import Cocoa
import FlutterMacOS

class WindowDelegate: NSObject, NSWindowDelegate {
  weak var channel: FlutterMethodChannel?
  weak var window: NSWindow?

  // Hardcoded presentation options for fullscreen mode
  // Auto-hide toolbar, menu bar, and dock when in fullscreen
  private let fullScreenPresentationOptions: NSApplication.PresentationOptions = [
    .fullScreen,
    .autoHideToolbar,
    .autoHideMenuBar,
    .autoHideDock,
  ]

  // MARK: - Private Helpers

  private func emit(_ method: String) {
    channel?.invokeMethod(method, arguments: nil)
  }

  // MARK: - NSWindowDelegate

  func window(
    _ window: NSWindow,
    willUseFullScreenPresentationOptions proposedOptions: NSApplication.PresentationOptions
  ) -> NSApplication.PresentationOptions {
    return fullScreenPresentationOptions
  }

  func windowWillEnterFullScreen(_ notification: Notification) {
    guard let window = window else { return }
    // Remove toolbar before entering fullscreen
    window.toolbar = nil
    // Show title and make titlebar opaque for native fullscreen look
    window.titleVisibility = .visible
    window.titlebarAppearsTransparent = false
    // Reset traffic light positions to default
    WindowUtilsPlugin.setTrafficLightPositions(custom: false, window: window)
    // Notify Dart for state management only
    emit("windowWillEnterFullScreen")
  }

  func windowDidEnterFullScreen(_ notification: Notification) {
    emit("windowDidEnterFullScreen")
  }

  func windowWillExitFullScreen(_ notification: Notification) {
    guard let window = window else { return }
    // Hide title and make titlebar transparent BEFORE exiting
    window.titleVisibility = .hidden
    window.titlebarAppearsTransparent = true
    emit("windowWillExitFullScreen")
  }

  func windowDidExitFullScreen(_ notification: Notification) {
    guard let window = window else { return }
    // Restore toolbar
    if let flutterVC = window.contentViewController {
      let toolbar = ForwardingToolbar(flutterViewController: flutterVC)
      window.toolbar = toolbar
    }
    // Restore custom traffic light positions
    WindowUtilsPlugin.setTrafficLightPositions(custom: true, window: window)
    emit("windowDidExitFullScreen")
  }
}