use bevy::prelude::*;

const FALL_SPEED: f32 = 300.0; // Falling speed
const DIVE_SPEED: f32 = 700.0; // Falling speed sped up
const HORIZONTAL_SPEED: f32 = 300.0; // Lateral movement speed

// The player
#[derive(Component)]
pub struct Player;

// Speed of the player
#[derive(Component)]
pub struct Velocity(Vec2);

// Spawn entity player
fn spawn_player(mut commands: Commands) {
    commands.spawn((
        Player,
        Velocity(Vec2::ZERO),
        Sprite::from_color(Color::srgb(1.0, 1.0, 1.0), Vec2::new(20.0, 40.0)),
        Transform::from_xyz(0.0, 0.0, 1.0),
    ));
}

// Input + movement system for the player
pub(crate) fn move_player(
    input: Res<ButtonInput<KeyCode>>,
    time: Res<Time>,
    mut player: Query<(&mut Velocity, &mut Transform), With<Player>>,
) {
    // If matching entity
    let Ok((mut velocity, mut transform)) = player.single_mut() else {
        return;
    };

    // Change then horizontal direction regardless the input
    let direction = if input.pressed(KeyCode::KeyA) {
        -1.0
    } else if input.pressed(KeyCode::KeyD) {
        1.0
    } else {
        0.0
    };

    velocity.0 = Vec2::new(
        direction * HORIZONTAL_SPEED,
        -if input.pressed(KeyCode::KeyS) {
            DIVE_SPEED
        } else {
            FALL_SPEED
        },
    );

    transform.translation += velocity.0.extend(0.0) * time.delta_secs();
}

pub struct PlayerPlugin;

impl Plugin for PlayerPlugin {
    fn build(&self, app: &mut App) {
        app.add_systems(Startup, spawn_player)
            .add_systems(Update, move_player);
    }
}