<?php
/**
 * Handles remote license verification and rules sync for Pro.
 */

defined( 'ABSPATH' ) || exit;

class ARSCAN_License {

    public static function maybe_refresh_license_state( array $settings, int $max_age = WEEK_IN_SECONDS, bool $preserve_on_error = true ): array {
        if ( empty( $settings['api_key'] ) ) {
            return $settings;
        }

        if ( ! self::is_license_check_stale( $settings, $max_age ) ) {
            return $settings;
        }

        return self::refresh_license_state_internal( $settings, $preserve_on_error );
    }

    public static function refresh_license_state( array $settings ): array {
        return self::refresh_license_state_internal( $settings, false );
    }

    private static function refresh_license_state_internal( array $settings, bool $preserve_on_error ): array {
        $settings['license_checked_at'] = current_time( 'mysql' );
        $settings['license_last_sync_message'] = '';

        if ( empty( $settings['api_key'] ) ) {
            return self::clear_license_state( $settings, __( 'No Pro API key saved.', 'agentreadyscan' ) );
        }

        $verify = self::verify_license( $settings['api_key'] );

        if ( is_wp_error( $verify ) ) {
            if ( $preserve_on_error ) {
                $settings['license_last_sync_message'] = sprintf(
                    /* translators: %s: request error message */
                    __( 'Automatic license recheck failed: %s', 'agentreadyscan' ),
                    $verify->get_error_message()
                );
                return $settings;
            }
            $settings['license_status'] = 'error';
            $settings['license_message'] = $verify->get_error_message();
            $settings['license_error_code'] = 'request_failed';
            return $settings;
        }

        if ( empty( $verify['valid'] ) ) {
            $settings['license_status'] = 'inactive';
            $settings['license_message'] = sanitize_text_field( $verify['message'] ?? __( 'License inactive.', 'agentreadyscan' ) );
            $settings['license_error_code'] = sanitize_key( $verify['error_code'] ?? 'inactive' );
            $settings['license_renewal_date'] = '';
            $settings['license_features'] = array();
            return $settings;
        }

        $settings['license_status'] = 'active';
        $settings['license_message'] = sanitize_text_field( $verify['message'] ?? __( 'Pro license active.', 'agentreadyscan' ) );
        $settings['license_error_code'] = '';
        $settings['license_renewal_date'] = sanitize_text_field( $verify['renewal_date'] ?? '' );
        $settings['license_features'] = self::sanitize_feature_list( $verify['unlocked_features'] ?? array() );

        $sync = self::sync_rules( $settings['api_key'] );
        if ( is_wp_error( $sync ) ) {
            $settings['license_last_sync_message'] = $sync->get_error_message();
            return $settings;
        }
        if ( isset( $sync['valid'] ) && false === $sync['valid'] ) {
            $settings['license_last_sync_message'] = sanitize_text_field(
                $sync['message'] ?? __( 'Rules sync is unavailable for this license.', 'agentreadyscan' )
            );
            return $settings;
        }

        $settings['license_last_sync_at'] = current_time( 'mysql' );
        $settings['license_last_sync_message'] = sanitize_text_field(
            sprintf(
                /* translators: %s: schema version */
                __( 'Rules synced from AgentReadyScan API (schema %s).', 'agentreadyscan' ),
                $sync['schema_version'] ?? 'unknown'
            )
        );

        return $settings;
    }

    public static function is_license_check_stale( array $settings, int $max_age = WEEK_IN_SECONDS ): bool {
        if ( empty( $settings['api_key'] ) ) {
            return false;
        }

        $last_checked = self::last_checked_timestamp( $settings );
        if ( ! $last_checked ) {
            return true;
        }

        return ( time() - $last_checked ) >= $max_age;
    }

    private static function last_checked_timestamp( array $settings ): int {
        $last_checked = trim( (string) ( $settings['license_checked_at'] ?? '' ) );
        if ( '' === $last_checked ) {
            return 0;
        }

