Emberfall/HANDOFF.md

HANDOFF.md — Session Handoff (OVERWRITE at the end of every phase or when context is getting long)

Read order for a new session: NOTES.md → STATUS.md → this file → then work. If this file disagrees with the code, trust the code and fix this file.

1. Where we are

• Last completed step: 5.4 (inventory UI: tabs, equipment panel, inventory grid, tooltips)
• Next step: 6.1 — Shop: GET /api/shop, POST /api/shop/buy, POST /api/shop/sell
• Updated: 2026-10-20
• Was the last session cut off mid-task? No

2. Verified state (run these first)

Command	Expected
npm install	succeeds
npm run migrate	applies 001–004 and 006 / "nothing to do"
npm test	118 passing, 0 failing (87 unit + 31 integration)

3. What exists now (files that matter)

• src/game/stats.js — calcDerived() is the ONLY derived-stat formula. Also re-exports xpToNext/checkLevelUp.
• src/game/combat.js — resolveCombat(hero, monster, rng); both sides attack each round, faster first.
• src/services/huntService.js — hunt(characterId, zoneId, {rng, now}); ONE transaction; test-injectable.
• src/services/zoneService.js — listZones(characterLevel) → zones with unlocked flag.
• src/services/combatLogService.js — getCombatLog(characterId, limit) → recent fights.
• src/services/characterService.js — createCharacter, getCharacterProfile, getCharacterIdForUser.
• src/services/inventoryService.js — listInventory, equipItem, unequipItem, useConsumable. Uses WeakMap stmt cache.
• src/routes/inventory.js — GET /api/inventory, POST /api/inventory/equip, POST /api/inventory/unequip, POST /api/inventory/use.
• src/utils/time.js — now()/setNow()/resetNow(); never call Date.now() in services.
• src/routes/zones.js — GET /api/zones.
• src/routes/combatLog.js — GET /api/combat-log.
• src/db/migrations/003_content.sql — also SEEDS zones/monsters/items/loot (INSERT OR IGNORE).
• src/db/migrations/004_inventory.sql — inventory table, FK constraints, partial unique index for equipped slots.
• tests/integration/inventory.test.js — 20 integration tests (13 equip/unequip + 7 consumable).
• public/game.html — dashboard with stats panel, tabbed action panel (Hunt/Inventory), equipment panel, inventory grid.
• public/js/game.js — full hunt UI + inventory UI: load zones, hunt handler, result display, combat log, tab switching, loadInventory, renderEquipmentPanel, renderInventoryGrid, equip/unequip/use handlers, tooltips.
• public/css/main.css — zone cards, combat log, result panel, toast styles, tabs, equipment panel, inventory grid, tooltips, rarity colors.

4. Half-finished / fragile things

• No shop UI yet (Phase 6).
• No expedition UI yet (Phase 7).
• No leaderboard UI yet (Phase 8).
• HP never regenerates naturally; only level-up restores it.
• No restart-persistence test for sessions.
• npm run seed script in package.json points to nonexistent scripts/seed.js.
• Equipment bonuses not yet passed into combat (Issue #5 in STATUS.md).

5. Decisions & deviations from the docs

• D-004..D-007 in docs/DECISIONS.md (combat rounds, equipment counted once, session store, clock).
• Zod query param parsing uses zod.coerce.number() because Express query params are strings.
• Inventory response uses itemId (item.id) and inventoryId (inventory row id) to avoid confusion.
• Consumable effect parsing: regex ^(heal|energy):(\d+)$ on items.effect field.
• Qty decrement avoids CHECK constraint violation: delete directly when qty==1, decrement when qty>1.
• UI uses emoji icons (⚔️🛡️💍🧪📦) for item types per UI_GUIDE recommendation.
• Rarity colors match UI_GUIDE spec (common #b8b0a3, uncommon #5fb36b, rare #4a8fe0, epic #a45ee0, legendary #f2a23a).

6. Gotchas learned

• npm test must be node --test with NO path/glob; files must be named *.test.js. A shell glob once skipped 17 tests.
• better-sqlite3-session-store ignores clear:false; that's why the timer is unref'd.
• Statement caches are per-DB-handle (WeakMap) in huntService; copy that pattern for new services.
• Verify test COUNT, not just "all passing".
• Node.js fetch doesn't persist cookies across calls — extract Set-Cookie header and pass manually in integration tests.
• Express query params are strings, not numbers — use zod.coerce.number() for numeric query params.
• SQL SELECT id from inventory returns the auto-increment row id; rename with AS inventory_id when you also need item_id.
• itemInSlot query must alias id AS inventory_id so existing.inventory_id works in unequip logic.
• Transaction callback args must match the call order exactly — passing qty as the second arg when the callback expects etype silently misapplies the effect.

7. Next-step briefing (6.1)

• Goal: Shop API endpoints — GET /api/shop (list stock), POST /api/shop/buy (buy items), POST /api/shop/sell (sell items). Sell value = 40% of base price. Gold never goes negative.
• Docs: GAME_DESIGN.md §Economy, API.md, BALANCE.md.
• Files to create/modify: src/services/shopService.js, src/routes/shop.js, register in app.js.
• Key rules: Shop stock determined by character level (level-gated). Sell = 40% of buy_price. Use transactions for buy. Item slug → buy_price from items table.

8. Open Known Issues

STATUS.md issues 1–6 (balance, dangling seed script, restart test, equipment-in-combat, HP regen, zone min_level balance).