classDiagram
    class IdManager {
        -currentIdCount: number
        -freeIds: number[]
        -getNextId(): number
        +allocateId(): number
        +freeId(id: number): void
    }
    
    class ComponentManager {
        -instance: ComponentManager
        -registeredComponents: Map<string, Class>
        +getInstance(): ComponentManager
        +register(name: string, class: Class): boolean
        +create(name: string): AbstractComponent
    }
    
    class EntityManager {
        -idManager: IdManager
        -componentManager: ComponentManager
        -entities: Iterable<Array<Component>>
        +setEntity(): Iterable<Array<Component>>
        +removeEntity(id): boolean
        +getEntities(): Iterable<Array<Component>>
        +addComponent(entityId: number, component: Component): boolean
        +getComponents(entityId: number): Array<Component>
        +removeComponent(entityId: number): boolean
    }
    
    class ECS {
        -instance: ECS
        +entityManager: EntityManager
        +componentManager: ComponentManager
        -systems: Set<ISystem>
        +getInstance(): ECS
        +addSystem(system: AbstractSystem): boolean
        +update(): void
    }
    
    class ISystem {
        <<Interface>>
        +update(deltaTime: number): void
    }
    
    IdManager <-- EntityManager
    ComponentManager <-- EntityManager
    ComponentManager <-- ECS
    EntityManager <-- ECS
    ISystem <-- ECS
    
    EntityManager "1" -- ECS