// The menu bar's own glyph — Claude's asterisk over a coat's collar and
// shoulders. Drawn here rather than scaled down from the app icon, which is
// what the menu bar used to show: at 18pt the app icon's three coats, lapels
// and pockets collapse into a smudge, and its colours fight the menu bar
// instead of following it.
//
// Returned as a *template* image, which is what makes it track the system
// theme with no code of ours involved. A template carries only an alpha
// channel; macOS supplies the colour — dark on a light menu bar, light on a
// dark one, inverted again while the menu is open — and re-tints it on the fly
// when the theme switches. That also dictates the drawing: no fills of our
// own, and any internal detail has to be a hole punched through the alpha.
import AppKit

enum MenuBarIcon {
    // Six rays rather than the app icon's eight. At 18pt an eight-ray asterisk
    // has under a pixel of gap between arms, so they merge into a blob; six
    // resolve as separate arms. Lengths stay slightly uneven, as on the app
    // icon, so it doesn't read as a snowflake.
    private static let rayCount = 6
    private static let rayLengths: [CGFloat] = [1.0, 0.88, 0.97, 0.86, 1.0, 0.9]
    private static let rayRadius: CGFloat = 22
    private static let rayWidth: CGFloat = 7.2
    private static let asteriskCentre = NSPoint(x: 50, y: 28)

    static func image(pointSize: CGFloat = 18) -> NSImage {
        let image = NSImage(size: NSSize(width: pointSize, height: pointSize))
        image.lockFocusFlipped(false)

        // Authored y-down like the app icon; flip once rather than mirroring
        // every coordinate.
        let flip = NSAffineTransform()
        flip.translateX(by: 0, yBy: pointSize)
        flip.scaleX(by: pointSize / 100, yBy: -pointSize / 100)
        flip.concat()

        NSColor.black.setStroke()
        asterisk().stroke()
        NSColor.black.setFill()
        coat().fill()

        image.unlockFocus()
        image.isTemplate = true
        return image
    }

    private static func asterisk() -> NSBezierPath {
        let path = NSBezierPath()
        for index in 0..<rayCount {
            let angle = (CGFloat(index) * 360 / CGFloat(rayCount) + 8) * .pi / 180
            let radius = rayRadius * rayLengths[index]
            path.move(to: asteriskCentre)
            path.line(to: NSPoint(x: asteriskCentre.x + radius * cos(angle),
                                  y: asteriskCentre.y + radius * sin(angle)))
        }
        path.lineWidth = rayWidth
        path.lineCapStyle = .round
        return path
    }

    // Read along the top edge from one side to the other: shoulder, a slight
    // tilt up, a flat collar top, the valley at the neck, then the mirror of
    // that. Square sides and a flat hem below.
    //
    // The flat sections are 13 units wide because anything narrower stops
    // reading as flat at this size and just looks like part of the slope —
    // 13 units is roughly 2.3px at 18pt, about the floor for that.
    private static func coat() -> NSBezierPath {
        let path = NSBezierPath()
        path.move(to: NSPoint(x: 15, y: 72))   // left shoulder
        path.line(to: NSPoint(x: 27, y: 60))   // slight tilt up
        path.line(to: NSPoint(x: 40, y: 60))   // flat collar top
        path.line(to: NSPoint(x: 50, y: 78))   // valley at the neck
        path.line(to: NSPoint(x: 60, y: 60))
        path.line(to: NSPoint(x: 73, y: 60))
        path.line(to: NSPoint(x: 85, y: 72))   // right shoulder
        path.line(to: NSPoint(x: 85, y: 94))
        path.line(to: NSPoint(x: 15, y: 94))
        path.close()
        return path
    }
}