package `in`.blogspot.kmvignesh.locationexample

import android.Manifest
import android.annotation.SuppressLint
import android.content.Context
import android.content.Intent
import android.content.pm.PackageManager
import android.location.Location
import android.location.LocationListener
import android.location.LocationManager
import android.os.Build
import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import android.provider.Settings
import android.widget.Toast
import kotlinx.android.synthetic.main.activity_main.*
import kotlin.math.asin

private const val PERMISSION_REQUEST = 10

class MainActivity : AppCompatActivity() {


    lateinit var locationManager: LocationManager
    private var hasGps = false
    private var hasNetwork = false
    private var locationGps: Location? = null
    private var locationNetwork: Location? = null

    private var permissions = arrayOf(Manifest.permission.ACCESS_FINE_LOCATION,
                                    Manifest.permission.ACCESS_COARSE_LOCATION)
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        disableView()
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            if (checkPermission(permissions)) {
                enableView()
            } else {
                requestPermissions(permissions, PERMISSION_REQUEST)
            }
        } else {
            enableView()
        }

    }

    private fun disableView() {
        btn_get_location.isEnabled = false
    }

    private fun enableView() {
        btn_get_location.isEnabled = true
        btn_get_location.setOnClickListener { getLocation()}
        Toast.makeText(this, "Done", Toast.LENGTH_SHORT).show()
    }

    @SuppressLint("MissingPermission")
    private fun getLocation() {
        locationManager = getSystemService(Context.LOCATION_SERVICE) as LocationManager
        hasGps = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)
        hasNetwork = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)
        if (hasGps || hasNetwork) {

            if (hasGps) {
                locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 5000, 0F, object : LocationListener {
                    override fun onLocationChanged(location: Location?) {
                        if (location != null) {
                            locationGps = location
                            tv_result.setText("\nLatitude : " + locationGps!!.latitude +
                                    "\nLongitude : " + locationGps!!.longitude)
                            tv_distance.setText(getDistanceBetweenTwoMembers(56.109551,
                                                                            47.479125,
                                                                            locationGps!!.latitude,
                                                                            locationGps!!.longitude).toString())
                        }
                    }
                    override fun onStatusChanged(provider: String?, status: Int, extras: Bundle?) {
                    }
                    override fun onProviderEnabled(provider: String?) {
                    }
                    override fun onProviderDisabled(provider: String?) {
                    }
                })

            }
            if (hasNetwork) {
                locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 5000, 0F, object : LocationListener {
                    override fun onLocationChanged(location: Location?) {
                        if (location != null) {
                            locationNetwork = location
                            tv_result.setText("\nLatitude : + {" + locationNetwork!!.latitude +
                                    "\nLongitude : " + locationNetwork!!.longitude)
                            tv_distance.setText(getDistanceBetweenTwoMembers(56.109551,
                                                                            47.479125,
                                                                            locationNetwork!!.latitude,
                                                                            locationNetwork!!.longitude).toString())
                        }
                    }
                    override fun onStatusChanged(provider: String?, status: Int, extras: Bundle?) {
                    }
                    override fun onProviderEnabled(provider: String?) {
                    }
                    override fun onProviderDisabled(provider: String?) {
                    }
                })
            }


        } else {
            startActivity(Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS))
        }
    }

    private fun checkPermission(permissionArray: Array<String>): Boolean {

        for (i in permissionArray.indices) {
            if (checkCallingOrSelfPermission(permissionArray[i]) == PackageManager.PERMISSION_DENIED)
                return false
        }
        return true
    }

    private fun getDistanceBetweenTwoMembers(latitude : Double, longitude : Double, latitude1: Double, longitude1: Double)
            : Double{
        val llatitude = latitude * kotlin.math.PI/180
        val llatitude1 = latitude1 * kotlin.math.PI/180
        val llongitude = longitude * kotlin.math.PI/180
        val llongitude1 = longitude1* kotlin.math.PI/180
        val firstTerm = kotlin.math.sin((llatitude-llatitude1)/2) * kotlin.math.sin((llatitude-llatitude1)/2)
        val secondTerm = kotlin.math.cos(llatitude)*
                kotlin.math.cos(llatitude1)*
                kotlin.math.sin((llongitude - llongitude1)/2)*
                kotlin.math.sin((llongitude - llongitude1)/2)
        val sqrt = kotlin.math.sqrt(firstTerm + secondTerm)
        return kotlin.math.round(2 * asin(sqrt) * 6367.444)
    }

}