import Foundation
import AVFoundation
import CoreLocation
import CoreMotion

/**
 * QUIXZOOM Capture Manager
 * 
 * Hanterar inspelning, telemetri och uppladdning.
 * 4 lägen: Recording, Guided, Mission, Adaptive
 */
class CaptureManager: NSObject, ObservableObject {
    
    // MARK: - Published Properties
    @Published var currentSession: CaptureSession?
    @Published var isRecording = false
    @Published var currentInstruction: AIInstruction?
    @Published var uploadProgress: Double = 0
    @Published var qualityScore: Double = 0
    @Published var gpsSignal: Double = 0
    
    // MARK: - Services
    private var captureSession: AVCaptureSession?
    private var videoOutput: AVCaptureMovieFileOutput?
    private var locationManager: CLLocationManager?
    private var motionManager: CMMotionManager?
    private var altimeter: CMAltimeter?
    
    // MARK: - Data
    private var telemetryTimer: Timer?
    private var frameCount = 0
    private var videoFileURL: URL?
    
    // MARK: - Constants
    private let telemetryRate = 10.0 // Hz
    private let videoQuality = AVCaptureSession.Preset.hd1920x1080
    
    // MARK: - Initialization
    override init() {
        super.init()
        setupLocationManager()
        setupMotionManager()
    }
    
    // MARK: - Session Management
    
    func startSession(mode: CaptureSession.CaptureMode, config: SessionConfig) {
        let session = CaptureSession(
            id: UUID().uuidString,
            missionId: generateMissionId(),
            startTime: Date(),
            endTime: nil,
            mode: mode,
            status: .preparing,
            config: config,
            frames: [],
            telemetry: [],
            path: [],
            instructions: [],
            qualityScore: 0,
            reliabilityScore: 0
        )
        
        currentSession = session
        
        // Starta kamera
        setupCamera()
        
        // Starta inspelning
        startRecording()
        
        // Starta telemetri
        startTelemetryCollection()
        
        currentSession?.status = .recording
        isRecording = true
        
        print("[CAPTURE] Session started: \(session.id)")
        print("[CAPTURE] Mode: \(mode.rawValue)")
        print("[CAPTURE] Mission ID: \(session.missionId)")
    }
    
    func stopSession() {
        stopRecording()
        stopTelemetryCollection()
        
        currentSession?.endTime = Date()
        currentSession?.status = .completed
        isRecording = false
        
        // Starta uppladdning
        uploadSession()
        
        print("[CAPTURE] Session stopped: \(currentSession?.id ?? "unknown")")
    }
    
    // MARK: - Camera Setup
    
    private func setupCamera() {
        captureSession = AVCaptureSession()
        captureSession?.sessionPreset = videoQuality
        
        guard let session = captureSession else { return }
        
        // Video input
        guard let videoDevice = AVCaptureDevice.default(.builtInWideAngleCamera, for: .video, position: .back),
              let videoInput = try? AVCaptureDeviceInput(device: videoDevice),
              session.canAddInput(videoInput) else {
            print("[CAPTURE] Failed to setup video input")
            return
        }
        
        session.addInput(videoInput)
        
        // Audio input
        guard let audioDevice = AVCaptureDevice.default(for: .audio),
              let audioInput = try? AVCaptureDeviceInput(device: audioDevice),
              session.canAddInput(audioInput) else {
            print("[CAPTURE] Failed to setup audio input")
            return
        }
        
        session.addInput(audioInput)
        
        // Video output
        let movieOutput = AVCaptureMovieFileOutput()
        guard session.canAddOutput(movieOutput) else {
            print("[CAPTURE] Failed to add movie output")
            return
        }
        
        session.addOutput(movieOutput)
        videoOutput = movieOutput
        
        // Starta session
        DispatchQueue.global(qos: .userInitiated).async {
            session.startRunning()
        }
    }
    
    private func startRecording() {
        guard let output = videoOutput else { return }
        
        let documentsPath = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
        let missionId = currentSession?.missionId ?? "unknown"
        videoFileURL = documentsPath.appendingPathComponent("\(missionId).mov")
        
        guard let url = videoFileURL else { return }
        
        output.startRecording(to: url, recordingDelegate: self)
        print("[CAPTURE] Recording started: \(url.lastPathComponent)")
    }
    
    private func stopRecording() {
        videoOutput?.stopRecording()
        print("[CAPTURE] Recording stopped")
    }
    
    // MARK: - Telemetry
    
    private func setupLocationManager() {
        locationManager = CLLocationManager()
        locationManager?.delegate = self
        locationManager?.desiredAccuracy = kCLLocationAccuracyBest
        locationManager?.allowsBackgroundLocationUpdates = true
        locationManager?.startUpdatingLocation()
    }
    
    private func setupMotionManager() {
        motionManager = CMMotionManager()
        motionManager?.accelerometerUpdateInterval = 1.0 / telemetryRate
        motionManager?.gyroUpdateInterval = 1.0 / telemetryRate
        motionManager?.magnetometerUpdateInterval = 1.0 / telemetryRate
    }
    
    private func startTelemetryCollection() {
        // Starta accelerometer
        if motionManager?.isAccelerometerAvailable == true {
            motionManager?.startAccelerometerUpdates()
        }
        
        // Starta gyroskop
        if motionManager?.isGyroAvailable == true {
            motionManager?.startGyroUpdates()
        }
        
