import * as plugins from './smartclickhouse.plugins.js';

export class ClickhouseResultSet<T> {
  public rows: T[];
  public rowCount: number;

  constructor(rows: T[]) {
    this.rows = rows;
    this.rowCount = rows.length;
  }

  public first(): T | null {
    return this.rows.length > 0 ? this.rows[0] : null;
  }

  public last(): T | null {
    return this.rows.length > 0 ? this.rows[this.rows.length - 1] : null;
  }

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

  public toArray(): T[] {
    return this.rows;
  }

  public map<U>(fn: (row: T) => U): U[] {
    return this.rows.map(fn);
  }

  public filter(fn: (row: T) => boolean): ClickhouseResultSet<T> {
    return new ClickhouseResultSet<T>(this.rows.filter(fn));
  }

  public toObservable(): plugins.smartrx.rxjs.Observable<T> {
    return new plugins.smartrx.rxjs.Observable<T>((observer) => {
      for (const row of this.rows) {
        observer.next(row);
      }
      observer.complete();
    });
  }
}