game: save lifecycle — auto-init, world state, jump with adjacency validation + chart growth

2026-09-28 21:28:14 +00:00
parent 1634c0602e
commit 58ac64af4f
2 changed files with 279 additions and 0 deletions
@@ -0,0 +1,132 @@
+import { mkdtemp, rm } from 'node:fs/promises'
+import { tmpdir } from 'node:os'
+import path from 'node:path'
+import { afterAll, describe, expect, it } from 'vitest'
+import { openGameDb, type GameDb } from '@/lib/db/client'
+import { getWorldState, jumpToSystem, type WorldState } from './save'
+
+const dirs: string[] = []
+
+async function freshFile(): Promise<{ db: GameDb; file: string }> {
+  const dir = await mkdtemp(path.join(tmpdir(), 'sw-save-test-'))
+  dirs.push(dir)
+  const file = path.join(dir, 'test.db')
+  return { db: await openGameDb(file), file }
+}
+
+afterAll(async () => {
+  for (const d of dirs) await rm(d, { recursive: true, force: true })
+})
+
+function currentOf(world: WorldState): WorldState['systems'][number] {
+  const current = world.systems.filter((s) => s.current)
+  expect(current).toHaveLength(1)
+  return current[0]
+}
+
+describe('ensureSave / getWorldState', () => {
+  it('auto-initializes a save on first read: start + 6 neighbours, turn 0, new_game event', async () => {
+    const { db } = await freshFile()
+    const world = await getWorldState(db)
+
+    expect(world.turn).toBe(0)
+    expect(world.systems).toHaveLength(7)
+    expect(currentOf(world).discovered).toBe(true)
+    expect(world.systems.filter((s) => !s.discovered)).toHaveLength(6)
+    expect(world.edges).toHaveLength(12) // start↔each neighbour + ring cycle
+
+    const ids = new Set(world.systems.map((s) => s.id))
+    for (const [a, b] of world.edges) {
+      expect(ids.has(a)).toBe(true)
+      expect(ids.has(b)).toBe(true)
+    }
+
+    const rows = db.raw.exec('SELECT type, turn FROM events ORDER BY id')
+    expect(rows[0].values).toEqual([['new_game', 0]])
+  })
+
+  it('is idempotent — a second read does not regenerate the world', async () => {
+    const { db } = await freshFile()
+    const first = await getWorldState(db)
+    const second = await getWorldState(db)
+    expect(second).toEqual(first)
+  })
+})
+
+describe('jumpToSystem validation', () => {
+  it('rejects unknown systems with 404 and jumping to the current system with 409', async () => {
+    const { db } = await freshFile()
+    const world = await getWorldState(db)
+    const start = currentOf(world)
+
+    await expect(jumpToSystem(db, 999_999)).rejects.toMatchObject({ status: 404 })
+    await expect(jumpToSystem(db, start.id)).rejects.toMatchObject({ status: 409 })
+
+    const after = await getWorldState(db)
+    expect(after.turn).toBe(0) // rejected jumps mutate nothing
+    expect(currentOf(after).id).toBe(start.id)
+  })
+
+  it('rejects non-adjacent systems with 409 and leaves state untouched', async () => {
+    const { db } = await freshFile()
+    const w0 = await getWorldState(db)
+    const start = currentOf(w0)
+
+    // Every initial neighbour is adjacent to the start, so jump once first.
+    const n0 = w0.systems.find((s) => !s.current)!
+    await jumpToSystem(db, n0.id)
+    const w1 = await getWorldState(db)
+    expect(currentOf(w1).id).toBe(n0.id)
+
+    // A system with no route to the current one (ring members two steps away qualify).
+    const adjacent = new Set(
+      w1.edges.filter(([a, b]) => a === n0.id || b === n0.id).flatMap(([a, b]) => [a, b]),
+    )
+    const far = w1.systems.find((s) => !adjacent.has(s.id))!
