From 03ee03b8761a4690dbf3146b089787fb6eb665f4 Mon Sep 17 00:00:00 2001
From: Matt Bruce <mbrucedogs@gmail.com>
Date: Mon, 22 Dec 2025 12:20:04 -0600
Subject: [PATCH] Signed-off-by: Matt Bruce <mbrucedogs@gmail.com>

---
 Blackjack/Agents.md                          | 60 +++++++++++++++++++-
 Blackjack/Engine/GameState.swift             | 15 +++++
 Blackjack/Views/Game/ActionButtonsView.swift | 14 +----
 3 files changed, 76 insertions(+), 13 deletions(-)

diff --git a/Blackjack/Agents.md b/Blackjack/Agents.md
index f4bf715..4bc821c 100644
--- a/Blackjack/Agents.md
+++ b/Blackjack/Agents.md
@@ -49,8 +49,66 @@ You are a **Senior iOS Engineer**, specializing in SwiftUI, SwiftData, and relat
 - Do not use `GeometryReader` if a newer alternative would work as well, such as `containerRelativeFrame()` or `visualEffect()`.
 - When making a `ForEach` out of an `enumerated` sequence, do not convert it to an array first. So, prefer `ForEach(x.enumerated(), id: \.element.id)` instead of `ForEach(Array(x.enumerated()), id: \.element.id)`.
 - When hiding scroll view indicators, use the `.scrollIndicators(.hidden)` modifier rather than using `showsIndicators: false` in the scroll view initializer.
-- Place view logic into view models or similar, so it can be tested.
 - Avoid `AnyView` unless it is absolutely required.
+
+
+## View/State separation (MVVM-lite)
+
+**Views should be "dumb" renderers.** All business logic belongs in `GameState` or dedicated view models.
+
+### What belongs in the State/ViewModel:
+- **Business logic**: Calculations, validations, game rules
+- **Computed properties based on game data**: hints, recommendations, derived values
+- **State checks**: `isPlayerTurn`, `canHit`, `isGameOver`, `isBetBelowMinimum`
+- **Data transformations**: statistics calculations, filtering, aggregations
+
+### What is acceptable in Views:
+- **Pure UI layout logic**: `isIPad`, `maxContentWidth` based on size class
+- **Visual styling**: color selection based on state (`valueColor`, `resultColor`)
+- **@ViewBuilder sub-views**: breaking up complex layouts
+- **Accessibility labels**: combining data into accessible descriptions
+
+### Examples
+
+**❌ BAD - Business logic in view:**
+```swift
+struct MyView: View {
+    @Bindable var state: GameState
+    
+    private var isBetBelowMinimum: Bool {
+        state.currentBet > 0 && state.currentBet < state.settings.minBet
+    }
+    
+    private var currentHint: String? {
+        guard let hand = state.activeHand else { return nil }
+        return state.engine.getHint(playerHand: hand, dealerUpCard: upCard)
+    }
+}
+```
+
+**✅ GOOD - Logic in GameState, view just reads:**
+```swift
+// In GameState:
+var isBetBelowMinimum: Bool {
+    currentBet > 0 && currentBet < settings.minBet
+}
+
+var currentHint: String? {
+    guard settings.showHints, isPlayerTurn else { return nil }
+    guard let hand = activeHand, let upCard = dealerUpCard else { return nil }
+    return engine.getHint(playerHand: hand, dealerUpCard: upCard)
+}
+
+// In View:
+if state.isBetBelowMinimum { ... }
+if let hint = state.currentHint { HintView(hint: hint) }
+```
+
+### Benefits:
+- **Testable**: GameState logic can be unit tested without UI
+- **Single source of truth**: No duplicated logic across views
+- **Cleaner views**: Views focus purely on layout and presentation
+- **Easier debugging**: Logic is centralized, not scattered
 - **Never use raw numeric literals** for padding, spacing, opacity, font sizes, dimensions, corner radii, shadows, or animation durations—always use Design constants (see "No magic numbers" section).
 - **Never use inline `Color(red:green:blue:)` or hex colors**—define all colors in the `Color` extension in `DesignConstants.swift` with semantic names.
 - Avoid using UIKit colors in SwiftUI code.
diff --git a/Blackjack/Engine/GameState.swift b/Blackjack/Engine/GameState.swift
index c6341cb..f485c38 100644
--- a/Blackjack/Engine/GameState.swift
+++ b/Blackjack/Engine/GameState.swift
@@ -185,6 +185,21 @@ final class GameState {
         return engine.getHint(playerHand: hand, dealerUpCard: upCard)
     }
     
+    /// Whether the current bet is below the minimum required.
+    var isBetBelowMinimum: Bool {
+        currentBet > 0 && currentBet < settings.minBet
+    }
+    
+    /// Amount needed to reach minimum bet.
+    var amountNeededForMinimum: Int {
+        max(0, settings.minBet - currentBet)
+    }
+    
+    /// Whether the current bet has reached the maximum.
+    var isBetAtMaximum: Bool {
+        currentBet >= settings.maxBet
+    }
+    
     /// Betting recommendation based on the true count.
     var bettingHint: String? {
         guard settings.showCardCount else { return nil }
diff --git a/Blackjack/Views/Game/ActionButtonsView.swift b/Blackjack/Views/Game/ActionButtonsView.swift
index 6fdcb1c..759055a 100644
--- a/Blackjack/Views/Game/ActionButtonsView.swift
+++ b/Blackjack/Views/Game/ActionButtonsView.swift
@@ -43,23 +43,13 @@ struct ActionButtonsView: View {
     
     // MARK: - Betting Phase Buttons
     
-    /// Whether the current bet meets the minimum requirement
-    private var isBetBelowMinimum: Bool {
-        state.currentBet > 0 && state.currentBet < state.settings.minBet
-    }
-    
-    /// Amount needed to reach minimum bet
-    private var amountNeededForMinimum: Int {
-        state.settings.minBet - state.currentBet
-    }
-    
     @ViewBuilder
     private var bettingButtons: some View {
         if state.currentBet > 0 {
             VStack(spacing: Design.Spacing.small) {
                 // Show hint if bet is below minimum
-                if isBetBelowMinimum {
-                    Text(String(localized: "Add $\(amountNeededForMinimum) more to meet minimum"))
+                if state.isBetBelowMinimum {
+                    Text(String(localized: "Add $\(state.amountNeededForMinimum) more to meet minimum"))
                         .font(.system(size: Design.BaseFontSize.small, weight: .medium))
                         .foregroundStyle(.orange)
                         .transition(.opacity)