From 214ac5f56ff3702a83bdb10d9e5f931109795592 Mon Sep 17 00:00:00 2001
From: Thom Bruce <thom@thombruce.com>
Date: Sat, 18 Nov 2023 09:41:00 +0000
Subject: [PATCH 1/5] spawn enemies on a timer

---
 CHANGELOG.md            |  1 +
 src/ships/enemy.rs      | 37 +++++++++++++++++++++++--------------
 src/ships/mod.rs        |  3 ++-
 src/systems/mod.rs      |  2 +-
 src/ui/hud/indicator.rs |  2 ++
 5 files changed, 29 insertions(+), 16 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 085a1e3..ccffb49 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
 - Add game score that increases when player damages or destroys an enemy
+- Spawn timer; enemies will now spawn continuously
 
 ### Changed
 
diff --git a/src/ships/enemy.rs b/src/ships/enemy.rs
index 44acaeb..8613862 100644
--- a/src/ships/enemy.rs
+++ b/src/ships/enemy.rs
@@ -11,6 +11,16 @@ use super::{
     ship::{ship_rotation, ship_thrust, Health, Ship},
 };
 
+pub struct SpawnTimerPlugin;
+impl Plugin for SpawnTimerPlugin {
+    fn build(&self, app: &mut App) {
+        app.insert_resource(SpawnTimer(Timer::from_seconds(6.0, TimerMode::Repeating)));
+    }
+}
+
+#[derive(Resource)]
+pub struct SpawnTimer(pub Timer);
+
 /// Enemy component
 #[derive(Component)]
 pub struct Enemy;
@@ -69,19 +79,17 @@ pub struct Adversaries(pub Vec<DamagedBy>);
 //       retrieval/use at a later time.
 
 /// The setup function
-pub(crate) fn spawn_enemies(mut commands: Commands, sprites: Res<SpriteAssets>) {
-    // Spawns enemy ships
-    for (_i, pos) in [
-        (250.0 as f32, 250.0 as f32),
-        (-250.0 as f32, -250.0 as f32),
-        (-25000.0 as f32, 0.0 as f32),
-        (25000.0 as f32, 0.0 as f32),
-        (0.0 as f32, 25000.0 as f32),
-        (0.0 as f32, -25000.0 as f32),
-    ]
-    .iter()
-    .enumerate()
-    {
+pub(crate) fn spawn_enemies(
+    time: Res<Time>,
+    mut commands: Commands,
+    sprites: Res<SpriteAssets>,
+    mut spawn_timer: ResMut<SpawnTimer>,
+) {
+    // tick the timer
+    spawn_timer.0.tick(time.delta());
+
+    if spawn_timer.0.finished() {
+        // Spawns enemy ships
         commands.spawn((
             Enemy,
             Ship {
@@ -95,7 +103,8 @@ pub(crate) fn spawn_enemies(mut commands: Commands, sprites: Res<SpriteAssets>)
             SpriteBundle {
                 texture: sprites.enemy_ship.clone(),
                 transform: Transform {
-                    translation: Vec3::new(pos.0, pos.1, 100.0),
+                    // TODO: Randomise spawn location
+                    translation: Vec3::new(25_000.0, 5_000.0, 100.0),
                     scale: Vec3::splat(0.5),
                     ..default()
                 },
diff --git a/src/ships/mod.rs b/src/ships/mod.rs
index 4b67cb3..623eaad 100644
--- a/src/ships/mod.rs
+++ b/src/ships/mod.rs
@@ -7,7 +7,7 @@ pub mod enemy;
 pub mod player;
 pub mod ship;
 
-use self::player::PlayerPlugin;
+use self::{enemy::SpawnTimerPlugin, player::PlayerPlugin};
 
 pub struct ShipsPlugin;
 impl Plugin for ShipsPlugin {
@@ -15,6 +15,7 @@ impl Plugin for ShipsPlugin {
         app.add_plugins((
             RapierPhysicsPlugin::<NoUserData>::pixels_per_meter(1.0),
             PlayerPlugin,
+            SpawnTimerPlugin,
         ));
     }
 }
diff --git a/src/systems/mod.rs b/src/systems/mod.rs
index 8c01e52..77eab74 100644
--- a/src/systems/mod.rs
+++ b/src/systems/mod.rs
@@ -74,7 +74,6 @@ impl Plugin for SystemsPlugin {
                 pause::setup_pause_systems,
                 ships::configure_physics_engine,
                 hud::spawn_hud,
-                enemy::spawn_enemies,
                 player::spawn_player,
                 // Planetary system spawning, chained
                 (
@@ -180,6 +179,7 @@ impl Plugin for SystemsPlugin {
                 effects::animate::animate_sprite,
                 astronomy::orbit::orbitable_update_system,
                 astronomy::orbit::orbital_positioning_system,
+                enemy::spawn_enemies,
                 ship::bullet_timers_system,
                 dynamic_orbit::dynamic_orbital_positioning_system,
                 hud::indicator::indicators_system,
diff --git a/src/ui/hud/indicator.rs b/src/ui/hud/indicator.rs
index 299cd52..a499a88 100644
--- a/src/ui/hud/indicator.rs
+++ b/src/ui/hud/indicator.rs
@@ -35,6 +35,8 @@ pub(crate) fn spawn_indicators(
             Bounds {},
         ))
         .with_children(|parent| {
+            // TODO: Spawn indicators when new enemies spawn
+            // TODO: Spawn indicators when in range, despawn when out of range
             for (entity, indicated) in entities_query.iter() {
                 parent.spawn((
                     ImageBundle {

