<?php

namespace WP_CLI\Context;

use WP_CLI;
use WP_CLI\Context;
use WP_Session_Tokens;

/**
 * Context which simulates the administrator backend.
 */
final class Admin implements Context {

    /**
     * Process the context to set up the environment correctly.
     *
     * @param array $config Associative array of configuration data.
     * @return void
     */
    public function process( $config ) {
        if ( defined( 'WP_ADMIN' ) ) {
            if ( ! WP_ADMIN ) {
                WP_CLI::warning( 'Could not fake admin request.' );
            }

            return;
        }

        WP_CLI::debug( 'Faking an admin request', Context::DEBUG_GROUP );

        // Define `WP_ADMIN` as being true. This causes the helper method
        // `is_admin()` to return true as well.
        define( 'WP_ADMIN', true ); // phpcs:ignore WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedConstantFound

        // Set a fake entry point to ensure wp-includes/vars.php does not throw
        // notices/errors. This will be reflected in the global `$pagenow`
        // variable being set to 'wp-cli-fake-admin-file.php'.
        $_SERVER['PHP_SELF'] = '/wp-admin/wp-cli-fake-admin-file.php';

        // Bootstrap the WordPress administration area.
        WP_CLI::add_wp_hook(
            'init',
            function () {
                $this->log_in_as_admin_user();
                $this->load_admin_environment();
            },
            defined( 'PHP_INT_MIN' ) ? PHP_INT_MIN : -2147483648, // phpcs:ignore PHPCompatibility.Constants.NewConstants.php_int_minFound
            0
        );
    }

    /**
     * Ensure the current request is done under a logged-in administrator
     * account.
     *
     * A lot of premium plugins/themes have their custom update routines locked
     * behind an is_admin() call.
     *
     * @return void
     */
    private function log_in_as_admin_user() {
        // TODO: Add logic to find an administrator user.
        $admin_user_id = 1;

        wp_set_current_user( $admin_user_id );

        $expiration = time() + DAY_IN_SECONDS;

        $_COOKIE[ AUTH_COOKIE ] = wp_generate_auth_cookie(
            $admin_user_id,
            $expiration,
            'auth'
        );

        $_COOKIE[ SECURE_AUTH_COOKIE ] = wp_generate_auth_cookie(
            $admin_user_id,
            $expiration,
            'secure_auth'
        );
    }

    /**
     * Load the admin environment.
     *
     * This tries to load `wp-admin/admin.php` while trying to avoid issues
     * like re-loading the wp-config.php file (which redeclares constants).
     *
     * To make this work across WordPress versions, we use the actual file and
     * modify it on-the-fly.
     *
     * @global string $hook_suffix
     * @global string $pagenow
     * @global int    $wp_db_version
     * @global array  $_wp_submenu_nopriv
     *
     * @return void
     */
    private function load_admin_environment() {
        global $hook_suffix, $pagenow, $wp_db_version, $_wp_submenu_nopriv;

        if ( ! isset( $hook_suffix ) ) {
            $hook_suffix = 'index'; // phpcs:ignore WordPress.WP.GlobalVariablesOverride.Prohibited
        }

        // Make sure we don't trigger a DB upgrade as that tries to redirect
        // the page.
        $wp_db_version = (int) get_option( 'db_version' ); // phpcs:ignore WordPress.WP.GlobalVariablesOverride.Prohibited

        // Ensure WP does not iterate over an undefined variable in
        // `user_can_access_admin_page()`.
        if ( ! isset( $_wp_submenu_nopriv ) ) {
            $_wp_submenu_nopriv = []; // phpcs:ignore WordPress.WP.GlobalVariablesOverride.Prohibited
        }

        $admin_php_file = file_get_contents( ABSPATH . 'wp-admin/admin.php' );

        // First we remove the opening and closing PHP tags.
        $admin_php_file = preg_replace( '/^<\?php\s+/', '', $admin_php_file );
        $admin_php_file = preg_replace( '/\s+\?>$/', '', $admin_php_file );

        // Then we remove the loading of either wp-config.php or wp-load.php.
        $admin_php_file = preg_replace( '/^\s*(?:include|require).*[\'"]\/?wp-(?:load|config)\.php[\'"]\s*\)?;\s*$/m', '', $admin_php_file );

        // We also remove the authentication redirect.
        $admin_php_file = preg_replace( '/^\s*auth_redirect\(\);$/m', '', $admin_php_file );

        // Finally, we avoid sending headers.
        $admin_php_file   = preg_replace( '/^\s*nocache_headers\(\);$/m', '', $admin_php_file );
        $_GET['noheader'] = true;

        eval( $admin_php_file ); // phpcs:ignore Squiz.PHP.Eval.Discouraged
    }
}