import AppKit
import SwiftUI

/// Musubi design tokens. Source of truth: design/tokens.json and docs/03-design.md.
public enum Theme {
    public enum Color {
        public static let sumi    = adaptive(dark: 0x14151B, light: 0xF4F4F6)   // background
        public static let kasumi  = adaptive(dark: 0x1E2029, light: 0xFFFFFF)   // surface
        public static let usuzumi = adaptive(dark: 0x2B2E3A, light: 0xDADBE2)   // lines
        public static let washi   = adaptive(dark: 0xECE9E2, light: 0x16171D)   // text
        public static let nezumi  = adaptive(dark: 0x8E8C96, light: 0x6A6974)   // muted text
        public static let ai      = adaptive(dark: 0x8A99F2, light: 0x4F63D9)   // the one brand accent

        // Status colours – only for states, never decoration.
        public static let shu     = SwiftUI.Color(hex: 0xE5484D)  // tally PGM, talk active
        public static let moegi   = SwiftUI.Color(hex: 0x3DBE7A)  // tally preview, connection ok
        public static let kohaku  = SwiftUI.Color(hex: 0xE8A23A)  // warning
    }

    public enum Radius { public static let card: CGFloat = 12, button: CGFloat = 8, chip: CGFloat = 6 }
    public enum Space  { public static let unit: CGFloat = 8, card: CGFloat = 16 }
    public enum Stroke { public static let line: CGFloat = 1, cord: CGFloat = 2, knot: CGFloat = 6 }

    public enum Font {
        public static let title   = SwiftUI.Font.system(.title3, weight: .semibold)
        public static let body    = SwiftUI.Font.system(.body)
        public static let caption = SwiftUI.Font.system(.caption)
        public static let number  = SwiftUI.Font.system(.body, design: .monospaced).monospacedDigit()
    }

    private static func adaptive(dark: UInt32, light: UInt32) -> SwiftUI.Color {
        SwiftUI.Color(nsColor: NSColor(name: nil) { appearance in
            appearance.bestMatch(from: [.darkAqua, .aqua]) == .darkAqua
                ? NSColor(hex: dark) : NSColor(hex: light)
        })
    }
}

extension SwiftUI.Color {
    public init(hex: UInt32) { self.init(nsColor: NSColor(hex: hex)) }
}

extension NSColor {
    public convenience init(hex: UInt32) {
        self.init(srgbRed: CGFloat((hex >> 16) & 0xFF) / 255,
                  green:   CGFloat((hex >> 8) & 0xFF) / 255,
                  blue:    CGFloat(hex & 0xFF) / 255,
                  alpha:   1)
    }
}