+
+    await expect(jumpToSystem(db, far.id)).rejects.toMatchObject({ status: 409 })
+    const after = await getWorldState(db)
+    expect(after.turn).toBe(1)
+    expect(currentOf(after).id).toBe(n0.id)
+  })
+})
+
+describe('jumpToSystem success path', () => {
+  it('sets current, increments turn, discovers the target and grows the chart', async () => {
+    const { db } = await freshFile()
+    const w0 = await getWorldState(db)
+    const start = currentOf(w0)
+    const target = w0.systems.find((s) => !s.current)! // all initial neighbours are adjacent to the start
+
+    const after = await jumpToSystem(db, target.id)
+
+    expect(after.turn).toBe(1)
+    expect(currentOf(after).id).toBe(target.id)
+    expect(after.systems.find((s) => s.id === target.id)!.discovered).toBe(true)
+
+    // Expansion: 4 new undiscovered neighbours around the target, each routed to it.
+    const fresh = after.systems.filter((s) => !w0.systems.some((p) => p.id === s.id))
+    expect(fresh).toHaveLength(4)
+    expect(fresh.every((s) => !s.discovered)).toBe(true)
+    for (const n of fresh) {
+      expect(after.edges.some(([a, b]) => (a === target.id && b === n.id) || (a === n.id && b === target.id))).toBe(true)
+    }
+
+    const rows = db.raw.exec('SELECT type, turn FROM events ORDER BY id')
+    expect(rows[0].values).toEqual([['new_game', 0], ['jump', 1]])
+  })
+
+  it('persists the current system and turn across a DB reopen (container restart)', async () => {
+    const { db, file } = await freshFile()
+    const w0 = await getWorldState(db)
+    const target = w0.systems.find((s) => !s.current)!
+    const after = await jumpToSystem(db, target.id)
+
+    const reopened = await openGameDb(file) // a new process would see the same file
+    const again = await getWorldState(reopened)
+
+    expect(again.turn).toBe(after.turn)
+    expect(currentOf(again).id).toBe(target.id)
+    expect(again.systems).toHaveLength(after.systems.length)
+  })
+})
@@ -0,0 +1,147 @@
+import { eq } from 'drizzle-orm'
+import type { GameDb } from '@/lib/db/client'
+import { persist } from '@/lib/db/client'
+import * as schema from '@/lib/db/schema'
+import { generateRing, generateStartRegion, mulberry32 } from './world'
+
+// Save lifecycle: auto-init on first hit, world state reads, and the jump action.
+// Single-player by design — exactly one save row ever exists, so every query below is
+// unscoped (there is nothing to scope against).
+
+export interface WorldSystemDto {
+  id: number
+  name: string
+  x: number
+  y: number
+  discovered: boolean
+  current: boolean
+}
+
+export interface WorldState {
+  systems: WorldSystemDto[]
+  edges: [number, number][] // undirected system-id pairs, deduped + sorted for stable output
+  turn: number
+}
+
+// Carries an HTTP status so route handlers can map failures to responses without re-parsing.
+export class JumpError extends Error {
+  constructor(
+    public readonly status: number,
+    message: string,
+  ) {
+    super(message)
+  }
+}
+
+function newSeed(): string {
+  const buf = new Uint32Array(1)
+  crypto.getRandomValues(buf)
+  return String(buf[0])
+}
+
+// Deterministic per save+turn: the whole world of a seed is reproducible from (seed, turn).
+function expansionRng(seed: string, turn: number): () => number {
+  return mulberry32((Number(seed) + turn * 1_000_003) >>> 0)
+}
+
+async function insertSystems(db: GameDb, saveId: number, systems: { name: string; x: number; y: number }[], discovered: boolean): Promise<Map<string, number>> {
+  const rows = await db.db
+    .insert(schema.solarSystems)
+    .values(systems.map((s) => ({ saveId, name: s.name, x: s.x, y: s.y, discovered })))
+    .returning({ id: schema.solarSystems.id, name: schema.solarSystems.name })
+  return new Map(rows.map((r) => [r.name, r.id]))
+}
+
+async function insertRoutes(db: GameDb, edges: [number, number][], resolve: (index: number) => number): Promise<void> {
+  for (const [a, b] of edges) {
+    const from = resolve(a)
+    const to = resolve(b)
+    await db.db.insert(schema.jumpRoutes).values({ fromSystem: from, toSystem: to })
+    await db.db.insert(schema.jumpRoutes).values({ fromSystem: to, toSystem: from }) // both directions → adjacency is a single-row lookup
+  }
+}
+
+// Creates the save + starting region when the DB has none. No-op otherwise — safe to call
+// on every request (single player, one process: check-then-insert cannot race in practice).
