<?php
/**
 * Helper functions for SpeedNest.
 *
 * @package SpeedNest
 */

if ( ! defined( 'ABSPATH' ) ) {
    exit;
}

/**
 * Get default settings.
 *
 * @return array
 */
function wpsco_get_default_settings() {
    return array(
        // General.
        'safe_mode'                  => true,
        'emergency_disable'          => false,
        'delete_data_on_uninstall'   => false,

        // Cache.
        'page_cache_enabled'         => true,
        'page_cache_ttl'             => 3600,
        'cache_warming_enabled'      => false,
        'cache_warming_concurrency'  => 2,
        'cache_exclusions'           => array(
            'urls'     => array(),
            'patterns' => array( '/cart/*', '/checkout/*', '/my-account/*', '/wp-admin/*', '/wp-login.php' ),
            'cookies'  => array( 'wordpress_logged_in_', 'woocommerce_cart_hash', 'woocommerce_items_in_cart' ),
            'query'    => array(),
        ),

        // CSS.
        'css_minify'                 => false,
        'css_combine'                => false,
        'css_critical'               => false,
        'css_async'                  => true,
        'css_remove_unused'          => false,
        'css_remove_unused_mode'     => 'safe',
        'css_exclusions'             => array(),

        // JavaScript.
        'js_minify'                  => false,
        'js_combine'                 => false,
        'js_defer'                   => true,
        'js_delay'                   => true,
        'js_delay_timeout'           => 3,
        'js_delay_trigger'           => 'interaction',
        'js_move_to_footer'          => false,
        'js_exclusions'              => array(
            'jquery',
            'jquery-core',
            'jquery-migrate',
        ),
        'js_auto_exclusions'         => array(
            'wc-checkout',
            'wc-cart',
            'wc-add-to-cart',
            'stripe',
            'razorpay',
            'paypal',
            'ppcp',
            'recaptcha',
            'google-recaptcha',
            'elementor-frontend',
        ),

        // HTML.
        'html_minify'                => true,

        // Images.
        'lazy_load_images'           => true,
        'lazy_load_iframes'          => true,
        'lazy_load_videos'           => true,
        'add_missing_dimensions'     => true,
        'image_compression'          => true,
        'image_quality'              => 82,
        'webp_conversion'            => true,
        'avif_conversion'            => false,
        'lcp_image_preload'          => true,
        'lcp_image_url'              => '',
        'image_exclusions'           => array(),

        // Fonts.
        'font_display_swap'          => true,
        'google_fonts_local'         => false,
        'preload_fonts'              => false,
        'preload_font_urls'          => array(),

        // WordPress.
        'disable_emojis'             => true,
        'disable_embeds'             => true,
        'disable_xmlrpc'             => false,
        'remove_wp_version'          => true,
        'remove_generator_meta'      => true,
        'disable_feeds'              => false,
        'disable_pingbacks'          => false,
        'remove_shortlinks'          => false,
        'remove_discovery_links'     => false,
        'heartbeat_frontend'         => 'default',
        'heartbeat_admin'            => 'default',
        'heartbeat_editor'           => 'default',

        // Third-party.
        'delay_analytics'            => true,
        'delay_gtm'                  => true,
        'delay_facebook_pixel'       => true,
        'delay_clarity'              => true,
        'lazy_load_youtube'          => true,
        'lazy_load_vimeo'            => true,
        'lazy_load_google_maps'      => true,

        // Cloudflare.
        'cloudflare_enabled'         => false,
        'cloudflare_api_token'       => '',
        'cloudflare_zone_id'         => '',
        'cloudflare_auto_purge'      => false,

        // CDN.
        'cdn_enabled'                => false,
        'cdn_url'                    => '',
        'cdn_purge_endpoint'         => '',
        'cdn_api_key'                => '',

        // Server.
        'browser_cache_htaccess'     => true,
        'compression_htaccess'       => true,

        // Diagnostics.
        'pagespeed_api_key'          => '',

        // Conflicts.
        'dismissed_conflicts'        => array(),
        'locked_features'            => array(),
    );
}

