Add ArchiveCategoryLinkable (#950)

It makes a category linkable!

Sources/Site/Music/UI/ArchiveCategoryLinkable.swift

@@ -0,0 +1,17 @@
+//
+//  ArchiveCategoryLinkable.swift
+//  site
+//
+//  Created by Greg Bolsinga on 10/5/24.
+//
+
+import SwiftUI
+
+struct ArchiveCategoryLinkable: ArchiveSharable, Linkable {
+  let vault: Vault
+  let category: ArchiveCategory
+
+  var subject: Text { Text(category.title) }
+  var message: Text { subject }
+  var url: URL? { vault.categoryURLMap[category] }
+}

Sources/Site/Music/UI/ArchiveSharable.swift

@@ -64,13 +64,3 @@ extension ArtistDigest: ArchiveSharable {
     Text(descriptor)
   }
 }
-
-extension ArchiveCategory: ArchiveSharable {
-  var subject: Text {
-    Text(self.title)
-  }
-
-  var message: Text {
-    Text(self.title)
-  }
-}

Sources/Site/Music/UI/ArchiveSharableModifier.swift

@@ -7,15 +7,14 @@
 
 import SwiftUI
 
-struct ArchiveSharableModifier<T: ArchiveSharable>: ViewModifier {
+struct ArchiveSharableModifier<T: ArchiveSharable & Linkable>: ViewModifier {
   let item: T?
-  let url: URL?
 
   func body(content: Content) -> some View {
     #if os(tvOS)
       content  // ShareLink not available on tvOS
     #else
-      if let url, let item {
+      if let item, let url = item.url {
         content
           .toolbar { ArchiveSharableToolbarContent(item: item, url: url) }
       } else {
@@ -27,10 +26,6 @@ struct ArchiveSharableModifier<T: ArchiveSharable>: ViewModifier {
 
 extension View {
   func archiveShare<T: ArchiveSharable & Linkable>(_ item: T?) -> some View {
-    modifier(ArchiveSharableModifier(item: item, url: item?.url))
-  }
-
-  func archiveShare<T: ArchiveSharable>(_ item: T?, url: URL?) -> some View {
-    modifier(ArchiveSharableModifier(item: item, url: url))
+    modifier(ArchiveSharableModifier(item: item))
   }
 }

Sources/Site/Music/UI/CategoryDetailModifier.swift

@@ -15,7 +15,7 @@ struct CategoryDetailModifier: ViewModifier {
   func body(content: Content) -> some View {
     NavigationStack(path: $path) {
       content
-        .archiveShare(category, url: vault.categoryURLMap[category])
+        .archiveShare(ArchiveCategoryLinkable(vault: vault, category: category))
         .musicDestinations(vault, path: path)
     }
   }