//
//  ViewController.swift
//  Hospital
//
//  Created by Wojciech Miśta on 14/10/2019.
//  Copyright © 2019 Wojciech Miśta. All rights reserved.
//

import UIKit
import CoreLocation
import Foundation

struct Hospital {
    let lat: Double
    let long: Double
    let name: String
    let distance: Double
    let address: String
    let tags: [String]
}

class ViewController: UIViewController, CLLocationManagerDelegate, UITableViewDelegate, UITableViewDataSource {

    @IBOutlet weak var table: UITableView!
    @IBOutlet weak var userTextInput: UITextField!
    @IBOutlet weak var locateMeButton: UIButton!
    @IBOutlet weak var submitUserInputButton: UIButton!
    @IBOutlet weak var typeOfLocatingMethod: UISegmentedControl!
    let locationManager:CLLocationManager = CLLocationManager()
    let googleAPIUrl:String = "https://maps.googleapis.com/maps/api/place/nearbysearch/json"
    let APIKey:String = "AIzaSyBpMA5wLvKdtSl0Cv76VmxoYvvRn6mLCn4"
    let radius:Int = 500
    var wasDataFetched:Bool = false
    let session = URLSession.shared
    var userLat:Double = 0
    var userLong:Double = 0
    let decoder = JSONDecoder()
    var hospitals = [Hospital]()


    override func viewDidLoad() {
        super.viewDidLoad()
        toggleUIElements(status: false)
        locationManager.delegate = self
        table.isHidden = true
        table.dataSource = self
        table.delegate = self
        table.reloadData()
    }

    @IBAction func locateMeButtonPressed(_ sender: Any) {
        locationManager.requestWhenInUseAuthorization()
        locationManager.startUpdatingLocation()
        locationManager.distanceFilter = 100
    }

    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        for currentLocation in locations {
            userLat = currentLocation.coordinate.latitude
            userLong = currentLocation.coordinate.longitude
            fetchNearbyPlacesData(long: userLong, lat: userLat)
        }
    }

    func fetchNearbyPlacesData(long: Double, lat: Double) {
        if(!wasDataFetched) {
            let URLLocation = "\(googleAPIUrl)?location=\(lat),\(long)"
            let URLRadius = "\(URLLocation)&radius=\(radius)"
            let URLType = "\(URLRadius)&types=hospital"
            let finalURL:String = "\(URLType)&key=\(APIKey)"
            guard let url = URL(string: finalURL) else {return}
            let task = URLSession.shared.dataTask(with: url) { (data, response, error) in
            guard let dataResponse = data,
                      error == nil else {
                      print(error?.localizedDescription ?? "Response Error")
                      return }
                do{
                    let jsonResponse = try JSONSerialization.jsonObject(with:
                        dataResponse, options: []) as! [String: Any]

                    if let results = jsonResponse["results"] as? [[String: AnyObject]] {
                        for result in results {
                            var name:String = ""
                            var address:String = ""
                            var distance:Double = 0.0
                            var long:Double = 0.0
                            var lat:Double = 0.0
                            var tags:[String] = []

                            name = result["name"]! as! String

                            if let vicinity = result["vicinity"] {
                                address = vicinity as! String
                            }

                            if let types = result["types"] as? [String] {
                                tags = types
                            }

                            if let geometry = result["geometry"] as? [String: AnyObject] {
                                if let location = geometry["location"] as? [String: AnyObject] {
                                    long = location["lng"]! as! Double
                                    lat = location["lat"]! as! Double
                                    distance = self.calculateDistance(long1: location["lng"]! as! Double, lat1: location["lat"]! as! Double, long2: self.userLong, lat2: self.userLat)
                                }
                            }
                            self.hospitals.append(Hospital(lat: lat, long: long, name: name, distance: distance, address: address, tags: tags))
                        }
                        self.hospitals.sort { (hos1, hos2) in
                            return hos1.distance < hos2.distance
                        }
                        print(self.hospitals.count)
                        self.table.isHidden = false
                        DispatchQueue.main.async {
                            self.table.isHidden = false
                            self.table.reloadData()
                        }
                        //myArr.sort { (lhs, rhs) in return lhs.deadline < rhs.deadline }


                        for hospital in self.hospitals {
                            print(hospital)
                        }
                    }
                 } catch let parsingError {
                    print("Error", parsingError)
               }
            }
            task.resume()
        }
    }

    func calculateDistance(long1: Double, lat1: Double, long2: Double, lat2: Double) -> Double {
        let R:Float = 6371e3
        let radLat1 = deg2rad(lat1)
        let radLat2 = deg2rad(lat2)
        let phi = deg2rad(lat2-lat1)
        let lambda = deg2rad(long1-long2)
        let a = sin(phi/2) * sin(phi/2) + cos(radLat1) * cos(radLat2) * sin(lambda/2) * sin(lambda/2)
        let c = 2 * atan2(sqrt(a), sqrt(1-a))
        let d:Float = R * Float(c)
        return Double(d)
    }

    func deg2rad(_ number: Double) -> Double {
        return number * .pi / 180
    }

    func toggleUIElements(status: Bool) {
        locateMeButton.isHidden = status
        userTextInput.isHidden = !status
        submitUserInputButton.isHidden = !status
    }

    @IBAction func locatingMethodChange(_ sender: Any) {
        switch typeOfLocatingMethod.selectedSegmentIndex
        {
        case 0:
            toggleUIElements(status: false)
        case 1:
            toggleUIElements(status: true)
        default:
            toggleUIElements(status: false)
        }
    }

    func numberOfSectionsInTableView(tableView: UITableView) -> Int {
        return 1
    }
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        print("SELF", self.hospitals.count)
        print("NIE SELF", self.hospitals.count)
        return self.hospitals.count
     }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
         print("WYWOLALEM SIE XD")
         let myCell = tableView.dequeueReusableCell(withIdentifier: "hospitalTableCell", for: indexPath) as! HospitalTableCell
         let item = self.hospitals[indexPath.item]
         myCell.cellAddress.text = item.address
         myCell.cellTitle.text = item.name
         myCell.cellTags.text =  item.tags.joined(separator: ", ")
         myCell.cellDistance.text = String(round(item.distance)) + " m"
         print(item)
         return myCell
     }



}