//
//  Hexiwear application is used to pair with Hexiwear BLE devices
//  and send sensor readings to WolkSense sensor data cloud
//
//  Copyright (C) 2016 WolkAbout Technology s.r.o.
//
//  Hexiwear is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//
//  Hexiwear is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with this program.  If not, see <http://www.gnu.org/licenses/>.
//
//
//  DetectHexiwearTableViewController.swift
//

import UIKit
import CoreBluetooth

struct HexiwearPeripheral {
    let p: CBPeripheral
    let isOTAP: Bool
    let deviceName: String
    let rssi: NSNumber?
}

protocol HexiwearReconnection {
    func didReconnectPeripheral(peripheral: CBPeripheral)
    func didDisconnectPeripheral()
}

class DetectHexiwearTableViewController: UITableViewController {

    // BLE
    var centralManager : CBCentralManager!
    var hexiwearPeripherals: [HexiwearPeripheral] = []
    var selectedPeripheral: CBPeripheral!
    var isHEXIOTAP: Bool = false
    
    var dataStore: DataStore!
    var userCredentials: UserCredentials!
    var device: TrackingDevice!
    var mqttAPI: MQTTAPI!
    var titleForReadings: String?
    
    var skipButton: UIBarButtonItem!
    var refreshCont: UIRefreshControl!
    
    var disconnectOnSignOut: Bool = false
    var hexiwearReconnection: HexiwearReconnection?
    let progressHUD = JGProgressHUD(style: .Dark)


    override func viewDidLoad() {
        super.viewDidLoad()
        self.navigationController!.navigationBar.titleTextAttributes = [NSForegroundColorAttributeName: UIColor.whiteColor()]
        
        // Initialize central manager
        centralManager = CBCentralManager(delegate: self, queue: nil)

        self.refreshCont = UIRefreshControl()
        self.refreshCont.addTarget(self, action: #selector(DetectHexiwearTableViewController.refresh(_:)), forControlEvents: UIControlEvents.ValueChanged)
        self.tableView.addSubview(refreshCont)

        title = "Detect"

    }
    
    override func viewDidAppear(animated: Bool) {
        scanPeripherals()
    }

    func refresh(sender:AnyObject) {
        scanPeripherals()
        refreshCont.endRefreshing()
    }

    private func scanPeripherals() {
        hexiwearPeripherals = retrieveConnectedHexiwearPeripherals()
        tableView.reloadData()
        centralManager.scanForPeripheralsWithServices(nil, options: [CBCentralManagerScanOptionAllowDuplicatesKey:true])
    }
    
    private func retrieveConnectedHexiwearPeripherals() -> [HexiwearPeripheral] {
        return
            centralManager
                .retrieveConnectedPeripheralsWithServices([DIServiceUUID])
                .filter({$0.name == "HEXIWEAR"})
                .map { peri -> HexiwearPeripheral in
                    let deviceName = getDeviceNameForHexiSerial(peri.identifier.UUIDString)
                    return HexiwearPeripheral(p: peri, isOTAP: false, deviceName: deviceName, rssi: nil)
            }
    }
    
    private func getDeviceNameForHexiSerial(hexiSerial: String) -> String {
        let serialMappings = getSerialMappings()

        guard let wolkSerialForHexiSerial = device.findHexiAndWolkCombination(hexiSerial, hexiAndWolkSerials: serialMappings) else { return "" }
        
        return dataStore.getDeviceNameForSerial(wolkSerialForHexiSerial) ?? ""

    }
    
    // MARK: - Table view data source

    override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return hexiwearPeripherals.count
    }

    
    override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCellWithIdentifier("hexiwearCellNew", forIndexPath: indexPath) as! HexiwearTableViewCell

        guard indexPath.row < hexiwearPeripherals.count else {
            cell.titleLabel.text = ""
            cell.detailLabel.text = ""
            cell.signalLabel.text = ""
            return cell
        }
        
        // Configure the cell...
        let peri = hexiwearPeripherals[indexPath.row]
        if peri.isOTAP {
            cell.titleLabel?.text = peri.deviceName == "" ? "New HEXIWEAR OTAP" : peri.deviceName + " -- OTAP"
        }
        else {
            cell.titleLabel?.text = peri.deviceName == "" ? "New HEXIWEAR" : peri.deviceName
        }

        cell.detailLabel?.text = peri.p.identifier.UUIDString

        if let rssi = peri.rssi where rssi.doubleValue < 0.0 {
            cell.signalLabel?.text = getSignalLevel(rssi)
        }
        else {
            cell.signalLabel?.text = ""
        }

