<?php
/**
 * Connected onboarding evidence, separate from anonymous opt-in telemetry.
 * Only administrator actions queue events; the existing cron owns transport.
 *
 * @package abtestkit
 */

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

define( 'ABTESTKIT_CONNECTED_ONBOARDING_EVENT_PREFIX', 'abtestkit_connected_onboarding_event_' );

function abtestkit_connected_onboarding_event_key( string $site_ref, string $name ) : string {
    return ABTESTKIT_CONNECTED_ONBOARDING_EVENT_PREFIX . hash( 'sha256', $site_ref . '|' . $name );
}

/** Reserve a single immutable, site-level envelope before queueing it. */
function abtestkit_connected_onboarding_reserve( string $site_ref, string $name ) {
    $key = abtestkit_connected_onboarding_event_key( $site_ref, $name );
    $marker = get_option( $key, null );
    if ( null !== $marker ) {
        return $marker;
    }
    $installation = ABTestKit_Connected_Installation::get_or_create();
    $event_id = ABTestKit_Connected_Event::new_id();
    if ( is_wp_error( $installation ) || is_wp_error( $event_id ) ) {
        return new WP_Error( 'abtestkit_connected_onboarding_identity_unavailable' );
    }
    $event = array(
        'schema_version' => 1,
        'event_id' => $event_id,
        'installation_id' => (string) $installation['installation_id'],
        'event_name' => $name,
        'occurred_at' => time(),
        'plugin_version' => abtestkit_hosted_sync_plugin_version(),
        'test_ref' => null,
        'payload' => array( 'evidence' => 'observed' ),
    );
    if ( is_wp_error( ABTestKit_Connected_Event::validate( $event, time() ) ) ) {
        return new WP_Error( 'abtestkit_connected_onboarding_event_invalid' );
    }
    add_option( $key, array( 'event' => $event, 'acknowledged' => false ), '', 'no' );
    $marker = get_option( $key, null );
    return is_array( $marker ) ? $marker : new WP_Error( 'abtestkit_connected_onboarding_reservation_failed' );
}

/** Retry the exact envelope until accepted, or report its expiry honestly. */
function abtestkit_connected_onboarding_queue_marker( string $key, array $marker ) : bool {
    if ( ! is_bool( $marker['acknowledged'] ?? null ) || ! is_array( $marker['event'] ?? null ) ) {
        abtestkit_connected_collection_gap( 'onboarding_marker_invalid' );
        return false;
    }
    if ( $marker['acknowledged'] || ! empty( $marker['expired'] ) ) {
        return true;
    }
    if ( (int) ( $marker['event']['occurred_at'] ?? 0 ) <= time() - ABTestKit_Connected_Event::MAX_AGE ) {
        $marker['expired'] = true;
        update_option( $key, $marker, false );
        abtestkit_connected_collection_gap( 'onboarding_expired' );
        return false;
    }
    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 false;
        }
    }
    $queued = ABTestKit_Connected_Outbox::enqueue( $marker['event'], time() );
    if ( is_wp_error( $queued ) ) {
        abtestkit_connected_collection_gap( $queued->get_error_code() );
        return false;
    }
    return true;
}

/** First connected, eligible opening of the create-test wizard with no tests. */
function abtestkit_connected_onboarding_attempt() : void {
    if ( ! current_user_can( 'manage_options' ) || ! abtestkit_connected_platform_can_create_or_launch() ) {
        return;
    }
    $tests = get_option( 'abtestkit_page_tests', array() );
    if ( ! is_array( $tests ) || $tests ) {
        return;
    }
    abtestkit_connected_onboarding_observe( 'onboarding_started' );
}

/** First confirmed test creation, not a browser submit or shadow draft. */
function abtestkit_connected_onboarding_complete_after_test_created( string $test_id ) : void {
    if ( ! current_user_can( 'manage_options' ) || ! abtestkit_connected_platform_can_create_or_launch() ) {
        return;
    }
    $tests = get_option( 'abtestkit_page_tests', array() );
    if ( ! is_array( $tests ) || 1 !== count( $tests ) ) {
        return;
    }
    $saved_test = reset( $tests );
    if ( ! is_array( $saved_test ) || (string) ( $saved_test['id'] ?? '' ) !== $test_id ) {
        return;
    }
    abtestkit_connected_onboarding_observe( 'onboarding_completed' );
}

function abtestkit_connected_onboarding_observe( string $name ) : void {
    if ( ! in_array( $name, array( 'onboarding_started', 'onboarding_completed' ), true ) ) {
        return;
    }
    $connection = abtestkit_hosted_get_connection();
    if ( ! is_array( $connection ) ) {
        return;
    }
    $site_ref = (string) $connection['site_ref'];
    $key = abtestkit_connected_onboarding_event_key( $site_ref, $name );
    $marker = abtestkit_connected_onboarding_reserve( $site_ref, $name );
    if ( is_wp_error( $marker ) ) {
        abtestkit_connected_collection_gap( $marker->get_error_code() );
        return;
    }
    if ( ! is_array( $marker ) ) {
        abtestkit_connected_collection_gap( 'onboarding_marker_invalid' );
        return;
    }
    abtestkit_connected_onboarding_queue_marker( $key, $marker );
}

/** Recover pending one-shot events after queue loss or same-site reconnect. */
function abtestkit_connected_onboarding_reconcile() : void {
    if ( ! abtestkit_connected_platform_can_create_or_launch() ) {
        return;
    }
    $connection = abtestkit_hosted_get_connection();
    if ( ! is_array( $connection ) ) {
        return;
    }
    foreach ( array( 'onboarding_started', 'onboarding_completed' ) as $name ) {
        $key = abtestkit_connected_onboarding_event_key( (string) $connection['site_ref'], $name );
        $marker = get_option( $key, null );
        if ( is_array( $marker ) && empty( $marker['acknowledged'] ) && empty( $marker['expired'] ) ) {
            abtestkit_connected_onboarding_queue_marker( $key, $marker );
        } elseif ( null !== $marker && ! is_array( $marker ) ) {
            abtestkit_connected_collection_gap( 'onboarding_marker_invalid' );
        }
    }
}

/** Only a complete hosted response and local outbox acknowledgement finishes it. */
function abtestkit_connected_onboarding_mark_acknowledged( array $event, string $site_ref ) : void {
    $name = (string) ( $event['event_name'] ?? '' );
    if ( ! in_array( $name, array( 'onboarding_started', 'onboarding_completed' ), true ) ) {
        return;
    }
    $key = abtestkit_connected_onboarding_event_key( $site_ref, $name );
    $marker = get_option( $key, null );
    if ( ! is_array( $marker ) || ! hash_equals( (string) ( $marker['event']['event_id'] ?? '' ), (string) ( $event['event_id'] ?? '' ) ) ) {
        abtestkit_connected_collection_gap( 'onboarding_ack_marker_missing' );
        return;
    }
    $marker['acknowledged'] = true;
    update_option( $key, $marker, false );
    if ( get_option( $key, null ) !== $marker ) {
        abtestkit_connected_collection_gap( 'onboarding_ack_write_failed' );
    }
}