From ebe624605bc00292d324f75910df561e1a40f11c Mon Sep 17 00:00:00 2001
From: Justin Mazzocchi <2831158+jzzocc@users.noreply.github.com>
Date: Sun, 3 Jan 2021 14:37:06 -0800
Subject: [PATCH] wip

---
 View Controllers/NewStatusViewController.swift      | 12 +++++++++++-
 .../Sources/ViewModels/CompositionViewModel.swift   | 13 ++++++++++++-
 Views/CompositionInputAccessoryView.swift           | 11 +++++++++--
 3 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/View Controllers/NewStatusViewController.swift b/View Controllers/NewStatusViewController.swift
index 19424ca..b968957 100644
--- a/View Controllers/NewStatusViewController.swift	
+++ b/View Controllers/NewStatusViewController.swift	
@@ -212,6 +212,10 @@ private extension NewStatusViewController {
 
         configuration.preferredAssetRepresentationMode = .current
 
+        if !compositionViewModel.canAddNonImageAttachment {
+            configuration.filter = .images
+        }
+
         let picker = PHPickerViewController(configuration: configuration)
 
         picker.modalPresentationStyle = .overFullScreen
@@ -259,9 +263,15 @@ private extension NewStatusViewController {
 
         picker.sourceType = .camera
         picker.allowsEditing = true
-        picker.mediaTypes = [UTType.image.description, UTType.movie.description]
         picker.modalPresentationStyle = .overFullScreen
         picker.delegate = self
+
+        if compositionViewModel.canAddNonImageAttachment {
+            picker.mediaTypes = [UTType.image.description, UTType.movie.description]
+        } else {
+            picker.mediaTypes = [UTType.image.description]
+        }
+
         present(picker, animated: true)
     }
     #endif
diff --git a/ViewModels/Sources/ViewModels/CompositionViewModel.swift b/ViewModels/Sources/ViewModels/CompositionViewModel.swift
index 6944e7e..474b291 100644
--- a/ViewModels/Sources/ViewModels/CompositionViewModel.swift
+++ b/ViewModels/Sources/ViewModels/CompositionViewModel.swift
@@ -12,8 +12,10 @@ public final class CompositionViewModel: ObservableObject, Identifiable {
     @Published public var contentWarning = ""
     @Published public var displayContentWarning = false
     @Published public private(set) var attachmentViewModels = [CompositionAttachmentViewModel]()
-    @Published public private(set) var isPostable = false
     @Published public private(set) var attachmentUpload: AttachmentUpload?
+    @Published public private(set) var isPostable = false
+    @Published public private(set) var canAddAttachment = true
+    @Published public private(set) var canAddNonImageAttachment = true
 
     private var cancellables = Set<AnyCancellable>()
 
@@ -25,6 +27,11 @@ public final class CompositionViewModel: ObservableObject, Identifiable {
                 textPresent || attachmentPresent
             }
             .assign(to: &$isPostable)
+        $attachmentViewModels
+            .combineLatest($attachmentUpload)
+            .map { $0.count < Self.maxAttachmentCount && $1 == nil }
+            .assign(to: &$canAddAttachment)
+        $attachmentViewModels.map(\.isEmpty).assign(to: &$canAddNonImageAttachment)
     }
 }
 
@@ -75,3 +82,7 @@ extension CompositionViewModel {
             .eraseToAnyPublisher()
     }
 }
+
+private extension CompositionViewModel {
+    static let maxAttachmentCount = 4
+}
diff --git a/Views/CompositionInputAccessoryView.swift b/Views/CompositionInputAccessoryView.swift
index 971fb41..ed66a92 100644
--- a/Views/CompositionInputAccessoryView.swift
+++ b/Views/CompositionInputAccessoryView.swift
@@ -60,10 +60,10 @@ private extension CompositionInputAccessoryView {
         },
         for: .touchUpInside)
 
+        let cameraButton = UIButton()
+
         #if !IS_SHARE_EXTENSION
         if AVCaptureDevice.authorizationStatus(for: .video) != .restricted {
-            let cameraButton = UIButton()
-
             stackView.addArrangedSubview(cameraButton)
             cameraButton.setImage(
                 UIImage(
@@ -121,6 +121,13 @@ private extension CompositionInputAccessoryView {
             self.parentViewModel.insert(after: self.viewModel)
         }, for: .touchUpInside)
 
+        viewModel.$canAddAttachment
+            .sink {
+                mediaButton.isEnabled = $0
+                cameraButton.isEnabled = $0
+            }
+            .store(in: &cancellables)
+
         viewModel.$isPostable
             .sink { [weak self] in self?.addButton.isEnabled = $0 }
             .store(in: &cancellables)