        return cell
    }

    func getSignalLevel(rssi: NSNumber) -> String {
        
        if rssi.doubleValue > -50.0 {
            return "●●●●"
        }
        else if rssi.doubleValue > -60.0 {
            return "●●●○"
        }
        else if rssi.doubleValue > -70.0 {
            return "●●○○"
        }
        else if rssi.doubleValue > -80.0 {
            return "●○○○"
        }
        else {
            return "○○○○"
        }
    }
    
    func failureHandler(failureReason: Reason) {
        delay(0.0) {
            self.progressHUD.dismiss()
            switch failureReason {
            case .Other(let err):
                print("Other error \(err.description)")
            default:
                print("Default error handler")
            }
        }
    }

    override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
        guard indexPath.row != hexiwearPeripherals.count else { return }
        
        centralManager.stopScan()
        
        let peri = hexiwearPeripherals[indexPath.row]
        selectedPeripheral = peri.p
        isHEXIOTAP = peri.isOTAP
        titleForReadings = peri.deviceName
        centralManager.connectPeripheral(selectedPeripheral, options: nil)
        
        progressHUD.textLabel.text = "Connecting to \(peri.deviceName)"
        progressHUD.showInView(self.view, animated: true)

    }
    
    override func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
        return 60.0
    }

    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        progressHUD.dismiss()

        if segue.identifier == "toHexiwearDeviceTable" {
            if let vc = segue.destinationViewController as? HexiwearTableViewController {
                vc.hexiwearPeripheral = selectedPeripheral
                vc.dataStore = self.dataStore
                if userCredentials.isDemoUser() {
                    vc.title = "DEMO"
                    vc.isDemoAccount = true
                }
                else {
                    vc.isDemoAccount = false
                    let onlineTitle = device.trackingIsOff ? " (cloud OFF)" : " (cloud ON)"
                    if let title = titleForReadings {
                        vc.title = title + onlineTitle
                    }
                    else {
                        vc.title = title
                    }
                }

                vc.trackingDevice = self.device
                vc.mqttAPI = self.mqttAPI
                vc.hexiwearDelegate = self
                hexiwearReconnection = vc
                
                let serialMappings = getSerialMappings()
                
                let hexiSerial = selectedPeripheral.identifier.UUIDString
                
                let (wolkSerialForHexiSerial, wolkPasswordForHexiSerial) = device.findWolkCredentials(hexiSerial, hexiAndWolkSerials: serialMappings)
                vc.wolkSerialForHexiserial = wolkSerialForHexiSerial
                vc.wolkPasswordForHexiserial = wolkPasswordForHexiSerial

                centralManager.stopScan()
            }
        }
        else if segue.identifier == "toOTAP" {
            if let vc = segue.destinationViewController as? FirmwareSelectionTableViewController {
                vc.peri = selectedPeripheral
                vc.hexiwearDelegate = self
                vc.otapDelegate = self
                centralManager.stopScan()
            }
        }
        else if segue.identifier == "toActivateDevice" {
            if let vc = segue.destinationViewController as? ActivateDeviceViewController {
                    vc.dataStore = self.dataStore
                    vc.selectedPeripheral = selectedPeripheral
                    vc.deviceActivationDelegate = self
            }
        }
        else if segue.identifier == "toSettingsBase" {
            if let nc = segue.destinationViewController as? BaseNavigationController,
                vc = nc.topViewController as? SettingaBaseTableViewController {
                    vc.title = "Cloud settings"
                    vc.dataStore = self.dataStore
                    vc.trackingDevice = self.device
                    vc.delegate = self
                    vc.isDemoUser = userCredentials.isDemoUser()
            }
        }
    }

    private func showAlertWithText (header : String = "Warning", message : String) {
        let alert = UIAlertController(title: header, message: message, preferredStyle: UIAlertControllerStyle.Alert)
        alert.addAction(UIAlertAction(title: "Ok", style: UIAlertActionStyle.Destructive, handler: nil))
        self.presentViewController(alert, animated: true, completion: nil)
    }

}


//MARK:- CBCentralManagerDelegate
extension DetectHexiwearTableViewController: CBCentralManagerDelegate {
    
    func centralManagerDidUpdateState(central: CBCentralManager) {
        if central.state == .PoweredOn {
            scanPeripherals()
        }
        else {
            showAlertWithText("Error", message: "Bluetooth not initialized")
        }
    }
    
    private func foundHexiwearIndex(p: CBPeripheral) -> (Bool, Int) {
        guard hexiwearPeripherals.count > 0 else { return (false, 0) }
        
        for i in 0..<hexiwearPeripherals.count {
            if hexiwearPeripherals[i].p == p {
                return (true, i)
            }
        }
        return (false, 0)
    }
    
    func centralManager(central: CBCentralManager, didDiscoverPeripheral peripheral: CBPeripheral, advertisementData: [String : AnyObject], RSSI: NSNumber) {
        let serialMappings = getSerialMappings()
        
