deadhead-space-freight-tycoon/memory-bank/architecture.md

Architecture

Living reference for how the code is organised. Update it after any save format or command change (implementation plan rule 0.1.9). Decisions and their reasons live in DECISIONS.md.

Packages

Package	Role	Depends on
packages/content	Static game data (locations, ship models, cargo, skills, GameConfig) as Zod-validated TypeScript, plus the content bundle with id lookups.	zod
packages/sim	Pure, deterministic game rules: clock, seeded RNG, positions, distances, travel, fuel, eligibility, contract boards, dispatch validation/records, flight progress, XP, resolution. Completable boards (CR-019, completable.ts): permanentFailure/completability/isCompletable check a contract against ship-and-pilot capability snapshots (FleetMember: model, upgrades, skills, fuel); qualifyingFleet picks the pairs for a location; generateContractBoard with a fleet keeps only completable candidates (up to boardMaxAttempts). No I/O, no Date.now(), no Math.random(). balance/ holds the balance simulation (Step 12.1), outside src/ and the coverage measure. Positions are fixed (CR-015): locationPosition reads the location's position from content. Fuel (fuel.ts, CR-015): legFuel = burn × economic distance(distance ÷ origin factor), fullTankReach (its inverse for a full tank), fuelPriceAt; checkRoute(ship, from, to, config) compares the distance with full-tank reach. Tanks (Step 15.4): ShipState.tank (fuelFu, avgPrice), refuel, affordableRefuel, legFuelCost; validation fails with not-enough-fuel; records carry fuelBurnedFu and fuelCost (burned × average price); resolveDispatch takes an optional fuel block and returns topUp (Auto top-up on landing; new ships are on Manual since CR-018). balance/fuel-share.ts (CR-018): each ship's fuel share of the median payout per route. wouldStrand(model, destination, fuelOnArrivalFu, discovered, content) uses a full tank where the destination sells fuel, else the fuel left (Step 15.5); emergencyFuel gives the offer (amount, price, cost) or null.	content
packages/engine	The game on the device (CR-014): commands over a save document, using storage, the clock and notifications only through injected interfaces. notifications.ts: the schedule is recomputed from the save after every saved change and replaces the platform's (NotificationScheduler: Capacitor on native, no-op on the web). DeviceClock: max(device time + dev offset, last time seen), never backward.	content, schema, sim
packages/schema	Zod schemas for every API request, response and error. Shared by the engine and the client.	sim (error codes), zod
apps/web	React client; runs the engine on the device (CR-014).	content, engine, sim, schema

Conventions

• Times are Unix milliseconds (numbers). A real time is a wall-clock instant; a game time is the instant of the in-game date (realToGame / gameToReal in sim).
• Ids are non-empty strings. Content ids are kebab-case (earth, bulk-hauler).
• Credits are whole numbers.
• Static vs. player data: commands never return static data. The client imports @deadhead/content and joins by id.

API data model (packages/schema)

Shape	Fields
ServerTime	realTime, gameTime
Company	id, name, credits, loanBalance
Ship	id, modelId, name, status (idle / in-flight), locationId (null in flight), dispatchId (null when idle), pilotId, lastArrivalAt (latest resolved arrival, else delivery time; picks the default Contracts location), upgrades ({ upgradeId: level }), stats (effective: speed, capacity, tank capacity and burn rate (CR-015), overhead, handling per tonne), inShopUntil (null unless in the shop now), shop ({ upgradeId, level, until } of the latest job until acknowledged; CR-009)
Pilot	id, name, isAvatar, isVeteran (the deal's veteran, CR-010), xp, level, skills ({ skillId: level }), skillPointsAvailable, assignedShipId, status, locationId (null in flight), dutyHours, dutyLimit, resting, restEndsAt (null unless resting; CR-004)
Bay	id, locationId
LocationState	id, discovered
Contract	mirrors sim Contract: route, cargoTypeId (class), goodId, shipper, priority, deliveryWindowGameHours (Priority only, else null), tier, massTonnes (to 0.1 t under 10 t), payout, requirements, offeredAt/expiresAt, firstContact, optional scriptedId on a scripted tutorial contract (CR-007)
Dispatch	mirrors sim DispatchRecord + status (in-flight / resolved), resolvedAt
ResolutionSummary	dispatchId, shipId, pilotId, originId, destinationId, tutorial, deadhead, fuelCost, goodId / massTonnes / shipper (null for a deadhead, CR-007), credits (net), loanRepayment, pilotPay (hired pilot's profit share, CR-010), pilotXp, discoveredLocationId, scriptedId, restEndsAt (set when the trip ended in mandatory rest), resolvedAt
TutorialState	loanerLocationId (earth / moon), runInFlight, runsCompleted, dealAvailable
GoalState	id, status (incomplete / ready / claimed)
PlayerState	playerId (CR-011), company, ships, pilots, bays, locations, tutorial (null once over), activeDispatches, summaries, goals (empty during the tutorial)

