V12: Update ImageSharp V3 and Add Legacy V2 Project (#14216)

* Rename old imagesharp to v2

* Add Ronalds PR as imagesharp

* Ensure that we use V3 by default

src/Umbraco.Cms.Imaging.ImageSharp.V2/ConfigureImageSharpMiddlewareOptions.cs

@@ -0,0 +1,87 @@
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Http.Headers;
+using Microsoft.Extensions.Options;
+using Microsoft.Net.Http.Headers;
+using SixLabors.ImageSharp;
+using SixLabors.ImageSharp.Web.Commands;
+using SixLabors.ImageSharp.Web.Middleware;
+using SixLabors.ImageSharp.Web.Processors;
+using Umbraco.Cms.Core.Configuration.Models;
+
+namespace Umbraco.Cms.Imaging.ImageSharp.V2;
+
+/// <summary>
+///     Configures the ImageSharp middleware options.
+/// </summary>
+/// <seealso cref="IConfigureOptions{ImageSharpMiddlewareOptions}" />
+public sealed class ConfigureImageSharpMiddlewareOptions : IConfigureOptions<ImageSharpMiddlewareOptions>
+{
+    private readonly Configuration _configuration;
+    private readonly ImagingSettings _imagingSettings;
+
+    /// <summary>
+    ///     Initializes a new instance of the <see cref="ConfigureImageSharpMiddlewareOptions" /> class.
+    /// </summary>
+    /// <param name="configuration">The ImageSharp configuration.</param>
+    /// <param name="imagingSettings">The Umbraco imaging settings.</param>
+    public ConfigureImageSharpMiddlewareOptions(Configuration configuration, IOptions<ImagingSettings> imagingSettings)
+    {
+        _configuration = configuration;
+        _imagingSettings = imagingSettings.Value;
+    }
+
+    /// <inheritdoc />
+    public void Configure(ImageSharpMiddlewareOptions options)
+    {
+        options.Configuration = _configuration;
+
+        options.BrowserMaxAge = _imagingSettings.Cache.BrowserMaxAge;
+        options.CacheMaxAge = _imagingSettings.Cache.CacheMaxAge;
+        options.CacheHashLength = _imagingSettings.Cache.CacheHashLength;
+
+        // Use configurable maximum width and height
+        options.OnParseCommandsAsync = context =>
+        {
+            if (context.Commands.Count == 0)
+            {
+                return Task.CompletedTask;
+            }
+
+            var width = context.Parser.ParseValue<int>(
+                context.Commands.GetValueOrDefault(ResizeWebProcessor.Width),
+                context.Culture);
+            if (width <= 0 || width > _imagingSettings.Resize.MaxWidth)
+            {
+                context.Commands.Remove(ResizeWebProcessor.Width);
+            }
+
+            var height = context.Parser.ParseValue<int>(
+                context.Commands.GetValueOrDefault(ResizeWebProcessor.Height),
+                context.Culture);
+            if (height <= 0 || height > _imagingSettings.Resize.MaxHeight)
+            {
+                context.Commands.Remove(ResizeWebProcessor.Height);
+            }
+
+            return Task.CompletedTask;
+        };
+
+        // Change Cache-Control header when cache buster value is present
+        options.OnPrepareResponseAsync = context =>
+        {
+            if (context.Request.Query.ContainsKey("rnd") || context.Request.Query.ContainsKey("v"))
+            {
+                ResponseHeaders headers = context.Response.GetTypedHeaders();
+
+                CacheControlHeaderValue cacheControl =
+                    headers.CacheControl ?? new CacheControlHeaderValue { Public = true };
+                cacheControl.MustRevalidate = false; // ImageSharp enables this by default
+                cacheControl.Extensions.Add(new NameValueHeaderValue("immutable"));
+
+                headers.CacheControl = cacheControl;
+            }
+
+            return Task.CompletedTask;
+        };
+    }
+}