/**
 * Get plugin settings.
 *
 * @param string|null $key Optional key.
 * @param mixed       $default Default value.
 * @return mixed
 */
function wpsco_get_setting( $key = null, $default = null ) {
    $settings = get_option( 'wpsco_settings', wpsco_get_default_settings() );
    $defaults = wpsco_get_default_settings();
    $settings = wp_parse_args( $settings, $defaults );

    if ( null === $key ) {
        return $settings;
    }

    return isset( $settings[ $key ] ) ? $settings[ $key ] : $default;
}

/**
 * Update a plugin setting.
 *
 * @param string $key   Setting key.
 * @param mixed  $value Setting value.
 * @return bool
 */
function wpsco_update_setting( $key, $value ) {
    $settings         = wpsco_get_setting();
    $settings[ $key ] = $value;
    return update_option( 'wpsco_settings', $settings );
}

/**
 * Check if current user can manage the plugin.
 *
 * @return bool
 */
function wpsco_current_user_can() {
    return current_user_can( WPSCO_CAPABILITY ) || current_user_can( 'manage_options' );
}

/**
 * Get plugin cache directory inside wp_upload_dir(), dynamically resolved at runtime.
 *
 * @param string $sub Optional subdirectory or relative file path.
 * @return string Normalized absolute path.
 */
function wpsco_get_cache_dir( $sub = '' ) {
    $upload_dir = wp_upload_dir();
    $basedir    = ! empty( $upload_dir['basedir'] ) ? $upload_dir['basedir'] : WP_CONTENT_DIR . '/uploads';
    $base       = wp_normalize_path( trailingslashit( $basedir ) . 'speednest/' );
    return $sub ? $base . ltrim( $sub, '/' ) : $base;
}

/**
 * Get plugin cache directory URL inside wp_upload_dir(), dynamically resolved at runtime.
 *
 * @param string $sub Optional subdirectory or relative file path.
 * @return string Cache URL.
 */
function wpsco_get_cache_url( $sub = '' ) {
    $upload_dir = wp_upload_dir();
    $baseurl    = ! empty( $upload_dir['baseurl'] ) ? $upload_dir['baseurl'] : content_url( 'uploads' );
    $base       = trailingslashit( $baseurl ) . 'speednest/';
    return $sub ? $base . ltrim( $sub, '/' ) : $base;
}

/**
 * Safely write content to a file in the uploads cache directory using the WordPress Filesystem API.
 *
 * @param string $file_path Absolute path to the destination file.
 * @param string $content   Data content to write.
 * @param bool   $append    Whether to append to the file if it exists.
 * @return bool True on success, false on failure.
 */
function wpsco_write_file( $file_path, $content, $append = false ) {
    $base_dir  = wp_normalize_path( wpsco_get_cache_dir() );
    $norm_path = wp_normalize_path( $file_path );

    // Ensure target path is strictly within the plugin's uploads directory.
    if ( strpos( $norm_path, $base_dir ) !== 0 ) {
        return false;
    }

    $dir = dirname( $norm_path );
    if ( ! is_dir( $dir ) ) {
        wp_mkdir_p( $dir );
    }

    global $wp_filesystem;
    if ( empty( $wp_filesystem ) ) {
        if ( ! function_exists( 'WP_Filesystem' ) && defined( 'ABSPATH' ) && file_exists( ABSPATH . 'wp-admin/includes/file.php' ) ) {
            require_once ABSPATH . 'wp-admin/includes/file.php';
        }
        if ( function_exists( 'WP_Filesystem' ) ) {
            WP_Filesystem();
        }
    }

    if ( $wp_filesystem && is_object( $wp_filesystem ) ) {
        if ( $append && $wp_filesystem->exists( $norm_path ) ) {
            $existing = $wp_filesystem->get_contents( $norm_path );
            return $wp_filesystem->put_contents( $norm_path, $existing . $content, FS_CHMOD_FILE );
        }
        return $wp_filesystem->put_contents( $norm_path, $content, FS_CHMOD_FILE );
    }

    // Fallback if WP_Filesystem could not be initialized.
    // phpcs:ignore WordPress.WP.AlternativeFunctions.file_system_operations_file_put_contents
    return false !== @file_put_contents( $norm_path, $content, $append ? ( FILE_APPEND | LOCK_EX ) : LOCK_EX );
}

