<?php
/**
 * Core checksums of one WordPress version and locale (N§A1).
 *
 * - version         string  WordPress version the sums belong to.
 * - locale          string  Locale of the sums actually used.
 * - requestedLocale string  Site package locale ("wp local package" global or en_US). When it differs
 *                           from locale, the sums are an en_US fallback (SPEC Tranché 3) and the
 *                           files of Assumptions::LOCALE_DEPENDENT_FILES are not compared.
 * - sums            array<string,string> path relative to ABSPATH => lowercase md5.
 *
 * @package Timaub\AfterHackChecklist
 */

namespace Timaub\AfterHackChecklist\Domain;

final class CoreChecksums {
	/** @var string */
	public $version = '';
	/** @var string */
	public $locale = '';
	/** @var string */
	public $requestedLocale = '';
	/** @var array<string,string> */
	public $sums = array();

	/**
	 * Reads the decoded body of api.wordpress.org/core/checksums/1.0/ called WITH a locale.
	 * Returns null for {"checksums":false} and for any other shape (the nested
	 * per-version shape only comes back without a locale, N§A1).
	 *
	 * @param mixed  $decoded         json_decode( $body, true ).
	 * @param string $version         Version asked.
	 * @param string $locale          Locale asked in this call.
	 * @param string $requestedLocale Site locale (equal to $locale unless this is the en_US fallback).
	 */
	public static function fromApiResponse( $decoded, string $version, string $locale, string $requestedLocale = '' ) {
		if ( ! is_array( $decoded ) || ! isset( $decoded['checksums'] ) || ! is_array( $decoded['checksums'] ) ) {
			return null;
		}
		$sums = array();
		foreach ( $decoded['checksums'] as $path => $md5 ) {
			if ( ! is_string( $md5 ) ) {
				return null;
			}
			$sums[ (string) $path ] = strtolower( $md5 );
		}
		if ( ! $sums ) {
			return null;
		}
		$c                  = new self();
		$c->version         = $version;
		$c->locale          = $locale;
		$c->requestedLocale = '' === $requestedLocale ? $locale : $requestedLocale;
		$c->sums            = $sums;
		return $c;
	}

	public function isFallback(): bool {
		return $this->locale !== $this->requestedLocale;
	}

	public function toArray(): array {
		return array(
			'version'         => $this->version,
			'locale'          => $this->locale,
			'requestedLocale' => $this->requestedLocale,
			'sums'            => $this->sums,
		);
	}

	public static function fromArray( array $a ): self {
		$c                  = new self();
		$c->version         = (string) $a['version'];
		$c->locale          = (string) $a['locale'];
		$c->requestedLocale = isset( $a['requestedLocale'] ) ? (string) $a['requestedLocale'] : $c->locale;
		$c->sums            = (array) $a['sums'];
		return $c;
	}
}