<?php

namespace WP_CLI\Core;

use Exception;
use WP_CLI;
use WP_CLI\Utils;
use WP_Error;
use Core_Upgrader as DefaultCoreUpgrader;
use WP_Filesystem_Base;

/**
 * A Core Upgrader class that caches the download, and uses cached if available.
 *
 * @package wp-cli
 */
class CoreUpgrader extends DefaultCoreUpgrader {

    /**
     * Whether to retry without certificate validation on TLS handshake failure.
     *
     * @var bool
     */
    private $insecure;

    /**
     * CoreUpgrader constructor.
     *
     * @param \WP_Upgrader_Skin|null $skin
     * @param bool                   $insecure
     */
    public function __construct( $skin = null, $insecure = false ) {
        $this->insecure = $insecure;
        parent::__construct( $skin );
    }

    /**
     * Caches the download, and uses cached if available.
     *
     * @access public
     *
     * @param string $package          The URI of the package. If this is the full path to an
     *                                 existing local file, it will be returned untouched.
     * @param bool   $check_signatures Whether to validate file signatures. Default false.
     * @param array  $hook_extra       Extra arguments to pass to the filter hooks. Default empty array.
     * @return string|WP_Error The full path to the downloaded package file, or a WP_Error object.
     */
    public function download_package( $package, $check_signatures = false, $hook_extra = [] ) {

        /**
         * Filter whether to return the package.
         *
         * @since 3.7.0
         * @since 5.5.0 Added the `$hook_extra` parameter.
         *
         * @param bool         $reply      Whether to bail without returning the package. Default is false.
         * @param string       $package    The package file name.
         * @param \WP_Upgrader $upgrader   The WP_Upgrader instance.
         * @param array        $hook_extra Extra arguments passed to hooked filters.
         */
        $reply = apply_filters(
            // phpcs:ignore WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedHooknameFound -- Override existing hook from Core.
            'upgrader_pre_download',
            false,
            $package,
            $this,
            $hook_extra
        );

        /**
         * @var false|string|\WP_Error $reply
         */

        if ( false !== $reply ) {
            return $reply;
        }

        // Check if package is a local or remote file. Bail if it's local.
        if ( ! preg_match( '!^(http|https|ftp)://!i', $package ) && file_exists( $package ) ) {
            return $package;
        }

        if ( empty( $package ) ) {
            return new WP_Error( 'no_package', $this->strings['no_package'] );
        }

        $filename  = pathinfo( $package, PATHINFO_FILENAME );
        $extension = pathinfo( $package, PATHINFO_EXTENSION );

        $temp = Utils\get_temp_dir() . uniqid( 'wp_' ) . ".{$extension}";
        register_shutdown_function(
            function () use ( $temp ) {
                if ( file_exists( $temp ) ) {
                    unlink( $temp );
                }
            }
        );

        $cache     = WP_CLI::get_cache();
        $update    = $GLOBALS['wpcli_core_update_obj'];
        $cache_key = "core/{$filename}-{$update->locale}.{$extension}";

        /**
         * @var false|string $cache_file
         */
        $cache_file = $cache->has( $cache_key );

        if ( $cache_file && false === stripos( $package, 'https://wordpress.org/nightly-builds/' )
            && false === stripos( $package, 'http://wordpress.org/nightly-builds/' ) ) {
            WP_CLI::log( "Using cached file '{$cache_file}'..." );
            copy( $cache_file, $temp );
            return $temp;
        }

        /*
         * Download to a temporary file because piping from cURL to tar is flaky
         * on MinGW (and probably in other environments too).
         */
        $headers = [ 'Accept' => 'application/json' ];
        $options = [
            'timeout'       => 600,  // 10 minutes ought to be enough for everybody.
            'filename'      => $temp,
            'halt_on_error' => false,
            'insecure'      => $this->insecure,
        ];

        $this->skin->feedback( 'downloading_package', $package );

        try {
            /** @var \WpOrg\Requests\Response $response */
            $response = Utils\http_request( 'GET', $package, null, $headers, $options );
        } catch ( Exception $e ) {
            return new WP_Error( 'download_failed', $e->getMessage() );
        }

        if ( ! is_null( $response ) && 200 !== (int) $response->status_code ) {
            return new WP_Error( 'download_failed', $this->strings['download_failed'] );
        }

        if ( false === stripos( $package, 'https://wordpress.org/nightly-builds/' ) ) {
            $cache->import( $cache_key, $temp );
        }

        return $temp;
    }

    /**
     * Upgrade WordPress core.
     *
     * @access public
     *
     * @global WP_Filesystem_Base $wp_filesystem Subclass
     * @global callable           $_wp_filesystem_direct_method
     *
     * @param object $current Response object for whether WordPress is current.
     * @param array  $args {
     *        Optional. Arguments for upgrading WordPress core. Default empty array.
     *
     *        @type bool $pre_check_md5    Whether to check the file checksums before
     *                                     attempting the upgrade. Default true.
     *        @type bool $attempt_rollback Whether to attempt to rollback the chances if
     *                                     there is a problem. Default false.
     *        @type bool $do_rollback      Whether to perform this "upgrade" as a rollback.
     *                                     Default false.
     * }
     * @return string|false|WP_Error New WordPress version on success, false or WP_Error on failure.
     */
    public function upgrade( $current, $args = [] ) {
        set_error_handler( [ __CLASS__, 'error_handler' ], E_USER_WARNING | E_USER_NOTICE );

        $result = parent::upgrade( $current, $args );

        restore_error_handler();

        return $result;
    }

    /**
     * Error handler to ignore failures on accessing SSL "https://api.wordpress.org/core/checksums/1.0/" in `get_core_checksums()` which seem to occur intermittently.
     */
    public static function error_handler( $errno, $errstr, $errfile, $errline, $errcontext = null ) {
        // If ignoring E_USER_WARNING | E_USER_NOTICE, default.
        if ( ! ( error_reporting() & $errno ) ) {
            return false;
        }
        // If not in "wp-admin/includes/update.php", default.
        $update_php = 'wp-admin/includes/update.php';
        if ( 0 !== substr_compare( $errfile, $update_php, -strlen( $update_php ) ) ) {
            return false;
        }
        // Else assume it's in `get_core_checksums()` and just ignore it.
        return true;
    }
}