Rework storage structs, link preview

CHDataManagement/Model/Tag.swift

@@ -1,6 +1,8 @@
 import Foundation
 
-final class Tag: Item {
+class Tag: Item, LocalizedItem {
+
+    override var itemType: ItemType { .tag }
 
     @Published
     var isVisible: Bool
@@ -59,7 +61,7 @@ final class Tag: Item {
         localized(in: language).title
     }
 
-    override var itemType: ItemType {
+    override var itemReference: ItemReference {
         .tagPage(self)
     }
 
@@ -68,21 +70,35 @@ final class Tag: Item {
     }
 
     func remove(_ file: FileResource) {
-        english.remove(linkPreviewImage: file)
-        german.remove(linkPreviewImage: file)
+        english.linkPreview.remove(file)
+        german.linkPreview.remove(file)
     }
 }
 
-extension Tag: LocalizedItem {
-
-}
+// MARK: Storage
 
 extension Tag {
 
-    var file: TagFile {
-        .init(id: id,
-              isVisible: isVisible,
-              german: german.tagFile,
-              english: english.tagFile)
+    convenience init(context: LoadingContext, id: String, data: Data) {
+        self.init(
+            content: context.content,
+            id: id,
+            isVisible: data.isVisible ?? true,
+            german: .init(context: context, data: data.german),
+            english: .init(context: context, data: data.english))
+    }
+
+    struct Data: Codable {
+        // Defaults to true if unset
+        let isVisible: Bool?
+        let german: LocalizedTag.Data
+        let english: LocalizedTag.Data
+    }
+
+    var data: Data {
+        .init(
+            isVisible: isVisible ? nil : false,
+            german: german.data,
+            english: english.data)
     }
 }