        let hexiSerial = peripheral.identifier.UUIDString
        
        var deviceNameForSerial: String?
        if let wolkSerialForHexiSerial = device.findHexiAndWolkCombination(hexiSerial, hexiAndWolkSerials: serialMappings) {
            deviceNameForSerial = dataStore.getDeviceNameForSerial(wolkSerialForHexiSerial)
        }
        
        if Hexiwear.hexiotapFound(advertisementData) {
            appendOrReplacePeripheral(peripheral, isOTAP: true, deviceName: deviceNameForSerial ?? "", rssi: RSSI)
        }
        else if Hexiwear.hexiwearFound(advertisementData) {
            appendOrReplacePeripheral(peripheral, isOTAP: false, deviceName: deviceNameForSerial ?? "", rssi: RSSI)
        }
    }
    
    private func appendOrReplacePeripheral(peripheral: CBPeripheral, isOTAP: Bool, deviceName: String, rssi: NSNumber?) {
        let (found, index) = foundHexiwearIndex(peripheral)
        let newHexiwearPeripheral = HexiwearPeripheral(p: peripheral, isOTAP: isOTAP, deviceName: deviceName, rssi: rssi)
        if !found {
            hexiwearPeripherals.append(newHexiwearPeripheral)
            tableView.reloadData()
        }
        else {
            let offset = tableView.contentOffset.y + tableView.contentInset.top
            guard offset >= 0.0 else { return } // do not reload table while it is refreshing
            hexiwearPeripherals.replaceRange(index...index, with: [newHexiwearPeripheral])
            tableView.reloadData()
        }
    }
    
    func centralManager(central: CBCentralManager, didConnectPeripheral peripheral: CBPeripheral) {

        selectedPeripheral = peripheral

        // If device is reconnected while on readings screen, just drop any checking
        guard navigationController?.topMostViewController() == self else {
            progressHUD.dismiss()
            hexiwearReconnection?.didReconnectPeripheral(peripheral)
            return
        }

        // if user is logged in with demo account, skip cloud features (activation)
        guard userCredentials.isDemoUser() == false else {
            if self.isHEXIOTAP {
                self.performSegueWithIdentifier("toOTAP", sender: self)
            }
            else {
                self.performSegueWithIdentifier("toHexiwearDeviceTable", sender: self)
            }
            return
        }

        
        // Check device activation status...
        let serialMappings = getSerialMappings()

        let hexiSerial = peripheral.identifier.UUIDString
        
        // Activate device if there is no serial for selected hexiwear
        guard let wolkSerialForHexiSerial = device.findHexiAndWolkCombination(hexiSerial, hexiAndWolkSerials: serialMappings) else {
            self.dataStore.fetchAll(self.failureHandler) {
                dispatch_async(dispatch_get_main_queue()) {
                    // ... if it is not activated proceed to activation screen
                    self.performSegueWithIdentifier("toActivateDevice", sender: self)
                }
            }
            return
        }
        
        // If cloud is OFF
        guard device.trackingIsOff == false else {
            if self.isHEXIOTAP {
                self.performSegueWithIdentifier("toOTAP", sender: self)
            }
            else {
                self.performSegueWithIdentifier("toHexiwearDeviceTable", sender: self)
            }
            return
        }
        
        // If cloud is ON
        self.dataStore.getActivationStatusForSerial(wolkSerialForHexiSerial, onFailure: self.failureHandler) { activationStatus in
            dispatch_async(dispatch_get_main_queue()) {
                // ... if it is activated proceed to main screen
                if activationStatus == "ACTIVATED" {
                    dispatch_async(dispatch_get_main_queue()) {
                        if self.isHEXIOTAP {
                            self.performSegueWithIdentifier("toOTAP", sender: self)
                        }
                        else {
                            self.performSegueWithIdentifier("toHexiwearDeviceTable", sender: self)
                        }
                    }
                    return
                }
                
                self.dataStore.fetchAll(self.failureHandler) {
                    dispatch_async(dispatch_get_main_queue()) {
                        // ... if it is not activated proceed to activation screen
                        self.performSegueWithIdentifier("toActivateDevice", sender: self)
                    }
                }
            }
        }
    }
    
    func centralManager(central: CBCentralManager, didDisconnectPeripheral peripheral: CBPeripheral, error: NSError?) {
        
        if let error = error { print("didDisconnectPeripheral error: \(error)") }

        // If authentication is lost, drop readings processing
        if let err = error where err.domain == CBErrorDomain {
            let connectionFailedError: Int = CBError.ConnectionFailed.rawValue
            if err.code == connectionFailedError {
                print("connection failed")
            }
        }

