import Foundation
import Metal

public class CloudySkyRenderable: ConfiguredQuadRenderable<CloudySkyRenderable.Config> {
    public struct Config: QuadRenderConfiguration {
        // matches CloudySky_Uniforms
        var resolution: ADVector2
        var time: ADFloat

        var cloudscale: ADFloat
        var speed: ADFloat
        var clouddark: ADFloat
        var cloudlight: ADFloat
        var cloudcover: ADFloat
        var cloudalpha: ADFloat
        var skytint: ADFloat

        var skycolour1: ADVector3
        var skycolour2: ADVector3

        public init(
            resolution: ADVector2 = .ones,
            time: ADFloat = .zero,
            cloudscale: ADFloat = 1.1,
            speed: ADFloat = 0.03,
            clouddark: ADFloat = 0.5,
            cloudlight: ADFloat = 0.3,
            cloudcover: ADFloat = 0.2,
            cloudalpha: ADFloat = 8.0,
            skytint: ADFloat = 0.5,
            skycolour1: ADVector3 = .init(x: 0.2, y: 0.4, z: 0.6),
            skycolour2: ADVector3 = .init(x: 0.4, y: 0.7, z: 1.0)
        ) {
            self.resolution = resolution
            self.time = time
            self.cloudscale = cloudscale
            self.speed = speed
            self.clouddark = clouddark
            self.cloudlight = cloudlight
            self.cloudcover = cloudcover
            self.cloudalpha = cloudalpha
            self.skytint = skytint
            self.skycolour1 = skycolour1
            self.skycolour2 = skycolour2
        }

        public static var defaultConfiguration: Config {
            return Config()
        }
    }

    /// Name of the Metal fragment function in your `.metal` library
    override public var fragmentShaderName: String {
        return "clouds_fragment"
    }

    /// Hook to set up any extra state before drawing;
    /// here all your `Config` fields are bound automatically.
    override public var configureAction: ConfigureAction {
        return { encoder in
            super.configureAction(encoder)
            // if you ever need to tweak bindings manually, do it here
        }
    }
}