<?php
/**
 * Privacy-minimised connected wizard journey milestones.
 *
 * The browser reports only a random session ID and allow-listed categories.
 * This boundary hashes the session before using the normal cron/outbox path.
 *
 * @package abtestkit
 */

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

/** Register the administrator-only local collection boundary. */
function abtestkit_connected_wizard_register_route() : void {
    register_rest_route(
        'abtestkit/v1',
        '/connected-wizard-milestone',
        array(
            'methods'             => 'POST',
            'permission_callback' => static function () : bool {
                return current_user_can( 'manage_options' );
            },
            'callback'            => 'abtestkit_connected_wizard_collect',
        )
    );
}
add_action( 'rest_api_init', 'abtestkit_connected_wizard_register_route' );

/**
 * Queue one unique reached-step event without making a service request.
 *
 * @param WP_REST_Request $request REST request.
 * @return WP_REST_Response|WP_Error
 */
function abtestkit_connected_wizard_collect( WP_REST_Request $request ) {
    if ( ! abtestkit_connected_platform_can_create_or_launch() ) {
        return abtestkit_connected_platform_required_error();
    }

    $input = $request->get_json_params();
    if ( ! is_array( $input ) ) {
        return new WP_Error( 'abtestkit_connected_wizard_invalid', __( 'The wizard milestone is invalid.', 'abtestkit' ), array( 'status' => 400 ) );
    }
    $keys = array_keys( $input );
    sort( $keys );
    if ( array( 'goal', 'kind', 'session_id', 'step' ) !== $keys ) {
        return new WP_Error( 'abtestkit_connected_wizard_invalid', __( 'The wizard milestone is invalid.', 'abtestkit' ), array( 'status' => 400 ) );
    }

    $session_id = is_string( $input['session_id'] ) ? $input['session_id'] : '';
    $step       = is_string( $input['step'] ) ? $input['step'] : '';
    $kind       = is_string( $input['kind'] ) ? $input['kind'] : '';
    $goal       = is_string( $input['goal'] ) ? $input['goal'] : '';
    if (
        1 !== preg_match( '/^ws_[a-f0-9]{32}$/D', $session_id ) ||
        ! in_array( $step, array( 'select_type', 'select_custom_code_type', 'select_control', 'version_b_source', 'review_versions', 'choose_conversion_type', 'set_destination_url', 'set_scroll_depth', 'select_click_targets', 'summary' ), true ) ||
        ! in_array( $kind, array( 'unknown', 'page', 'post', 'product', 'reusable_section', 'custom_css', 'custom_html', 'custom_javascript' ), true ) ||
        ! in_array( $goal, array( 'unknown', 'clicks', 'form', 'destination_url', 'scroll_depth', 'add_to_cart', 'purchase' ), true )
    ) {
        return new WP_Error( 'abtestkit_connected_wizard_invalid', __( 'The wizard milestone is invalid.', 'abtestkit' ), array( 'status' => 400 ) );
    }

    $connection   = abtestkit_hosted_get_connection();
    $installation = ABTestKit_Connected_Installation::get_or_create();
    if ( ! is_array( $connection ) || is_wp_error( $installation ) ) {
        abtestkit_connected_collection_gap( 'wizard_identity_unavailable' );
        return new WP_Error( 'abtestkit_connected_wizard_unavailable', __( 'The wizard milestone could not be recorded.', 'abtestkit' ), array( 'status' => 503 ) );
    }

    $site_ref = (string) ( $connection['site_ref'] ?? '' );
    if ( 1 !== preg_match( '/^[a-f0-9]{32}$/D', $site_ref ) ) {
        return new WP_Error( 'abtestkit_connected_wizard_unavailable', __( 'The wizard milestone could not be recorded.', 'abtestkit' ), array( 'status' => 503 ) );
    }

    $dedupe_key = 'abtestkit_wizard_event_' . hash( 'sha256', $site_ref . '|' . $session_id . '|' . $step );
    $record     = get_transient( $dedupe_key );
    if ( is_array( $record ) && true === ( $record['queued'] ?? false ) ) {
        return rest_ensure_response( array( 'accepted' => true ) );
    }

    if ( ! is_array( $record ) || ! isset( $record['event'] ) || ! is_array( $record['event'] ) ) {
        $event_id = ABTestKit_Connected_Event::new_id();
        if ( is_wp_error( $event_id ) ) {
            abtestkit_connected_collection_gap( $event_id->get_error_code() );
            return new WP_Error( 'abtestkit_connected_wizard_unavailable', __( 'The wizard milestone could not be recorded.', 'abtestkit' ), array( 'status' => 503 ) );
        }
        $session_ref = 'wizard_' . substr( hash_hmac( 'sha256', $site_ref . '|' . $session_id, (string) $installation['installation_id'] ), 0, 32 );
        $record      = array(
            'queued' => false,
            'event'  => array(
                'schema_version' => 1,
                'event_id'       => $event_id,
                'installation_id' => (string) $installation['installation_id'],
                'event_name'     => 'wizard_step_reached',
                'occurred_at'    => time(),
                'plugin_version' => abtestkit_hosted_sync_plugin_version(),
                'test_ref'       => null,
                'payload'        => array(
                    'evidence'    => 'observed',
                    'goal'        => $goal,
                    'kind'        => $kind,
                    'session_ref' => $session_ref,
                    'step'        => $step,
                ),
            ),
        );
        set_transient( $dedupe_key, $record, ABTestKit_Connected_Event::MAX_AGE );
    }

    $event = ABTestKit_Connected_Event::validate( $record['event'], time() );
    if ( is_wp_error( $event ) ) {
        delete_transient( $dedupe_key );
        abtestkit_connected_collection_gap( 'wizard_event_invalid' );
        return new WP_Error( 'abtestkit_connected_wizard_unavailable', __( 'The wizard milestone could not be recorded.', 'abtestkit' ), array( 'status' => 503 ) );
    }
    if ( 1 !== (int) get_option( ABTestKit_Connected_Outbox::SCHEMA_OPTION, 0 ) ) {
        $installed = ABTestKit_Connected_Outbox::install();
        if ( is_wp_error( $installed ) ) {
            abtestkit_connected_collection_gap( $installed->get_error_code() );
            return new WP_Error( 'abtestkit_connected_wizard_unavailable', __( 'The wizard milestone could not be recorded.', 'abtestkit' ), array( 'status' => 503 ) );
        }
    }
    $queued = ABTestKit_Connected_Outbox::enqueue( $event, time() );
    if ( is_wp_error( $queued ) ) {
        abtestkit_connected_collection_gap( $queued->get_error_code() );
        return new WP_Error( 'abtestkit_connected_wizard_unavailable', __( 'The wizard milestone could not be recorded.', 'abtestkit' ), array( 'status' => 503 ) );
    }

    $record['queued'] = true;
    set_transient( $dedupe_key, $record, ABTestKit_Connected_Event::MAX_AGE );
    abtestkit_connected_transport_schedule();
    return rest_ensure_response( array( 'accepted' => true ) );
}