Errors

Every refusal carries { code, message }: the engine's CommandError, which the client turns into an ApiError with the HTTP status the old server sent. code is one of ERROR_CODES: every sim dispatch and reposition validation reason (DISPATCH_FAILURES, REPOSITION_FAILURES), unchanged (CR-007 adds too-slow: the ship can't make a Priority contract's delivery window; CR-012 adds would-strand: from the destination, at arrival plus noStrandMarginGameHours, the ship couldn't reach any other discovered location), plus the server codes in SERVER_ERROR_CODES (validation-error, unauthorized, not-found, insufficient-funds, ...).

API routes (packages/schema/src/routes.ts)

The routes catalog is the list of engine commands (CR-014). Each entry has request (path parameters merged with the body), response and auth (whether it needs a company). method and path are kept from the server's HTTP API: ported tests route by them.

Name	Method & path	Request	Response	Auth
getServerTime	GET /api/time	—	ServerTime	no
createGuest	POST /api/guest	—	{ playerId, state: PlayerState } (playerId is the save id)	no
getPlayerState	GET /api/state	—	PlayerState	yes
buyDispatchOffice / setSpendingFloor	POST /api/company/dispatch-office, /api/company/spending-floor	{} / credits	{ company, dispatchOffice } (CR-020)	yes
setPilotMode / setPilotOrders	POST /api/pilots/:pilotId/mode, /orders	pilotId, mode / orders	{ pilot } (CR-020)	yes
getContractBoard	GET /api/locations/:locationId/board	locationId	{ contracts, periodEndsAt } (only jobs the qualifying fleet can complete, CR-019)	yes
getTutorialBoard	GET /api/tutorial/board	—	{ contracts, periodEndsAt }	yes
createDispatch	POST /api/dispatches	{ kind: "contract", contractId, shipId, pilotId } / { kind: "tutorial", contractId } / { kind: "reposition", shipId, pilotId, destinationId }	{ dispatch }	yes
startUpgrade	POST /api/ships/:shipId/upgrades	shipId, upgradeId (next level; ship idle at an HQ)	{ ship }	yes
buyShip	POST /api/ships	modelId, bayId (one of the player's bays; the ship is delivered there)	{ ship }	yes
leaseBay	POST /api/bays	locationId	{ bay }	yes
hirePilot	POST /api/pilots	locationId (a player bay)	{ pilot }	yes
assignPilot	POST /api/pilots/:pilotId/assign	pilotId, shipId	{ pilot }	yes
unassignPilot	POST /api/pilots/:pilotId/unassign	pilotId	{ pilot }	yes
restPilot	POST /api/pilots/:pilotId/rest	pilotId (idle, not resting)	{ pilot }	yes
spendSkillPoint	POST /api/pilots/:pilotId/skills	pilotId, skillId	{ pilot }	yes
acknowledgeSummaries	POST /api/summaries/acknowledge	dispatchIds, optional shipIds (finished upgrades seen; at least one id overall)	{ acknowledged }	yes
acceptDeal	POST /api/deal/accept	—	PlayerState	yes
exportSave	engine only (CR-014)	—	{ code }: DEADHEAD1. + base64url(gzip(save JSON))	yes
importSave	engine only (CR-014)	code (whitespace ignored)	{ playerId, state }; invalid-save if it isn't a good save	no
devAdvanceClock	POST /api/test/advance-clock	advanceMs	{ offsetMs, realTime }	yes; developer builds only
devAddCredits	POST /api/test/add-credits	amount	{ company }	yes; developer builds only
devPilot	POST /api/test/pilot	pilotId, action: level-up (XP to the next level) / clear-rest (duty 0, rest ended)	PlayerState	yes; developer builds only
devShip	POST /api/test/ship	shipId, action: max-upgrades / reset-upgrades / finish-shop / move (+ locationId, idle ship, discovered place)	PlayerState	yes; developer builds only
devDiscoverAll	POST /api/test/discover-all	—	PlayerState	yes; developer builds only
newCompany	POST /api/company/new	—	PlayerState (the fresh start)	yes
renameCompany	POST /api/company/name	name (trimmed, 3–32 letters, digits, spaces, . , ' & ! ? -)	{ company }	yes
repayLoan	POST /api/loan/repay	amount	{ company }	yes
refuelShip	POST /api/ships/:shipId/refuel	shipId, optional amountFu (absent fills)	{ ship }	yes
setRefuelPolicy	POST /api/ships/:shipId/refuel-policy	shipId, policy (auto / manual)	{ ship }	yes
orderEmergencyFuel	POST /api/ships/:shipId/emergency-fuel	shipId	{ ship }; cost added to the loan	yes
claimGoal	POST /api/goals/:goalId/claim	goalId	{ company }	yes

