import Cocoa
import QuartzCore

public enum HUDState {
    case hidden
    case recording(level: Float, isLagging: Bool = false)
    case retrying
    case transcribing
    case success
    case error
}

public final class HUDOverlayController {
    public static let shared = HUDOverlayController()
    
    private var window: NSPanel?
    private var orbView: SiriOrbView?
    private var isVisible = false
    
    // Large canvas so shadows/halos NEVER clip at window boundaries
    private let canvasSize: CGFloat = 260
    
    private init() {
        DispatchQueue.main.async {
            self.setupWindow()
        }
    }
    
    private func setupWindow() {
        let panel = NSPanel(
            contentRect: NSRect(x: 0, y: 0, width: canvasSize, height: canvasSize),
            styleMask: [.borderless, .nonactivatingPanel],
            backing: .buffered,
            defer: false
        )
        panel.isOpaque = false
        panel.backgroundColor = .clear
        panel.level = .floating
        panel.collectionBehavior = [.canJoinAllSpaces, .fullScreenAuxiliary, .stationary]
        panel.hasShadow = false
        panel.ignoresMouseEvents = true
        panel.alphaValue = 0.0
        
        let container = NSView(frame: panel.contentView!.bounds)
        container.wantsLayer = true
        
        // Siri-like Circular Orb centered with plenty of breathing room for glowing halos
        let orbSize: CGFloat = 64
        let orbOrigin = (canvasSize - orbSize) / 2.0
        let orb = SiriOrbView(frame: NSRect(x: orbOrigin, y: orbOrigin, width: orbSize, height: orbSize))
        container.addSubview(orb)
        self.orbView = orb
        
        panel.contentView = container
        self.window = panel
        reposition()
    }
    
    private func reposition() {
        guard let window = self.window, let screen = NSScreen.main else { return }
        let screenRect = screen.visibleFrame
        // Center horizontally, position near bottom of screen
        let x = screenRect.midX - (canvasSize / 2.0)
        let y = screenRect.minY + 12
        window.setFrameOrigin(NSPoint(x: x, y: y))
    }
    
    public func show(state: HUDState) {
        DispatchQueue.main.async { [weak self] in
            guard let self = self else { return }
            if self.window == nil {
                self.setupWindow()
            }
            guard let window = self.window, let orb = self.orbView else { return }
            self.reposition()
            
            switch state {
            case .hidden:
                self.hide()
                
            case .recording(let level, let isLagging):
                if !self.isVisible {
                    window.orderFrontRegardless()
                    window.animator().alphaValue = 1.0
                    self.isVisible = true
                }
                orb.updateAudioLevel(level, isLagging: isLagging)
                
            case .retrying:
                if !self.isVisible {
                    window.orderFrontRegardless()
                    window.animator().alphaValue = 1.0
                    self.isVisible = true
                }
                orb.showRetryState()
                
            case .transcribing:
                orb.showTranscribingState()
                
            case .success:
                orb.showSuccessState()
                DispatchQueue.main.asyncAfter(deadline: .now() + 0.45) {
                    self.hide()
                }
                
            case .error:
                orb.showErrorState()
                DispatchQueue.main.asyncAfter(deadline: .now() + 0.75) {
                    self.hide()
                }
            }
        }
    }
    
    public func hide() {
        DispatchQueue.main.async { [weak self] in
            guard let self = self, let window = self.window, self.isVisible else { return }
            NSAnimationContext.runAnimationGroup({ context in
                context.duration = 0.20
                window.animator().alphaValue = 0.0
            }, completionHandler: {
                window.orderOut(nil)
                self.isVisible = false
                self.orbView?.reset()
            })
        }
    }
}

// MARK: - Premium Apple Intelligence / Siri Multilayer Glowing Orb

final class SiriOrbView: NSView {
    private let ambientAuraLayer = CALayer()
    private let haloLayer = CALayer()
    private let acousticRippleLayer = CALayer()
    private let glassBackdrop = CALayer()
    private let siriGradientLayer = CAGradientLayer()
    private let specularHighlight = CAGradientLayer()
    
    override init(frame frameRect: NSRect) {
        super.init(frame: frameRect)
        wantsLayer = true
        setupLayers()
    }
    
    required init?(coder: NSCoder) {
        super.init(coder: coder)
        wantsLayer = true
        setupLayers()
    }
    
    private func setupLayers() {
        guard let layer = self.layer else { return }
        layer.masksToBounds = false
        
        let bounds = self.bounds
        let radius = bounds.width / 2.0
        
        // 1. Deep Ambient Soft Aura (Diffused outer glow)
        ambientAuraLayer.frame = bounds.insetBy(dx: -32, dy: -32)
        ambientAuraLayer.cornerRadius = (bounds.width + 64) / 2.0
        ambientAuraLayer.backgroundColor = NSColor(red: 0.0, green: 0.65, blue: 1.0, alpha: 0.22).cgColor
        ambientAuraLayer.shadowColor = NSColor(red: 0.55, green: 0.0, blue: 1.0, alpha: 0.85).cgColor
        ambientAuraLayer.shadowRadius = 38
        ambientAuraLayer.shadowOpacity = 0.95
        ambientAuraLayer.shadowOffset = .zero
        layer.addSublayer(ambientAuraLayer)
        