/**
 * Safely read content from a file using the WordPress Filesystem API.
 *
 * @param string $file_path Absolute path to the file.
 * @return string|false File contents or false on failure.
 */
function wpsco_read_file( $file_path ) {
    if ( ! file_exists( $file_path ) ) {
        return false;
    }

    global $wp_filesystem;
    if ( empty( $wp_filesystem ) ) {
        if ( ! function_exists( 'WP_Filesystem' ) && defined( 'ABSPATH' ) && file_exists( ABSPATH . 'wp-admin/includes/file.php' ) ) {
            require_once ABSPATH . 'wp-admin/includes/file.php';
        }
        if ( function_exists( 'WP_Filesystem' ) ) {
            WP_Filesystem();
        }
    }

    if ( $wp_filesystem && is_object( $wp_filesystem ) ) {
        return $wp_filesystem->get_contents( $file_path );
    }

    // phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents
    return @file_get_contents( $file_path );
}

/**
 * Log a message.
 *
 * @param string $message Log message.
 * @param string $level   Log level (info, warning, error).
 */
function wpsco_log( $message, $level = 'info' ) {
    $log_dir  = wpsco_get_cache_dir( 'logs/' );
    $log_file = $log_dir . gmdate( 'Y-m-d' ) . '.log';

    $timestamp = gmdate( 'Y-m-d H:i:s' );
    $entry     = sprintf( "[%s] [%s] %s\n", $timestamp, strtoupper( $level ), $message );

    wpsco_write_file( $log_file, $entry, true );
}

/**
 * Get cache version string.
 *
 * @return string
 */
function wpsco_get_cache_version() {
    return get_option( 'wpsco_cache_version', md5( WPSCO_VERSION ) );
}

/**
 * Increment cache version (invalidates all generated assets).
 */
function wpsco_increment_cache_version() {
    update_option( 'wpsco_cache_version', md5( microtime( true ) . wp_rand() ) );
}

/**
 * Get human-readable file size.
 *
 * @param int $bytes Size in bytes.
 * @return string
 */
function wpsco_format_size( $bytes ) {
    if ( $bytes >= 1073741824 ) {
        return number_format( $bytes / 1073741824, 2 ) . ' GB';
    } elseif ( $bytes >= 1048576 ) {
        return number_format( $bytes / 1048576, 2 ) . ' MB';
    } elseif ( $bytes >= 1024 ) {
        return number_format( $bytes / 1024, 2 ) . ' KB';
    } else {
        return $bytes . ' bytes';
    }
}

/**
 * Get directory size recursively.
 *
 * @param string $dir Directory path.
 * @return int Size in bytes.
 */
function wpsco_get_dir_size( $dir ) {
    $size = 0;
    if ( ! is_dir( $dir ) ) {
        return $size;
    }

    $iterator = new RecursiveIteratorIterator(
        new RecursiveDirectoryIterator( $dir, RecursiveDirectoryIterator::SKIP_DOTS )
    );

    foreach ( $iterator as $file ) {
        if ( $file->isFile() ) {
            $size += $file->getSize();
        }
    }

    return $size;
}

/**
 * Delete directory contents recursively.
 *
 * @param string $dir    Directory path.
 * @param bool   $delete Whether to delete the directory itself.
 * @return bool
 */
function wpsco_delete_dir_contents( $dir, $delete = false ) {
    if ( ! is_dir( $dir ) ) {
        return false;
    }

    $norm_dir = function_exists( 'wp_normalize_path' ) ? wp_normalize_path( $dir ) : str_replace( '\\', '/', $dir );

    // Safety check: The directory MUST contain 'wp-speed-optimizer' or 'speednest' to ensure we never touch any outside directory.
    if ( false === strpos( $norm_dir, 'wp-speed-optimizer' ) && false === strpos( $norm_dir, 'speednest' ) ) {
        wpsco_log( 'Refused to delete directory outside plugin cache: ' . $dir, 'error' );
        return false;
    }

    global $wp_filesystem;
    if ( empty( $wp_filesystem ) ) {
        if ( ! function_exists( 'WP_Filesystem' ) && defined( 'ABSPATH' ) && file_exists( ABSPATH . 'wp-admin/includes/file.php' ) ) {
            require_once ABSPATH . 'wp-admin/includes/file.php';
        }
        if ( function_exists( 'WP_Filesystem' ) ) {
            WP_Filesystem();
        }
    }

