Fix circular array initialization

[e-mobility-charging-stations-simulator.git] / src / utils / CircularArray.ts

const DEFAULT_CIRCULAR_ARRAY_SIZE = 2000;

export default class CircularArray<T> extends Array<T> {
  public size: number;

  constructor(size: number = DEFAULT_CIRCULAR_ARRAY_SIZE, ...items: T[]) {
    super();
    this.checkSize(size);
    this.size = size;
    if (arguments.length > 1) {
      this.push(...items);
    }
  }

  public push(...items: T[]): number {
    const length = super.push(...items);
    if (length > this.size) {
      super.splice(0, length - this.size);
    }
    return this.length;
  }

  public unshift(...items: T[]): number {
    const length = super.unshift(...items);
    if (length > this.size) {
      super.splice(this.size, items.length);
    }
    return length;
  }

  public concat(...items: (T | ConcatArray<T>)[]): CircularArray<T> {
    const concatenatedCircularArray = super.concat(
      items as T[]
    ) as CircularArray<T>;
    concatenatedCircularArray.size = this.size;
    if (concatenatedCircularArray.length > concatenatedCircularArray.size) {
      concatenatedCircularArray.splice(
        0,
        concatenatedCircularArray.length - this.size
      );
    }
    return concatenatedCircularArray;
  }

  public splice(start: number, deleteCount?: number, ...items: T[]): T[] {
    let itemsRemoved: T[];
    if (arguments.length >= 3 && typeof deleteCount !== 'undefined') {
      itemsRemoved = super.splice(start, deleteCount);
      // FIXME: that makes the items insert not in place
      this.push(...items);
    } else if (arguments.length === 2) {
      itemsRemoved = super.splice(start, deleteCount);
    } else {
      itemsRemoved = super.splice(start);
    }
    return itemsRemoved;
  }

  public resize(size: number): void {
    this.checkSize(size);
    if (size === 0) {
      this.length = 0;
    } else if (size < this.size) {
      for (let i = size; i < this.size; i++) {
        super.pop();
      }
    }
    this.size = size;
  }

  public empty(): boolean {
    return this.length === 0;
  }

  public full(): boolean {
    return this.length === this.size;
  }

  private checkSize(size: number) {
    if (size < 0) {
      throw new RangeError('Invalid circular array size');
    }
  }
}