import AppKit
import VoiceCatCore

final class MoveUserSheet: NSViewController {

    var onComplete: ((UInt32?) -> Void)?

    private let channels: [Channel]
    private let currentChannelId: UInt32
    private let picker = NSPopUpButton()

    init(channels: [Channel], currentChannelId: UInt32) {
        self.channels = channels.sorted(by: { $0.name < $1.name })
        self.currentChannelId = currentChannelId
        super.init(nibName: nil, bundle: nil)
    }

    required init?(coder: NSCoder) { fatalError() }

    override func loadView() {
        view = NSView(frame: NSRect(x: 0, y: 0, width: 300, height: 100))
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        buildUI()
    }

    private func buildUI() {
        let label = NSTextField(labelWithString: "Move user to channel:")
        label.setAccessibilityLabel("Select destination channel")

        for ch in channels where ch.id != currentChannelId {
            let item = NSMenuItem(title: ch.name, action: nil, keyEquivalent: "")
            item.representedObject = ch.id
            picker.menu?.addItem(item)
        }
        picker.setAccessibilityLabel("Destination channel")

        let cancelButton = NSButton(title: "Cancel", target: self, action: #selector(cancelClicked))
        cancelButton.bezelStyle = .rounded

        let moveButton = NSButton(title: "Move", target: self, action: #selector(moveClicked))
        moveButton.bezelStyle = .rounded; moveButton.keyEquivalent = "\r"
        moveButton.setAccessibilityLabel("Move user to selected channel")

        let buttonRow = NSStackView(views: [NSView(), cancelButton, moveButton])
        buttonRow.orientation = .horizontal; buttonRow.spacing = 8

        let stack = NSStackView(views: [label, picker, buttonRow])
        stack.orientation = .vertical; stack.spacing = 10
        stack.edgeInsets = NSEdgeInsets(top: 16, left: 16, bottom: 16, right: 16)
        stack.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(stack)
        NSLayoutConstraint.activate([
            stack.topAnchor.constraint(equalTo: view.topAnchor),
            stack.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            stack.trailingAnchor.constraint(equalTo: view.trailingAnchor),
            stack.bottomAnchor.constraint(equalTo: view.bottomAnchor),
        ])
    }

    @objc private func moveClicked() {
        let channelId = picker.selectedItem?.representedObject as? UInt32
        dismiss(nil)
        onComplete?(channelId)
    }

    @objc private func cancelClicked() {
        dismiss(nil)
        onComplete?(nil)
    }
}