    $cache_root = function_exists( 'wpsco_get_cache_dir' ) ? wpsco_get_cache_dir() : ( defined( 'WPSCO_CACHE_DIR' ) ? WPSCO_CACHE_DIR : '' );
    $root_norm  = function_exists( 'wp_normalize_path' ) ? wp_normalize_path( $cache_root ) : str_replace( '\\', '/', $cache_root );
    $is_root   = ( rtrim( $norm_dir, '/' ) === rtrim( $root_norm, '/' ) );

    $files = @scandir( $dir );
    if ( is_array( $files ) ) {
        foreach ( $files as $file ) {
            if ( '.' === $file || '..' === $file ) {
                continue;
            }

            // Always preserve root security files.
            if ( $is_root && in_array( $file, array( '.htaccess', 'index.php' ), true ) ) {
                continue;
            }

            $item_path = rtrim( $dir, '/' ) . '/' . $file;

            if ( is_dir( $item_path ) ) {
                wpsco_delete_dir_contents( $item_path, true );
            } else {
                wp_delete_file( $item_path );
            }
        }
    }

    if ( $delete && ! $is_root && is_dir( $dir ) ) {
        if ( ! empty( $wp_filesystem ) ) {
            $wp_filesystem->delete( $dir );
        }
    }

    clearstatcache();
    return true;
}

/**
 * Check if WooCommerce is active.
 *
 * @return bool
 */
function wpsco_is_woocommerce_active() {
    return class_exists( 'WooCommerce' );
}

/**
 * Check if Elementor is active.
 *
 * @return bool
 */
function wpsco_is_elementor_active() {
    return defined( 'ELEMENTOR_VERSION' );
}

/**
 * Check if this is a WooCommerce page that should not be cached.
 *
 * @return bool
 */
function wpsco_is_woocommerce_nocache_page() {
    if ( ! wpsco_is_woocommerce_active() ) {
        return false;
    }

    if ( function_exists( 'is_cart' ) && is_cart() ) {
        return true;
    }
    if ( function_exists( 'is_checkout' ) && is_checkout() ) {
        return true;
    }
    if ( function_exists( 'is_account_page' ) && is_account_page() ) {
        return true;
    }

    return false;
}

/**
 * Check if current request should be excluded from caching.
 *
 * @return bool
 */
function wpsco_is_cache_excluded() {
    // Never cache admin.
    if ( is_admin() ) {
        return true;
    }

    $req_uri = isset( $_SERVER['REQUEST_URI'] ) ? sanitize_text_field( wp_unslash( $_SERVER['REQUEST_URI'] ) ) : '';

    // Never cache login page.
    if ( strpos( $req_uri, 'wp-login.php' ) !== false ) {
        return true;
    }

    // Never cache previews, editor sessions, or explicit nocache requests.
    // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- Read-only inspection of preview and cache bypass query parameters.
    if ( isset( $_GET['preview'] ) || isset( $_GET['elementor-preview'] ) || isset( $_GET['nocache'] ) || isset( $_GET['purge'] ) || isset( $_GET['preview_id'] ) ) {
        return true;
    }

    // Never cache logged-in users (check both WordPress function and cookie).
    if ( function_exists( 'is_user_logged_in' ) && is_user_logged_in() ) {
        return true;
    }
    if ( ! empty( $_COOKIE ) ) {
        foreach ( $_COOKIE as $cookie_name => $cookie_val ) {
            if ( strpos( $cookie_name, 'wordpress_logged_in_' ) === 0 || strpos( $cookie_name, 'comment_author_' ) === 0 ) {
                return true;
            }
        }
    }

    // Never cache POST requests.
    $request_method = isset( $_SERVER['REQUEST_METHOD'] ) ? sanitize_text_field( wp_unslash( $_SERVER['REQUEST_METHOD'] ) ) : '';
    if ( 'POST' === $request_method ) {
        return true;
    }

    // Never cache AJAX requests.
    if ( wp_doing_ajax() ) {
        return true;
    }

