Storage: CoreData: CoreDataStorage implementation.

1Weather.xcodeproj/project.pbxproj

@@ -150,6 +150,7 @@
 		CE9F01BB261B31A6009BA500 /* CoreDataError.swift in Sources */ = {isa = PBXBuildFile; fileRef = CE9F01BA261B31A6009BA500 /* CoreDataError.swift */; };
 		CE9F01BE261B34C0009BA500 /* CoreDataAppModelConvertable.swift in Sources */ = {isa = PBXBuildFile; fileRef = CE9F01BD261B34C0009BA500 /* CoreDataAppModelConvertable.swift */; };
 		CE9F01C1261B3776009BA500 /* CoreDataUtils.swift in Sources */ = {isa = PBXBuildFile; fileRef = CE9F01C0261B3776009BA500 /* CoreDataUtils.swift */; };
+		CE9F01CC261C9A6E009BA500 /* AppData.swift in Sources */ = {isa = PBXBuildFile; fileRef = CE9F01CB261C9A6D009BA500 /* AppData.swift */; };
 		CEAD00A12577B2D5003596AD /* StuffThatIsPresentInTheMainProject.swift in Sources */ = {isa = PBXBuildFile; fileRef = CEAD00A02577B2D5003596AD /* StuffThatIsPresentInTheMainProject.swift */; };
 		CEAFF08325DFC67F00DF4EBF /* Location.swift in Sources */ = {isa = PBXBuildFile; fileRef = CEAFF08225DFC67F00DF4EBF /* Location.swift */; };
 		CEAFF08925DFC6B200DF4EBF /* CurrentWeather.swift in Sources */ = {isa = PBXBuildFile; fileRef = CEAFF08825DFC6B200DF4EBF /* CurrentWeather.swift */; };
@@ -332,6 +333,7 @@
 		CE9F01BA261B31A6009BA500 /* CoreDataError.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CoreDataError.swift; sourceTree = "<group>"; };
 		CE9F01BD261B34C0009BA500 /* CoreDataAppModelConvertable.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CoreDataAppModelConvertable.swift; sourceTree = "<group>"; };
 		CE9F01C0261B3776009BA500 /* CoreDataUtils.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CoreDataUtils.swift; sourceTree = "<group>"; };
+		CE9F01CB261C9A6D009BA500 /* AppData.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AppData.swift; sourceTree = "<group>"; };
 		CEAD00A02577B2D5003596AD /* StuffThatIsPresentInTheMainProject.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = StuffThatIsPresentInTheMainProject.swift; sourceTree = "<group>"; };
 		CEAFF08225DFC67F00DF4EBF /* Location.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Location.swift; sourceTree = "<group>"; };
 		CEAFF08825DFC6B200DF4EBF /* CurrentWeather.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CurrentWeather.swift; sourceTree = "<group>"; };
@@ -860,6 +862,7 @@
 		CE89628F26175DF400CA274A /* Objects */ = {
 			isa = PBXGroup;
 			children = (
+				CE9F01CB261C9A6D009BA500 /* AppData.swift */,
 				CE89629926175DF500CA274A /* Human */,
 				CE89629026175DF400CA274A /* Machine */,
 			);
@@ -1227,6 +1230,7 @@
 				CD593BDC2608CDF100C93428 /* Date+Now.swift in Sources */,
 				CD17C60225D15C8500EE884E /* CoordinatorProtocol.swift in Sources */,
 				CDA5542825EF734200A2E08C /* TodayCellFactory.swift in Sources */,
+				CE9F01CC261C9A6E009BA500 /* AppData.swift in Sources */,
 				CEF959742600C3A400975FAA /* FlurryAnalyticsService.swift in Sources */,
 				CE2847602615A8AD006C8DC5 /* BlendHealthSource.swift in Sources */,
 				CD86C22225F0DCCB00F38A16 /* PrecipitationView.swift in Sources */,

1Weather/Storage/CoreData/1WModel.xcdatamodeld/Model.xcdatamodel/contents

@@ -6,7 +6,7 @@
         <relationship name="health" optional="YES" maxCount="1" deletionRule="Nullify" destinationEntity="CoreHealth" inverseName="airQuality" inverseEntity="CoreHealth"/>
     </entity>
     <entity name="CoreAppData" representedClassName="CoreAppData" syncable="YES">
-        <attribute name="selectedIndex" optional="YES" attributeType="Integer 16" defaultValueString="0" usesScalarValueType="YES"/>
+        <attribute name="selectedIndex" optional="YES" attributeType="Decimal" defaultValueString="0"/>
         <relationship name="locations" toMany="YES" deletionRule="Cascade" ordered="YES" destinationEntity="CoreLocation" inverseName="appData" inverseEntity="CoreLocation"/>
     </entity>
     <entity name="CoreCurrentWeather" representedClassName="CoreCurrentWeather" syncable="YES">

1Weather/Storage/CoreData/CoreDataStorage.swift

@@ -29,34 +29,63 @@ public class CoreDataStorage: Storage {
             guard let context = self.managedContext else {
                 return
             }
-            self.deleteAll(in: context)
-            
+            do {
+                try self.deleteAll(in: context)
+                let appData = AppData(selectedIndex: selectedIndex, locations: locations)
+                if let coreAppData = try CoreAppData(context: context, appModel: appData) {
+                    context.insert(coreAppData)
+                    try self.save(context: context)
+                }
+            }
+            catch {
+                self.log.error("Error during saving: \(error)")
+            }
         }
     }
     
