import {Signal, signal} from "@preact/signals-core";

export type Entity = {
  id: string;
};

export type EntityAccessor<T extends Entity> = {
  id: string;
  value: T;
}

export function createEntityCollection<T extends Entity>() {
  const collection = signal({} as Record<string, Signal<T>>);
  const remove = (...ids: string[]) => {
    collection.value = Object.fromEntries(
      Object.entries(collection.value).filter(([id]) => !ids.includes(id)),
    );
  };
  
  const add = (...entities: T[]) => {
    collection.value = {
      ...collection.value,
      ...Object.fromEntries(entities.map((entity) => [entity.id, signal(entity)])),
    };
  };
  
  const get = (id: string) => {
    return {
      id,
      get value(){
        return collection.value[id]?.value;
      },
      set value(value: T){
        const signal = collection.value[id];
        if(signal)signal.value = value;
      }
    }
  }
  
  return {
    collection,
    remove,
    add,
    get
  }
}