import AppKit

// Application-window specific status view: vertical, one line per item, no marquee.
final class AppStatusView: NSView {
    private let lightSvc = TrafficLight()
    private let lightK3s = TrafficLight()
    private let lightLocal = TrafficLight()

    private let labelSvc = NSTextField(labelWithString: "")
    private let labelK3s = NSTextField(labelWithString: "")
    private let labelLocal = NSTextField(labelWithString: "")

    // Top-right timestamp
    private let timestampLabel: NSTextField = {
        let tf = NSTextField(labelWithString: "0000-00-00 00:00:00 Z")
        tf.font = NSFont.monospacedDigitSystemFont(ofSize: NSFont.systemFontSize(for: .small), weight: .regular)
        tf.textColor = .secondaryLabelColor
        tf.alignment = .right
        tf.translatesAutoresizingMaskIntoConstraints = false
        return tf
    }()

    private var checker: ServiceChecker?
    private let timeFormatter: DateFormatter = {
        let df = DateFormatter()
        df.locale = .current
        df.timeZone = .current
        df.dateFormat = "yyyy-MM-dd HH:mm:ss ZZZZZ"
        return df
    }()

    override init(frame frameRect: NSRect) {
        super.init(frame: frameRect)
        translatesAutoresizingMaskIntoConstraints = false

        // Configure labels
        [labelSvc, labelK3s, labelLocal].forEach { l in
            l.font = NSFont.systemFont(ofSize: NSFont.systemFontSize(for: .regular))
            l.textColor = .labelColor
            l.lineBreakMode = .byTruncatingTail
            l.translatesAutoresizingMaskIntoConstraints = false
        }

        // Rows: [light][label]
        func row(light: NSView, label: NSTextField) -> NSStackView {
            let s = NSStackView(views: [light, label])
            s.orientation = .horizontal
            s.alignment = .centerY
            s.spacing = 8
            s.translatesAutoresizingMaskIntoConstraints = false
            return s
        }

        let row1 = row(light: lightSvc, label: labelSvc)
        let row2 = row(light: lightK3s, label: labelK3s)
        let row3 = row(light: lightLocal, label: labelLocal)

        let vstack = NSStackView(views: [row1, row2, row3])
        vstack.orientation = .vertical
        vstack.alignment = .leading
        vstack.spacing = 10
        vstack.translatesAutoresizingMaskIntoConstraints = false

        addSubview(vstack)
        addSubview(timestampLabel)

        NSLayoutConstraint.activate([
            vstack.leadingAnchor.constraint(equalTo: leadingAnchor, constant: 20),
            vstack.topAnchor.constraint(equalTo: topAnchor, constant: 24),

            timestampLabel.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -16),
            timestampLabel.topAnchor.constraint(equalTo: topAnchor, constant: 10),
            timestampLabel.leadingAnchor.constraint(greaterThanOrEqualTo: vstack.trailingAnchor, constant: 12)
        ])
    }

    required init?(coder: NSCoder) { fatalError("init(coder:) has not been implemented") }

    func bindTo(serviceChecker: ServiceChecker) {
        self.checker = serviceChecker
        NotificationCenter.default.addObserver(self, selector: #selector(updateUI), name: ServiceChecker.statusDidChangeNotification, object: serviceChecker)
        updateUI()
    }

    @objc private func updateUI() {
        guard let c = checker else { return }
        let cfg = Config.shared

        // Timestamp
        let now = Date()
        timestampLabel.stringValue = timeFormatter.string(from: now)

        // SVC
        lightSvc.state = c.svcReachable ? .green : .red
        labelSvc.stringValue = "svc: \(cfg.svcHost):\(cfg.svcPort) \(c.svcReachable ? "✓" : "✗") \(c.svcLatency >= 0 ? "(\(c.svcLatency) ms)" : "")"
        labelSvc.toolTip = c.tooltipForSvc()

        // K3s aggregate: retropie + pi
        let aggCount = (c.raspberryReachable ? 1 : 0) + (c.piReachable ? 1 : 0)
        lightK3s.state = aggCount == 2 ? .green : (aggCount == 1 ? .yellow : .red)
        labelK3s.stringValue = "k3s: \(cfg.retropieHost) \(c.raspberryReachable ? "✓" : "✗"), \(cfg.piHost) \(c.piReachable ? "✓" : "✗")"
        labelK3s.toolTip = c.tooltipForAggregateK3s()

        // Local
        lightLocal.state = c.localReachable ? .green : .red
        labelLocal.stringValue = "local: \(cfg.localHost):\(cfg.localPort) \(c.localReachable ? "✓" : "✗") \(c.localLatency >= 0 ? "(\(c.localLatency) ms)" : "")"
        labelLocal.toolTip = c.tooltipForLocal()

        needsLayout = true
    }
}