<?php
/**
 * Class: Settings Export/Import.
 *
 * Handles exporting and importing plugin settings.
 *
 * @package advanced-analytics
 *
 * @since 3.4.0
 */

declare(strict_types=1);

namespace ADVAN\Settings;

use ADVAN\Helpers\Settings;
use ADVAN\Helpers\Crons_Helper;
use ADVAN\Lists\Logs_List;
use ADVAN\Migration\Abstract_Migration;

// Exit if accessed directly.
if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

if ( ! class_exists( '\ADVAN\Settings\Settings_Export_Import' ) ) {
	/**
	 * Handles export and import of plugin settings.
	 *
	 * @since 3.4.0
	 */
	class Settings_Export_Import {

		/**
		 * Paths to sensitive fields for masking on export.
		 * Dot notation for nested arrays.
		 *
		 * @since 3.4.0
		 */
		private const SENSITIVE_EXPORT_PATHS = array(
			'smtp_password',
			'slack_notifications.all.auth_token',
			'telegram_notifications.all.auth_token',
		);

		/**
		 * Handle the reset-settings request.
		 *
		 * @return void
		 *
		 * @since 3.4.0
		 */
		public static function handle_reset() {
			if ( ! isset( $_REQUEST['reset-settings'] ) || ! \check_admin_referer( 'reset-plugin-settings', 'reset_nonce' ) ) {
				return;
			}

			\delete_option( ADVAN_SETTINGS_NAME );

			Crons_Helper::clear_events( ADVAN_PREFIX . 'request_table_clear' );
			Crons_Helper::clear_events( ADVAN_PREFIX . 'error_log_clear' );

			\wp_safe_redirect(
				\add_query_arg(
					array(
						'page'  => Logs_List::MENU_SLUG,
						'reset' => 'true',
					),
					\admin_url( 'admin.php' )
				)
			);
			exit;
		}

		/**
		 * Handle the export-settings request.
		 *
		 * @return void
		 *
		 * @since 3.4.0
		 */
		public static function handle_export() {
			if ( ! isset( $_REQUEST['export-settings'] ) || ! \check_admin_referer( 'export-plugin-settings', 'export_nonce' ) ) {
				return;
			}

			if ( ! \current_user_can( 'manage_options' ) ) {
				\wp_die( \esc_html__( 'Insufficient permissions.', '0-day-analytics' ) );
			}

			global $wpdb;

			$stored_options = $wpdb->get_results(
				$wpdb->prepare( 'SELECT option_name, option_value FROM ' . $wpdb->options . ' WHERE option_name = %s', \ADVAN_SETTINGS_NAME ),
				ARRAY_A
			);

			header( 'Cache-Control: public, must-revalidate' );
			header( 'Pragma: hack' );
			header( 'Content-Type: text/plain' );
			header( 'Content-Disposition: attachment; filename="' . ADVAN_TEXTDOMAIN . '-options-' . gmdate( 'dMy' ) . '.dat"' );

			if ( ! empty( $stored_options ) && isset( $stored_options[0]['option_value'] ) ) {
				$data = json_decode( $stored_options[0]['option_value'], true );
				if ( json_last_error() !== JSON_ERROR_NONE ) {
					$data = unserialize( $stored_options[0]['option_value'], array( 'allowed_classes' => false ) );
				}
				if ( is_array( $data ) ) {
					self::mask_sensitive_fields( $data );
				}
				if ( is_array( $data ) ) {
					$data['plugin_version'] = \ADVAN_VERSION;
				}
				echo \wp_json_encode( $data );
			} else {
				echo \wp_json_encode( array() );
			}
			die();
		}

		/**
		 * Handle the import (file upload) request.
		 *
		 * @return void
		 *
		 * @since 3.4.0
		 */
		public static function handle_import() {
			if ( ! isset( $_FILES[ Settings::SETTINGS_FILE_FIELD ] ) || ! \check_admin_referer( 'aadvana-plugin-data', 'aadvana-security' ) ) {
				return;
			}

			$options = array();
			if ( isset( $_FILES ) &&
				isset( $_FILES[ Settings::SETTINGS_FILE_FIELD ] ) &&
				isset( $_FILES[ Settings::SETTINGS_FILE_FIELD ]['error'] ) &&
				! $_FILES[ Settings::SETTINGS_FILE_FIELD ]['error'] > 0 &&
				isset( $_FILES[ Settings::SETTINGS_FILE_FIELD ]['tmp_name'] ) ) {

					\add_filter(
						'upload_mimes',
						function( $mimes ) {
							$mimes['dat'] = 'application/json';
							return $mimes;
						}
					);

