//! A Bevy app that can be used as an integration test target.
//! It displays a button that must be clicked. The button is placed at a random position and
//! moves every 5 seconds.
//!
//! Run with the `bevy_remote` and `bevy_feathers` feature enabled:
//! ```bash
//! cargo run --example app_under_test --features="bevy_remote bevy_feathers"
//! ```
//! This example can be paired with the `integration_test` example, which will run an integration
//! test on this app.

use bevy::{
    feathers::{
        controls::FeathersButton, dark_theme::create_dark_theme, display::caption, theme::UiTheme,
        FeathersPlugins,
    },
    prelude::*,
    remote::{http::RemoteHttpPlugin, RemotePlugin},
    time::common_conditions::on_timer,
    ui::UiGlobalTransform,
};
use chacha20::ChaCha8Rng;
use rand::{RngExt, SeedableRng};

fn main() {
    App::new()
        .add_plugins((DefaultPlugins, FeathersPlugins))
        // To make the app available for integration testing, we add these
        // remote plugins to expose API’s for a testing framework to call.
        .add_plugins(RemotePlugin::default())
        .add_plugins(RemoteHttpPlugin::default())
        .insert_resource(UiTheme(create_dark_theme()))
        .insert_resource(SeededRng(ChaCha8Rng::seed_from_u64(19878367467712)))
        .add_systems(Startup, setup)
        .add_systems(
            Update,
            (
                move_button.run_if(on_timer(std::time::Duration::from_secs(5))),
                log_button_position,
            ),
        )
        .run();
}

#[derive(Resource)]
struct SeededRng(ChaCha8Rng);

fn on_button_click(_click: On<PointerClick>, mut exit: MessageWriter<AppExit>) {
    info!("Button pressed!");
    exit.write(AppExit::Success);
}

fn log_button_position(
    transform: Single<&UiGlobalTransform, (With<FeathersButton>, Changed<UiGlobalTransform>)>,
) {
    info!(
        "Button at physical ({}, {})",
        transform.translation.x, transform.translation.y
    );
}

fn random_position(rng: &mut ChaCha8Rng) -> (f32, f32) {
    let left_pct = rng.random_range(0.0..=60.0);
    let top_pct = rng.random_range(0.0..=60.0);
    (left_pct, top_pct)
}

fn move_button(
    mut rng: ResMut<SeededRng>,
    mut button_query: Query<&mut Node, With<FeathersButton>>,
) {
    let (left_pct, top_pct) = random_position(&mut rng.0);
    for mut node in &mut button_query {
        node.left = percent(left_pct);
        node.top = percent(top_pct);
    }
}

fn setup(mut commands: Commands, mut rng: ResMut<SeededRng>) {
    let (left_pct, top_pct) = random_position(&mut rng.0);
    commands.spawn(Camera2d);
    commands.spawn_scene(bsn! {
        Node {
            width: percent(100),
            height: percent(100),
        }
        Children [
            @FeathersButton {
                @caption: bsn! { @caption("Button") }
            }
            Node {
                width: px(150),
                height: px(65),
                border: UiRect::all(px(5)),
                left: percent(left_pct),
                top: percent(top_pct),
            }
            BorderColor::all(Color::WHITE)
            on(on_button_click)
        ]
    });
}