From a5ad8e43b16876b565c63e08689b8259d9adb1af Mon Sep 17 00:00:00 2001
From: Shadowfacts <me@shadowfacts.net>
Date: Tue, 15 Nov 2022 21:45:42 -0500
Subject: [PATCH] Disable attachment colorspace conversion on Mastodon v4

---
 Tusker/API/InstanceFeatures.swift                 |  8 ++++++++
 Tusker/API/PostService.swift                      |  2 +-
 Tusker/Models/CompositionAttachmentData.swift     | 15 ++++++++++-----
 Tusker/Screens/Compose/ComposeAttachmentRow.swift |  3 ++-
 4 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/Tusker/API/InstanceFeatures.swift b/Tusker/API/InstanceFeatures.swift
index 95c10a09..39f5ee4d 100644
--- a/Tusker/API/InstanceFeatures.swift
+++ b/Tusker/API/InstanceFeatures.swift
@@ -76,6 +76,14 @@ struct InstanceFeatures {
         }
     }
     
+    var needsWideColorGamutHack: Bool {
+        if case .mastodon(_, .some(let version)) = instanceType {
+            return version < Version(4, 0, 0)
+        } else {
+            return true
+        }
+    }
+    
     mutating func update(instance: Instance, nodeInfo: NodeInfo?) {
         let ver = instance.version.lowercased()
         if ver.contains("glitch") {
diff --git a/Tusker/API/PostService.swift b/Tusker/API/PostService.swift
index 5628327c..91a689aa 100644
--- a/Tusker/API/PostService.swift
+++ b/Tusker/API/PostService.swift
@@ -87,7 +87,7 @@ class PostService: ObservableObject {
     
     private func getData(for attachment: CompositionAttachment) async throws -> (Data, UTType) {
         return try await withCheckedThrowingContinuation { continuation in
-            attachment.data.getData { result in
+            attachment.data.getData(features: mastodonController.instanceFeatures) { result in
                 switch result {
                 case let .success(res):
                     continuation.resume(returning: res)
diff --git a/Tusker/Models/CompositionAttachmentData.swift b/Tusker/Models/CompositionAttachmentData.swift
index 6b6c0222..10fec3d8 100644
--- a/Tusker/Models/CompositionAttachmentData.swift
+++ b/Tusker/Models/CompositionAttachmentData.swift
@@ -51,7 +51,7 @@ enum CompositionAttachmentData {
         }
     }
     
-    func getData(completion: @escaping (Result<(Data, UTType), Error>) -> Void) {
+    func getData(features: InstanceFeatures, skipAllConversion: Bool = false, completion: @escaping (Result<(Data, UTType), Error>) -> Void) {
         switch self {
         case let .image(image):
             // Export as JPEG instead of PNG, otherweise photos straight from the camera are too large
@@ -71,21 +71,26 @@ enum CompositionAttachmentData {
                         return
                     }
                     
+                    guard !skipAllConversion else {
+                        completion(.success((data, UTType(dataUTI)!)))
+                        return
+                    }
+                    
                     let utType: UTType
                     let image = CIImage(data: data)!
-                    let needsColorSpaceConversion = image.colorSpace?.name != CGColorSpace.sRGB
+                    let needsColorSpaceConversion = features.needsWideColorGamutHack && image.colorSpace?.name != CGColorSpace.sRGB
     
                     // neither Mastodon nor Pleroma handles HEIC well, so convert to JPEG
                     // they also do a bad job converting wide color gamut images (they seem to just drop the profile, letting the wide-gamut values be reinterprete as sRGB)
                     // if that changes in the future, we'll need to pass the InstanceFeatures in here somehow and gate the conversion
                     if needsColorSpaceConversion || dataUTI == "public.heic" {
                         let context = CIContext()
-                        let sRGB = CGColorSpace(name: CGColorSpace.sRGB)!
+                        let colorSpace = needsColorSpaceConversion || image.colorSpace != nil ? CGColorSpace(name: CGColorSpace.sRGB)! : image.colorSpace!
                         if dataUTI == "public.png" {
-                            data = context.pngRepresentation(of: image, format: .ARGB8, colorSpace: sRGB)!
+                            data = context.pngRepresentation(of: image, format: .ARGB8, colorSpace: colorSpace)!
                             utType = .png
                         } else {
-                            data = context.jpegRepresentation(of: image, colorSpace: sRGB)!
+                            data = context.jpegRepresentation(of: image, colorSpace: colorSpace)!
                             utType = .jpeg
                         }
                     } else {
diff --git a/Tusker/Screens/Compose/ComposeAttachmentRow.swift b/Tusker/Screens/Compose/ComposeAttachmentRow.swift
index b08e971c..ab26294c 100644
--- a/Tusker/Screens/Compose/ComposeAttachmentRow.swift
+++ b/Tusker/Screens/Compose/ComposeAttachmentRow.swift
@@ -15,6 +15,7 @@ struct ComposeAttachmentRow: View {
     @ObservedObject var draft: Draft
     @ObservedObject var attachment: CompositionAttachment
     
+    @EnvironmentObject var mastodonController: MastodonController
     @EnvironmentObject var uiState: ComposeUIState
     @State private var mode: Mode = .allowEntry
     @State private var isShowingTextRecognitionFailedAlert = false
@@ -90,7 +91,7 @@ struct ComposeAttachmentRow: View {
         mode = .recognizingText
         
         DispatchQueue.global(qos: .userInitiated).async {
-            self.attachment.data.getData { (result) in
+            self.attachment.data.getData(features: mastodonController.instanceFeatures, skipAllConversion: true) { (result) in
                 let data: Data
                 do {
                     try data = result.get().0