djid_sirani_ios/Sirani/View/Survey/Hasil/HasilSurveyVC.swift

//
//  HasilSurveyVC.swift
//  Sirani
//
//  Created by Anhar Solehudin on 12/04/19.
//  Copyright © 2019 Anhar Solehudin. All rights reserved.
//

import UIKit

class HasilSurveyVC: UIViewController {

    // Outlets
    @IBOutlet weak var hasilSurveyTV: UITableView!
    @IBOutlet weak var noDataLayout: UIView!
    @IBOutlet weak var progressLoadingLayout: UIView!
    @IBOutlet weak var progressLoading: UIActivityIndicatorView!
    
    // String Message
    private let alertNoConnectionTitle = "Informasi"
    private let alertNoConnectionMsg = "Sepertinya Anda sedang tidak tersambung pada koneksi internet"
    private let alertNoConnectionActionYes = "OK"
    
    // Initialize
    private var presenter: HasilSurveyPresenter!
    private var dataList: [SurveyResult] =  [SurveyResult]()
    
    // Request Params
    private var cursor: Int = 0
    private var prev: Int = 0
    private var jenis: String = "1"
    private var columns: String = ""
    private var search: String = ""
    
    // Const
    private let hasilSurveyCellId = "hasilSurveyCellId"
    
    // Others
    private var loading = false
    private var firstDataSetLoaded = false
    private var lastDataLoadedEmpty = false
    
    // View Lifecycles
    override var preferredStatusBarStyle: UIStatusBarStyle {
        return .lightContent
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        hasilSurveyTV.delegate = self
        hasilSurveyTV.dataSource = self
        hasilSurveyTV.tableFooterView = UIView()
        
        presenter = HasilSurveyPresenter(siraniApiServices: SiraniApiServices())
    }
    
    override func viewWillAppear(_ animated: Bool) {
        presenter.attachView(view: self)
    }
    
    override func viewDidAppear(_ animated: Bool) {
        if !firstDataSetLoaded {
            loadData()
            firstDataSetLoaded = true
        }
    }
    
    override func viewDidDisappear(_ animated: Bool) {
        presenter.detachView()
    }
    
    // private functions
    private func loadData() {
        if !loading && !lastDataLoadedEmpty {
            if ConnectionHelper.isConnectedToNetwork() {
                presenter.loadData(jenis: jenis, columns: columns, cursor: cursor, prev: prev, search: search)
            } else {
                showNoConnection()
            }
        }
    }

    @IBAction func onBtnBackTap(_ sender: Any) {
        performSegue(withIdentifier: "unwindHasilSurveyToHomeSegueId", sender: self)
    }
    
}

// View Delegate Protocols
extension HasilSurveyVC: HasilSurveyViewDelegate {
    
    func showNoConnection() {
        let alertNoConnection = UIAlertController(
            title: alertNoConnectionTitle,
            message: alertNoConnectionMsg,
            preferredStyle: .alert
        )
        alertNoConnection.addAction(
            UIAlertAction(title: alertNoConnectionActionYes, style: .default, handler: nil)
        )
        self.present(alertNoConnection, animated: true, completion: nil)
    }
    
    func showLoading() {
        loading = true
        progressLoading.startAnimating()
        progressLoadingLayout.show()
    }
    
    func hideLoading() {
        loading = false
        progressLoading.stopAnimating()
        progressLoadingLayout.hide()
    }
    
    func showNoDataLayout() {
        if cursor == 0 {
            noDataLayout.show()
        }
    }
    
    func hideNoDataLayout() {
        noDataLayout.hide()
    }
    
    func setDataList(dataList: [SurveyResult]) {
        
        if cursor == 0 {
            noDataLayout.hide()
        }
        
        if dataList.count > 0 {
            hasilSurveyTV.beginUpdates()
            for data in dataList {
                self.dataList.append(data)
                hasilSurveyTV.insertRows(
                    at: [IndexPath(row: self.dataList.count-1, section: 0)],
                    with: .automatic
                )
            }
            hasilSurveyTV.endUpdates()
            let totalData = dataList.count
            cursor += totalData
        } else {
            lastDataLoadedEmpty = true
        }
    }
}

// UITableController Protocols
extension HasilSurveyVC: UITableViewDelegate, UITableViewDataSource, UIScrollViewDelegate {
    
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return dataList.count
    }
    
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        if tableView == hasilSurveyTV {
            if let cell = tableView.dequeueReusableCell(withIdentifier: hasilSurveyCellId, for: indexPath) as? HasilSurveyCell {
                
                let surveyResult = dataList[indexPath.row]
                cell.updateViews(surveyResult: surveyResult)
                
                return cell
            } else {
                return HasilSurveyCell()
            }
        } else {
            return HasilSurveyCell()
        }
    }
    
    func scrollViewDidScroll(_ scrollView: UIScrollView) {
        let threshold = 100
        let contentOffset = scrollView.contentOffset.y
        let maximumOffset = scrollView.contentSize.height - scrollView.frame.size.height;
        
        if !loading && (Int(maximumOffset - contentOffset) <= threshold) {
            loadData()
        }
    }
    
}