From 573761dcfa0b17d5cd171f485d538906e1c2321b Mon Sep 17 00:00:00 2001
From: John Estropia <rommel.estropia@gmail.com>
Date: Thu, 5 Dec 2024 16:36:47 +0900
Subject: [PATCH] handle more edge cases

---
 .../Preview/PreviewRegistryWrapper.swift      | 30 +++++++++++++++----
 1 file changed, 25 insertions(+), 5 deletions(-)

diff --git a/Sources/StorybookKit/Internals/Preview/PreviewRegistryWrapper.swift b/Sources/StorybookKit/Internals/Preview/PreviewRegistryWrapper.swift
index b40983b..c94af2a 100644
--- a/Sources/StorybookKit/Internals/Preview/PreviewRegistryWrapper.swift
+++ b/Sources/StorybookKit/Internals/Preview/PreviewRegistryWrapper.swift
@@ -20,7 +20,10 @@ struct PreviewRegistryWrapper: Comparable {
 
   @MainActor
   var makeView: (@MainActor () -> any View) {
-    let preview: FieldReader = .init(try! previewType.makePreview())
+    guard let rawPreview = try? previewType.makePreview() else {
+      return { EmptyView() }
+    }
+    let preview: FieldReader = .init(rawPreview)
     let title: String? = preview["displayName"]
     let source: FieldReader = preview["source"]
     switch source.typeName {
@@ -48,11 +51,28 @@ struct PreviewRegistryWrapper: Comparable {
             Text(title)
               .font(.system(size: 17, weight: .semibold))
           }
+          Text("UIView Preview not supported on iOS 17")
+            .foregroundStyle(Color.red)
+            .font(.caption.monospacedDigit())
           Text("\(fileID):\(line)")
             .font(.caption.monospacedDigit())
-          Text("UIView Preview not supported (UIKit.UIViewPreviewSource)")
+          BookSpacer(height: 16)
+        }
+      }
+
+    case "UIKit.UIViewControllerPreviewSource": // iOS 17
+      // Unsupported due to iOS 17 not supporting casting between non-sendable closure types
+      return {
+        VStack {
+          if let title, !title.isEmpty {
+            Text(title)
+              .font(.system(size: 17, weight: .semibold))
+          }
+          Text("UIViewController Preview not supported on iOS 17")
             .foregroundStyle(Color.red)
             .font(.caption.monospacedDigit())
+          Text("\(fileID):\(line)")
+            .font(.caption.monospacedDigit())
           BookSpacer(height: 16)
         }
       }
@@ -103,11 +123,11 @@ struct PreviewRegistryWrapper: Comparable {
             Text(title)
               .font(.system(size: 17, weight: .semibold))
           }
-          Text("\(fileID):\(line)")
-            .font(.caption.monospacedDigit())
           Text("Failed to load preview (\(sourceTypeName))")
             .foregroundStyle(Color.red)
             .font(.caption.monospacedDigit())
+          Text("\(fileID):\(line)")
+            .font(.caption.monospacedDigit())
           BookSpacer(height: 16)
         }
       }
@@ -152,7 +172,7 @@ struct PreviewRegistryWrapper: Comparable {
 
     subscript<T>(_ key: String, _ nextKeys: String...) -> T {
       if nextKeys.isEmpty {
-        return fields[key] as! T
+        return fields[key]! as! T
       }
       else {
         return Self.traverse(from: fields[key]!, nextKeys: nextKeys) as! T