import { Metrics } from './Metrics';
import { MetricsType } from './MetricsType';
import { MetricsValue } from './MetricsValue';

export class MetricsCalculator {
  constructor(private readonly metrics: Metrics[]) {}

  sum(findType: MetricsType) {
    const value = this.findAllByType(findType).reduce((sum, value) => sum + value.valueOf(), 0);

    return new MetricsValue(findType, value);
  }

  getLength() {
    return this.metrics.length;
  }

  average(findType: MetricsType) {
    const length = this.getLength();
    const sum = this.sum(findType);

    return new MetricsValue(findType, sum.valueOf() ? sum.valueOf() / length : 0);
  }

  max(findType: MetricsType) {
    const values = new Set(this.findAllByType(findType));

    return new MetricsValue(findType, Math.max(...values, 0));
  }

  min(findType: MetricsType) {
    const values = new Set(this.findAllByType(findType));

    return new MetricsValue(findType, Math.min(...values, Infinity));
  }

  private findAllByType(findType: MetricsType) {
    return this.metrics
      .map((row) => row.getByType(findType)!)
      .filter((row) => row && !row.isEmpty())
      .map((row) => Number(row));
  }
}