From 5dd1e5527fe16b7b5a3845d5ed0a5c9c0ab1c8cd Mon Sep 17 00:00:00 2001
From: Thom Bruce <thom@thombruce.com>
Date: Sat, 18 Nov 2023 14:43:26 +0000
Subject: [PATCH 2/5] spawn indicators on update

---
 CHANGELOG.md            |  1 +
 src/systems/mod.rs      |  1 +
 src/ui/hud/indicator.rs | 51 +++++++++++++++++++++++++----------------
 3 files changed, 33 insertions(+), 20 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index ccffb49..584e2d9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,6 +16,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Decrease static orbit scale (planets are now closer)
 - Clamp orbit distance (prevents Moon orbiting inside of Earth sprite)
+- Indicators spawn on update allowing new entities to be pointed to
 
 ## [0.0.25] - 2023-11-17
 
diff --git a/src/systems/mod.rs b/src/systems/mod.rs
index 77eab74..4387865 100644
--- a/src/systems/mod.rs
+++ b/src/systems/mod.rs
@@ -182,6 +182,7 @@ impl Plugin for SystemsPlugin {
                 enemy::spawn_enemies,
                 ship::bullet_timers_system,
                 dynamic_orbit::dynamic_orbital_positioning_system,
+                hud::indicator::spawn_indicator_children.before(hud::indicator::indicators_system),
                 hud::indicator::indicators_system,
                 hud::speedometer::hud_speedometer,
                 hud::health::hud_health,
diff --git a/src/ui/hud/indicator.rs b/src/ui/hud/indicator.rs
index a499a88..3fc33bd 100644
--- a/src/ui/hud/indicator.rs
+++ b/src/ui/hud/indicator.rs
@@ -15,29 +15,39 @@ pub struct Indicator {
 #[derive(Component, Clone, Debug)]
 pub struct Bounds {}
 
-pub(crate) fn spawn_indicators(
+#[derive(Component, Clone, Debug)]
+pub struct IndicatorsContainer;
+
+pub(crate) fn spawn_indicators(mut commands: Commands) {
+    commands.spawn((
+        NodeBundle {
+            style: Style {
+                position_type: PositionType::Absolute,
+                width: Val::Percent(100.0),
+                height: Val::Percent(100.0),
+                ..default()
+            },
+            ..default()
+        },
+        Name::new("Indicators"),
+        Bounds {},
+        IndicatorsContainer,
+    ));
+}
+
+pub(crate) fn spawn_indicator_children(
     mut commands: Commands,
     asset_server: Res<AssetServer>,
     entities_query: Query<(Entity, &Indicated)>,
+    parent: Query<Entity, With<IndicatorsContainer>>,
+    indicators: Query<&Indicator>,
 ) {
-    commands
-        .spawn((
-            NodeBundle {
-                style: Style {
-                    position_type: PositionType::Absolute,
-                    width: Val::Percent(100.0),
-                    height: Val::Percent(100.0),
-                    ..default()
-                },
-                ..default()
-            },
-            Name::new("Indicators"),
-            Bounds {},
-        ))
-        .with_children(|parent| {
-            // TODO: Spawn indicators when new enemies spawn
-            // TODO: Spawn indicators when in range, despawn when out of range
-            for (entity, indicated) in entities_query.iter() {
+    let parent = parent.get_single().unwrap();
+
+    commands.entity(parent).with_children(|parent| {
+        // TODO: Spawn indicators when in range, despawn when out of range
+        for (entity, indicated) in entities_query.iter() {
+            if !indicators.iter().any(|i| i.entity == entity) {
                 parent.spawn((
                     ImageBundle {
                         image: UiImage::new(asset_server.load("images/grey_arrowUpWhite.png")),
@@ -53,7 +63,8 @@ pub(crate) fn spawn_indicators(
                     Indicator { entity: entity },
                 ));
             }
-        });
+        }
+    });
 }
 
 pub(crate) fn indicators_system(

From c7e446c69f16649b8438aa7a0f6c7034dff0b111 Mon Sep 17 00:00:00 2001
From: Thom Bruce <thom@thombruce.com>
Date: Sat, 18 Nov 2023 15:18:38 +0000
Subject: [PATCH 3/5] spawn enemies at random distance and direction from
 player