        guard !disconnectOnSignOut else { return }

        if let _ = navigationController?.topMostViewController() as? FWUpgradeViewController {
            showSimpleAlertWithTitle(applicationTitle, message: "Hexiwear disconnected!", viewController: self, OKhandler: { _ in
                self.navigationController?.popToViewController(self, animated: true)
            })
        }
        else if let _ = navigationController?.topMostViewController() as? FirmwareSelectionTableViewController {
            showSimpleAlertWithTitle(applicationTitle, message: "Hexiwear disconnected!", viewController: self, OKhandler: { _ in
                self.navigationController?.popToViewController(self, animated: true)
            })
        }
        else if navigationController?.topMostViewController() != self { // reconnect
            hexiwearReconnection?.didDisconnectPeripheral()
            central.connectPeripheral(peripheral, options: nil)
        }

    }
    
    private func getSerialMappings() -> [SerialMapping] {
        let hexiAndWolkSerials = device.hexiAndWolkSerials
        
        let serialMappings = device.serialsStringToHexiAndWolkCombination(hexiAndWolkSerials)
        return serialMappings
    }
}


// MARK: - DeviceActivationDelegate
extension DetectHexiwearTableViewController: DeviceActivationDelegate {
    func didActivateDevice(pointId: Int, serials: SerialMapping) {
        print("DETECT HEXI -- didActivateDevice with serials: \(serials) and pointId: \(pointId)")

        // Get hexi and wolk serial mappings
        let serialMappings = getSerialMappings()

        // Filter out mapping new hexi serial (if there is one)
        var serialMappingsFiltered = serialMappings.filter { return $0.hexiSerial != serials.hexiSerial }
        
        // Add new hexi serial mapping
        serialMappingsFiltered.append(serials)
        
        // Save new mappings
        device.hexiAndWolkSerials = device.hexiAndWolkCombinationToString(serialMappingsFiltered)
        
        proceedToMainScreen()
    }
    
    func didSkipActivation() {
        navigationController?.popViewControllerAnimated(true)
        restartScanning()
    }
    
    func proceedToMainScreen() {
        dispatch_async(dispatch_get_main_queue()) {
            self.navigationController?.popViewControllerAnimated(false)
            let segueToPerform = self.isHEXIOTAP ? "toOTAP" : "toHexiwearDeviceTable"
            self.performSegueWithIdentifier(segueToPerform, sender: self)
        }
    }
    
    func restartScanning() {
        navigationController?.popToViewController(self, animated: true)
        if selectedPeripheral != nil {
            centralManager.cancelPeripheralConnection(selectedPeripheral)
            selectedPeripheral.delegate = nil
            selectedPeripheral = nil
        }
        mqttAPI.setAuthorisationOptions("", password: "")
        hexiwearPeripherals = []
        tableView.reloadData()
        scanPeripherals()
    }
}

extension DetectHexiwearTableViewController: HexiwearPeripheralDelegate {
    func didUnwind() {
        restartScanning()
    }
    
    func didLoseBonding() {
        let message = "Lost bonding with HEXIWEAR. Click OK to open Bluetooth settings and choose forget HEXIWEAR and try again."

        showOKAndCancelAlertWithTitle(applicationTitle, message: message, viewController: self, OKhandler: {_ in
            UIApplication.sharedApplication().openURL(NSURL(string:UIApplicationOpenSettingsURLString)!);
        })
        if selectedPeripheral != nil {
            centralManager.cancelPeripheralConnection(selectedPeripheral)
            selectedPeripheral.delegate = nil
            selectedPeripheral = nil
        }
        mqttAPI.setAuthorisationOptions("", password: "")
        hexiwearPeripherals = []
        tableView.reloadData()
        scanPeripherals()
        self.navigationController?.popToViewController(self, animated: true)
    }
    
    func willDisconnectOnSignOut() {
        if selectedPeripheral != nil {
            disconnectOnSignOut = true
            centralManager.cancelPeripheralConnection(selectedPeripheral)
            selectedPeripheral.delegate = nil
            selectedPeripheral = nil
        }
        mqttAPI.setAuthorisationOptions("", password: "")
        NSNotificationCenter.defaultCenter().postNotificationName(HexiwearDidSignOut, object: nil)

    }    
}

extension DetectHexiwearTableViewController: OTAPDelegate {
    func didCancelOTAP() {
        restartScanning()
    }
    
    func didFailedOTAP() {
        showSimpleAlertWithTitle(applicationTitle, message: "OTAP failed!", viewController: self, OKhandler: { _ in
            self.navigationController?.popToViewController(self, animated: true)
            self.restartScanning()
        })
    }
}

extension DetectHexiwearTableViewController : HexiwearSettingsDelegate {
    func didSignOut() {
        willDisconnectOnSignOut()
    }
    
    func didSetTime() {
        print("n/a")
    }
}