Save document (packages/schema/src/save.ts, CR-014)

One document per company on the device, validated on every load and save: saveVersion (currently 5; 1 → 2 added fuel tanks, CR-015; 2 → 3 put every ship on Manual refueling, CR-018; 3 → 4 dropped stored boards, CR-019; 4 → 5 added pilot mode and orders and the company's dispatchOffice and npcSpendingFloor, CR-020; 5 → 6 added pilot nextDecisionAt and emptyPeriods and dispatch independent, CR-020), saveId, lastTimeSeen (the clock never goes below it), player (world seed, tutorial state, deal accepted), company (name, credits, loan), ships (with upgrades as a level map, shop fields, and fuelFu, fuelAvgPrice, refuelPolicy since CR-015), pilots, bays, discoveredLocations, contractBoards (stored boards), dispatches (sim record, status, resolution, acknowledged), acceptedContracts, claimedGoals. It mirrors the old server's database tables without player ids; the stored contract, dispatch record and resolution are type-checked against the sim types. migrateSave(raw) steps an older save through SAVE_MIGRATIONS (applyMigrations) and validates it, returning a readable error instead of throwing.

Commands (packages/engine/src/game/): GameEngine.call(name, input) runs the route catalog's endpoints on the save, with the same schemas and error codes (CommandError); getPlayerState with no save answers unauthorized. Every command resolves due arrivals first and prunes on save; saves are skipped when nothing changed. stats keeps lifetime delivery counts for goals, so seen trips older than savedDispatchRetentionRealHours can be pruned.

Resolution loop (packages/engine/src/loop.ts): on load, on resume and every 5 s, resolveDue applies due arrivals (saving only if any) and reports rests and shop jobs that ended, so the app refreshes; timer and resume events come from a LoopHost.

Storage (packages/engine/src/storage.ts): SaveStorage keeps the save in slot main and the previous three in backup-1..3 (rotated on every save), falling back to the newest valid backup if the main save is unreadable. Backends store text per slot, all-or-nothing: MemoryBackend (tests), IndexedDbBackend (web, database deadhead, store saves), FilesystemBackend (native, deadhead/<slot>.json in the Capacitor data directory, temp file then rename).

The server (removed)

Until Step 14.11 a Fastify API with Postgres (Drizzle), Better Auth guest sessions and pg-boss jobs ran the game; the engine is a port of its game logic and its tests. Its code and this document's sections on it are in the git history before the commit "Step 14.11".

Deployment (deploy/)

File	Role
compose.yml	One service (project deadhead): web, Caddy serving plain HTTP on container port 80, published on HTTP_PORT (default 8080) for Nginx Proxy Manager to forward to
web.Dockerfile, Caddyfile	Caddy image with the built app on :80: client routes fall back to index.html, hashed assets cached for a year, shell, service worker and manifest never; HTTPS is NPM's
README.md	Setup behind Nginx Proxy Manager, start/update, other static hosts
.env.example	HTTP_PORT; copy to deploy/.env
check.sh	Builds and starts the site under a throwaway project, checks shell, routes, caching and compression, removes it

Client (apps/web)

Vite + React 19 + Tailwind 4, React Router 8 (declarative routes). The game runs in the page; there is no API to call.

