import SwiftUI
import WidgetKit

#if os(iOS)
import ActivityKit
import AppIntents
import UIKit
#endif

struct ApprovalWidgetEntry: TimelineEntry {
    let date: Date
    let pendingCount: Int
    let topPayload: ApprovalActivityPayload?
}

struct ApprovalWidgetProvider: TimelineProvider {
    func placeholder(in context: Context) -> ApprovalWidgetEntry {
        ApprovalWidgetEntry(
            date: .now,
            pendingCount: 2,
            topPayload: ApprovalActivityPayload(
                requestID: UUID().uuidString,
                title: "github.com wants to sign in",
                appName: "github.com",
                source: "github.com",
                handle: "@jurgen",
                location: "Berlin, DE",
                createdAt: .now
            )
        )
    }

    func getSnapshot(in context: Context, completion: @escaping (ApprovalWidgetEntry) -> Void) {
        completion(makeEntry())
    }

    func getTimeline(in context: Context, completion: @escaping (Timeline<ApprovalWidgetEntry>) -> Void) {
        let entry = makeEntry()
        completion(Timeline(entries: [entry], policy: .after(.now.addingTimeInterval(60))))
    }

    private func makeEntry() -> ApprovalWidgetEntry {
        let state = UserDefaultsAppStateStore().load()
        let pendingRequests = (state?.requests ?? [])
            .filter { $0.status == .pending }
            .sorted { $0.createdAt > $1.createdAt }
        let handle = state?.profile.handle ?? "@you"

        return ApprovalWidgetEntry(
            date: .now,
            pendingCount: pendingRequests.count,
            topPayload: pendingRequests.first?.activityPayload(handle: handle)
        )
    }
}

@main
struct IDPGlobalWidgetsBundle: WidgetBundle {
    var body: some Widget {
        #if os(iOS)
        ApprovalLiveActivityWidget()
        #endif

        #if os(watchOS)
        ApprovalAccessoryRectangularWidget()
        ApprovalAccessoryCircularWidget()
        ApprovalAccessoryCornerWidget()
        #endif
    }
}

#if os(iOS)
struct ApproveLiveActivityIntent: LiveActivityIntent {
    static var title: LocalizedStringResource = "Approve"
    static var openAppWhenRun = false

    @Parameter(title: "Request ID")
    var requestID: String

    init() {}

    init(requestID: String) {
        self.requestID = requestID
    }

    func perform() async throws -> some IntentResult {
        guard let id = UUID(uuidString: requestID) else {
            return .result()
        }

        _ = try? await MockIDPService.shared.approveRequest(id: id)
        await ApprovalLiveActivityActionHandler.complete(requestID: requestID, outcome: "Approved")
        WidgetCenter.shared.reloadAllTimelines()
        return .result()
    }
}

struct DenyLiveActivityIntent: LiveActivityIntent {
    static var title: LocalizedStringResource = "Deny"
    static var openAppWhenRun = false

    @Parameter(title: "Request ID")
    var requestID: String

    init() {}

    init(requestID: String) {
        self.requestID = requestID
    }

    func perform() async throws -> some IntentResult {
        guard let id = UUID(uuidString: requestID) else {
            return .result()
        }

        _ = try? await MockIDPService.shared.rejectRequest(id: id)
        await ApprovalLiveActivityActionHandler.complete(requestID: requestID, outcome: "Denied")
        WidgetCenter.shared.reloadAllTimelines()
        return .result()
    }
}

private enum ApprovalLiveActivityActionHandler {
    static func complete(requestID: String, outcome: String) async {
        guard let activity = Activity<ApprovalActivityAttributes>.activities.first(where: { $0.attributes.requestID == requestID }) else {
            return
        }

        let state = ApprovalActivityAttributes.ContentState(
            requestID: requestID,
            title: outcome,
            appName: activity.content.state.appName,
            source: activity.content.state.source,
            handle: activity.content.state.handle,
            location: activity.content.state.location
        )

        await activity.end(ActivityContent(state: state, staleDate: .now), dismissalPolicy: .immediate)
    }
}

struct ApprovalLiveActivityWidget: Widget {
    var body: some WidgetConfiguration {
        ActivityConfiguration(for: ApprovalActivityAttributes.self) { context in
            VStack(alignment: .leading, spacing: 12) {
                Text(context.state.title)
                    .font(.headline)

                Text("Sign in as \(Text(context.state.handle).foregroundStyle(.purple))")
                    .font(.subheadline)

                Text(context.state.location)
                    .font(.caption)
                    .foregroundStyle(.secondary)

