use bevy::prelude::*;
use bevy_mod_imgui::prelude::*;

#[derive(Resource)]
struct ImguiState {
    demo_window_open: bool,
}

fn main() {
    let mut app = App::new();
    app.insert_resource(ClearColor(Color::srgba(0.2, 0.2, 0.2, 1.0)))
        .insert_resource(ImguiState {
            demo_window_open: true,
        })
        .add_plugins(DefaultPlugins)
        .add_systems(Startup, setup)
        .add_plugins(bevy_mod_imgui::ImguiPlugin {
            ini_filename: Some("hello-world.ini".into()),
            font_oversample_h: 2,
            font_oversample_v: 2,
            ..default()
        })
        .add_systems(PostUpdate, imgui_example_ui);

    app.run();
}

fn setup(
    mut commands: Commands,
    mut meshes: ResMut<Assets<Mesh>>,
    mut materials: ResMut<Assets<StandardMaterial>>,
) {
    // plane
    commands.spawn(PbrBundle {
        mesh: meshes.add(Plane3d::default().mesh().size(5.0, 5.0)),
        material: materials.add(Color::srgb(0.3, 0.5, 0.3)),
        ..default()
    });
    // cube
    commands.spawn(PbrBundle {
        mesh: meshes.add(Cuboid::default().mesh()),
        material: materials.add(Color::srgb(0.8, 0.7, 0.6)),
        transform: Transform::from_xyz(0.0, 0.5, 0.0),
        ..default()
    });
    // light
    commands.spawn(PointLightBundle {
        point_light: PointLight {
            shadows_enabled: true,
            ..default()
        },
        transform: Transform::from_xyz(4.0, 8.0, 4.0),
        ..default()
    });
    // camera
    commands.spawn(Camera3dBundle {
        transform: Transform::from_xyz(1.7, 1.7, 2.0).looking_at(Vec3::new(0.0, 0.3, 0.0), Vec3::Y),
        tonemapping: bevy::core_pipeline::tonemapping::Tonemapping::None,
        ..default()
    });
}

fn imgui_example_ui(mut context: NonSendMut<ImguiContext>, mut state: ResMut<ImguiState>) {
    let ui = context.ui();
    let window = ui.window("Hello world");
    window
        .size([300.0, 100.0], imgui::Condition::FirstUseEver)
        .position([0.0, 0.0], imgui::Condition::FirstUseEver)
        .build(|| {
            ui.text("Hello world!");
            ui.text("This...is...bevy_mod_imgui! (from PostUpdate)");
            ui.separator();
            let mouse_pos = ui.io().mouse_pos;
            ui.text(format!(
                "Mouse Position: ({:.1},{:.1})",
                mouse_pos[0], mouse_pos[1]
            ));
        });

    if state.demo_window_open {
        ui.show_demo_window(&mut state.demo_window_open);
    }
}