        // Starta magnetometer
        if motionManager?.isMagnetometerAvailable == true {
            motionManager?.startMagnetometerUpdates()
        }
        
        // Starta höjdmätare
        if CMAltimeter.isRelativeAltitudeAvailable() {
            altimeter = CMAltimeter()
            altimeter?.startRelativeAltitudeUpdates(to: .main) { [weak self] data, error in
                // Hantera höjd-data
            }
        }
        
        // Samla telemetri med jämna intervall
        telemetryTimer = Timer.scheduledTimer(withTimeInterval: 1.0 / telemetryRate, repeats: true) { [weak self] _ in
            self?.collectTelemetry()
        }
    }
    
    private func stopTelemetryCollection() {
        telemetryTimer?.invalidate()
        telemetryTimer = nil
        
        motionManager?.stopAccelerometerUpdates()
        motionManager?.stopGyroUpdates()
        motionManager?.stopMagnetometerUpdates()
        altimeter?.stopRelativeAltitudeUpdates()
    }
    
    private func collectTelemetry() {
        guard let session = currentSession else { return }
        
        // GPS
        let location = locationManager?.location
        let gps = GPSPoint(
            latitude: location?.coordinate.latitude ?? 0,
            longitude: location?.coordinate.longitude ?? 0,
            accuracy: location?.horizontalAccuracy ?? 0,
            altitude: location?.altitude ?? 0,
            timestamp: Date()
        )
        
        // IMU
        let accelData = motionManager?.accelerometerData
        let gyroData = motionManager?.gyroData
        let magData = motionManager?.magnetometerData
        
        let imu = IMUData(
            accelerometer: XYZ(
                x: accelData?.acceleration.x ?? 0,
                y: accelData?.acceleration.y ?? 0,
                z: accelData?.acceleration.z ?? 0
            ),
            gyroscope: XYZ(
                x: gyroData?.rotationRate.x ?? 0,
                y: gyroData?.rotationRate.y ?? 0,
                z: gyroData?.rotationRate.z ?? 0
            ),
            magnetometer: magData != nil ? XYZ(
                x: magData!.magneticField.x,
                y: magData!.magneticField.y,
                z: magData!.magneticField.z
            ) : nil
        )
        
        // Kompass
        let compass = location?.course ?? 0
        
        // Skapa telemetri
        let telemetry = TelemetryData(
            timestamp: Date(),
            gps: gps,
            imu: imu,
            compass: compass,
            altitude: location?.altitude ?? 0
        )
        
        // Lägg till i session
        currentSession?.telemetry.append(telemetry)
        currentSession?.path.append(gps)
        
        // Uppdatera GPS-signal
        gpsSignal = min(1.0, 50.0 / (gps.accuracy + 1.0))
    }
    
    // MARK: - Upload
    
    private func uploadSession() {
        guard let session = currentSession else { return }
        
        currentSession?.status = .uploading
        
        // TODO: Implementera uppladdning till backend
        // 1. Ladda upp video-fil
        // 2. Ladda upp metadata (JSON)
        // 3. Bekräftelse från server
        
        print("[CAPTURE] Uploading session: \(session.id)")
        
        // Simulera uppladdning
        DispatchQueue.main.asyncAfter(deadline: .now() + 2) { [weak self] in
            self?.uploadProgress = 1.0
            self?.currentSession?.status = .completed
            print("[CAPTURE] Upload complete: \(session.id)")
        }
    }
    
    // MARK: - AI Instructions
    
    func handleInstruction(_ instruction: AIInstruction) {
        currentInstruction = instruction
        currentSession?.instructions.append(instruction)
        
        // Visa instruktion för användaren
        print("[CAPTURE] AI Instruction: \(instruction.text)")
    }
    
    func completeInstruction() {
        currentInstruction?.completed = true
        currentInstruction?.completedAt = Date()
        currentInstruction = nil
    }
    
    // MARK: - Helpers
    
    private func generateMissionId() -> String {
        let prefix = "QZ"
        let date = DateFormatter()
        date.dateFormat = "yyyyMMdd"
        let dateStr = date.string(from: Date())
        let random = String(format: "%04d", Int.random(in: 0...9999))
        return "\(prefix)-\(dateStr)-\(random)"
    }
}

// MARK: - AVCaptureFileOutputRecordingDelegate

extension CaptureManager: AVCaptureFileOutputRecordingDelegate {
    func fileOutput(_ output: AVCaptureFileOutput, didStartRecordingTo fileURL: URL, from connections: [AVCaptureConnection]) {
        print("[CAPTURE] Recording started to: \(fileURL.lastPathComponent)")
    }
    
    func fileOutput(_ output: AVCaptureFileOutput, didFinishRecordingTo outputFileURL: URL, from connections: [AVCaptureConnection], error: Error?) {
        if let error = error {
            print("[CAPTURE] Recording error: \(error.localizedDescription)")
        } else {
            print("[CAPTURE] Recording finished: \(outputFileURL.lastPathComponent)")
        }
    }
}

// MARK: - CLLocationManagerDelegate

extension CaptureManager: CLLocationManagerDelegate {
    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        // GPS-uppdateringar hanteras i collectTelemetry
    }
    
    func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
        print("[CAPTURE] GPS error: \(error.localizedDescription)")
    }
}