step 5.3: done

tests/integration/inventory.test.js

@@ -12,7 +12,7 @@ describe('inventoryService', () => {
   before(async () => {
     await setup();
     db = require('../../src/db').getDb();
-    ({ listInventory, equipItem, unequipItem } = require('../../src/services/inventoryService'));
+    ({ listInventory, equipItem, unequipItem, useConsumable } = require('../../src/services/inventoryService'));
     ({ createCharacter } = require('../../src/services/characterService'));
   });
 
@@ -163,4 +163,111 @@ describe('inventoryService', () => {
     assert.ok(result.derived.maxHp > baseMaxHp,
       `maxHp should increase with vit bonus (was ${baseMaxHp}, now ${result.derived.maxHp})`);
   });
+
+  it('uses a healing potion and increases HP (capped at maxHp)', () => {
+    const id = makeHero({ level: 1, str: 8, agi: 4, int: 2, vit: 8 });
+    // Grant 3 Minor Healing Potions (item 14, heal:50)
+    grantItem(id, 14, 3);
+
+    // Set HP to 60 (out of ~145 maxHp for warrior with vit=8: 50+80+5=135)
+    db.prepare('UPDATE characters SET hp_current = 60 WHERE id = ?').run(id);
+
+    const before = listInventory(id);
+    const beforeHp = db.prepare('SELECT hp_current FROM characters WHERE id = ?').get(id).hp_current;
+    const maxHp = before.derived.maxHp;
+
+    // Use one potion: should heal to min(60+50, maxHp)
+    const result = useConsumable(id, 14);
+    const afterHp = db.prepare('SELECT hp_current FROM characters WHERE id = ?').get(id).hp_current;
+
+    assert.equal(afterHp, Math.min(beforeHp + 50, maxHp));
+    // Quantity should be 3 → 2 (still in inventory)
+    const potion = result.items.find((i) => i.itemId === 14);
+    assert.equal(potion.quantity, 2);
+  });
+
+  it('uses an energy tonic and restores energy (capped at 100)', () => {
+    const id = makeHero({ level: 1, str: 8, agi: 4, int: 2, vit: 8 });
+    // Grant 2 Energy Tonics (item 16, energy:25)
+    grantItem(id, 16, 2);
+
+    // Set energy to 40
+    db.prepare('UPDATE characters SET energy = 40 WHERE id = ?').run(id);
+
+    const before = listInventory(id);
+    const beforeEnergy = db.prepare('SELECT energy FROM characters WHERE id = ?').get(id).energy;
+
+    // Use one tonic: should restore to min(40+25, 100) = 65
+    const result = useConsumable(id, 16);
+    const afterEnergy = db.prepare('SELECT energy FROM characters WHERE id = ?').get(id).energy;
+
+    assert.equal(afterEnergy, Math.min(beforeEnergy + 25, 100));
+    // Quantity should be 2 → 1
+    const tonic = result.items.find((i) => i.itemId === 16);
+    assert.equal(tonic.quantity, 1);
+  });
+
+  it('rejects using a non-consumable item', () => {
+    const id = makeHero();
+    grantItem(id, 1); // Rusty Sword (weapon)
+    assert.throws(() => useConsumable(id, 1), (e) => e.code === 'VALIDATION_ERROR');
+  });
+
+  it('rejects using an item not in inventory', () => {
+    const id = makeHero();
+    // Item 14 exists but not granted to this character
+    assert.throws(() => useConsumable(id, 14), (e) => e.code === 'NOT_FOUND');
+  });
+
+  it('removes inventory row when quantity reaches 0 (single-item stack)', () => {
+    const id = makeHero({ level: 1, str: 8, agi: 4, int: 2, vit: 8 });
+    // Grant 1 Greater Healing Potion (item 15, heal:150)
+    grantItem(id, 15, 1);
+
+    // Set HP low
+    db.prepare('UPDATE characters SET hp_current = 20 WHERE id = ?').run(id);
+
+    const before = listInventory(id);
+    assert.equal(before.items.find((i) => i.itemId === 15).quantity, 1);
+
+    useConsumable(id, 15);
+
+    const after = listInventory(id);
+    const potion = after.items.find((i) => i.itemId === 15);
+    assert.equal(potion, undefined, 'consumable row should be removed when quantity hits 0');
+  });
+
+  it('caps heal effect at maxHp', () => {
+    const id = makeHero({ level: 1, str: 8, agi: 4, int: 2, vit: 8 });
+    grantItem(id, 14, 5); // Minor Healing Potion (heal:50)
+
+    // Set HP already at max
+    const before = listInventory(id);
+    const maxHp = before.derived.maxHp;
+    db.prepare('UPDATE characters SET hp_current = ? WHERE id = ?').run(maxHp, id);
+
+    useConsumable(id, 14);
+
+    const after = listInventory(id);
+    const hp = db.prepare('SELECT hp_current FROM characters WHERE id = ?').get(id).hp_current;
+    assert.equal(hp, maxHp, 'HP should not exceed maxHp');
+    // Quantity should decrease
+    assert.equal(after.items.find((i) => i.itemId === 14).quantity, 4);
+  });
+
+  it('caps energy effect at ENERGY_MAX (100)', () => {
+    const id = makeHero({ level: 1, str: 8, agi: 4, int: 2, vit: 8 });
+    grantItem(id, 16, 5); // Energy Tonic (energy:25)
+
+    // Set energy to 90
+    db.prepare('UPDATE characters SET energy = 90 WHERE id = ?').run(id);
+
+    useConsumable(id, 16);
+
+    const after = listInventory(id);
+    const energy = db.prepare('SELECT energy FROM characters WHERE id = ?').get(id).energy;
+    assert.equal(energy, 100, 'Energy should not exceed 100');
+    // Quantity should decrease
+    assert.equal(after.items.find((i) => i.itemId === 16).quantity, 4);
+  });
 });