import AppKit

final class StatusView: NSView {
    private let light1 = TrafficLight()
    private let light2 = TrafficLight()
    private let light3 = TrafficLight()
    private let lightPF = TrafficLight()
    private let timestampLabel: NSTextField = {
        let tf = NSTextField(labelWithString: "0000-00-00 00:00:00 +00:00")
        tf.textColor = .secondaryLabelColor
        tf.alignment = .left
        tf.font = NSFont.monospacedDigitSystemFont(ofSize: NSFont.systemFontSize(for: .small), weight: .regular)
        tf.setContentHuggingPriority(.required, for: .horizontal)
        tf.setContentCompressionResistancePriority(.required, for: .horizontal)
        return tf
    }()
    private let marquee = MarqueeView()
    private let maximizeButton: NSButton = {
        let b = NSButton(title: "□", target: nil, action: nil)
        b.bezelStyle = .texturedRounded
        b.toolTip = "Show Main Window"
        b.setContentHuggingPriority(.required, for: .horizontal)
        b.setContentCompressionResistancePriority(.required, for: .horizontal)
        return b
    }()

    private var checker: ServiceChecker?
    private let timeFormatter: DateFormatter = {
        let df = DateFormatter()
        df.locale = .current
        df.timeZone = .current
        // Include full date and timezone offset (e.g., 2025-11-17 20:31:05 -08:00)
        df.dateFormat = "yyyy-MM-dd HH:mm:ss ZZZZZ"
        return df
    }()
    private let fullFormatter: DateFormatter = {
        let df = DateFormatter()
        df.locale = .current
        df.timeZone = .current
        df.dateStyle = .medium
        df.timeStyle = .medium
        return df
    }()

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

        let stack = NSStackView(views: [light1, light2, light3, lightPF, timestampLabel, marquee, maximizeButton])
        stack.orientation = .horizontal
        stack.alignment = .centerY
        stack.distribution = .equalSpacing
        stack.spacing = 12
        stack.translatesAutoresizingMaskIntoConstraints = false

        addSubview(stack)
        NSLayoutConstraint.activate([
            stack.centerXAnchor.constraint(equalTo: centerXAnchor),
            stack.centerYAnchor.constraint(equalTo: centerYAnchor)
        ])

        // Wire button actions
        maximizeButton.target = self
        maximizeButton.action = #selector(didTapMaximize)

        // Tracking for hover tooltips
        addTrackingArea(NSTrackingArea(rect: bounds, options: [.mouseEnteredAndExited, .mouseMoved, .activeAlways, .inVisibleRect], owner: self, userInfo: nil))

        // Configure marquee width to be ~64 monospace characters
        configureMarqueeWidth()
    }

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

    override func hitTest(_ point: NSPoint) -> NSView? {
        // Allow interaction with our inline controls and status lights (for tooltips),
        // pass other clicks through to avoid blocking the menu bar.
        if let v = super.hitTest(point) {
            if v is NSButton { return v }
            if v is TrafficLight { return v }
            if let tl = v.toolTip, !tl.isEmpty { return v }
        }
        return nil
    }

    private var pfManager: PortForwardManager?

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

    func setPortForwardManager(_ manager: PortForwardManager?) {
        self.pfManager = manager
        if let m = manager {
            NotificationCenter.default.addObserver(self, selector: #selector(updateLights), name: PortForwardManager.statusDidChangeNotification, object: m)
        }
        updateLights()
    }

    @objc private func updateLights() {
        guard let c = checker else { return }
        // Light 1: svc.prole.org:443
        light1.state = c.svcReachable ? .green : .red
        light1.toolTip = c.tooltipForSvc()

        // Light 2: aggregate raspberry + pi
        let count = (c.raspberryReachable ? 1 : 0) + (c.piReachable ? 1 : 0)
        light2.state = count == 2 ? .green : (count == 1 ? .yellow : .red)
        light2.toolTip = c.tooltipForAggregateK3s()

        // Light 3: localhost k3d
        light3.state = c.localReachable ? .green : .red
        light3.toolTip = c.tooltipForLocal()

