feat: add Session and stage active check

packages/game/src/Session.ts

@@ -0,0 +1,17 @@
+import { ISession } from './types'
+
+export class Session implements ISession {
+  private completed: string[] = []
+
+  constructor({ completedStages }: ISession) {
+    this.completed = completedStages
+  }
+
+  get completedStages() {
+    return this.completed
+  }
+
+  complete(stageId: string) {
+    this.completed.push(stageId)
+  }
+}

packages/game/src/Stage.ts

@@ -1,15 +1,17 @@
-import { IStage, ICommand, IFileExistenceChecker } from './types'
+import { IStage, ICommand, IFileExistenceChecker, ISession } from './types'
 import { Condition } from './condition/Condition'
 
 export class Stage {
   id: string
   name: string
-  condition: Condition
+  private condition: Condition
+  private requirements: string[]
 
-  constructor({ id, name, condition }: IStage) {
+  constructor({ id, name, condition, requirements }: IStage) {
     this.id = id
-    this.name = name
+    this.name = name || ''
     this.condition = new Condition(condition)
+    this.requirements = requirements || []
   }
 
   async satisfies(
@@ -18,4 +20,18 @@ export class Stage {
   ): Promise<boolean> {
     return this.condition.match(command) && this.condition.check(checker)
   }
+
+  private checkRequirements(session: ISession): boolean {
+    return this.requirements.every((req) =>
+      session.completedStages.includes(req)
+    )
+  }
+
+  private finished(session: ISession): boolean {
+    return session.completedStages.includes(this.id)
+  }
+
+  active(session: ISession): boolean {
+    return !this.finished(session) && this.checkRequirements(session)
+  }
 }

packages/game/src/types.ts

@@ -35,6 +35,11 @@ export interface IFileExistenceChecker {
 
 export interface IStage {
   id: string
-  name: string
+  name?: string
+  requirements?: string[]
   condition: ICondition
 }
+
+export interface ISession {
+  completedStages: string[]
+}

packages/game/test/stage.test.ts

@@ -2,6 +2,7 @@ import { test, expect } from '@jest/globals'
 import { Stage } from '../src/Stage'
 import { FileType } from '../src/types'
 import { MockFileChecker } from './asyncCondition.test'
+import { Session } from '../src/Session'
 
 const checker = new MockFileChecker()
 
@@ -67,3 +68,21 @@ test('check stage with async condition falsy', async () => {
   })
   expect(await stage.satisfies({}, checker)).toBe(false)
 })
+
+test('stage active checks', () => {
+  const session = new Session({
+    completedStages: ['stage1'],
+  })
+  const stage3 = new Stage({
+    id: 'stage3',
+    requirements: ['stage1', 'stage2'],
+    condition: {},
+  })
+  expect(stage3.active(session)).toBe(false)
+
+  session.complete('stage2')
+  expect(stage3.active(session)).toBe(true)
+
+  session.complete('stage3')
+  expect(stage3.active(session)).toBe(false)
+})