        // 2. Focused Neon Halo
        haloLayer.frame = bounds.insetBy(dx: -14, dy: -14)
        haloLayer.cornerRadius = (bounds.width + 28) / 2.0
        haloLayer.backgroundColor = NSColor(red: 0.1, green: 0.8, blue: 1.0, alpha: 0.40).cgColor
        haloLayer.shadowColor = NSColor(red: 0.0, green: 0.9, blue: 1.0, alpha: 0.85).cgColor
        haloLayer.shadowRadius = 18
        haloLayer.shadowOpacity = 0.9
        haloLayer.shadowOffset = .zero
        layer.addSublayer(haloLayer)
        
        // 3. Acoustic Ripple Ring
        acousticRippleLayer.frame = bounds.insetBy(dx: -4, dy: -4)
        acousticRippleLayer.cornerRadius = (bounds.width + 8) / 2.0
        acousticRippleLayer.borderColor = NSColor(red: 0.0, green: 0.95, blue: 1.0, alpha: 0.35).cgColor
        acousticRippleLayer.borderWidth = 1.5
        layer.addSublayer(acousticRippleLayer)
        
        // 4. Dark Glass Spherical Backdrop
        glassBackdrop.frame = bounds
        glassBackdrop.cornerRadius = radius
        glassBackdrop.backgroundColor = NSColor.black.withAlphaComponent(0.85).cgColor
        glassBackdrop.borderColor = NSColor.white.withAlphaComponent(0.35).cgColor
        glassBackdrop.borderWidth = 1.0
        layer.addSublayer(glassBackdrop)
        
        // 5. Multi-Color Liquid Siri Gradient Core
        siriGradientLayer.frame = bounds.insetBy(dx: 3, dy: 3)
        siriGradientLayer.cornerRadius = (bounds.width - 6) / 2.0
        siriGradientLayer.type = .radial
        siriGradientLayer.colors = [
            NSColor(red: 0.0, green: 0.95, blue: 1.0, alpha: 1.0).cgColor,   // Electric Cyan Center
            NSColor(red: 0.50, green: 0.12, blue: 1.0, alpha: 0.95).cgColor, // Royal Violet
            NSColor(red: 0.98, green: 0.08, blue: 0.65, alpha: 0.90).cgColor, // Hot Magenta
            NSColor(red: 0.10, green: 0.20, blue: 0.95, alpha: 0.85).cgColor  // Deep Blue
        ]
        siriGradientLayer.startPoint = CGPoint(x: 0.35, y: 0.35)
        siriGradientLayer.endPoint = CGPoint(x: 1.0, y: 1.0)
        layer.addSublayer(siriGradientLayer)
        
        // 6. 3D Curved Specular Glass Crescent Highlight (Apple Intelligence style)
        specularHighlight.frame = NSRect(x: bounds.midX - 18, y: bounds.maxY - 18, width: 36, height: 12)
        specularHighlight.cornerRadius = 6
        specularHighlight.colors = [
            NSColor.white.withAlphaComponent(0.65).cgColor,
            NSColor.white.withAlphaComponent(0.0).cgColor
        ]
        specularHighlight.startPoint = CGPoint(x: 0.5, y: 1.0)
        specularHighlight.endPoint = CGPoint(x: 0.5, y: 0.0)
        layer.addSublayer(specularHighlight)
        
        // Start fluid rotation
        startOrbRotation()
    }
    
    private func startOrbRotation() {
        let rotate = CABasicAnimation(keyPath: "transform.rotation.z")
        rotate.fromValue = 0.0
        rotate.toValue = 2 * Double.pi
        rotate.duration = 4.0
        rotate.repeatCount = .infinity
        rotate.isRemovedOnCompletion = false
        siriGradientLayer.add(rotate, forKey: "siriFluidRotate")
    }
    
    func updateAudioLevel(_ level: Float, isLagging: Bool) {
        CATransaction.begin()
        CATransaction.setDisableActions(true)
        
        let clamped = CGFloat(min(max(level, 0.0), 1.0))
        