+export async function ensureSave(db: GameDb): Promise<void> {
+  const existing = await db.db.select().from(schema.saves).limit(1)
+  if (existing.length > 0) return
+
+  const seed = newSeed()
+  const region = generateStartRegion(mulberry32(Number(seed)))
+  const nowIso = new Date().toISOString()
+
+  const [save] = await db.db.insert(schema.saves).values({ seed, turn: 0, createdAt: nowIso }).returning()
+  // All inserted as undiscovered first; the start is then marked discovered + current.
+  const ids = await insertSystems(db, save.id, [region.start, ...region.neighbors], false)
+  const startId = ids.get(region.start.name)!
+  await db.db.update(schema.solarSystems).set({ discovered: true, isCurrent: true }).where(eq(schema.solarSystems.id, startId))
+
+  const resolve = (index: number) => (index === 0 ? startId : ids.get(region.neighbors[index - 1].name)!)
+  await insertRoutes(db, region.edges, resolve)
+
+  await db.db.insert(schema.events).values({ saveId: save.id, turn: 0, type: 'new_game', message: `New game — seed ${seed}, starting system ${region.start.name}`, createdAt: nowIso })
+  await persist(db)
+}
+
+export async function getWorldState(db: GameDb): Promise<WorldState> {
+  await ensureSave(db)
+  const [save] = await db.db.select().from(schema.saves).limit(1)
+  const systems = await db.db.select().from(schema.solarSystems)
+  const routes = await db.db.select().from(schema.jumpRoutes)
+
+  // Dedupe the stored directed pairs into sorted undirected edges.
+  const seen = new Set<string>()
+  const edges: [number, number][] = []
+  for (const r of routes) {
+    const a = Math.min(r.fromSystem, r.toSystem)
+    const b = Math.max(r.fromSystem, r.toSystem)
+    const key = `${a}-${b}`
+    if (!seen.has(key)) {
+      seen.add(key)
+      edges.push([a, b])
+    }
+  }
+
+  return {
+    systems: systems.map((s) => ({ id: s.id, name: s.name, x: s.x, y: s.y, discovered: s.discovered, current: s.isCurrent })),
+    edges,
+    turn: save.turn,
+  }
+}
+
+export async function jumpToSystem(db: GameDb, systemId: number): Promise<WorldState> {
+  await ensureSave(db)
+  const [save] = await db.db.select().from(schema.saves).limit(1)
+  const systems = await db.db.select().from(schema.solarSystems)
+
+  const target = systems.find((s) => s.id === systemId)
+  if (!target) throw new JumpError(404, `Unknown system ${systemId}`)
+  const current = systems.find((s) => s.isCurrent)!
+  if (current.id === target.id) throw new JumpError(409, 'Already at this system')
+
+  const routes = await db.db.select().from(schema.jumpRoutes)
+  const adjacent = routes.some((r) => r.fromSystem === current.id && r.toSystem === target.id)
+  if (!adjacent) throw new JumpError(409, `${target.name} is not reachable from ${current.name}`)
+
+  const turn = save.turn + 1
+  await db.db.update(schema.solarSystems).set({ isCurrent: false }).where(eq(schema.solarSystems.id, current.id))
+  await db.db.update(schema.solarSystems).set({ isCurrent: true, discovered: true }).where(eq(schema.solarSystems.id, target.id))
+
+  if (!target.discovered) {
+    // Growing the chart: a ring of new (undiscovered) neighbours around the newly reached
+    // system, so there is always somewhere to jump next and a route back.
+    const rng = expansionRng(save.seed, turn)
+    const takenNames = new Set(systems.map((s) => s.name))
+    const ring = generateRing(rng, target.x, target.y, takenNames, systems)
+    const ids = await insertSystems(db, save.id, ring.systems, false)
+    const resolve = (index: number) => (index === 0 ? target.id : ids.get(ring.systems[index - 1].name)!)
+    await insertRoutes(db, ring.edges, resolve)
+  }
+
+  await db.db.update(schema.saves).set({ turn }).where(eq(schema.saves.id, save.id))
+  await db.db.insert(schema.events).values({ saveId: save.id, turn, type: 'jump', message: `Jumped to ${target.name}`, createdAt: new Date().toISOString() })
+  await persist(db)
+
+  return getWorldState(db)
+}