Module	Role
src/api/client.ts	The ApiClient interface (typed by the route catalog) and ApiError; src/api/engine-client.ts implements it over the engine. Its optional notificationPrompt() settles once the permission prompt asked for after the deal is answered (CR-017)
src/api/context.tsx	ApiProvider / useApi (tests inject a fake)
src/clock/clock.ts	Zustand useClock: offset to the engine clock (which includes the developer offset), serverNow(), 1 s ticker
src/state/player.ts	usePlayerState (TanStack Query, key player-state): null means no company on this device; refetch on focus and on arrival
src/App.tsx	Clock sync; loading / start screen / routed layout
src/layout/Layout.tsx	Header (credits, game clock), screen outlet, bottom tab bar
src/routes.ts	Screen list shared by router and navigation
src/map/art/manifest.json	Map art manifest (CR-003): asset id → { kind, file } in public/assets/map/ (never edited); null file = missing, placeholder used
scripts/map-art.mjs	Generates public/assets/map-gen/ (<id>@1x.png, <id>@2x.png, bg.webp) from the manifest with sharp; output committed
src/map/style.ts	Map presentation config (CR-003): sprite sizes, zoom scale limits, child-body offsets, badges, tap size, parallax, colors; validated by mapStyleSchema
src/map/art/load.ts, art/visuals.ts	Load the generated art as one PixiJS bundle (2x at DPR ≥ 2); texture-or-placeholder per scene item (decision 0.5.41)
src/map/layout.ts	Pure screen layout: backgroundRect, spriteScale, childOffset, layoutScene (centres, sizes, tap targets; used by renderer and hit test), decorate (label and badge placement)
src/map/belt.ts	The asteroid belt (CR-016, visual only): radii on the compressed scale, ringGeometry (the haze mesh, built once in map units), hazeStripPixels/hazeSource (generated haze unless belt-haze.png exists), beltRocks (220 seeded rocks) and placeRocks (screen placement, clear of Ceres)
src/map/overlays.ts	Per-location state overlays (lock, desaturate/dim, HQ marker, idle badge), applied by the renderer
src/map/ticker.ts	runWhileVisible: pause the map's ticker while the page is hidden; stop it on unmount
src/map/renderer.ts	MapRenderer: all PixiJS drawing for the map, layer by layer; MapCanvas owns the app, input and loading state
vite.config.ts (PWA)	vite-plugin-pwa (Step 11.1): manifest, generateSW precache of the shell, woff2 fonts, map-gen art and icons (public/icons, from scripts/icons.mjs)
e2e/*.e2e.ts	Playwright tests against vite preview of two builds made by build:e2e: the test build in dist (developer tools, window.deadhead hook; engine commands run through the hook) and the production build in dist-production (Step 14.11: loads only its own files)
src/state/preferences.ts	Device preferences (CR-011): clock and countdown format, reduced-motion override, dismissed tips, saved map camera, notifications on/off (CR-014); local storage, every access wrapped
src/screens/*	HQ, Contracts (TutorialBoard / LocationBoards + DispatchSheet), Fleet, Pilots, Market, Locations, StartScreen
src/components/*	AwaySummary dialog, Countdown
src/components/Fuel.tsx	Fuel UI (CR-015): FuelGauge, the ShipFuel sheet (refuel, policy, emergency fuel), FuelPrice (cheapest marked), refuelForLeg ("Refuel here first")
src/state/actions.ts	useLoadedPlayer, useGameAction(route) (mutation + invalidate state and boards)
src/map/*	System map: projection (square-root radial scale), camera (Zustand pan/zoom), scene (locations, flights, idle badges), hitTest, MapCanvas (PixiJS v8, lazy-loaded with the Map screen)
src/game.ts, src/format.ts	Sim-based predictions (distance, trip time) and display formatting

Since CR-014 the client runs the game itself: src/platform/game.ts (storage, device clock, tab lock, engine), src/api/engine-client.ts (the ApiClient over engine commands), src/GameRoot.tsx (tab lock screen, resolution loop, the window.deadhead test hook in developer builds). src/platform/notifications.ts picks the notification scheduler; src/platform/context.tsx gives screens the Game (debug info). src/screens/SaveSettings.tsx: Export save and Import save. src/components/SkillPointPrompt.tsx (CR-017): the one-time skill point pop-up (tip id skill-points), shown once the tutorial is over, the permission prompt is answered and some pilot has unspent points.

On the device the client keeps the save (IndexedDB, or files on native) and, in local storage, device preferences, seen board ids and, in developer builds, the developer clock offset. The game works the same with or without a network.

Independent pilots and catch-up (CR-020)

packages/engine/src/game/catchup.ts: catchUp(save, until, { decideUntil, maxEvents, viewedContractId }) replays time as an event queue. It takes the next in-flight arrival or the next Independent pilot's nextDecisionAt, in time order: arrivals first at the same moment, then pilots by id. Each arrival resolves at its own time. A decision point checks rest, the shop and the first-look window (each pushes nextDecisionAt later), then asks the sim's chooseAction about the pilot's board. It acts through the normal refuelShip, dispatchContract and dispatchReposition, with ids made from the pilot and the moment (ind-…), so the same time always gives the same save. Waiting schedules the next board period's first-look end and counts empty periods away from home. A trip's landing schedules the next decision a turnaround after the arrival, or after the rest it triggers. Decisions stop maxCatchUpRealDays after the save's lastTimeSeen (decideUntil), and later ones resume from until. Every command runs catchUp to its now before it acts. GameEngine.resolveDue(since, { chunkEvents, onProgress }) runs the loop's pass in chunks (500 events, one save each), with onProgress(0…1) in between. GameEngine.setViewedContract(id) tells pilots which contract the player has open. Dispatches an Independent pilot chose are flagged independent, and no notification is scheduled for them.