import ActivityKit
import Foundation

@MainActor
final class LiveActivityManager {
    static let shared = LiveActivityManager()
    private init() {}

    private var currentActivity: Activity<SessionActivityAttributes>?

    /// Check if there's an active session and restart Live Activity if needed
    func restartLiveActivityIfNeeded(activeSession: ClimbSession?, gymName: String?) async {
        // If we have an active session but no Live Activity, restart it
        guard let activeSession = activeSession,
            let gymName = gymName,
            activeSession.status == .active
        else {
            return
        }

        // Check if we already have a running Live Activity
        if currentActivity != nil {
            print("ℹ️ Live Activity already running")
            return
        }

        print("🔄 Restarting Live Activity for existing session")
        await startLiveActivity(for: activeSession, gymName: gymName)
    }

    /// Call this when a ClimbSession starts to begin a Live Activity
    func startLiveActivity(for session: ClimbSession, gymName: String) async {
        print("🔴 Starting Live Activity for gym: \(gymName)")

        await endLiveActivity()

        let attributes = SessionActivityAttributes(
            gymName: gymName, startTime: session.startTime ?? session.date)
        let initialContentState = SessionActivityAttributes.ContentState(
            elapsed: 0,
            totalAttempts: 0,
            completedProblems: 0
        )

        do {
            let activity = try Activity<SessionActivityAttributes>.request(
                attributes: attributes,
                contentState: initialContentState,
                pushType: nil
            )
            self.currentActivity = activity
            print("✅ Live Activity started successfully: \(activity.id)")
        } catch {
            print("❌ Failed to start live activity: \(error)")
            print("Error details: \(error.localizedDescription)")

            // Check specific error types
            if error.localizedDescription.contains("authorization") {
                print("Authorization error - check Live Activity permissions in Settings")
            } else if error.localizedDescription.contains("content") {
                print("Content error - check ActivityAttributes structure")
            }
        }
    }

    /// Call this to update the Live Activity with new session progress
    func updateLiveActivity(elapsed: TimeInterval, totalAttempts: Int, completedProblems: Int) async
    {
        guard let currentActivity else {
            print("⚠️ No current activity to update")
            return
        }

        print(
            "🔄 Updating Live Activity - Attempts: \(totalAttempts), Completed: \(completedProblems)"
        )

        let updatedContentState = SessionActivityAttributes.ContentState(
            elapsed: elapsed,
            totalAttempts: totalAttempts,
            completedProblems: completedProblems
        )

        do {
            await currentActivity.update(using: updatedContentState, alertConfiguration: nil)
            print("✅ Live Activity updated successfully")
        } catch {
            print("❌ Failed to update live activity: \(error)")
        }
    }

    /// Call this when a ClimbSession ends to end the Live Activity
    func endLiveActivity() async {
        guard let currentActivity else {
            print("ℹ️ No current activity to end")
            return
        }

        print("🔴 Ending Live Activity: \(currentActivity.id)")

        do {
            await currentActivity.end(using: nil, dismissalPolicy: .immediate)
            self.currentActivity = nil
            print("✅ Live Activity ended successfully")
        } catch {
            print("❌ Failed to end live activity: \(error)")
            self.currentActivity = nil
        }
    }

    /// Check if Live Activities are available and authorized
    func checkLiveActivityAvailability() -> String {
        let authorizationInfo = ActivityAuthorizationInfo()
        let status = authorizationInfo.areActivitiesEnabled

        let message = """
            Live Activity Status:
            • Enabled: \(status)
            • Authorization: \(authorizationInfo.areActivitiesEnabled ? "Granted" : "Denied/Unknown")
            • Current Activity: \(currentActivity?.id.description ?? "None")
            """

        print(message)
        return message
    }

    /// Start periodic updates for Live Activity
    func startPeriodicUpdates(for session: ClimbSession, totalAttempts: Int, completedProblems: Int)
    {
        guard currentActivity != nil else { return }

        Task {
            while currentActivity != nil {
                let elapsed = Date().timeIntervalSince(session.startTime ?? session.date)
                await updateLiveActivity(
                    elapsed: elapsed,
                    totalAttempts: totalAttempts,
                    completedProblems: completedProblems
                )

                // Wait 30 seconds before next update
                try? await Task.sleep(nanoseconds: 30_000_000_000)
            }
        }
    }
}