import AppKit
import VoiceCatCore

final class PerUserTuningSheet: NSViewController {

    private let client: VoiceCatClient
    private let userId: UInt32
    private let nickname: String

    private var streams: [StreamSummary] = []
    private var rows: [StreamRow] = []

    private struct StreamRow {
        let streamId: UInt32
        let label: String
        let gainSlider: NSSlider
        let muteCheckbox: NSButton
        let nrCheckbox: NSButton
    }

    init(client: VoiceCatClient, userId: UInt32, nickname: String) {
        self.client = client
        self.userId = userId
        self.nickname = nickname
        super.init(nibName: nil, bundle: nil)
    }

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

    override func loadView() {
        view = NSView(frame: NSRect(x: 0, y: 0, width: 400, height: 200))
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        streams = client.listUserStreams(userId)
        buildUI()
    }

    private func buildUI() {
        let titleLabel = NSTextField(labelWithString: "Volume & Noise Settings — \(nickname)")
        titleLabel.font = .boldSystemFont(ofSize: 13)

        var rowViews: [NSView] = [titleLabel]

        for stream in streams {
            let (_, state) = client.getRemoteStream(userId: userId, streamId: stream.id)
            let gain = state?.gain ?? 1.0
            let muted = state?.muted ?? false
            let nr = state?.noiseReduction ?? false

            let gainSlider = NSSlider(value: Double(gain * 100), minValue: 0, maxValue: 200, target: self, action: #selector(sliderChanged))
            gainSlider.tag = Int(stream.id)
            gainSlider.numberOfTickMarks = 0
            gainSlider.setAccessibilityLabel("Volume for \(stream.label): \(Int(gain * 100)) percent")

            let muteCheckbox = NSButton(checkboxWithTitle: "Mute", target: self, action: #selector(muteChanged))
            muteCheckbox.state = muted ? .on : .off
            muteCheckbox.tag = Int(stream.id)
            muteCheckbox.setAccessibilityLabel("Mute \(stream.label)")

            let nrCheckbox = NSButton(checkboxWithTitle: "Noise reduction", target: self, action: #selector(nrChanged))
            nrCheckbox.state = nr ? .on : .off
            nrCheckbox.tag = Int(stream.id)
            nrCheckbox.setAccessibilityLabel("Noise reduction for \(stream.label)")

            let streamLabel = NSTextField(labelWithString: "\(stream.label):")
            let gainLabel = NSTextField(labelWithString: "Volume:")
            let row = NSStackView(views: [streamLabel, gainLabel, gainSlider, muteCheckbox, nrCheckbox])
            row.orientation = .horizontal; row.spacing = 8
            rowViews.append(row)

            rows.append(StreamRow(streamId: stream.id, label: stream.label,
                                  gainSlider: gainSlider, muteCheckbox: muteCheckbox,
                                  nrCheckbox: nrCheckbox))
        }

        if streams.isEmpty {
            rowViews.append(NSTextField(labelWithString: "This user has no active streams."))
        }

        let doneButton = NSButton(title: "Done", target: self, action: #selector(doneClicked))
        doneButton.bezelStyle = .rounded; doneButton.keyEquivalent = "\r"
        doneButton.setAccessibilityLabel("Close settings")
        rowViews.append(NSStackView(views: [NSView(), doneButton]))

        let stack = NSStackView(views: rowViews)
        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),
        ])
    }

    @objc private func sliderChanged(_ sender: NSSlider) {
        apply(streamId: UInt32(sender.tag))
    }

    @objc private func muteChanged(_ sender: NSButton) {
        apply(streamId: UInt32(sender.tag))
    }

    @objc private func nrChanged(_ sender: NSButton) {
        apply(streamId: UInt32(sender.tag))
    }

    private func apply(streamId: UInt32) {
        guard let row = rows.first(where: { $0.streamId == streamId }) else { return }
        let gain = Float(row.gainSlider.doubleValue) / 100.0
        let muted = row.muteCheckbox.state == .on
        let nr = row.nrCheckbox.state == .on
        client.setRemoteStream(userId: userId, streamId: streamId,
                               gain: gain, muted: muted, noiseReduction: nr)
        row.gainSlider.setAccessibilityLabel("Volume for \(row.label): \(Int(row.gainSlider.doubleValue)) percent")
    }

    @objc private func doneClicked() { dismiss(nil) }
}