#if os(iOS) && canImport(ActivityKit) && canImport(AppIntents) && canImport(WidgetKit)
import ActivityKit
import AppIntents
import SwiftUI
import WidgetKit

struct MailNotificationActivityAttributes: ActivityAttributes {
    struct ContentState: Codable, Hashable {
        var sender: String
        var initials: String
        var subject: String
        var preview: String
        var route: String
    }

    var threadRouteID: String
}

struct OpenMailLiveActivityIntent: LiveActivityIntent {
    static var title: LocalizedStringResource = "Open"
    static var openAppWhenRun = true

    @Parameter(title: "Route")
    var route: String

    init() {
        route = "socialio://mailbox/inbox"
    }

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

    func perform() async throws -> some IntentResult {
        .result()
    }
}

struct SnoozeMailLiveActivityIntent: LiveActivityIntent {
    static var title: LocalizedStringResource = "Snooze"

    func perform() async throws -> some IntentResult {
        .result()
    }
}

struct MailNotificationLiveActivity: Widget {
    var body: some WidgetConfiguration {
        ActivityConfiguration(for: MailNotificationActivityAttributes.self) { context in
            VStack(alignment: .leading, spacing: 10) {
                header(context: context)

                Text(context.state.preview)
                    .font(.caption)
                    .foregroundStyle(.secondary)
                    .lineLimit(2)

                HStack(spacing: 10) {
                    Button(intent: OpenMailLiveActivityIntent(route: context.state.route)) {
                        Text("Open")
                    }
                    .buttonStyle(.borderedProminent)

                    Button(intent: SnoozeMailLiveActivityIntent()) {
                        Text("Snooze")
                    }
                    .buttonStyle(.bordered)
                }
            }
            .padding(.vertical, 6)
        } dynamicIsland: { context in
            DynamicIsland {
                DynamicIslandExpandedRegion(.leading) {
                    Image(systemName: "envelope.fill")
                        .foregroundStyle(SIO.tint)
                }

                DynamicIslandExpandedRegion(.trailing) {
                    Text(context.state.initials)
                        .font(.headline.weight(.semibold))
                }

                DynamicIslandExpandedRegion(.center) {
                    VStack(alignment: .leading, spacing: 4) {
                        header(context: context)
                        Text(context.state.preview)
                            .font(.caption)
                            .foregroundStyle(.secondary)
                            .lineLimit(2)
                    }
                }

                DynamicIslandExpandedRegion(.bottom) {
                    HStack(spacing: 10) {
                        Button(intent: OpenMailLiveActivityIntent(route: context.state.route)) {
                            Text("Open")
                        }
                        .buttonStyle(.borderedProminent)

                        Button(intent: SnoozeMailLiveActivityIntent()) {
                            Text("Snooze")
                        }
                        .buttonStyle(.bordered)
                    }
                }
            } compactLeading: {
                Image(systemName: "envelope.fill")
            } compactTrailing: {
                Text(context.state.initials)
                    .font(.caption2.weight(.bold))
            } minimal: {
                Image(systemName: "envelope.fill")
            }
        }
    }

    @ViewBuilder
    private func header(context: ActivityViewContext<MailNotificationActivityAttributes>) -> some View {
        HStack(spacing: 10) {
            Text(context.state.initials)
                .font(.caption.weight(.bold))
                .foregroundStyle(SIO.tint)
                .frame(width: 28, height: 28)
                .background(SIO.tint.opacity(0.12), in: Circle())

            VStack(alignment: .leading, spacing: 2) {
                Text(context.state.sender)
                    .font(.subheadline.weight(.semibold))
                Text(context.state.subject)
                    .font(.caption)
                    .foregroundStyle(.secondary)
                    .lineLimit(1)
            }
        }
    }
}

#if !WIDGET_EXTENSION
enum MailNotificationActivityController {
    static func startIfNeeded(with thread: MailThread) async {
        guard ActivityAuthorizationInfo().areActivitiesEnabled else { return }

        let attributes = MailNotificationActivityAttributes(threadRouteID: thread.routeID)
        let state = MailNotificationActivityAttributes.ContentState(
            sender: thread.latestMessage?.sender.name ?? thread.participants.first?.name ?? "social.io",
            initials: initials(from: thread.latestMessage?.sender.name ?? thread.participants.first?.name ?? "SI"),
            subject: thread.subject,
            preview: thread.previewText,
            route: "socialio://open?thread=\(thread.routeID)"
        )

        if let existing = Activity<MailNotificationActivityAttributes>.activities.first {
            await existing.update(ActivityContent(state: state, staleDate: nil))
            return
        }

        _ = try? Activity<MailNotificationActivityAttributes>.request(
            attributes: attributes,
            content: ActivityContent(state: state, staleDate: nil)
        )
    }

    private static func initials(from name: String) -> String {
        String(name.split(separator: " ").prefix(2).compactMap { $0.first }).uppercased()
    }
}
#endif
#endif