        // Light 4: port-forward supervision status (Dev)
        if let m = pfManager {
            lightPF.state = m.allRunning ? .green : .red
            lightPF.toolTip = m.allRunning ? "kubectl port-forwards: running" : "kubectl port-forwards: not all running"
        } else {
            lightPF.state = .red
            lightPF.toolTip = "kubectl port-forwards: disabled"
        }

        // Timestamp label
        let now = Date()
        timestampLabel.stringValue = timeFormatter.string(from: now)
        timestampLabel.toolTip = "Last updated: " + fullFormatter.string(from: now)

        // Update marquee text with status summary and ensure it scrolls
        let msg = aggregateStatusSummary()
        marquee.setText(msg)
        marquee.toolTip = msg
        needsDisplay = true
    }

    func aggregateStatusSummary() -> String {
        guard let c = checker else { return "No status" }
        let cfg = Config.shared
        let svc = c.svcReachable ? "\(cfg.svcHost):\(cfg.svcPort) ✓" : "\(cfg.svcHost):\(cfg.svcPort) ✗"
        let agg = "k3s: \(cfg.retropieHost) \(c.raspberryReachable ? "✓" : "✗"), \(cfg.piHost) \(c.piReachable ? "✓" : "✗")"
        let loc = c.localReachable ? "k3d \(cfg.localHost):\(cfg.localPort) ✓" : "k3d \(cfg.localHost):\(cfg.localPort) ✗"
        return [svc, agg, loc].joined(separator: "  •  ")
    }

    // MARK: - Button actions
    @objc private func didTapMaximize() {
        NotificationCenter.default.post(name: .toggleMode, object: nil)
    }
}

// MARK: - MarqueeView
final class MarqueeView: NSView {
    private let scrollClip = NSView()
    private let label1 = NSTextField(labelWithString: "")
    private let label2 = NSTextField(labelWithString: "")
    private var timer: Timer?
    // Slow down by one third: 60 → 40 pts/sec
    private var speedPointsPerSec: CGFloat = 40.0 // horizontal speed
    private var lastTick: TimeInterval = CACurrentMediaTime()
    private var currentText: String = ""

    // Public width constraint can be set by container; we keep hugging low so it expands to fixed width
    override init(frame frameRect: NSRect) {
        super.init(frame: frameRect)
        translatesAutoresizingMaskIntoConstraints = false
        wantsLayer = false

        scrollClip.wantsLayer = false
        scrollClip.translatesAutoresizingMaskIntoConstraints = false
        addSubview(scrollClip)

        // Configure labels
        for lbl in [label1, label2] {
            lbl.font = NSFont.monospacedSystemFont(ofSize: NSFont.systemFontSize(for: .small), weight: .regular)
            lbl.textColor = .secondaryLabelColor
            lbl.alignment = .left
            lbl.backgroundColor = .clear
            lbl.isBezeled = false
            lbl.drawsBackground = false
            lbl.lineBreakMode = .byClipping
            lbl.translatesAutoresizingMaskIntoConstraints = true // we will manage frames manually
        }

        scrollClip.addSubview(label1)
        scrollClip.addSubview(label2)

        // Clip to bounds so text scrolls inside
        wantsLayer = true
        layer?.masksToBounds = true

        setContentHuggingPriority(.defaultLow, for: .horizontal)
        setContentCompressionResistancePriority(.defaultLow, for: .horizontal)

        NSLayoutConstraint.activate([
            scrollClip.leadingAnchor.constraint(equalTo: leadingAnchor),
            scrollClip.trailingAnchor.constraint(equalTo: trailingAnchor),
            scrollClip.topAnchor.constraint(equalTo: topAnchor),
            scrollClip.bottomAnchor.constraint(equalTo: bottomAnchor)
        ])

        start()
    }

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

    override func viewDidMoveToWindow() {
        super.viewDidMoveToWindow()
        if window != nil { start() } else { stop() }
    }

    override func layout() {
        super.layout()
        layoutLabelsIfNeeded()
    }

    override func hitTest(_ point: NSPoint) -> NSView? { nil } // click-through

    func setText(_ text: String) {
        if text == currentText { return }
        currentText = text
        label1.stringValue = text + String(repeating: " ", count: 8)
        label2.stringValue = label1.stringValue
        layoutLabelsIfNeeded(resetOffset: true)
    }

