import { Dict } from '../dict';

export class AttrMap<C, K, V> {
  constructor(
    entries?: Iterable<readonly [C, K, V]>,
    private readonly KeyMap: new <K, V>(entries?: Iterable<readonly [K, V]> | null) => Dict<K, V> = WeakMap,
    private readonly ValueMap: new <K, V>(entries?: Iterable<readonly [K, V]> | null) => Dict<K, V> = Map
  ) {
    if (entries) for (const { 0: c, 1: k, 2: v } of entries) {
      this.set(c, k, v);
    }
  }
  private readonly memory = new this.KeyMap<C, Dict<K, V>>();
  public get(ctx: C, key: K): V | undefined {
    return this.memory.get(ctx)?.get(key);
  }
  public set(ctx: C, key: K, value: V): this {
    this.memory.get(ctx)?.set(key, value) || this.memory.set(ctx, new this.ValueMap([[key, value]]));
    return this;
  }
  public has(ctx: C): boolean
  public has(ctx: C, key: K): boolean
  public has(ctx: C, key?: K): boolean {
    return arguments.length < 2
      ? this.memory.has(ctx)
      : this.memory.get(ctx)?.has(key!) ?? false;
  }
  public delete(ctx: C): boolean
  public delete(ctx: C, key: K): boolean
  public delete(ctx: C, key?: K): boolean {
    return arguments.length < 2
      ? this.memory.delete(ctx)
      : this.memory.get(ctx)?.delete(key!) ?? false;
  }
}