From e9a4c44d2252d3d67eda2eb82774095ab405aa63 Mon Sep 17 00:00:00 2001
From: Ruben <ruben@live.dk>
Date: Sat, 7 Sep 2024 17:00:51 +0200
Subject: [PATCH] Fix rotation when key is held down

---
 .../Views/ImageViewer.axaml.cs                | 37 ++++++++++++++-----
 .../ImageSizeCalculationHelper.cs             | 25 +++++++++++--
 2 files changed, 50 insertions(+), 12 deletions(-)

diff --git a/src/PicView.Avalonia/Views/ImageViewer.axaml.cs b/src/PicView.Avalonia/Views/ImageViewer.axaml.cs
index 8ead84f49..ed46a0d54 100644
--- a/src/PicView.Avalonia/Views/ImageViewer.axaml.cs
+++ b/src/PicView.Avalonia/Views/ImageViewer.axaml.cs
@@ -33,6 +33,8 @@ public partial class ImageViewer : UserControl
 
     public ImageViewer()
     {
+        // TODO: Make a zoom and pan custom control that will work for MVVM
+        
         InitializeComponent();
         AddHandler(PointerWheelChangedEvent, PreviewOnPointerWheelChanged, RoutingStrategies.Tunnel);
         AddHandler(Gestures.PointerTouchPadGestureMagnifyEvent, TouchMagnifyEvent, RoutingStrategies.Bubble);
@@ -443,21 +445,39 @@ public void Rotate(bool clockWise)
         {
             return;
         }
-        if (RotationHelper.IsValidRotation(vm.RotationAngle))
+
+        if (MainKeyboardShortcuts.IsKeyHeldDown)
         {
-            var nextAngle = RotationHelper.Rotate(vm.RotationAngle, clockWise);
-            vm.RotationAngle = nextAngle switch
+            vm.RotationAngle = clockWise ? vm.RotationAngle + 1 : vm.RotationAngle -1;
+            if (vm.RotationAngle < 0)
             {
-                360 => 0,
-                -90 => 270,
-                _ => nextAngle
-            };
+                vm.RotationAngle = 359;
+            }
+
+            if (vm.RotationAngle > 359)
+            {
+                vm.RotationAngle = 0;
+            }
         }
         else
         {
-            vm.RotationAngle = RotationHelper.NextRotationAngle(vm.RotationAngle, true);
+            if (RotationHelper.IsValidRotation(vm.RotationAngle))
+            {
+                var nextAngle = RotationHelper.Rotate(vm.RotationAngle, clockWise);
+                vm.RotationAngle = nextAngle switch
+                {
+                    360 => 0,
+                    -90 => 270,
+                    _ => nextAngle
+                };
+            }
+            else
+            {
+                vm.RotationAngle = RotationHelper.NextRotationAngle(vm.RotationAngle, true);
+            }
         }
 
+
         var rotateTransform = new RotateTransform(vm.RotationAngle);
 
         if (Dispatcher.UIThread.CheckAccess())
@@ -473,7 +493,6 @@ public void Rotate(bool clockWise)
         }
 
         WindowHelper.SetSize(vm);
-        MainImage.InvalidateVisual();
     }
     
     public void Rotate(double angle)
diff --git a/src/PicView.Core/Calculations/ImageSizeCalculationHelper.cs b/src/PicView.Core/Calculations/ImageSizeCalculationHelper.cs
index 5832f91f9..79a6e49cc 100644
--- a/src/PicView.Core/Calculations/ImageSizeCalculationHelper.cs
+++ b/src/PicView.Core/Calculations/ImageSizeCalculationHelper.cs
@@ -5,8 +5,12 @@ namespace PicView.Core.Calculations
 {
     public static class ImageSizeCalculationHelper
     {
+        /// <summary>
+        ///  Returns the interface size of the titlebar based on OS
+        /// </summary>
         public static double GetInterfaceSize()
         {
+            // TODO: find a more elegant solution
             return RuntimeInformation.IsOSPlatform(OSPlatform.OSX) ? 165 : 228;
         }
 
@@ -271,9 +275,24 @@ public static double GetTitleMaxWidth(double rotationAngle, double width, double
 
             if (SettingsHelper.Settings.WindowProperties.AutoFit && !maximized)
             {
-                titleMaxWidth = rotationAngle is 0 or 180
-                    ? Math.Max(width, monitorMinWidth)
-                    : Math.Max(height, monitorMinHeight);
+                switch (rotationAngle)
+                {
+                    case 0 or 180:
+                        titleMaxWidth = Math.Max(width, monitorMinWidth);
+                        break;
+                    case 90 or 270:
+                        titleMaxWidth = Math.Max(height, monitorMinHeight);
+                        break;
+                    default:
+                    {
+                        var rotationRadians = rotationAngle * Math.PI / 180;
+                        var newWidth = Math.Abs(width * Math.Cos(rotationRadians)) +
+                                       Math.Abs(height * Math.Sin(rotationRadians));
+
+                        titleMaxWidth = Math.Max(newWidth, monitorMinWidth);
+                        break;
+                    }
+                }
 
                 titleMaxWidth = titleMaxWidth - interfaceSize < interfaceSize
                     ? interfaceSize