    // Never cache REST API.
    if ( defined( 'REST_REQUEST' ) && REST_REQUEST ) {
        return true;
    }

    // Never cache cron.
    if ( wp_doing_cron() ) {
        return true;
    }

    // Never cache XML-RPC.
    if ( defined( 'XMLRPC_REQUEST' ) && XMLRPC_REQUEST ) {
        return true;
    }

    // Check for WooCommerce cookies.
    $wc_cookies = array( 'woocommerce_cart_hash', 'woocommerce_items_in_cart', 'wp_woocommerce_session_' );
    foreach ( $wc_cookies as $cookie ) {
        foreach ( $_COOKIE as $cookie_name => $cookie_value ) {
            if ( strpos( $cookie_name, $cookie ) === 0 && ! empty( $cookie_value ) ) {
                return true;
            }
        }
    }

    // Check URL exclusions.
    $settings   = wpsco_get_setting();
    $exclusions = isset( $settings['cache_exclusions'] ) ? $settings['cache_exclusions'] : array();
    $request    = $req_uri;

    // URL patterns.
    if ( ! empty( $exclusions['patterns'] ) ) {
        foreach ( $exclusions['patterns'] as $pattern ) {
            $regex = '#^' . str_replace( array( '*', '#' ), array( '.*', '\\#' ), $pattern ) . '$#i';
            if ( preg_match( $regex, $request ) ) {
                return true;
            }
        }
    }

    // Exact URLs.
    if ( ! empty( $exclusions['urls'] ) ) {
        foreach ( $exclusions['urls'] as $url ) {
            if ( trailingslashit( $request ) === trailingslashit( $url ) ) {
                return true;
            }
        }
    }

    // Cookie exclusions.
    if ( ! empty( $exclusions['cookies'] ) ) {
        foreach ( $exclusions['cookies'] as $cookie ) {
            foreach ( $_COOKIE as $cookie_name => $cookie_value ) {
                if ( strpos( $cookie_name, $cookie ) === 0 ) {
                    return true;
                }
            }
        }
    }

    return false;
}

/**
 * Get server type.
 *
 * @return string
 */
function wpsco_get_server_type() {
    $server_software = isset( $_SERVER['SERVER_SOFTWARE'] ) ? sanitize_text_field( wp_unslash( $_SERVER['SERVER_SOFTWARE'] ) ) : '';

    if ( stripos( $server_software, 'litespeed' ) !== false ) {
        if ( stripos( $server_software, 'openlitespeed' ) !== false ) {
            return 'openlitespeed';
        }
        return 'litespeed';
    }

    if ( stripos( $server_software, 'nginx' ) !== false ) {
        return 'nginx';
    }

    if ( stripos( $server_software, 'apache' ) !== false ) {
        return 'apache';
    }

    if ( stripos( $server_software, 'cloudflare' ) !== false ) {
        return 'cloudflare';
    }

    return 'unknown';
}

/**
 * Get OPcache status.
 *
 * @return array
 */
function wpsco_get_opcache_status() {
    $status = array(
        'enabled'          => false,
        'available'        => false,
        'memory_usage'     => null,
        'statistics'       => null,
        'can_reset'        => false,
        'reason'           => '',
    );

    if ( ! function_exists( 'opcache_get_status' ) ) {
        $status['reason'] = __( 'OPcache extension is not installed.', 'speednest' );
        return $status;
    }

    $status['available'] = true;

    $opcache_status = @opcache_get_status( false );
    if ( false === $opcache_status ) {
        $status['reason'] = __( 'OPcache is installed but disabled.', 'speednest' );
        return $status;
    }

    $status['enabled'] = ! empty( $opcache_status['opcache_enabled'] );

    if ( isset( $opcache_status['memory_usage'] ) ) {
        $status['memory_usage'] = $opcache_status['memory_usage'];
    }

    if ( isset( $opcache_status['opcache_statistics'] ) ) {
        $status['statistics'] = $opcache_status['opcache_statistics'];
    }

