converted inventory systems into a module

src/inventory/drop_system.rs

@@ -0,0 +1,68 @@
+use super::{
+    gamelog, EquipmentChanged, InBackpack, MagicItem, MasterDungeonMap, Name, ObfuscatedName, Position, Wand,
+    WantsToDropItem,
+};
+use crate::gui::obfuscate_name;
+use specs::prelude::*;
+
+pub struct ItemDropSystem {}
+
+impl<'a> System<'a> for ItemDropSystem {
+    #[allow(clippy::type_complexity)]
+    type SystemData = (
+        ReadExpect<'a, Entity>,
+        Entities<'a>,
+        WriteStorage<'a, WantsToDropItem>,
+        ReadStorage<'a, Name>,
+        WriteStorage<'a, Position>,
+        WriteStorage<'a, InBackpack>,
+        WriteStorage<'a, EquipmentChanged>,
+        ReadStorage<'a, MagicItem>,
+        ReadStorage<'a, ObfuscatedName>,
+        ReadExpect<'a, MasterDungeonMap>,
+        ReadStorage<'a, Wand>,
+    );
+
+    fn run(&mut self, data: Self::SystemData) {
+        let (
+            player_entity,
+            entities,
+            mut wants_drop,
+            names,
+            mut positions,
+            mut backpack,
+            mut equipment_changed,
+            magic_items,
+            obfuscated_names,
+            dm,
+            wands,
+        ) = data;
+
+        for (entity, to_drop) in (&entities, &wants_drop).join() {
+            equipment_changed.insert(entity, EquipmentChanged {}).expect("Unable to insert EquipmentChanged.");
+            let mut dropper_pos: Position = Position { x: 0, y: 0 };
+            {
+                let dropped_pos = positions.get(entity).unwrap();
+                dropper_pos.x = dropped_pos.x;
+                dropper_pos.y = dropped_pos.y;
+            }
+            positions
+                .insert(to_drop.item, Position { x: dropper_pos.x, y: dropper_pos.y })
+                .expect("Failed to insert position.");
+            backpack.remove(to_drop.item);
+
+            if entity == *player_entity {
+                gamelog::Logger::new()
+                    .append("You drop the")
+                    .item_name_n(format!(
+                        "{}",
+                        obfuscate_name(to_drop.item, &names, &magic_items, &obfuscated_names, &dm, Some(&wands)).0
+                    ))
+                    .period()
+                    .log();
+            }
+        }
+
+        wants_drop.clear();
+    }
+}