    private func layoutLabelsIfNeeded(resetOffset: Bool = false) {
        let h = bounds.height
        let y = (h - intrinsicLineHeight())/2.0
        let size = label1.intrinsicContentSize
        let w = size.width
        // Place labels back-to-back for seamless loop
        if resetOffset {
            label1.frame = NSRect(x: 0, y: y, width: w, height: size.height)
            label2.frame = NSRect(x: w, y: y, width: w, height: size.height)
        } else if label1.frame.size.width == 0 || label2.frame.size.width == 0 {
            label1.frame = NSRect(x: label1.frame.origin.x, y: y, width: w, height: size.height)
            label2.frame = NSRect(x: label2.frame.origin.x, y: y, width: w, height: size.height)
        } else {
            // Keep vertically centered
            label1.frame.origin.y = y
            label2.frame.origin.y = y
        }
    }

    private func intrinsicLineHeight() -> CGFloat {
        let f = label1.font ?? NSFont.monospacedSystemFont(ofSize: NSFont.systemFontSize(for: .small), weight: .regular)
        return ceil(f.ascender - f.descender)
    }

    private func tick() {
        let now = CACurrentMediaTime()
        let dt = now - lastTick
        lastTick = now
        let dx = CGFloat(dt) * speedPointsPerSec

        // Move both labels left by dx
        label1.frame.origin.x -= dx
        label2.frame.origin.x -= dx

        // When a label fully leaves on the left, move it to the right of the other
        if label1.frame.maxX <= 0 {
            label1.frame.origin.x = label2.frame.maxX
        }
        if label2.frame.maxX <= 0 {
            label2.frame.origin.x = label1.frame.maxX
        }
    }

    func start() {
        stop()
        lastTick = CACurrentMediaTime()
        timer = Timer.scheduledTimer(withTimeInterval: 1.0/60.0, repeats: true) { [weak self] _ in
            self?.tick()
        }
        RunLoop.main.add(timer!, forMode: .common)
    }

    func stop() {
        timer?.invalidate()
        timer = nil
    }

    deinit { stop() }
}

// Utility to compute width for N monospace characters
private func widthForMonospaceCharacters(_ count: Int, font: NSFont) -> CGFloat {
    let sample = String(repeating: "0", count: max(1, count))
    let attrs: [NSAttributedString.Key: Any] = [.font: font]
    let w = (sample as NSString).size(withAttributes: attrs).width
    return ceil(w)
}

private extension StatusView {
    func configureMarqueeWidth() {
        // Match font with timestamp for visual cohesion
        let font = NSFont.monospacedSystemFont(ofSize: NSFont.systemFontSize(for: .small), weight: .regular)
        marquee.heightAnchor.constraint(equalToConstant: ceil(font.capHeight * 1.8)).isActive = true
        let width = widthForMonospaceCharacters(64, font: font)
        let wConstraint = marquee.widthAnchor.constraint(equalToConstant: width)
        wConstraint.priority = .required
        wConstraint.isActive = true
    }
}

// MARK: - Notification bridge
extension Notification.Name {
    static let showMainWindow = Notification.Name("ProleStatus.showMainWindow")
    static let toggleMode = Notification.Name("ProleStatus.toggleMode")
}

final class TrafficLight: NSView {
    enum State { case green, yellow, red }
    var state: State = .red { didSet { needsDisplay = true } }

    override var intrinsicContentSize: NSSize { NSSize(width: 14, height: 14) }

    override func draw(_ dirtyRect: NSRect) {
        super.draw(dirtyRect)
        let rect = bounds.insetBy(dx: 1, dy: 1)
        let path = NSBezierPath(ovalIn: rect)
        let color: NSColor
        switch state {
        case .green: color = NSColor.systemGreen
        case .yellow: color = NSColor.systemYellow
        case .red: color = NSColor.systemRed
        }
        color.setFill()
        path.fill()

        // subtle ring for better contrast against menu material
        NSColor.black.withAlphaComponent(0.12).setStroke()
        path.lineWidth = 1
        path.stroke()
    }
}