NavigationDelegate.swift

import CoreLocation
import FerrostarCore
import FerrostarCoreFFI

/// Not all navigation apps will require a navigation delegate. In fact, we hope that most don't!
/// In case you do though, this sample implementation shows what you'll need to get started
/// by re-implementing the default behaviors of the core.
class NavigationDelegate: FerrostarCoreDelegate {
    func core(_: FerrostarCore, didStartWith _: Route) {
        // TODO: Create defaults extension on FerrostarCoreDelegate
    }

    func core(_: FerrostarCore, correctiveActionForDeviation _: DeviationKind,
              remainingWaypoints waypoints: [Waypoint]) -> CorrectiveAction
    {
        // If the user is off course, we'll try to calculate a new route using the remaining waypoints.
        .getNewRoutes(waypoints: waypoints)
    }

    func core(_ core: FerrostarCore, loadedAlternateRoutes routes: [Route]) {
        // Automatically accept the first new route if the framework was calculating a new route
        // due to the user being off course.
        // Pretty sensible default.
        if core.state?.isCalculatingNewRoute ?? false,
           let route = routes.first
        {
            do {
                // Most implementations will probably reuse existing configs (the default implementation does),
                // but we provide devs with flexibility here.
                let config = SwiftNavigationControllerConfig(
                    waypointAdvance: .waypointWithinRange(100.0),
                    stepAdvanceCondition: stepAdvanceDistanceEntryAndExit(
                        distanceToEndOfStep: 30,
                        distanceAfterEndOfStep: 2,
                        minimumHorizontalAccuracy: 32
                    ),
                    arrivalStepAdvanceCondition: stepAdvanceDistanceToEndOfStep(
                        distance: 30,
                        minimumHorizontalAccuracy: 32
                    ),
                    routeDeviationTracking: .staticThreshold(minimumHorizontalAccuracy: 25, maxAcceptableDeviation: 20),
                    snappedLocationCourseFiltering: .snapToRoute
                )
                try core.startNavigation(
                    route: route,
                    config: config
                )
            } catch {
                // Users of the framework my develop their own responses here, such as notifying the user if appropriate
            }
        }
    }
}