-    public func load(completion: StorageCompletion) {
-        managedContext?.perform {
-            
+    public func load(completion: @escaping StorageCompletion) {
+        managedContext?.perform { [weak self] in
+            guard let self = self else { return }
+            guard let context = self.managedContext else {
+                return
+            }
+            let completionOnMain: StorageCompletion = { (locations, selectedIndex, error) in
+                DispatchQueue.main.async {
+                    completion(locations, selectedIndex, error)
+                }
+            }
+            do {
+                let fetchRequest: NSFetchRequest<CoreAppData> = CoreAppData.fetchRequest()
+                fetchRequest.fetchLimit = 1
+                let results = try context.fetch(fetchRequest)
+                guard let coreAppData = results.first else {
+                    completionOnMain([], nil, nil)
+                    return
+                }
+                let appData: AppData = try coreAppData.toAppModel()
+                completionOnMain(appData.locations, appData.selectedIndex, nil)
+            }
+            catch  {
+                self.log.error("Error during load: \(error)")
+                completionOnMain(nil, nil, error)
+            }
         }
     }
     
-    private func deleteAll(in context: NSManagedObjectContext) {
-        #warning("Not implemented!")
-        //TODO: implement
+    private func deleteAll(in context: NSManagedObjectContext) throws {
+        let fetchRequest: NSFetchRequest<CoreAppData> = CoreAppData.fetchRequest()
+        let appDataObjects = try context.fetch(fetchRequest)
+        if appDataObjects.count > 1 {
+            log.warning("Somehow we ended up with more than 1 CoreAppData objects in the DB... deleting them all.")
+        }
+        for appData in appDataObjects {
+            context.delete(appData)
+        }
     }
     
-    private func saveContext() {
-        guard let context = managedContext else {
-            log.warning("saveContext: no context.")
-            return
-        }
+    private func save(context: NSManagedObjectContext) throws {
         if context.hasChanges {
-            do {
-                try context.save()
-            } catch {
-                let nserror = error as NSError
-                log.error("Error saving: \(nserror), \(nserror.userInfo)")
-            }
+            try context.save()
         }
     }
 }

1Weather/Storage/CoreData/Objects/AppData.swift

+//
+//  AppData.swift
+//  1Weather
+//
+//  Created by Demid Merzlyakov on 06.04.2021.
+//
+
+import Foundation
+
+
+/// A helper structure, so that we could work with CoreAppData the same way we work with everything else.
+public struct AppData {
+    public let selectedIndex: Int?
+    public let locations: [Location]
+}

1Weather/Storage/CoreData/Objects/Human/CoreAppData.swift

 import Foundation
+import CoreData
 
 @objc(CoreAppData)
-open class CoreAppData: _CoreAppData {
-	
+open class CoreAppData: _CoreAppData, CoreDataAppModelConvertable {
+    typealias AppModel = AppData
+    
+    func toAppModel() throws -> AppData {
+        var appModelLocations = [Location]()
+        try CoreDataUtils.foreach(in: self.locations, of: self, attributeName: "locations") { (coreLocation: CoreLocation) in
+            appModelLocations.append(try coreLocation.toAppModel())
+        }
+        
+        let result = AppModel(selectedIndex: self.selectedIndex?.intValue, locations: appModelLocations)
+        return result
+    }
+    
+    /// This is here just so that we could inherit the generated init(managedObjectContext) convenience initializer.
+    public override init(entity: NSEntityDescription, insertInto context: NSManagedObjectContext?) {
+        super.init(entity: entity, insertInto: context)
+    }
+    
+    required public init?(context: NSManagedObjectContext, appModel: AppData?) throws {
+        guard let appModel = appModel else {
+            return nil
+        }
+        self.init(managedObjectContext: context)
+        if let selectedIndex = appModel.selectedIndex {
+            self.selectedIndex = NSDecimalNumber(value: selectedIndex)
+        }
+        self.locations = NSOrderedSet(array: try appModel.locations.compactMap { try CoreLocation(context: context, appModel: $0)})
+    }
 }

1Weather/Storage/CoreData/Objects/Machine/_CoreAppData.swift

@@ -43,7 +43,7 @@ open class _CoreAppData: NSManagedObject {
     // MARK: - Properties
 
     @NSManaged open
-    var selectedIndex: Int16 // Optional scalars not supported
+    var selectedIndex: NSDecimalNumber?
 
     // MARK: - Relationships
 

1Weather/Storage/Storage.swift

@@ -7,9 +7,9 @@
 
 import Foundation
 
-public typealias StorageCompletion = ([Location]?, selectedIndex: Int, Error?)
+public typealias StorageCompletion = ([Location]?, Int?, Error?) -> ()
 
 public protocol Storage {
     func save(locations: [Location], selectedIndex: Int)
-    func load(completion: StorageCompletion)
+    func load(completion: @escaping StorageCompletion)
 }