import Flutter
import UIKit

private final class SettingMenuMessenger: NSObject, FlutterBinaryMessenger {
  var selections: [Int] = []
  func send(onChannel channel: String, message: Data?) {
    guard let message else { return }
    let call = FlutterStandardMethodCodec.sharedInstance().decodeMethodCall(message)
    if call.method == "menuAction", let index = call.arguments as? Int {
      selections.append(index)
    }
  }
  func send(onChannel channel: String, message: Data?, binaryReply callback: FlutterBinaryReply?) {
    send(onChannel: channel, message: message)
    callback?(nil)
  }
  func setMessageHandlerOnChannel(
    _ channel: String, binaryMessageHandler handler: FlutterBinaryMessageHandler?
  ) -> FlutterBinaryMessengerConnection { 1 }
  func cleanUpConnection(_ connection: FlutterBinaryMessengerConnection) {}
}

@main
struct SettingMenuSelectionTests {
  @MainActor static func main() {
    let merging = MergingNavigationGlass(frame: CGRect(x: 0, y: 0, width: 256, height: 56))
    merging.layoutIfNeeded()
    UIView.setAnimationsEnabled(false)
    merging.setMenuOpen(true, animator: nil)
    precondition(merging.leftSurface.transform.tx == 100)
    precondition(merging.rightSurface.transform.tx == -100)
    precondition(merging.leftSurface.transform.a == 0.9)
    precondition(merging.leftSurface.alpha == 0 && merging.rightSurface.alpha == 0)
    precondition(merging.centerSurface.alpha == 1)
    merging.setMenuOpen(false, animator: nil)
    precondition(merging.leftSurface.transform == .identity)
    precondition(merging.rightSurface.transform == .identity)
    precondition(merging.leftSurface.alpha == 1 && merging.rightSurface.alpha == 1)
    UIView.setAnimationsEnabled(true)

    for deferred in [false, true] {
      let messenger = SettingMenuMessenger()
      let view = NavigationGlassButtonPlatformView(
        frame: CGRect(x: 0, y: 0, width: 340, height: 56),
        viewIdentifier: 1,
        arguments: [
          "fillWidth": true, "plain": true, "label": "", "enabled": true,
          "deferMenuActions": deferred,
          "menu": [
            ["id": 0, "label": "Low", "enabled": true, "checked": false],
            ["id": 1, "label": "High", "enabled": true, "checked": true],
          ],
        ],
        messenger: messenger
      )
      let button = view.view().subviews.compactMap { $0 as? NavigationGlassButton }.first!
      view.view().layoutIfNeeded()
      view.view().frame.size.width = 600
      view.view().layoutIfNeeded()
      precondition(button.bounds.width == 600)
      precondition(button.point(inside: CGPoint(x: 570, y: 28), with: nil))
      let group = button.menu!.children.first as! UIMenu
      let choices = group.children.compactMap { $0 as? UIAction }
      precondition(choices[0].state == .off && choices[1].state == .on)
      // Invoke the actual menu UIAction through UIKit, without synthesizing a
      // Flutter method-channel message or depending on dismissal callback order.
      let selection = UIButton(primaryAction: choices[0])
      selection.sendActions(for: .touchUpInside)
      precondition(messenger.selections == (deferred ? [] : [0]))
      if deferred {
        precondition(button.pendingMenuAction != nil)
        button.pendingMenuAction?()
        button.pendingMenuAction = nil
        precondition(messenger.selections == [0])
      }
    }
    let messenger = SettingMenuMessenger()
    let grouped = NavigationGlassButtonPlatformView(
      frame: CGRect(x: 0, y: 0, width: 112, height: 56),
      viewIdentifier: 2,
      arguments: ["deferMenuActions": false, "menu": [
        ["id": 0, "label": "New chat", "sectionTitle": "Solo", "enabled": true],
        ["id": 1, "label": "New workspace", "enabled": true],
        ["id": 2, "label": "New DM", "sectionTitle": "Team", "dividerBefore": true, "enabled": true],
        ["id": 3, "label": "New channel", "enabled": true],
      ]], messenger: messenger
    )
    let button = grouped.view().subviews.compactMap { $0 as? NavigationGlassButton }.first!
    precondition(button.preferredMenuElementOrder == .fixed)
    let groups = button.menu!.children.compactMap { $0 as? UIMenu }
    precondition(groups.map(\.title) == ["Solo", "Team"])
    precondition(groups.map { $0.children.count } == [2, 2])
    let teamAction = groups[1].children[0] as! UIAction
    UIButton(primaryAction: teamAction).sendActions(for: .touchUpInside)
    precondition(messenger.selections == [2])
    print("Native setting menu selection checks passed")
  }
}