    $status['can_reset'] = function_exists( 'opcache_reset' )
        && $status['enabled']
        && ! ini_get( 'opcache.restrict_api' );

    if ( ! $status['can_reset'] && $status['enabled'] ) {
        $restrict = ini_get( 'opcache.restrict_api' );
        if ( $restrict ) {
            $status['reason'] = sprintf(
                /* translators: %s: opcache.restrict_api value */
                __( 'OPcache reset is restricted by opcache.restrict_api (%s).', 'speednest' ),
                $restrict
            );
        }
    }

    return $status;
}

/**
 * Sanitize a URL path for use in file operations.
 *
 * @param string $path URL path.
 * @return string Sanitized path.
 */
function wpsco_sanitize_cache_path( $path ) {
    // Remove dangerous characters.
    $path = preg_replace( '/[^a-zA-Z0-9\/_\-\.]/', '', $path );
    // Remove directory traversal.
    $path = str_replace( '..', '', $path );
    // Remove leading/trailing slashes.
    $path = trim( $path, '/' );
    return $path;
}

/**
 * Check if the request has query parameters that affect caching.
 *
 * @return bool
 */
function wpsco_has_query_string() {
    $query = isset( $_SERVER['QUERY_STRING'] ) ? sanitize_text_field( wp_unslash( $_SERVER['QUERY_STRING'] ) ) : '';

    if ( empty( $query ) ) {
        return false;
    }

    // Common analytics/tracking params to ignore.
    $ignore = array(
        'utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
        'fbclid', 'gclid', 'msclkid', 'mc_cid', 'mc_eid',
    );

    parse_str( $query, $params );
    $remaining = array_diff_key( $params, array_flip( $ignore ) );

    return ! empty( $remaining );
}

/**
 * Convert a URL or relative path to a local absolute filesystem path.
 * Strips query strings (?ver=...) and hash fragments (#...) so file_exists() succeeds.
 *
 * @param string $url URL to convert.
 * @return string|false File path or false if not resolvable.
 */
function wpsco_url_to_path( $url ) {
    if ( empty( $url ) || ! is_string( $url ) ) {
        return false;
    }

    // Strip query strings and hash anchors (e.g. ?ver=6.4, #svg).
    $url = strtok( $url, '?#' );

    // Handle protocol-relative URLs.
    if ( strpos( $url, '//' ) === 0 ) {
        $url = 'https:' . $url;
    }

    // Handle root-relative paths (/wp-content/...).
    if ( strpos( $url, '/' ) === 0 && strpos( $url, '//' ) !== 0 ) {
        $candidate = ABSPATH . ltrim( $url, '/' );
        if ( file_exists( $candidate ) ) {
            return $candidate;
        }

        // Check if relative to WP_CONTENT_DIR.
        if ( defined( 'WP_CONTENT_DIR' ) ) {
            $content_folder = basename( WP_CONTENT_DIR );
            if ( strpos( $url, '/' . $content_folder . '/' ) === 0 ) {
                $sub = substr( $url, strlen( '/' . $content_folder . '/' ) );
                $cand2 = WP_CONTENT_DIR . '/' . $sub;
                if ( file_exists( $cand2 ) ) {
                    return $cand2;
                }
            }
        }
    }

    // Check uploads directory.
    $uploads = wp_get_upload_dir();
    if ( ! empty( $uploads['baseurl'] ) && strpos( $url, $uploads['baseurl'] ) === 0 ) {
        $rel = substr( $url, strlen( $uploads['baseurl'] ) );
        return $uploads['basedir'] . $rel;
    }

    // Check wp-content URL.
    $content_url = content_url();
    if ( strpos( $url, $content_url ) === 0 ) {
        $rel = ltrim( substr( $url, strlen( $content_url ) ), '/' );
        return WP_CONTENT_DIR . '/' . $rel;
    }

    // Check site URL.
    $site_url = site_url();
    if ( strpos( $url, $site_url ) === 0 ) {
        $rel = ltrim( substr( $url, strlen( $site_url ) ), '/' );
        return ABSPATH . $rel;
    }

    // Check home URL.
    $home_url = home_url();
    if ( $home_url !== $site_url && strpos( $url, $home_url ) === 0 ) {
        $rel = ltrim( substr( $url, strlen( $home_url ) ), '/' );
        return ABSPATH . $rel;
    }

    return false;
}