LocationManager: added location list.

1Weather/Model/LocationManager.swift

@@ -9,6 +9,7 @@ import Foundation
 
 public protocol LocationManagerDelegate: class {
     func locationManager(_ locationManager: LocationManager, changedCurrentLocation newLocation: Location?)
+    func locationManager(_ locationManager: LocationManager, updatedLocationsList newList: [Location])
 }
 
 public class LocationManager {
@@ -18,20 +19,36 @@ public class LocationManager {
     private let defaultLocation = Location(lastTimeUpdated: Date(),
                                            coordinates: .init(latitude: 37.3230, longitude: -122.0322), // Cupertino
                                            timeZone: TimeZone(abbreviation: "PST")!)
+    public private(set) var locations = [Location]() {
+        didSet {
+            log.info("Locations list updated: \(locations.map { $0.description }.joined(separator: ", "))")
+            DispatchQueue.main.async {
+                self.delegates.invoke { [weak self] (delegate) in
+                    guard let self = self else { return }
+                    delegate.locationManager(self, updatedLocationsList: self.locations)
+                }
+            }
+        }
+    }
+    
     private var _currentLocation: Location? {
         didSet {
             if oldValue?.description != currentLocation?.description {
                 log.info("Current location changed to: \(currentLocation?.description ?? "nil")")
             }
             log.info("Location updated.")
-            delegates.invoke { [weak self] (delegate) in
-                guard let self = self else { return }
-                delegate.locationManager(self, changedCurrentLocation: currentLocation)
+            DispatchQueue.main.async {
+                self.delegates.invoke { [weak self] (delegate) in
+                    guard let self = self else { return }
+                    delegate.locationManager(self, changedCurrentLocation: self.currentLocation)
+                }
             }
         }
     }
     
     public static let shared = LocationManager(weatherUpdateSource: WdtWeatherSource())
+    public let maxLocationsCount = 12
+    
     
     public init(weatherUpdateSource: WeatherSource) {
         self.weatherUpdateSource = weatherUpdateSource
@@ -40,6 +57,7 @@ public class LocationManager {
     public var currentLocation: Location? {
         get {
             guard let location = _currentLocation else {
+                // TODO: don't do it this way! We won't be able to show search if there's no location!
                 return defaultLocation
             }
             
@@ -56,7 +74,12 @@ public class LocationManager {
             log.warning("Update weather: no location.")
             return
         }
+        guard Date().timeIntervalSince(location.lastTimeUpdated) >= weatherUpdateSource.weatherUpdateInterval else {
+            log.info("Update weather: fresh enough (last updated at \(location.lastTimeUpdated)), skip update.")
+            return
+        }
         log.info("Update weather for location: \(location)")
+        
         weatherUpdateSource.updateWeather(for: location) { [weak self] (updatedLocation, error) in
             guard let self = self else { return }
             guard let updatedLocation = updatedLocation else {
@@ -74,6 +97,37 @@ public class LocationManager {
             }
         }
     }
+    // TODO: update weather for all locations
+    
+    public func add(location: Location) {
+        if locations.count >= maxLocationsCount {
+            log.warning("Adding new location, although the location limit is exceeded. New total: \(locations.count + 1)")
+            // This may happen if a location is added from a push notification.
+        }
+        if let existingLocation = locations.first(where: { $0 == location }) {
+            currentLocation = existingLocation
+        }
+        else {
+            locations.append(location)
+            currentLocation = location
+        }
+        // TODO: we need to update weather for new locations, probably.
+        // Or not? Should ViewModels handle it?
+    }
+    
+    public func remove(location: Location) {
+        if let index = locations.firstIndex(of: location) {
+            locations.remove(at: index)
+        }
+        else {
+            log.warning("Couldn't remove \(location), because we couldn't find index.")
+        }
+        if currentLocation == location {
+            currentLocation = locations.first
+        }
+    }
+    
+    // MARK: Delegates management
     
     public func add(delegate: LocationManagerDelegate) {
         delegates.add(delegate: delegate)

1Weather/Network/Weather/WdtWeatherSource.swift

@@ -21,6 +21,8 @@ public class WdtWeatherSource: WeatherSource {
     private static let updateUrlMega = "https://1weather.onelouder.com/feeds/onelouder/mega.php"
     private static let updateUrlMicro = "https://1weather.onelouder.com/feeds/onelouder2/fm.php"
     
+    public let weatherUpdateInterval = TimeInterval(15 * 60) // 15 minutes
+    
     public func updateWeather(for location: Location, completion: @escaping WeatherSourceCompletion) {
         log.debug("Start update.")
         guard var urlComponents = URLComponents(string: WdtWeatherSource.updateUrlMega) else {

1Weather/Network/Weather/WeatherSource.swift

@@ -10,5 +10,6 @@ import Foundation
 public typealias WeatherSourceCompletion = (Location?, Error?) -> ()
 
 public protocol WeatherSource {
+    var weatherUpdateInterval: TimeInterval { get }
     func updateWeather(for location: Location, completion: @escaping WeatherSourceCompletion)
 }

1Weather/ViewModels/TodayViewModel.swift

@@ -44,4 +44,8 @@ extension TodayViewModel: LocationManagerDelegate {
             self.delegate?.viewModelDidChange(model: self)
         }
     }
+    
+    func locationManager(_ locationManager: LocationManager, updatedLocationsList newList: [Location]) {
+        // do nothing
+    }
 }