Tweak compose placeholders

Tusker/Screens/Compose/MainComposeTextView.swift

@@ -9,29 +9,9 @@
 import SwiftUI
 import Pachyderm
 
-struct MainComposeTextView: View {
+struct MainComposeTextView: View, PlaceholderViewProvider {
     @ObservedObject var draft: Draft
-    @State private var placeholder: Text = {
+    @State private var placeholder: PlaceholderView = Self.placeholderView()
-        let components = Calendar.current.dateComponents([.month, .day], from: Date())
-        if components.month == 3 && components.day == 14 {
-            if Date().formatted(date: .numeric, time: .omitted).starts(with: "3") {
-                return Text("Happy π day!")
-            }
-        } else if components.month == 9 && components.day == 5 {
-            // https://weirder.earth/@noracodes/109276419847254552
-            // https://retrocomputing.stackexchange.com/questions/14763/what-warning-was-given-on-attempting-to-post-to-usenet-circa-1990
-            return Text("This program posts news to thousands of machines throughout the entire populated world. Please be sure you know what you are doing.").italic()
-        } else if components.month == 9 && components.day == 21 {
-            return Text("Do you remember?")
-        } else if components.month == 10 && components.day == 31 {
-            if .random() {
-                return Text("Post something spooky!")
-            } else {
-                return Text("Any questions?")
-            }
-        }
-        return Text("What's on your mind?")
-    }()
     
     let minHeight: CGFloat = 150
     @State private var height: CGFloat?
@@ -68,6 +48,38 @@ struct MainComposeTextView: View {
             }
         }
     }
+    
+    @ViewBuilder
+    static func placeholderView() -> some View {
+        let components = Calendar.current.dateComponents([.month, .day], from: Date())
+        if components.month == 3 && components.day == 14,
+           Date().formatted(date: .numeric, time: .omitted).starts(with: "3") {
+            Text("Happy π day!")
+        } else if components.month == 4 && components.day == 1 {
+            Text("April Fool's!").rotationEffect(.radians(.pi), anchor: .center)
+        } else if components.month == 9 && components.day == 5 {
+            // https://weirder.earth/@noracodes/109276419847254552
+            // https://retrocomputing.stackexchange.com/questions/14763/what-warning-was-given-on-attempting-to-post-to-usenet-circa-1990
+            Text("This program posts news to thousands of machines throughout the entire populated world. Please be sure you know what you are doing.").italic()
+        } else if components.month == 9 && components.day == 21 {
+            Text("Do you remember?")
+        } else if components.month == 10 && components.day == 31 {
+            if .random() {
+                Text("Post something spooky!")
+            } else {
+                Text("Any questions?")
+            }
+        } else {
+            Text("What's on your mind?")
+        }
+    }
+}
+
+// exists to provide access to the type alias since the @State property needs it to be explicit
+private protocol PlaceholderViewProvider {
+    associatedtype PlaceholderView: View
+    @ViewBuilder
+    static func placeholderView() -> PlaceholderView
 }
 
 struct MainComposeWrappedTextView: UIViewRepresentable {