Build widgets for the Smart Stack on Apple Watch

struct SimpleEntry: TimelineEntry {
    var date: Date
    var configuration: ConfigurationAppIntent
    var backyard: Backyard
    
    var bird: Bird? {
        return backyard.visitorEventForDate(date: date)?.bird
    }
    
    var waterDuration: Duration {
        return Duration.seconds(abs(self.date.distance(to: self.backyard.waterRefillDate)))
    }

    var foodDuration: Duration {
        return Duration.seconds(abs(self.date.distance(to: self.backyard.foodRefillDate)))
    }

    var relevance: TimelineEntryRelevance? {
        if let visitor = backyard.visitorEventForDate(date: date) {
            return TimelineEntryRelevance(score: 10, duration: visitor.endDate.timeIntervalSince(date))
        }
        return TimelineEntryRelevance(score: 0)
    }
}

func placeholder(in context: Context) -> SimpleEntry {
  return SimpleEntry(date: Date(), configuration: ConfigurationAppIntent(), backyard: Backyard.anyBackyard(modelContext: modelContext))
}

func snapshot(for configuration: ConfigurationAppIntent, in context: Context) async -> SimpleEntry {
  if let backyard = Backyard.backyardForID(modelContext: modelContext, backyardID: configuration.backyardID) {
    if let event = backyard.visitorEvents.first {
      return SimpleEntry(date: event.startDate, configuration: configuration, backyard: backyard)
    } else {
      return SimpleEntry(date: Date(), configuration: configuration, backyard: backyard)
    }
  }

  let yard = Backyard.anyBackyard(modelContext: modelContext)
  return SimpleEntry(date: Date(), configuration: ConfigurationAppIntent(), backyard: yard)
}

struct BackyardBirdsWidgetEntryView: View {
    @Environment(\.widgetFamily) private var family
    var entry: SimpleEntry
    
    var body: some View {
        switch family {
        case .accessoryRectangular:
            RectangularBackyardView(entry: entry)
        default:
            Text(entry.date, style: .time)
        }
    }
}

struct RectangularBackyardView: View {
    var entry: SimpleEntry
    
    var body: some View {
        HStack {
            if let bird = entry.bird {
                ComposedBird(bird: bird)
                    .scaledToFit()
                    .widgetAccentable()
                    .frame(width: 50, height: 50)
                VStack(alignment: .leading) {
                    Text(bird.speciesName)
                        .font(.headline)
                        .foregroundStyle(bird.colors.wing.color)
                        .widgetAccentable()
                        .minimumScaleFactor(0.75)
                    Text(entry.backyard.name)
                        .minimumScaleFactor(0.75)
                    HStack {
                        Image(systemName: "drop.fill")
                        Text(entry.waterDuration, format: remainingHoursFormatter)
                        Image(systemName: "fork.knife")
                        Text(entry.foodDuration, format: remainingHoursFormatter)
                    }
                    .imageScale(.small)
                    .minimumScaleFactor(0.75)
                    .foregroundStyle(.secondary)
                }
                .frame(maxWidth: .infinity, alignment: .leading)
            } else {
                Image(.fountainFill)
                    .foregroundStyle(entry.backyard.backgroundColor)
                    .imageScale(.large)
                    .scaledToFit()
                    .widgetAccentable()
                    .frame(width: 50, height: 50)
                VStack(alignment: .leading) {
                    Text(entry.backyard.name)
                        .font(.headline)
                        .foregroundStyle(entry.backyard.backgroundColor)
                        .widgetAccentable()
                        .minimumScaleFactor(0.75)
                    HStack {
                        Image(systemName: "drop.fill")
                        Text(entry.waterDuration, format: remainingHoursFormatter)
                        Image(systemName: "fork.knife")
                        Text(entry.foodDuration, format: remainingHoursFormatter)
                    }
                    .imageScale(.small)
                    .minimumScaleFactor(0.75)
                    Text("\(entry.backyard.historicalEvents.count) visitors")
                        .minimumScaleFactor(0.75)
                        .foregroundStyle(.secondary)
                }
                .frame(maxWidth: .infinity, alignment: .leading)
            }
        }
        .containerBackground(entry.backyard.backgroundColor.gradient, for: .widget)
    }
}

func timeline(for configuration: ConfigurationAppIntent, in context: Context) async -> Timeline<SimpleEntry> {
  var entries: [SimpleEntry] = []

  if let backyard = Backyard.backyardForID(modelContext: modelContext, backyardID: configuration.backyardID) {
    for event in backyard.visitorEvents {
      let entry = SimpleEntry(date: event.startDate, configuration: configuration, backyard: backyard)
      entries.append(entry)
      let afterEntry = SimpleEntry(date: event.endDate, configuration: configuration, backyard: backyard)
      entries.append(afterEntry)
    }
  }
  return Timeline(entries: entries, policy: .atEnd)
}

func recommendations() -> [AppIntentRecommendation<ConfigurationAppIntent>] {
  var recs = [AppIntentRecommendation<ConfigurationAppIntent>]()

  for backyard in Backyard.allBackyards(modelContext: modelContext) {
    let configIntent = ConfigurationAppIntent()
    configIntent.backyardID = backyard.id.uuidString
    let gardenRecommendation = AppIntentRecommendation(intent: configIntent, description: backyard.name)
    recs.append(gardenRecommendation)
  }

  return recs
}

func updateBackyardRelevantIntents() async {
    let modelContext = ModelContext(DataGeneration.container)
    var relevantIntents = [RelevantIntent]()
    
    for backyard in Backyard.allBackyards(modelContext: modelContext) {

        let configIntent = ConfigurationAppIntent()
        configIntent.backyardID = backyard.id.uuidString
        let relevantFoodDateContext = RelevantContext.date(from: backyard.lowSuppliesDate(for: .food), to: backyard.expectedEmptyDate(for: .food))
        let relevantFoodIntent = RelevantIntent(configIntent, widgetKind: "BackyardVisitorsWidget", relevance: relevantFoodDateContext)
        relevantIntents.append(relevantFoodIntent)

        let relevantWaterDateContext = RelevantContext.date(from: backyard.lowSuppliesDate(for: .water), to: backyard.expectedEmptyDate(for: .water))
        let relevantWaterIntent = RelevantIntent(configIntent, widgetKind: "BackyardVisitorsWidget", relevance: relevantWaterDateContext)
        relevantIntents.append(relevantWaterIntent)
    }

    do {
        try await RelevantIntentManager.shared.updateRelevantIntents(relevantIntents)
    } catch { }
}

Task {
  await updateBackyardRelevantIntents()
  WidgetCenter.shared.reloadTimelines(ofKind: "BackyardVisitorsWidget")
}