use bevy::prelude::*;
use bevy::render::render_resource::{AsBindGroup, ShaderRef};
use bevy::pbr::{ExtendedMaterial, MaterialExtension, OpaqueRendererMethod};

pub struct ShadingPlugin;
impl Plugin for ShadingPlugin {
    fn build(&self, app: &mut App) {
        app.add_plugins(MaterialPlugin::<JupitersRing>::default());
        app.add_plugins(MaterialPlugin::<ExtendedMaterial<StandardMaterial, AsteroidSurface, >>::default());
    }
}

#[derive(Asset, TypePath, AsBindGroup, Debug, Clone)]
pub struct JupitersRing {
    pub alpha_mode: AlphaMode,
    #[uniform(0)]
    pub ring_radius: f32,
    #[uniform(1)]
    pub jupiter_radius: f32,
}

impl Material for JupitersRing {
    fn fragment_shader() -> ShaderRef {
        "shaders/jupiters_rings.wgsl".into()
    }
    fn alpha_mode(&self) -> AlphaMode {
        self.alpha_mode
    }
}


#[derive(Asset, Reflect, AsBindGroup, Debug, Clone)]
pub struct AsteroidSurface {
    #[uniform(100)]
    quantize_steps: u32
}

impl MaterialExtension for AsteroidSurface {
    fn fragment_shader() -> ShaderRef {
        "shaders/material_asteroid.wgsl".into()
    }
    fn deferred_fragment_shader() -> ShaderRef {
        "shaders/material_asteroid.wgsl".into()
    }
}

impl AsteroidSurface {
    pub fn material() -> ExtendedMaterial<StandardMaterial, AsteroidSurface> {
        ExtendedMaterial {
            base: StandardMaterial {
                base_color: Color::rgb(0.29, 0.255, 0.208),
                perceptual_roughness: 1.0,
                opaque_render_method: OpaqueRendererMethod::Auto,
                ..default()
            },
            extension: Self::default(),
        }
    }
}
impl Default for AsteroidSurface {
    fn default() -> Self {
        Self {
            quantize_steps: 3,
        }
    }
}