import SwiftUI
import UniformTypeIdentifiers

struct SettingsExportView: View {
  @EnvironmentObject private var settings: SettingsManager
  @State private var isFileExporterPresented = false
  @State private var exportError: Error?

  var body: some View {
    Button("Export Bookmarks") {
      exportBookmarksToFile()
    }
    #if os(macOS)
      .frame(maxWidth: .infinity, alignment: .trailing)
      .fileExporter(
        isPresented: $isFileExporterPresented,
        document: try? JSONFileDocument(settings.exportBookmarks()),
        contentType: .json,
        defaultFilename: "sora_bookmarks.json"
      ) { result in
        switch result {
        case .success:
          break

        case .failure(let error):
          exportError = error
        }
      }
    #endif
    .alert(
      "Export Failed",
      isPresented: Binding(
        get: { exportError != nil },
        set: { if !$0 { exportError = nil } }
      )
    ) {
      Button("OK", role: .cancel) { () }
    } message: {
      Text(exportError?.localizedDescription ?? "An unknown error occurred while exporting.")
    }
  }

  private func exportBookmarksToFile() {
    do {
      #if os(macOS)
        _ = try settings.exportBookmarks()
        isFileExporterPresented = true

      #elseif os(iOS)
        let data = try settings.exportBookmarks()
        let temporaryURL = FileManager.default.temporaryDirectory
          .appendingPathComponent("sora_bookmarks.json")

        try data.write(to: temporaryURL)

        let activityController = UIActivityViewController(
          activityItems: [temporaryURL],
          applicationActivities: nil
        )

        if let windowScene = UIApplication.shared.connectedScenes
          .first(where: { $0.activationState == .foregroundActive }) as? UIWindowScene,
          let rootViewController = windowScene.windows.first?.rootViewController
        {
          activityController.popoverPresentationController?.sourceView = rootViewController.view

          rootViewController.present(activityController, animated: true)
        }

        activityController.completionWithItemsHandler = { _, _, _, _ in
          try? FileManager.default.removeItem(at: temporaryURL)
        }
      #endif
    } catch {
      exportError = error
    }
  }
}