import AppKit

final class SplashTipWindowController: NSWindowController {
    private let imageView = NSImageView()
    private let tipLabel = NSTextField(labelWithString: "Tip: Press Cmd+Opt+Shift+P to change modes")
    private let counterLabel = NSTextField(labelWithString: "0.0")
    private var timer: DispatchSourceTimer?
    private var startTime: DispatchTime?
    private let displayDuration: TimeInterval = 5.0

    init() {
        let style: NSWindow.StyleMask = [.borderless]
        let initialRect = NSRect(x: 0, y: 0, width: 520, height: 360)
        let window = NSWindow(contentRect: initialRect, styleMask: style, backing: .buffered, defer: false)
        super.init(window: window)

        window.isReleasedWhenClosed = false
        // Light theme background
        window.backgroundColor = NSColor(calibratedWhite: 1.0, alpha: 0.96)
        window.isOpaque = false
        window.hasShadow = true
        window.level = .floating
        window.collectionBehavior = [.canJoinAllSpaces]
        window.titleVisibility = .hidden
        window.titlebarAppearsTransparent = true
        window.appearance = NSAppearance(named: .aqua)

        let content = NSView()
        content.wantsLayer = true
        content.translatesAutoresizingMaskIntoConstraints = false
        window.contentView = content

        imageView.translatesAutoresizingMaskIntoConstraints = false
        imageView.imageScaling = .scaleProportionallyUpOrDown
        imageView.animates = true

        tipLabel.translatesAutoresizingMaskIntoConstraints = false
        tipLabel.font = NSFont.systemFont(ofSize: 14, weight: .semibold)
        tipLabel.textColor = .labelColor
        tipLabel.alignment = .center
        tipLabel.lineBreakMode = .byWordWrapping
        tipLabel.maximumNumberOfLines = 2

        counterLabel.translatesAutoresizingMaskIntoConstraints = false
        counterLabel.font = NSFont.monospacedSystemFont(ofSize: 10, weight: .regular)
        counterLabel.textColor = NSColor(white: 0.1, alpha: 0.85)
        counterLabel.alignment = .left

        content.addSubview(imageView)
        content.addSubview(tipLabel)
        content.addSubview(counterLabel)

        NSLayoutConstraint.activate([
            content.widthAnchor.constraint(equalToConstant: initialRect.width),
            content.heightAnchor.constraint(equalToConstant: initialRect.height),

            imageView.topAnchor.constraint(equalTo: content.topAnchor, constant: 20),
            imageView.leadingAnchor.constraint(equalTo: content.leadingAnchor, constant: 20),
            imageView.trailingAnchor.constraint(equalTo: content.trailingAnchor, constant: -20),
            imageView.heightAnchor.constraint(equalToConstant: 260),

            tipLabel.topAnchor.constraint(equalTo: imageView.bottomAnchor, constant: 12),
            tipLabel.leadingAnchor.constraint(equalTo: content.leadingAnchor, constant: 20),
            tipLabel.trailingAnchor.constraint(equalTo: content.trailingAnchor, constant: -20),

            counterLabel.leadingAnchor.constraint(equalTo: content.leadingAnchor, constant: 6),
            counterLabel.bottomAnchor.constraint(equalTo: content.bottomAnchor, constant: -4)
        ])

        // Load background/splash image from config (bundled in Resources) if present
        let bgName = Config.shared.uiBackground
        let candidates: [(String, String?)] = [
            (bgName, nil),
            ("prole-type", "gif")
        ]
        var loaded = false
        for (res, ext) in candidates {
            if let url = Bundle.main.url(forResource: res, withExtension: ext),
               let img = NSImage(contentsOf: url) {
                imageView.image = img
                loaded = true
                break
            }
        }
        if !loaded {
            // Fallback: show placeholder text if the resource is missing
            let placeholder = NSTextField(labelWithString: "Splash background not found")
            placeholder.textColor = .secondaryLabelColor
            placeholder.alignment = .center
            placeholder.translatesAutoresizingMaskIntoConstraints = false
            content.addSubview(placeholder)
            NSLayoutConstraint.activate([
                placeholder.centerXAnchor.constraint(equalTo: imageView.centerXAnchor),
                placeholder.centerYAnchor.constraint(equalTo: imageView.centerYAnchor)
            ])
        }

        // Click anywhere to dismiss early
        let clickRecognizer = NSClickGestureRecognizer(target: self, action: #selector(dismissSplash))
        content.addGestureRecognizer(clickRecognizer)
    }

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

    func show() {
        guard let screen = NSScreen.main, let window = window else { return }
        let frame = window.frame
        let x = screen.visibleFrame.midX - frame.width / 2
        let y = screen.visibleFrame.midY - frame.height / 2
        window.setFrame(NSRect(x: x, y: y, width: frame.width, height: frame.height), display: true)
        window.orderFrontRegardless()
        NSApp.activate(ignoringOtherApps: false)

        // Start counter timer
        startTime = .now()
        let timer = DispatchSource.makeTimerSource(queue: .main)
        timer.schedule(deadline: .now(), repeating: .milliseconds(100))
        timer.setEventHandler { [weak self] in
            self?.tick()
        }
        timer.resume()
        self.timer = timer

        // Auto dismiss after duration
        DispatchQueue.main.asyncAfter(deadline: .now() + displayDuration) { [weak self] in
            self?.dismissSplash()
        }
    }

    private func tick() {
        guard let start = startTime else { return }
        let elapsed = DispatchTime.now().uptimeNanoseconds - start.uptimeNanoseconds
        let seconds = Double(elapsed) / 1_000_000_000.0
        let whole = Int(seconds)
        let tenths = Int((seconds - Double(whole)) * 10.0)
        counterLabel.stringValue = String(format: "%d.%d", whole, tenths)
    }

    @objc private func dismissSplash() {
        timer?.cancel()
        timer = nil
        window?.orderOut(nil)
        close()
    }
}