import AppKit
import SwiftUI

// MARK: - Centralized Theme Manager
class ThemeManager {
    static let shared = ThemeManager()
    
    private init() {}
    
    // MARK: - System-Aware Colors (automatic light/dark adaptation)
    
    /// Background colors for containers (GLASS EFFECT zoals stash)
    var containerBackground: NSColor {
        // NIEUW: Glass effect achtergrond zoals stash window
        // Gebruik transparante achtergrond zodat visual effect view erdoor kan
        return NSColor.clear
    }
    
    /// Glass effect background for visual effect views
    var glassEffectMaterial: NSVisualEffectView.Material {
        return .hudWindow // Exact hetzelfde als stash window
    }
    
    /// Glass effect blending mode
    var glassEffectBlending: NSVisualEffectView.BlendingMode {
        return .behindWindow // Exact hetzelfde als stash window
    }
    
    /// Glass effect alpha
    var glassEffectAlpha: CGFloat {
        return 0.95 // Exact hetzelfde als stash window
    }
    
    /// Background colors for secondary containers
    var secondaryContainerBackground: NSColor {
        if NSApp.effectiveAppearance.name == NSAppearance.Name.darkAqua {
            return NSColor(white: 0.42, alpha: 0.90) // Dark mode: iets lichter
        } else {
            return NSColor(white: 0.98, alpha: 0.90) // Light mode: bijna wit
        }
    }
    
    /// Button and icon colors (adaptive)
    var buttonTintColor: NSColor {
        if NSApp.effectiveAppearance.name == NSAppearance.Name.darkAqua {
            return NSColor(white: 0.95, alpha: 1.0) // Dark mode: wit
        } else {
            return NSColor(white: 0.25, alpha: 1.0) // Light mode: donkergrijs
        }
    }
    
    /// Text colors (adaptive)
    var primaryTextColor: NSColor {
        if NSApp.effectiveAppearance.name == NSAppearance.Name.darkAqua {
            return NSColor.white // Dark mode: wit
        } else {
            return NSColor.black // Light mode: zwart
        }
    }
    
    var secondaryTextColor: NSColor {
        if NSApp.effectiveAppearance.name == NSAppearance.Name.darkAqua {
            return NSColor(white: 0.7, alpha: 1.0) // Dark mode: grijs
        } else {
            return NSColor(white: 0.4, alpha: 1.0) // Light mode: donkergrijs
        }
    }
    
    /// Filename label text color (adaptive with opacity)
    var filenameLabelTextColor: NSColor {
        if NSApp.effectiveAppearance.name == NSAppearance.Name.darkAqua {
            return NSColor(white: 0.7, alpha: 1.0) // Dark mode: lichtgrijs
        } else {
            return NSColor(white: 0.1, alpha: 1.0) // Light mode: veel donkerder voor betere zichtbaarheid
        }
    }
    
    /// Grid cell icon background (adaptive)
    var gridCellIconBackground: NSColor {
        if NSApp.effectiveAppearance.name == NSAppearance.Name.darkAqua {
            return NSColor.white.withAlphaComponent(0.25) // Dark mode
        } else {
            return NSColor.black.withAlphaComponent(0.25) // Light mode
        }
    }
    
    /// Grid cell text color with hover effect
    func gridCellTextColor(isHovered: Bool) -> NSColor {
        if NSApp.effectiveAppearance.name == NSAppearance.Name.darkAqua {
            return isHovered ? NSColor.white : NSColor.white.withAlphaComponent(0.1)
        } else {
            return isHovered ? NSColor.black : NSColor.black.withAlphaComponent(0.1)
        }
    }
    
    // MARK: - Shadow Configuration (adaptive)
    var shadowColor: NSColor {
        if NSApp.effectiveAppearance.name == NSAppearance.Name.darkAqua {
            return NSColor.black // Dark mode: black shadows
        } else {
            return NSColor.black.withAlphaComponent(0.3) // Light mode: lighter shadows
        }
    }
    
    var shadowOpacity: Float {
        if NSApp.effectiveAppearance.name == NSAppearance.Name.darkAqua {
            return 0.50 // Dark mode: stronger shadows
        } else {
            return 0.25 // Light mode: subtle shadows
        }
    }
    
    // MARK: - Utility Methods
    
    /// Check if currently in dark mode
    var isDarkMode: Bool {
        return NSApp.effectiveAppearance.name == NSAppearance.Name.darkAqua
    }
    
    /// Debug function to print current theme info
    func printCurrentTheme() {
        let mode = isDarkMode ? "DARK" : "LIGHT"
        print("🎨 THEME DEBUG: Current mode = \(mode)")
        print("🎨 THEME DEBUG: Container background = GLASS EFFECT (\(glassEffectMaterial.rawValue))")
        print("🎨 THEME DEBUG: Glass effect alpha = \(glassEffectAlpha)")
        print("🎨 THEME DEBUG: Button tint = \(buttonTintColor)")
        print("🎨 THEME DEBUG: Primary text = \(primaryTextColor)")
        print("🎨 THEME DEBUG: Shadow opacity = \(shadowOpacity)")
    }
    
    /// Get hover color for buttons
    var buttonHoverColor: NSColor {
        if isDarkMode {
            return NSColor.white
        } else {
            return NSColor.black
        }
    }
    
    /// Get original button color (for hover restoration)
    var buttonOriginalColor: NSColor {
        return buttonTintColor
    }
    
    // MARK: - Notification for Theme Changes
    func observeThemeChanges(callback: @escaping () -> Void) {
        // Observer voor system appearance changes
        DistributedNotificationCenter.default.addObserver(
            forName: NSNotification.Name("AppleInterfaceThemeChangedNotification"),
            object: nil,
            queue: .main
        ) { _ in
            print("🎨 THEME: System theme changed - notifying observers")
            callback()
        }
    }
}

// MARK: - SwiftUI Color Extensions
extension Color {
    static var adaptiveContainerBackground: Color {
        Color(ThemeManager.shared.containerBackground)
    }
    
    static var adaptiveSecondaryBackground: Color {
        Color(ThemeManager.shared.secondaryContainerBackground)
    }
    
    static var adaptivePrimaryText: Color {
        Color(ThemeManager.shared.primaryTextColor)
    }
    
    static var adaptiveSecondaryText: Color {
        Color(ThemeManager.shared.secondaryTextColor)
    }
}