gui, inventory, symmetrical shadowcasting, bugfixes

src/inventory_system.rs

@@ -0,0 +1,68 @@
+use super::{gamelog::GameLog, CombatStats, InBackpack, Name, Position, Potion, WantsToDrinkPotion, WantsToPickupItem};
+use specs::prelude::*;
+
+pub struct ItemCollectionSystem {}
+
+impl<'a> System<'a> for ItemCollectionSystem {
+    #[allow(clippy::type_complexity)]
+    type SystemData = (
+        ReadExpect<'a, Entity>,
+        WriteExpect<'a, GameLog>,
+        WriteStorage<'a, WantsToPickupItem>,
+        WriteStorage<'a, Position>,
+        ReadStorage<'a, Name>,
+        WriteStorage<'a, InBackpack>,
+    );
+
+    fn run(&mut self, data: Self::SystemData) {
+        let (player_entity, mut gamelog, mut wants_pickup, mut positions, names, mut backpack) = data;
+
+        for pickup in wants_pickup.join() {
+            positions.remove(pickup.item);
+            backpack.insert(pickup.item, InBackpack { owner: pickup.collected_by }).expect("Unable to pickup item.");
+
+            if pickup.collected_by == *player_entity {
+                gamelog.entries.push(format!("You pick up the {}.", names.get(pickup.item).unwrap().name));
+            }
+        }
+
+        wants_pickup.clear();
+    }
+}
+
+pub struct PotionUseSystem {}
+impl<'a> System<'a> for PotionUseSystem {
+    #[allow(clippy::type_complexity)]
+    type SystemData = (
+        ReadExpect<'a, Entity>,
+        WriteExpect<'a, GameLog>,
+        Entities<'a>,
+        WriteStorage<'a, WantsToDrinkPotion>,
+        ReadStorage<'a, Name>,
+        ReadStorage<'a, Potion>,
+        WriteStorage<'a, CombatStats>,
+    );
+
+    fn run(&mut self, data: Self::SystemData) {
+        let (player_entity, mut gamelog, entities, mut wants_drink, names, potions, mut combat_stats) = data;
+
+        for (entity, drink, stats) in (&entities, &wants_drink, &mut combat_stats).join() {
+            let potion = potions.get(drink.potion);
+            match potion {
+                None => {}
+                Some(potion) => {
+                    stats.hp = i32::min(stats.max_hp, stats.hp + potion.heal_amount);
+                    if entity == *player_entity {
+                        gamelog.entries.push(format!(
+                            "You quaff the {}, and heal {} hp.",
+                            names.get(drink.potion).unwrap().name,
+                            potion.heal_amount
+                        ));
+                    }
+                    entities.delete(drink.potion).expect("Delete failed");
+                }
+            }
+        }
+        wants_drink.clear();
+    }
+}