auto sync rime dir to app group

Author: eagleoflqj

src/CMakeLists.txt

@@ -3,6 +3,7 @@ add_executable(
     MACOSX_BUNDLE
     ContentView.swift
     App.swift
+    util.swift
 )
 
 add_custom_command(

src/ContentView.swift

@@ -1,6 +1,8 @@
 import SwiftUI
 
 struct ContentView: View {
+  @Environment(\.scenePhase) private var scenePhase
+
   var body: some View {
     VStack {
       Image(systemName: "globe")
@@ -12,8 +14,12 @@ struct ContentView: View {
     .onAppear {
       // The stupid iOS doesn't show empty directory in Files.app.
       try? "".write(
-        to: FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!
-          .appendingPathComponent("placeholder"), atomically: true, encoding: .utf8)
+        to: documents.appendingPathComponent("placeholder"), atomically: true, encoding: .utf8)
+    }
+    .onChange(of: scenePhase) { newPhase in
+      if newPhase == .active {
+        sync(documents.appendingPathComponent("rime"), appGroupData.appendingPathComponent("rime"))
+      }
     }
   }
 }

src/util.swift

@@ -0,0 +1,71 @@
+import CryptoKit
+import Foundation
+
+let documents = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!
+let appGroupData = FileManager.default.containerURL(
+  forSecurityApplicationGroupIdentifier: "org.fcitx.Fcitx5")!.appendingPathComponent("data")
+
+extension URL {
+  var isDirectory: Bool {
+    (try? resourceValues(forKeys: [.isDirectoryKey]))?.isDirectory == true
+  }
+
+  // Local file name is %-encoded with path()
+  func localPath() -> String {
+    let path = self.path
+    guard let decoded = path.removingPercentEncoding else {
+      return path
+    }
+    return decoded
+  }
+
+  func exists() -> Bool {
+    return FileManager.default.fileExists(atPath: self.path)
+  }
+}
+
+func md5Hash(_ url: URL) -> String {
+  guard let fileData = try? Data(contentsOf: url) else {
+    return ""
+  }
+
+  let digest = Insecure.MD5.hash(data: fileData)
+  return digest.map { String(format: "%02hhx", $0) }.joined()
+}
+
+// Remove if different type, then copy if different content.
+func sync(_ src: URL, _ dst: URL) -> Bool {
+  if !src.exists() {
+    return false
+  }
+  if dst.exists() && dst.isDirectory != src.isDirectory {
+    try? FileManager.default.removeItem(at: dst)
+  }
+  if src.isDirectory {
+    try? FileManager.default.createDirectory(at: dst, withIntermediateDirectories: true)
+    var success = true
+    for fileName in (try? FileManager.default.contentsOfDirectory(atPath: src.localPath())) ?? [] {
+      if !sync(src.appendingPathComponent(fileName), dst.appendingPathComponent(fileName)) {
+        success = false
+      }
+    }
+    return success
+  }
+  if dst.exists() {
+    let srcHash = md5Hash(src)
+    let dstHash = md5Hash(dst)
+    if srcHash == dstHash {
+      return true
+    }
+    try? FileManager.default.removeItem(at: dst)
+  } else if !dst.deletingLastPathComponent().exists() {
+    try? FileManager.default.createDirectory(
+      at: dst.deletingLastPathComponent(), withIntermediateDirectories: true)
+  }
+  do {
+    try FileManager.default.copyItem(at: src, to: dst)
+    return true
+  } catch {
+    return false
+  }
+}