// The watch face complication: how many threads are waiting on you, from `GET /v1/summary`. It
// reads the device token from the shared Keychain group and the demo flag from the App Group, and
// the app reloads it whenever its own feed or a notification changes the counts.

import SwiftUI
import WidgetKit

@main
struct WristCodeWidgets: WidgetBundle {
    var body: some Widget {
        WaitingWidget()
    }
}

struct WaitingWidget: Widget {
    var body: some WidgetConfiguration {
        StaticConfiguration(kind: "WaitingCount", provider: WaitingProvider()) { entry in
            WaitingView(entry: entry)
        }
        .configurationDisplayName("Waiting on you")
        .description("Threads waiting for your approval or answer.")
        .supportedFamilies([.accessoryCircular, .accessoryRectangular, .accessoryInline, .accessoryCorner])
    }
}

struct WaitingProvider: TimelineProvider {
    /// How long until WidgetKit asks again. The app reloads sooner when it learns something.
    static let refreshInterval: TimeInterval = 15 * 60

    func placeholder(in context: Context) -> WaitingEntry {
        .sample
    }

    func getSnapshot(in context: Context, completion: @escaping @Sendable (WaitingEntry) -> Void) {
        if context.isPreview {
            completion(.sample)
            return
        }
        Task { completion(await Self.load()) }
    }

    func getTimeline(in context: Context, completion: @escaping @Sendable (Timeline<WaitingEntry>) -> Void) {
        Task {
            let entry = await Self.load()
            completion(Timeline(entries: [entry], policy: .after(entry.date.addingTimeInterval(Self.refreshInterval))))
        }
    }

    static func load() async -> WaitingEntry {
        let api: any GatewayAPI
        if SharedState.demo {
            api = DemoGateway.shared
        } else if let credentials = DeviceStore.load() {
            api = GatewayClient(baseURL: credentials.gatewayURL, token: credentials.token)
        } else {
            return WaitingEntry(date: .now, content: .notPaired)
        }
        do {
            let summary = try await api.summary()
            SharedState.lastSummary = summary
            return WaitingEntry(date: .now, content: .counts(summary, stale: false))
        } catch GatewayError.unauthorized {
            return WaitingEntry(date: .now, content: .notPaired)
        } catch {
            guard let last = SharedState.lastSummary else { return WaitingEntry(date: .now, content: .unavailable) }
            return WaitingEntry(date: .now, content: .counts(last, stale: true))
        }
    }
}

private func entry(_ needsYou: Int, _ working: Int, next: Bool = true) -> WaitingEntry {
    let thread = Summary.Next(hostId: "mac-mini", threadId: "t-ocr", title: "Receipt OCR", hostLabel: "Mac mini")
    return WaitingEntry(date: .now, content: .counts(
        Summary(needsYou: needsYou, working: working, next: needsYou > 0 && next ? thread : nil, hostsOffline: 1),
        stale: false))
}

#Preview("Circular", as: .accessoryCircular) {
    WaitingWidget()
} timeline: {
    entry(2, 3)
    entry(0, 3)
    WaitingEntry(date: .now, content: .notPaired)
}

#Preview("Rectangular", as: .accessoryRectangular) {
    WaitingWidget()
} timeline: {
    entry(2, 3)
    entry(0, 3)
    WaitingEntry(date: .now, content: .notPaired)
}

#Preview("Inline", as: .accessoryInline) {
    WaitingWidget()
} timeline: {
    entry(2, 3)
}

#Preview("Corner", as: .accessoryCorner) {
    WaitingWidget()
} timeline: {
    entry(2, 3)
    entry(0, 3)
}