//
//  BridgeModule+Watch.swift
//  Werkout_ios
//
//  Created by Trey Tartt on 6/19/24.
//

import Foundation
import WatchConnectivity
import AVFoundation
import HealthKit
import os
import SharedCore

private let watchBridgeLogger = Logger(subsystem: "com.werkout.ios", category: "watch-bridge")

extension BridgeModule: WCSessionDelegate {
    private func send<Action: Encodable>(action: Action) {
        do {
            let data = try JSONEncoder().encode(action)
            send(data)
        } catch {
            watchBridgeLogger.error("Failed to encode watch action: \(error.localizedDescription, privacy: .public)")
        }
    }

    private func sendInExerciseAction(_ model: WatchPackageModel) {
        do {
            let action = PhoneToWatchActions.inExercise(model)
            let payload = try JSONEncoder().encode(action)
            guard payload != lastSentInExercisePayload else {
                return
            }
            lastSentInExercisePayload = payload
            send(payload)
        } catch {
            watchBridgeLogger.error("Failed to encode in-exercise watch action: \(error.localizedDescription, privacy: .public)")
        }
    }
    
    private func flushQueuedWatchMessages() {
        let queuedMessages = queuedWatchMessages.dequeueAll()
        guard queuedMessages.isEmpty == false else {
            return
        }
        queuedMessages.forEach { send($0) }
    }

    private func enqueueWatchMessage(_ data: Data) {
        let droppedCount = queuedWatchMessages.enqueue(data)
        if droppedCount > 0 {
            watchBridgeLogger.warning("Dropping oldest queued watch message to enforce queue cap")
        }
    }
    
    func sendResetToWatch() {
        lastSentInExercisePayload = nil
        send(action: PhoneToWatchActions.reset)
    }
    
    func sendStartWorkoutToWatch() {
        lastSentInExercisePayload = nil
        send(action: PhoneToWatchActions.startWorkout)
    }
    
    func sendWorkoutCompleteToWatch() {
        lastSentInExercisePayload = nil
        send(action: PhoneToWatchActions.endWorkout)
    }
    
    func sendCurrentExerciseToWatch() {
        if let currentExercise = currentWorkoutInfo.currentExercise,
           let duration = currentExercise.duration ,
           duration > 0 {
            let watchModel = WatchPackageModel(currentExerciseName: currentExercise.exercise.name, 
                                               currentExerciseID: currentExercise.id ?? -1,
                                               currentTimeLeft: currentExerciseTimeLeft,
                                               workoutStartDate: workoutStartDate ?? Date())
            sendInExerciseAction(watchModel)
        } else {
            if let currentExercise = currentWorkoutInfo.currentExercise,
               let reps = currentExercise.reps,
               reps > 0 {
                
                // if not a timer we need to set the watch display with number of reps
                // if timer it will set when timer updates
                let watchModel = WatchPackageModel(currentExerciseName: currentExercise.exercise.name, currentExerciseID: currentExercise.id ?? -1, currentTimeLeft: reps, workoutStartDate: self.workoutStartDate ?? Date())
                self.sendInExerciseAction(watchModel)
            }
        }
    }
    
    func session(_ session: WCSession, didReceiveMessageData messageData: Data) {
        do {
            let model = try WatchPayloadValidation.decode(WatchActions.self, from: messageData)
            DispatchQueue.main.async {
                switch model {
                case .nextExercise:
                    self.nextExercise()
                    AudioEngine.shared.playFinished()
                case .workoutComplete(let data):
                    do {
                        let finishModel = try WatchPayloadValidation.decode(WatchFinishWorkoutModel.self, from: data)
                        self.healthKitUUID = finishModel.healthKitUUID
                    } catch {
                        watchBridgeLogger.error("Rejected watch completion payload: \(error.localizedDescription, privacy: .public)")
                    }
                case .restartExercise:
                    self.restartExercise()
                case .previousExercise:
                    self.previousExercise()
                case .stopWorkout:
                    self.completeWorkout()
                case .pauseWorkout:
                    self.pauseWorkout()
                }
            }
        } catch {
            watchBridgeLogger.error("Rejected WatchActions payload: \(error.localizedDescription, privacy: .public)")
        }
    }
    
    
    func session(_ session: WCSession,
                 activationDidCompleteWith activationState: WCSessionActivationState,
                 error: Error?) {
        DispatchQueue.main.async {
            switch activationState {
            case .notActivated:
                watchBridgeLogger.info("Watch session notActivated")
            case .inactive:
                watchBridgeLogger.info("Watch session inactive")
            case .activated:
                watchBridgeLogger.info("Watch session activated")
                self.flushQueuedWatchMessages()
#if os(iOS)
                let workoutConfiguration = HKWorkoutConfiguration()
                workoutConfiguration.activityType = .functionalStrengthTraining
                workoutConfiguration.locationType = .indoor
                if WCSession.isSupported(), session.activationState == .activated, session.isWatchAppInstalled {
                    HKHealthStore().startWatchApp(with: workoutConfiguration, completion: { (success, error) in
                        if let error = error {
                            watchBridgeLogger.error("Failed to start watch app: \(error.localizedDescription, privacy: .public)")
                        }
                    })
                }
#endif
            @unknown default:
                watchBridgeLogger.error("Unknown WCSession activation state")
            }
        }
    }
#if os(iOS)
    func sessionDidBecomeInactive(_ session: WCSession) {
        
    }
    
    func sessionDidDeactivate(_ session: WCSession) {
        session.activate()
    }
#endif
    func send(_ data: Data) {
        guard WCSession.isSupported() else {
            return
        }
        
        guard session.activationState == .activated else {
            enqueueWatchMessage(data)
            session.activate()
            return
        }
#if os(iOS)
        guard session.isWatchAppInstalled else {
            return
        }
#else
        guard session.isCompanionAppInstalled else {
            return
        }
#endif
        if session.isReachable {
            session.sendMessageData(data, replyHandler: nil) { error in
                watchBridgeLogger.error("Cannot send watch message: \(error.localizedDescription, privacy: .public)")
                DispatchQueue.main.async {
                    self.enqueueWatchMessage(data)
                }
            }
        } else {
            session.transferUserInfo(["package": data])
        }
    }
}