        $timestamp = strtotime( $last_checked );
        return $timestamp ? (int) $timestamp : 0;
    }

    public static function clear_license_state( array $settings, string $message = '' ): array {
        $settings['license_status'] = 'inactive';
        $settings['license_message'] = $message;
        $settings['license_error_code'] = '';
        $settings['license_checked_at'] = current_time( 'mysql' );
        $settings['license_renewal_date'] = '';
        $settings['license_last_sync_at'] = '';
        $settings['license_last_sync_message'] = '';
        $settings['license_features'] = array();
        $settings['pro_health_status'] = '';
        $settings['pro_health_score'] = '';
        $settings['pro_health_checked_at'] = '';
        $settings['pro_health_issue_count'] = 0;
        $settings['pro_health_top_issues'] = array();
        $settings['pro_health_recommendations'] = array();
        $settings['pro_health_last_error'] = '';

        return $settings;
    }

    public static function verify_license( string $api_key ) {
        $response = wp_remote_post(
            self::api_url( '/v1/licenses/verify' ),
            array(
                'timeout' => 15,
                'headers' => array(
                    'Content-Type' => 'application/json',
                ),
                'body' => wp_json_encode(
                    array(
                        'api_key' => $api_key,
                        'domain' => wp_parse_url( home_url(), PHP_URL_HOST ),
                        'plugin_version' => ARSCAN_VERSION,
                    )
                ),
            )
        );

        return self::decode_json_response( $response );
    }

    public static function sync_rules( string $api_key ) {
        $response = wp_remote_get(
            self::api_url( '/v1/sync/rules' ),
            array(
                'timeout' => 15,
                'headers' => array(
                    'Authorization' => 'Bearer ' . $api_key,
                ),
            )
        );

        return self::decode_json_response( $response );
    }

    public static function create_billing_portal_session( string $api_key ) {
        $response = wp_remote_post(
            self::api_url( '/api/create-billing-portal-session' ),
            array(
                'timeout' => 15,
                'headers' => array(
                    'Content-Type' => 'application/json',
                ),
                'body' => wp_json_encode(
                    array(
                        'api_key' => $api_key,
                    )
                ),
            )
        );

        return self::decode_json_response( $response );
    }

    public static function sync_pro_snapshot( string $api_key, array $snapshot, string $settings_hash = '' ) {
        $response = wp_remote_post(
            self::api_url( '/v1/pro/snapshot' ),
            array(
                'timeout' => 20,
                'headers' => array(
                    'Content-Type'  => 'application/json',
                    'Authorization' => 'Bearer ' . $api_key,
                ),
                'body' => wp_json_encode(
                    array(
                        'plugin_version' => ARSCAN_VERSION,
                        'domain'         => wp_parse_url( home_url(), PHP_URL_HOST ),
                        'settings_hash'  => $settings_hash,
                        'snapshot'       => $snapshot,
                    )
                ),
            )
        );

        return self::decode_json_response( $response );
    }

    public static function fetch_latest_pro_audit( string $api_key ) {
        $domain = rawurlencode( (string) wp_parse_url( home_url(), PHP_URL_HOST ) );
        $response = wp_remote_get(
            self::api_url( '/v1/pro/audit/latest?domain=' . $domain ),
            array(
                'timeout' => 15,
                'headers' => array(
                    'Authorization' => 'Bearer ' . $api_key,
                ),
            )
        );

        return self::decode_json_response( $response );
    }

    private static function decode_json_response( $response ) {
        if ( is_wp_error( $response ) ) {
            return $response;
        }

        $status = (int) wp_remote_retrieve_response_code( $response );
        $body   = json_decode( wp_remote_retrieve_body( $response ), true );

        if ( ! is_array( $body ) ) {
            return new WP_Error( 'arscan_invalid_response', __( 'AgentReadyScan returned an unreadable response.', 'agentreadyscan' ) );
        }

        if ( $status >= 400 ) {
            $error_message = sanitize_text_field( $body['message'] ?? $body['error'] ?? __( 'License server returned an error.', 'agentreadyscan' ) );
            $error_code    = sanitize_key( $body['error_code'] ?? ( 'inactive' === ( $body['status'] ?? '' ) ? 'inactive' : 'server_error' ) );
            return new WP_Error( 'arscan_license_' . $error_code, $error_message );
        }

        return $body;
    }

    private static function api_url( string $path ): string {
        $base = untrailingslashit( apply_filters( 'arscan_api_base', ARSCAN_API_BASE ) );
        return $base . $path;
    }

    private static function sanitize_feature_list( $features ): array {
        if ( ! is_array( $features ) ) {
            return array();
        }

        $clean = array();
        foreach ( $features as $feature ) {
            $feature = sanitize_key( $feature );
            if ( '' !== $feature ) {
                $clean[] = $feature;
            }
        }

        return array_values( array_unique( $clean ) );
    }
}