        if isLagging {
            // Warm amber pulse for weak internet
            siriGradientLayer.colors = [
                NSColor(red: 1.0, green: 0.85, blue: 0.2, alpha: 1.0).cgColor,
                NSColor(red: 1.0, green: 0.55, blue: 0.0, alpha: 0.95).cgColor,
                NSColor(red: 0.95, green: 0.25, blue: 0.0, alpha: 0.90).cgColor
            ]
            haloLayer.backgroundColor = NSColor(red: 1.0, green: 0.5, blue: 0.0, alpha: 0.5).cgColor
            haloLayer.shadowColor = NSColor(red: 1.0, green: 0.4, blue: 0.0, alpha: 0.9).cgColor
            ambientAuraLayer.shadowColor = NSColor(red: 1.0, green: 0.3, blue: 0.0, alpha: 0.7).cgColor
        } else {
            // High-fidelity Siri electric gradient
            siriGradientLayer.colors = [
                NSColor(red: 0.0, green: 0.95, blue: 1.0, alpha: 1.0).cgColor,
                NSColor(red: 0.50, green: 0.12, blue: 1.0, alpha: 0.95).cgColor,
                NSColor(red: 0.98, green: 0.08, blue: 0.65, alpha: 0.90).cgColor,
                NSColor(red: 0.10, green: 0.20, blue: 0.95, alpha: 0.85).cgColor
            ]
            haloLayer.backgroundColor = NSColor(red: 0.1, green: 0.8, blue: 1.0, alpha: 0.40).cgColor
            haloLayer.shadowColor = NSColor(red: 0.0, green: 0.9, blue: 1.0, alpha: 0.85).cgColor
            ambientAuraLayer.shadowColor = NSColor(red: 0.55, green: 0.0, blue: 1.0, alpha: 0.85).cgColor
        }
        
        // Massive Audio Dynamic Scaling (Orb expands up to 1.65x with voice)
        let scale = 1.0 + (clamped * 0.65)
        self.layer?.sublayerTransform = CATransform3DMakeScale(scale, scale, 1.0)
        
        // Dynamic Halo bloom (Expands smoothly up to 55px radius)
        haloLayer.shadowRadius = 18 + (clamped * 36)
        haloLayer.shadowOpacity = Float(0.75 + (clamped * 0.25))
        ambientAuraLayer.shadowRadius = 38 + (clamped * 42)
        
        // Acoustic ripple expands outward
        let rippleScale = 1.0 + (clamped * 0.35)
        acousticRippleLayer.transform = CATransform3DMakeScale(rippleScale, rippleScale, 1.0)
        acousticRippleLayer.opacity = Float(0.3 + (clamped * 0.7))
        
        CATransaction.commit()
    }
    
    func showRetryState() {
        CATransaction.begin()
        CATransaction.setDisableActions(false)
        CATransaction.setAnimationDuration(0.3)
        siriGradientLayer.colors = [
            NSColor(red: 1.0, green: 0.85, blue: 0.2, alpha: 1.0).cgColor,
            NSColor(red: 1.0, green: 0.50, blue: 0.0, alpha: 0.95).cgColor,
            NSColor(red: 0.95, green: 0.20, blue: 0.0, alpha: 0.90).cgColor
        ]
        haloLayer.shadowColor = NSColor.orange.cgColor
        ambientAuraLayer.shadowColor = NSColor.orange.cgColor
        CATransaction.commit()
    }
    
    func showTranscribingState() {
        CATransaction.begin()
        CATransaction.setDisableActions(true)
        self.layer?.sublayerTransform = CATransform3DMakeScale(1.08, 1.08, 1.0)
        CATransaction.commit()
    }
    
    func showSuccessState() {
        CATransaction.begin()
        CATransaction.setDisableActions(false)
        CATransaction.setAnimationDuration(0.2)
        siriGradientLayer.colors = [
            NSColor(red: 0.2, green: 1.0, blue: 0.5, alpha: 1.0).cgColor,
            NSColor(red: 0.0, green: 0.85, blue: 0.8, alpha: 0.95).cgColor
        ]
        haloLayer.shadowColor = NSColor.green.cgColor
        ambientAuraLayer.shadowColor = NSColor.green.cgColor
        CATransaction.commit()
    }
    
    func showErrorState() {
        CATransaction.begin()
        CATransaction.setDisableActions(false)
        CATransaction.setAnimationDuration(0.2)
        siriGradientLayer.colors = [
            NSColor(red: 1.0, green: 0.2, blue: 0.2, alpha: 1.0).cgColor,
            NSColor(red: 0.8, green: 0.0, blue: 0.4, alpha: 0.95).cgColor
        ]
        haloLayer.shadowColor = NSColor.red.cgColor
        ambientAuraLayer.shadowColor = NSColor.red.cgColor
        CATransaction.commit()
    }
    
    func reset() {
        CATransaction.begin()
        CATransaction.setDisableActions(true)
        self.layer?.sublayerTransform = CATransform3DIdentity
        haloLayer.shadowRadius = 18
        ambientAuraLayer.shadowRadius = 38
        acousticRippleLayer.transform = CATransform3DIdentity
        acousticRippleLayer.opacity = 0.3
        CATransaction.commit()
    }
}