From 589063f36bccc007569744e1ed700662321ffa14 Mon Sep 17 00:00:00 2001
From: Laura Hausmann <laura@hausmann.dev>
Date: Tue, 13 Feb 2024 02:02:42 +0100
Subject: [PATCH] [backend/drive] Calculate blurhash for images (ISH-54)

---
 .../Core/Services/DriveService.cs             | 22 +++++++++++++++++--
 Iceshrimp.Backend/Iceshrimp.Backend.csproj    |  1 +
 Iceshrimp.NET.sln.DotSettings                 |  1 +
 3 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/Iceshrimp.Backend/Core/Services/DriveService.cs b/Iceshrimp.Backend/Core/Services/DriveService.cs
index 1c4e7676..11c66e11 100644
--- a/Iceshrimp.Backend/Core/Services/DriveService.cs
+++ b/Iceshrimp.Backend/Core/Services/DriveService.cs
@@ -1,4 +1,5 @@
 using System.Diagnostics.CodeAnalysis;
+using Blurhash.ImageSharp;
 using Iceshrimp.Backend.Core.Configuration;
 using Iceshrimp.Backend.Core.Database;
 using Iceshrimp.Backend.Core.Database.Tables;
@@ -7,6 +8,8 @@ using Iceshrimp.Backend.Core.Middleware;
 using Iceshrimp.Backend.Core.Queues;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.Options;
+using SixLabors.ImageSharp;
+using SixLabors.ImageSharp.PixelFormats;
 
 namespace Iceshrimp.Backend.Core.Services;
 
@@ -94,6 +97,21 @@ public class DriveService(
 		}
 
 		buf.Seek(0, SeekOrigin.Begin);
+
+		string? blurhash = null;
+
+		if (request.MimeType.StartsWith("image/")) {
+			try {
+				var image = await Image.LoadAsync<Rgba32>(buf);
+				blurhash = Blurhasher.Encode(image, 7, 7);
+			}
+			catch {
+				logger.LogError("Failed to generate blurhash for image with mime type {type}", request.MimeType);
+			}
+			
+			buf.Seek(0, SeekOrigin.Begin);
+		}
+
 		var (filename, guid) = GenerateFilenameKeepingExtension(request.Filename);
 		var shouldStore    = storageConfig.Value.MediaRetention != null || user.Host == null;
 		var storedInternal = storageConfig.Value.Mode == Enums.FileStorage.Local;
@@ -138,8 +156,8 @@ public class DriveService(
 			Comment        = request.Comment,
 			Type           = request.MimeType,
 			RequestHeaders = request.RequestHeaders,
-			RequestIp      = request.RequestIp
-			//Blurhash           = TODO,
+			RequestIp      = request.RequestIp,
+			Blurhash       = blurhash,
 			//Properties         = TODO,
 			//ThumbnailUrl       = TODO,
 			//ThumbnailAccessKey = TODO,
diff --git a/Iceshrimp.Backend/Iceshrimp.Backend.csproj b/Iceshrimp.Backend/Iceshrimp.Backend.csproj
index c7603344..1dddfe66 100644
--- a/Iceshrimp.Backend/Iceshrimp.Backend.csproj
+++ b/Iceshrimp.Backend/Iceshrimp.Backend.csproj
@@ -18,6 +18,7 @@
         <PackageReference Include="Amazon.S3" Version="0.31.2"/>
         <PackageReference Include="AngleSharp" Version="1.1.0"/>
         <PackageReference Include="Asp.Versioning.Http" Version="8.0.0"/>
+        <PackageReference Include="Blurhash.ImageSharp" Version="3.0.0" />
         <PackageReference Include="cuid.net" Version="5.0.2"/>
         <PackageReference Include="dotNetRdf.Core" Version="3.2.1-dev"/>
         <PackageReference Include="EntityFrameworkCore.Exceptions.PostgreSQL" Version="8.0.0" />
diff --git a/Iceshrimp.NET.sln.DotSettings b/Iceshrimp.NET.sln.DotSettings
index 8967dc2b..8fb9faf5 100644
--- a/Iceshrimp.NET.sln.DotSettings
+++ b/Iceshrimp.NET.sln.DotSettings
@@ -344,6 +344,7 @@
 	<s:Boolean x:Key="/Default/Environment/SettingsMigration/IsMigratorApplied/=JetBrains_002EReSharper_002EPsi_002ECSharp_002ECodeStyle_002ECSharpPlaceEmbeddedOnSameLineMigration/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/Environment/SettingsMigration/IsMigratorApplied/=JetBrains_002EReSharper_002EPsi_002ECSharp_002ECodeStyle_002ECSharpUseContinuousIndentInsideBracesMigration/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/Environment/SettingsMigration/IsMigratorApplied/=JetBrains_002EReSharper_002EPsi_002ECSharp_002ECodeStyle_002ESettingsUpgrade_002EMigrateBlankLinesAroundFieldToBlankLinesAroundProperty/@EntryIndexedValue">True</s:Boolean>
+	<s:Boolean x:Key="/Default/UserDictionary/Words/=blurhash/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=Iceshrimp/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=Identicon/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=litepub/@EntryIndexedValue">True</s:Boolean>