Allow to record a voice message (#1926)

ElementX/Sources/Other/VoiceMessage/EstimatedWaveformView.swift

@@ -0,0 +1,132 @@
+//
+// Copyright 2023 New Vector Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+import SwiftUI
+
+struct EstimatedWaveform: Equatable, Hashable {
+    static let dataRange: ClosedRange<UInt16> = 0...1024
+    let data: [UInt16]
+}
+
+extension EstimatedWaveform {
+    /// Maps the `data` array to Float values in the range 0...1 respecting the `Self.dataRange` limits.
+    /// Up to `maxSamplesCount` will be returned in the output array
+    func normalisedData(maxSamplesCount: Int) -> [Float] {
+        guard maxSamplesCount > 0 else {
+            return []
+        }
+
+        // Filter the data to keep only the expected number of samples
+        let result: [UInt16]
+        if data.count > maxSamplesCount {
+            result = (0..<maxSamplesCount)
+                .map { index in
+                    let targetIndex = Int((Double(index) * (Double(data.count) / Double(maxSamplesCount))).rounded())
+                    return UInt16(data[targetIndex])
+                }
+        } else {
+            result = data
+        }
+
+        // Normalize the sample in the allowed range
+        return result.map { Float($0) / Float(Self.dataRange.upperBound) }
+    }
+}
+
+extension EstimatedWaveform {
+    static let mockWaveform = EstimatedWaveform(data: [0, 0, 0, 3, 3, 127, 400, 266, 126, 122, 373, 251, 45, 112,
+                                                       334, 205, 99, 138, 397, 354, 125, 361, 199, 51,
+                                                       294, 131, 19, 2, 3, 3, 1, 2, 0, 0,
+                                                       0, 0])
+}
+
+struct EstimatedWaveformView: View {
+    var lineWidth: CGFloat = 2
+    var linePadding: CGFloat = 2
+    var waveform: EstimatedWaveform
+    private let minimumGraphAmplitude: CGFloat = 1
+    var progress: CGFloat = 0.0
+    
+    @State private var normalizedWaveformData: [Float] = []
+    
+    var body: some View {
+        GeometryReader { geometry in
+            WaveformShape(lineWidth: lineWidth,
+                          linePadding: linePadding,
+                          waveformData: normalizedWaveformData)
+                .stroke(Color.compound.iconSecondary, style: StrokeStyle(lineWidth: lineWidth, lineCap: .round))
+                .progressMask(progress: progress)
+                .preference(key: ViewSizeKey.self, value: geometry.size)
+        }
+        .onPreferenceChange(ViewSizeKey.self) { size in
+            buildNormalizedWaveformData(size: size)
+        }
+    }
+    
+    private func buildNormalizedWaveformData(size: CGSize) {
+        let count = Int(size.width / (lineWidth + linePadding))
+        // Rebuild the normalized waveform data only if the count has changed
+        if normalizedWaveformData.count == count {
+            return
+        }
+        normalizedWaveformData = waveform.normalisedData(maxSamplesCount: count)
+    }
+}
+
+private struct ViewSizeKey: PreferenceKey {
+    static var defaultValue: CGSize = .zero
+    static func reduce(value: inout CGSize, nextValue: () -> CGSize) {
+        value = nextValue()
+    }
+}
+
+private struct WaveformShape: Shape {
+    let lineWidth: CGFloat
+    let linePadding: CGFloat
+    let waveformData: [Float]
+    var minimumGraphAmplitude: CGFloat = 1.0
+    
+    func path(in rect: CGRect) -> Path {
+        let width = rect.size.width
+        let height = rect.size.height
+        let centerY = rect.size.height / 2
+        var xOffset: CGFloat = lineWidth / 2
+        var index = 0
+        
+        var path = Path()
+        while xOffset <= width {
+            let sample = CGFloat(index >= waveformData.count ? 0 : waveformData[index])
+            let drawingAmplitude = max(minimumGraphAmplitude, sample * (height - 2))
+            
+            path.move(to: CGPoint(x: xOffset, y: centerY - drawingAmplitude / 2))
+            path.addLine(to: CGPoint(x: xOffset, y: centerY + drawingAmplitude / 2))
+            xOffset += lineWidth + linePadding
+            index += 1
+        }
+        
+        return path
+    }
+}
+
+struct EstimatedWaveformView_Previews: PreviewProvider, TestablePreview {
+    static var previews: some View {
+        // Wrap the WaveformView in a VStack otherwise the preview test will fail (because of Prefire / GeometryReader)
+        VStack {
+            EstimatedWaveformView(waveform: EstimatedWaveform.mockWaveform, progress: 0.5)
+                .frame(width: 140, height: 50)
+        }
+    }
+}

