FilteringViewController.swift

//
//  FilteringViewController.swift
//  Mapbox-iOS-Examples
//
//  Created by Roman Blum on 21.09.16.
//  Copyright © 2016 rmnblm. All rights reserved.
//

import UIKit
import Mapbox

class FilteringViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
    
    private let dataSource = FilteringDataSource()
    
    private var geoJSONSource: MGLShapeSource!
    
    @IBOutlet var mapView: MGLMapView!
    @IBOutlet var tableView: UITableView!
    
    private func loadData() {
        let geoJSONURL = Bundle.main.url(forResource: "siliconvalley", withExtension: "geojson")!
        
        geoJSONSource = MGLShapeSource(identifier: "sv", url: geoJSONURL)
        mapView.style?.addSource(geoJSONSource)
        
        for layer in dataSource.layers {
            let styleLayer = MGLSymbolStyleLayer(identifier: layer.title, source: geoJSONSource)
            styleLayer.predicate = layer.predicate
            //styleLayer.iconImage = MGLStyleConstantValue(rawValue: layer.name)
            mapView.style?.addLayer(styleLayer)
            
            layer.styleLayer = styleLayer
        }
    }
    
    // MARK: MGLMapViewDelegate
    
    public func mapViewDidFinishLoadingMap(_ mapView: MGLMapView) {
        loadData()
    }
    
    // MARK: UITableViewDataSource
    
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return dataSource.layers.count
    }
    
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        guard let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as? FilteringViewCell else {fatalError()}
        
        let layer = dataSource.layers[(indexPath as NSIndexPath).row]
        cell.titleLabel.text  = layer.title
        cell.stateSwitch.addTarget(self, action: #selector(filterStateChanged), for: UIControlEvents.valueChanged)
        cell.stateSwitch.tag = indexPath.row
        
        return cell
    }
    
    func filterStateChanged(sender: UISwitch) {
        let layer = dataSource.layers[sender.tag]
        layer.styleLayer.isVisible = sender.isOn
    }
    
    // MARK: UITableViewDelegate
    
    func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
        return UITableViewAutomaticDimension
    }
    
    func tableView(_ tableView: UITableView, estimatedHeightForRowAt indexPath: IndexPath) -> CGFloat {
        return UITableViewAutomaticDimension
    }
    
    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        let cell = tableView.cellForRow(at: indexPath) as! FilteringViewCell
        cell.stateSwitch.setOn(!cell.stateSwitch.isOn, animated: true)
        filterStateChanged(sender: cell.stateSwitch)
        
        tableView.deselectRow(at: indexPath, animated: true)
    }
}