---
 CHANGELOG.md       |  1 +
 src/ships/enemy.rs | 16 ++++++++++++++--
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 584e2d9..7f6554b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
+- Spawn enemies at random distance and direction from player
 - Decrease static orbit scale (planets are now closer)
 - Clamp orbit distance (prevents Moon orbiting inside of Earth sprite)
 - Indicators spawn on update allowing new entities to be pointed to
diff --git a/src/ships/enemy.rs b/src/ships/enemy.rs
index 8613862..f4d493e 100644
--- a/src/ships/enemy.rs
+++ b/src/ships/enemy.rs
@@ -1,5 +1,6 @@
 use bevy::prelude::*;
 use bevy_rapier2d::prelude::*;
+use rand::Rng;
 
 use crate::core::resources::assets::SpriteAssets;
 use crate::systems::events::BulletSpawnEvent;
@@ -84,11 +85,23 @@ pub(crate) fn spawn_enemies(
     mut commands: Commands,
     sprites: Res<SpriteAssets>,
     mut spawn_timer: ResMut<SpawnTimer>,
+    player_position: Query<&Transform, With<Player>>,
 ) {
     // tick the timer
     spawn_timer.0.tick(time.delta());
 
     if spawn_timer.0.finished() {
+        let Ok(from) = player_position.get_single() else {
+            return;
+        };
+
+        let random_x = rand::thread_rng().gen_range(-25_000.0..25_000.0);
+        let random_y = rand::thread_rng().gen_range(-25_000.0..25_000.0);
+
+        let new_pos = (from.translation.truncate()
+            + Vec2::new(random_x, random_y).clamp_length_min(5_000.0))
+        .extend(100.0);
+
         // Spawns enemy ships
         commands.spawn((
             Enemy,
@@ -103,8 +116,7 @@ pub(crate) fn spawn_enemies(
             SpriteBundle {
                 texture: sprites.enemy_ship.clone(),
                 transform: Transform {
-                    // TODO: Randomise spawn location
-                    translation: Vec3::new(25_000.0, 5_000.0, 100.0),
+                    translation: new_pos,
                     scale: Vec3::splat(0.5),
                     ..default()
                 },

From 14a15ef71b3eb72dfff20f50df707497a28bc86d Mon Sep 17 00:00:00 2001
From: Thom Bruce <thom@thombruce.com>
Date: Sat, 18 Nov 2023 15:22:23 +0000
Subject: [PATCH 4/5] limit total concurrent enemies to 10

---
 CHANGELOG.md       | 1 +
 src/ships/enemy.rs | 3 ++-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7f6554b..b3c663e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -15,6 +15,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
 
 - Spawn enemies at random distance and direction from player
+- Limit total concurrent enemies to 10
 - Decrease static orbit scale (planets are now closer)
 - Clamp orbit distance (prevents Moon orbiting inside of Earth sprite)
 - Indicators spawn on update allowing new entities to be pointed to
diff --git a/src/ships/enemy.rs b/src/ships/enemy.rs
index f4d493e..a6a6188 100644
--- a/src/ships/enemy.rs
+++ b/src/ships/enemy.rs
@@ -86,11 +86,12 @@ pub(crate) fn spawn_enemies(
     sprites: Res<SpriteAssets>,
     mut spawn_timer: ResMut<SpawnTimer>,
     player_position: Query<&Transform, With<Player>>,
+    enemies: Query<&Enemy>,
 ) {
     // tick the timer
     spawn_timer.0.tick(time.delta());
 
-    if spawn_timer.0.finished() {
+    if spawn_timer.0.finished() && enemies.iter().count() < 10 {
         let Ok(from) = player_position.get_single() else {
             return;
         };

From ef02de4149c5e311d2848c5510d8afcfe1f1e407 Mon Sep 17 00:00:00 2001
From: Thom Bruce <thom@thombruce.com>
Date: Sat, 18 Nov 2023 15:30:05 +0000
Subject: [PATCH 5/5] fix bug preventing player death

---
 src/ships/ship.rs | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/ships/ship.rs b/src/ships/ship.rs
index c493b63..565514f 100644
--- a/src/ships/ship.rs
+++ b/src/ships/ship.rs
@@ -93,6 +93,11 @@ pub(crate) fn ship_death_handling(
     };
 
     for event in death_events.read() {
+        if event.entity == player {
+            commands.entity(event.entity).despawn();
+            continue;
+        }
+
         let Ok(adversaries) = adversaries.get(event.entity) else {
             return;
         };
@@ -111,9 +116,7 @@ pub(crate) fn ship_death_handling(
 
         // If the destroyed ship is not the player, award XP to the player equal to
         // 10x the damage the player has dealt to the ship.
-        if event.entity != player {
-            score.0 += 10 * player_dealt_damage; // TODO: Make proportionate to player-dealt damage relative to MaxHealth
-        }
+        score.0 += 10 * player_dealt_damage; // TODO: Make proportionate to player-dealt damage relative to MaxHealth
 
         commands.entity(event.entity).despawn();
     }