				// Basic size limit (50KB) to avoid large payload abuse.
				if ( isset( $_FILES[ Settings::SETTINGS_FILE_FIELD ]['size'] ) && (int) $_FILES[ Settings::SETTINGS_FILE_FIELD ]['size'] > 51200 ) {
					$_FILES[ Settings::SETTINGS_FILE_FIELD ] = array();
				} else {
					$ft = \wp_check_filetype_and_ext(
						$_FILES[ Settings::SETTINGS_FILE_FIELD ]['tmp_name'],
						$_FILES[ Settings::SETTINGS_FILE_FIELD ]['name'],
						array(
							'json' => 'application/json',
							'txt'  => 'text/plain',
							'dat'  => 'application/json',
						)
					);
					if ( empty( $ft['ext'] ) || ! in_array( $ft['ext'], array( 'json', 'txt', 'dat' ), true ) ) {
						$_FILES[ Settings::SETTINGS_FILE_FIELD ] = array();
					} else {
						$path    = \sanitize_text_field( \wp_unslash( $_FILES[ Settings::SETTINGS_FILE_FIELD ]['tmp_name'] ) );
						$content = '';

						// Try WP_Filesystem first; fall back to native PHP on failure.
						try {
							global $wp_filesystem;
							if ( ! isset( $wp_filesystem ) || ! is_object( $wp_filesystem ) ) {
								\WP_Filesystem();
							}
							if ( isset( $wp_filesystem ) && is_object( $wp_filesystem ) && $wp_filesystem->exists( $path ) ) {
								$tmp = $wp_filesystem->get_contents( $path );
								if ( false !== $tmp && '' !== $tmp ) {
									$content = (string) $tmp;
								}
							}
						} catch ( \Throwable $e ) {
							// Ignore and fall back below.
						}

						if ( '' === $content && \is_readable( $path ) ) {
							$content = @file_get_contents( $path ); // phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged,WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents
						}

						$options = array();
						if ( is_string( $content ) && '' !== $content ) {
							$options = json_decode( $content, true );
						}
						if ( ! is_array( $options ) ) {
							$options = array();
						}
						if ( ! empty( $options ) ) {
							// Handle version migration from imported payload.
							if ( isset( $options['plugin_version'] ) && is_string( $options['plugin_version'] ) && '' !== trim( $options['plugin_version'] ) ) {
								try {
									$import_version_norm  = Abstract_Migration::normalize_version( (string) $options['plugin_version'] );
									$current_version_norm = Abstract_Migration::normalize_version( (string) \ADVAN_VERSION );
									if ( (int) $import_version_norm < (int) $current_version_norm ) {
										\update_option( Settings::SETTINGS_VERSION, \sanitize_text_field( $options['plugin_version'] ) );
									}
								} catch ( \Throwable $e ) {
									// Ignore malformed version strings.
								}
								unset( $options['plugin_version'] );
							}

							\remove_filter( 'sanitize_option_' . ADVAN_SETTINGS_NAME, array( Settings::class, 'collect_and_sanitize_options' ) );
							\update_option( ADVAN_SETTINGS_NAME, Settings_Sanitizer::collect_and_sanitize( $options, true ) );
						}
					}
				}
			}

			\wp_safe_redirect(
				\add_query_arg(
					array(
						'page'   => Logs_List::MENU_SLUG,
						'import' => 'true',
					),
					\admin_url( 'admin.php' )
				)
			);
			exit;
		}

		/**
		 * Process settings page requests (reset, export, import).
		 * Called from add_options_page when on a plugin settings page.
		 *
		 * @return void
		 *
		 * @since 3.4.0
		 */
		public static function process_requests() {
			if ( isset( $_REQUEST['reset-settings'] ) ) {
				self::handle_reset();
			} elseif ( isset( $_REQUEST['export-settings'] ) ) {
				self::handle_export();
			} elseif ( isset( $_FILES[ Settings::SETTINGS_FILE_FIELD ] ) ) {
				self::handle_import();
			}
		}

		/**
		 * Mask sensitive fields in an associative array using dot-notated paths.
		 *
		 * @param array $data Data to process (modified in place).
		 *
		 * @return void
		 *
		 * @since 3.3.2
		 */
		public static function mask_sensitive_fields( array &$data ): void {
			if ( empty( $data ) || ! is_array( $data ) ) {
				return;
			}

			foreach ( self::SENSITIVE_EXPORT_PATHS as $path ) {
				if ( ! is_string( $path ) || '' === $path ) {
					continue;
				}
				$segments = explode( '.', $path );
				$ref      =& $data;
				$found    = true;
				foreach ( $segments as $seg ) {
					if ( is_array( $ref ) && array_key_exists( $seg, $ref ) ) {
						$ref =& $ref[ $seg ];
					} else {
						$found = false;
						break;
					}
				}
				if ( $found ) {
					$ref = '***';
				}
			}
		}
	}
}