ElementX/Sources/Other/VoiceMessage/ProgressMaskModifier.swift

@@ -0,0 +1,56 @@
+//
+// Copyright 2023 New Vector Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+import SwiftUI
+
+extension View {
+    func progressMask(progress: CGFloat,
+                      trackColor: Color = .compound.iconSecondary,
+                      backgroundTrackColor: Color = .compound.iconQuaternary) -> some View {
+        modifier(ProgressMaskModifier(progress: progress,
+                                      trackColor: trackColor,
+                                      backgroundTrackColor: backgroundTrackColor))
+    }
+}
+
+private struct ProgressMaskModifier: ViewModifier {
+    private let progress: CGFloat
+    private let trackColor: Color
+    private let backgroundTrackColor: Color
+
+    init(progress: CGFloat, trackColor: Color, backgroundTrackColor: Color) {
+        self.progress = progress
+        self.trackColor = trackColor
+        self.backgroundTrackColor = backgroundTrackColor
+    }
+
+    func body(content: Content) -> some View {
+        GeometryReader { geometry in
+            ZStack(alignment: .leading) {
+                Rectangle()
+                    .fill(backgroundTrackColor)
+                    .frame(width: geometry.size.width, height: geometry.size.height)
+                
+                Rectangle()
+                    .fill(trackColor)
+                    .frame(width: max(0.0, geometry.size.width * progress), height: geometry.size.height)
+            }
+            .mask {
+                content
+            }
+        }
+    }
+}

ElementX/Sources/Other/VoiceMessage/WaveformSource.swift

@@ -0,0 +1,24 @@
+//
+// Copyright 2023 New Vector Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+import Foundation
+
+enum WaveformSource: Equatable {
+    /// File URL of the source audio file
+    case url(URL)
+    /// Array of small number of pre-computed samples
+    case data([Float])
+}

ElementX/Sources/Other/VoiceMessage/WaveformViewDragGestureModifier.swift

@@ -0,0 +1,98 @@
+//
+// Copyright 2023 New Vector Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+import DSWaveformImageViews
+import Foundation
+import SwiftUI
+
+struct WaveformViewDragGestureModifier: ViewModifier {
+    @GestureState private var dragGestureState = WaveformViewDragState.inactive
+    @Binding var dragState: WaveformViewDragState
+    
+    let minimumDragDistance: Double
+    
+    func body(content: Content) -> some View {
+        GeometryReader { geometry in
+            content
+                .gesture(SpatialTapGesture()
+                    .simultaneously(with: LongPressGesture())
+                    .sequenced(before: DragGesture(minimumDistance: minimumDragDistance, coordinateSpace: .local))
+                    .updating($dragGestureState) { value, state, _ in
+                        switch value {
+                        // (SpatialTap, LongPress) begins.
+                        case .first(let spatialLongPress):
+                            // Compute the progress with the spatialTap location
+                            let progress = (spatialLongPress.first?.location ?? .zero).x / geometry.size.width
+                            state = .pressing(progress: progress)
+                        // Long press confirmed, dragging may begin.
+                        case .second(let spatialLongPress, let drag) where spatialLongPress.second ?? false:
+                            var progress: Double = dragState.progress
+                            // Compute the progress with drag location
+                            if let location = drag?.location {
+                                progress = location.x / geometry.size.width
+                            }
+                            state = .dragging(progress: progress)
+                        // Dragging ended or the long press cancelled.
+                        default:
+                            state = .inactive
+                        }
+                    })
+        }
+        .onChange(of: dragGestureState) { value in
+            dragState = value
+        }
+    }
+}
+
+extension View {
+    func waveformDragGesture(_ dragState: Binding<WaveformViewDragState>, minimumDragDistance: Double = 0) -> some View {
+        modifier(WaveformViewDragGestureModifier(dragState: dragState,
+                                                 minimumDragDistance: minimumDragDistance))
+    }
+}
+
+enum WaveformViewDragState: Equatable {
+    case inactive
+    case pressing(progress: Double)
+    case dragging(progress: Double)
+    
+    var progress: Double {
+        switch self {
+        case .inactive:
+            return .zero
+        case .pressing(let progress), .dragging(let progress):
+            return progress
+        }
+    }
+    
+    var isActive: Bool {
+        switch self {
+        case .inactive:
+            return false
+        case .pressing, .dragging:
+            return true
+        }
+    }
+    
+    var isDragging: Bool {
+        switch self {
+        case .inactive, .pressing:
+            return false
+        case .dragging:
+            return true
+        }
+    }
+}