[AltStoreCore] Refactors core AltStore logic into AltStoreCore framework

AltStoreCore will contain all shared AltStore code between AltStore and any app extensions. Initially, it includes all AltStore model logic.

AltStoreCore/Model/Source.swift

@@ -0,0 +1,172 @@
+//
+//  Source.swift
+//  AltStore
+//
+//  Created by Riley Testut on 7/30/19.
+//  Copyright © 2019 Riley Testut. All rights reserved.
+//
+
+import CoreData
+
+public extension Source
+{
+    #if ALPHA
+    static let altStoreIdentifier = "com.rileytestut.AltStore.Alpha"
+    #else
+    static let altStoreIdentifier = "com.rileytestut.AltStore"
+    #endif
+    
+    #if STAGING
+    
+    #if ALPHA
+    static let altStoreSourceURL = URL(string: "https://f000.backblazeb2.com/file/altstore-staging/sources/alpha/apps-alpha-staging.json")!
+    #else
+    static let altStoreSourceURL = URL(string: "https://f000.backblazeb2.com/file/altstore-staging/apps-staging.json")!
+    #endif
+    
+    #else
+    
+    #if ALPHA
+    static let altStoreSourceURL = URL(string: "https://alpha.altstore.io/")!
+    #else
+    static let altStoreSourceURL = URL(string: "https://apps.altstore.io/")!
+    #endif
+    
+    #endif
+}
+
+@objc(Source)
+public class Source: NSManagedObject, Fetchable, Decodable
+{
+    /* Properties */
+    @NSManaged public var name: String
+    @NSManaged public var identifier: String
+    @NSManaged public var sourceURL: URL
+    
+    @NSManaged public var error: NSError?
+    
+    /* Non-Core Data Properties */
+    public var userInfo: [ALTSourceUserInfoKey: String]?
+    
+    /* Relationships */
+    @objc(apps) @NSManaged public private(set) var _apps: NSOrderedSet
+    @objc(newsItems) @NSManaged public private(set) var _newsItems: NSOrderedSet
+    
+    @nonobjc public var apps: [StoreApp] {
+        get {
+            return self._apps.array as! [StoreApp]
+        }
+        set {
+            self._apps = NSOrderedSet(array: newValue)
+        }
+    }
+    
+    @nonobjc public var newsItems: [NewsItem] {
+        get {
+            return self._newsItems.array as! [NewsItem]
+        }
+        set {
+            self._newsItems = NSOrderedSet(array: newValue)
+        }
+    }
+    
+    private enum CodingKeys: String, CodingKey
+    {
+        case name
+        case identifier
+        case sourceURL
+        case userInfo
+        case apps
+        case news
+    }
+    
+    private override init(entity: NSEntityDescription, insertInto context: NSManagedObjectContext?)
+    {
+        super.init(entity: entity, insertInto: context)
+    }
+    
+    public required init(from decoder: Decoder) throws
+    {
+        guard let context = decoder.managedObjectContext else { preconditionFailure("Decoder must have non-nil NSManagedObjectContext.") }
+        guard let sourceURL = decoder.sourceURL else { preconditionFailure("Decoder must have non-nil sourceURL.") }
+        
+        super.init(entity: Source.entity(), insertInto: context)
+        
+        do
+        {
+            self.sourceURL = sourceURL
+            
+            let container = try decoder.container(keyedBy: CodingKeys.self)
+            self.name = try container.decode(String.self, forKey: .name)
+            self.identifier = try container.decode(String.self, forKey: .identifier)
+            
+            let userInfo = try container.decodeIfPresent([String: String].self, forKey: .userInfo)
+            self.userInfo = userInfo?.reduce(into: [:]) { $0[ALTSourceUserInfoKey($1.key)] = $1.value }
+            
+            let apps = try container.decodeIfPresent([StoreApp].self, forKey: .apps) ?? []
+            let appsByID = Dictionary(apps.map { ($0.bundleIdentifier, $0) }, uniquingKeysWith: { (a, b) in return a })
+            
+            for (index, app) in apps.enumerated()
+            {
+                app.sourceIdentifier = self.identifier
+                app.sortIndex = Int32(index)
+            }
+            self._apps = NSMutableOrderedSet(array: apps)
+            
+            let newsItems = try container.decodeIfPresent([NewsItem].self, forKey: .news) ?? []
+            for (index, item) in newsItems.enumerated()
+            {
+                item.sourceIdentifier = self.identifier
+                item.sortIndex = Int32(index)
+            }
+                                
+            for newsItem in newsItems
+            {
+                guard let appID = newsItem.appID else { continue }
+                
+                if let storeApp = appsByID[appID]
+                {
+                    newsItem.storeApp = storeApp
+                }
+                else
+                {
+                    newsItem.storeApp = nil
+                }
+            }
+            self._newsItems = NSMutableOrderedSet(array: newsItems)
+        }
+        catch
+        {
+            if let context = self.managedObjectContext
+            {
+                context.delete(self)
+            }
+            
+            throw error
+        }
+    }
+}
+
+public extension Source
+{
+    @nonobjc class func fetchRequest() -> NSFetchRequest<Source>
+    {
+        return NSFetchRequest<Source>(entityName: "Source")
+    }
+    
+    class func makeAltStoreSource(in context: NSManagedObjectContext) -> Source
+    {
+        let source = Source(context: context)
+        source.name = "AltStore"
+        source.identifier = Source.altStoreIdentifier
+        source.sourceURL = Source.altStoreSourceURL
+        
+        return source
+    }
+    
+    class func fetchAltStoreSource(in context: NSManagedObjectContext) -> Source?
+    {
+        let source = Source.first(satisfying: NSPredicate(format: "%K == %@", #keyPath(Source.identifier), Source.altStoreIdentifier), in: context)
+        return source
+    }
+}