implement download feature

DynamicIsland/components/Downloads/DownloadLiveActivity.swift

@@ -0,0 +1,103 @@
+//
+//  DownloadLiveActivity.swift
+//  DynamicIsland
+//
+//  Shows a download indicator when Chromium-style downloads
+//  are detected in the user's Downloads folder.
+//
+
+import SwiftUI
+import Defaults
+
+struct DownloadLiveActivity: View {
+    @EnvironmentObject var vm: DynamicIslandViewModel
+    @ObservedObject var downloadManager = DownloadManager.shared
+    
+    @State private var isHovering: Bool = false
+    @State private var gestureProgress: CGFloat = 0
+    @State private var isExpanded: Bool = false
+    
+    private var tint: Color {
+        .accentColor
+    }
+    
+    var body: some View {
+        HStack(spacing: 0) {
+            // Left side: download icon capsule
+            Color.clear
+                .background {
+                    if isExpanded {
+                        HStack {
+                            ZStack {
+                                RoundedRectangle(cornerRadius: 6, style: .continuous)
+                                    .fill(tint.opacity(0.14))
+                                
+                                Image(systemName: "arrow.down.circle.fill")
+                                    .font(.system(size: 14, weight: .semibold))
+                                    .foregroundStyle(tint)
+                            }
+                            .frame(
+                                width: vm.effectiveClosedNotchHeight - 12,
+                                height: vm.effectiveClosedNotchHeight - 12
+                            )
+                        }
+                        .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .leading)
+                    }
+                }
+                .frame(
+                    width: isExpanded ? max(0, vm.effectiveClosedNotchHeight - (isHovering ? 0 : 12) + gestureProgress / 2) : 0,
+                    height: vm.effectiveClosedNotchHeight - (isHovering ? 0 : 12)
+                )
+            
+            // Center: closed notch body (slightly wider during downloads)
+            Rectangle()
+                .fill(.black)
+                .frame(
+                    width: vm.closedNotchSize.width
+                        + (isHovering ? 8 : 0)
+                        + (downloadManager.isDownloading ? 40 : 0)
+                )
+            
+            // Right side: indeterminate-style progress bar
+            Color.clear
+                .background {
+                    if isExpanded {
+                        HStack {
+                            if downloadManager.isDownloadCompleted {
+                                Image(systemName: "checkmark.circle.fill")
+                                    .foregroundStyle(.green)
+                                    .font(.system(size: 16, weight: .semibold))
+                                    .padding(.trailing, 6)
+                            } else if Defaults[.selectedDownloadIndicatorStyle] == .circle {
+                                SpinningCircleDownloadView()
+                                    .padding(.trailing, 6)
+                            } else {
+                                ProgressView()
+                                    .progressViewStyle(.linear)
+                                    .tint(.accentColor)
+                                    .frame(width: 40)
+                            }
+                        }
+                        .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .trailing)
+                    }
+                }
+                .frame(
+                    width: isExpanded ? max(60, vm.effectiveClosedNotchHeight) : 0,
+                    height: vm.effectiveClosedNotchHeight - (isHovering ? 0 : 12)
+                )
+        }
+        .frame(height: vm.effectiveClosedNotchHeight + (isHovering ? 8 : 0))
+        .onAppear {
+            withAnimation(.smooth(duration: 0.35)) {
+                isExpanded = true
+            }
+        }
+        .onChange(of: downloadManager.isDownloading) { _, newValue in
+            withAnimation(.smooth(duration: 0.35)) {
+                isExpanded = newValue
+            }
+        }
+    }
+}
+
+

DynamicIsland/components/Downloads/SpinningCircleDownloadView.swift

@@ -0,0 +1,28 @@
+import SwiftUI
+
+struct SpinningCircleDownloadView: View {
+    @State private var isRotating = false
+    
+    var body: some View {
+        ZStack {
+            // Gray track
+            Circle()
+                .stroke(Color.gray.opacity(0.3), lineWidth: 3.5)
+            
+            // Blue spinning segment
+            Circle()
+                .trim(from: 0, to: 0.25)
+                .stroke(
+                    Color.accentColor,
+                    style: StrokeStyle(lineWidth: 3.5, lineCap: .round)
+                )
+                .rotationEffect(Angle(degrees: isRotating ? 360 : 0))
+                .onAppear {
+                    withAnimation(.linear(duration: 1).repeatForever(autoreverses: false)) {
+                        isRotating = true
+                    }
+                }
+        }
+        .frame(width: 16, height: 16)
+    }
+}