                HStack(spacing: 10) {
                    Button(intent: DenyLiveActivityIntent(requestID: context.state.requestID)) {
                        Text("Deny")
                    }
                    .buttonStyle(.bordered)

                    Button(intent: ApproveLiveActivityIntent(requestID: context.state.requestID)) {
                        Text("Approve")
                    }
                    .buttonStyle(.borderedProminent)
                    .tint(.purple)
                }
            }
            .padding(16)
            .activityBackgroundTint(Color(uiColor: .systemBackground))
            .activitySystemActionForegroundColor(.purple)
        } dynamicIsland: { context in
            DynamicIsland {
                DynamicIslandExpandedRegion(.leading) {
                    Image(systemName: "shield.lefthalf.filled")
                        .foregroundStyle(.purple)
                }
                DynamicIslandExpandedRegion(.trailing) {
                    MonogramBubble(title: context.state.appName)
                }
                DynamicIslandExpandedRegion(.center) {
                    VStack(alignment: .leading, spacing: 4) {
                        Text(context.state.title)
                            .font(.headline)
                        Text(context.state.handle)
                            .font(.caption)
                            .foregroundStyle(.secondary)
                    }
                }
                DynamicIslandExpandedRegion(.bottom) {
                    HStack(spacing: 10) {
                        Button(intent: DenyLiveActivityIntent(requestID: context.state.requestID)) {
                            Text("Deny")
                        }
                        .buttonStyle(.bordered)

                        Button(intent: ApproveLiveActivityIntent(requestID: context.state.requestID)) {
                            Text("Approve")
                        }
                        .buttonStyle(.borderedProminent)
                        .tint(.purple)
                    }
                }
            } compactLeading: {
                Image(systemName: "shield.lefthalf.filled")
                    .foregroundStyle(.purple)
            } compactTrailing: {
                MonogramBubble(title: context.state.appName)
            } minimal: {
                Image(systemName: "shield")
                    .foregroundStyle(.purple)
            }
        }
    }
}

private struct MonogramBubble: View {
    let title: String

    private var letter: String {
        String(title.trimmingCharacters(in: .whitespacesAndNewlines).first ?? "I").uppercased()
    }

    var body: some View {
        ZStack {
            Circle()
                .fill(Color.purple.opacity(0.18))
            Text(letter)
                .font(.caption.weight(.bold))
                .foregroundStyle(.purple)
        }
        .frame(width: 24, height: 24)
    }
}
#endif

#if os(watchOS)
struct ApprovalAccessoryRectangularWidget: Widget {
    var body: some WidgetConfiguration {
        StaticConfiguration(kind: "IDPGlobalAccessoryRectangular", provider: ApprovalWidgetProvider()) { entry in
            VStack(alignment: .leading, spacing: 3) {
                Label("idp.global", systemImage: "shield.lefthalf.filled")
                    .font(.caption2)

                Text("\(entry.pendingCount) requests")
                    .font(.headline)

                Text(entry.topPayload?.appName ?? "Inbox")
                    .font(.caption2)
                    .foregroundStyle(.secondary)
            }
            .widgetURL(URL(string: "idpglobal://inbox"))
        }
        .configurationDisplayName("Approval Queue")
        .description("Pending sign-in requests.")
        .supportedFamilies([.accessoryRectangular])
    }
}

struct ApprovalAccessoryCircularWidget: Widget {
    var body: some WidgetConfiguration {
        StaticConfiguration(kind: "IDPGlobalAccessoryCircular", provider: ApprovalWidgetProvider()) { entry in
            ZStack {
                AccessoryWidgetBackground()
                VStack(spacing: 2) {
                    Image(systemName: "shield.lefthalf.filled")
                    Text("\(entry.pendingCount)")
                        .font(.caption2.weight(.bold))
                }
            }
            .widgetURL(URL(string: "idpglobal://inbox"))
        }
        .configurationDisplayName("Approval Count")
        .supportedFamilies([.accessoryCircular])
    }
}

struct ApprovalAccessoryCornerWidget: Widget {
    var body: some WidgetConfiguration {
        StaticConfiguration(kind: "IDPGlobalAccessoryCorner", provider: ApprovalWidgetProvider()) { entry in
            Text("\(entry.pendingCount)")
                .widgetCurvesContent()
                .widgetLabel {
                    Image(systemName: "shield.lefthalf.filled")
                }
                .widgetURL(URL(string: "idpglobal://inbox"))
        }
        .configurationDisplayName("Approval Corner")
        .supportedFamilies([.accessoryCorner])
    }
}
#endif