$stable = isset( $info['version'] ) ? $info['version'] : '0';

$pre = array_filter(
	array_keys( isset( $info['versions'] ) ? $info['versions'] : array() ),
	static function ( $version ) {
		return (bool) preg_match( '/-(beta|rc)/i', $version );
	}
);

usort( $pre, 'version_compare' );
$newest = end( $pre );

if ( $newest && version_compare( $newest, $stable, '>' ) ) {
	echo $newest;
}