/* eslint-disable @typescript-eslint/explicit-member-accessibility */
/**
 * Created by sv2 on 2/18/17.
 * Set of Longest Requests
 * Requests with longest observed handle time, since star
 */

import { RequestResponseRecord } from "./interfaces/request-response-record.interface";

export class SwsLongestRequests {
  // Highest duration from all stored requests
  private highest = -1;

  // Lowest duration from all stored requests
  private lowest = -1; // will be updated by first request

  // Max number of requests to keep.
  // Should not be too big as we're going keep ordered array of longest requests
  private capacity = 100;

  // true if full
  private full = false;

  // Store 100 longest requests
  private longest_requests: RequestResponseRecord[] = [];

  public getStats(): RequestResponseRecord[] {
    return this.longest_requests;
  }

  private placeReqResData(rrr: RequestResponseRecord): void {
    const duration = rrr.responsetime;

    if (duration >= this.highest) {
      this.highest = duration;
      if (this.lowest === -1) this.lowest = duration; // this would be a case of first request
      this.longest_requests.push(rrr); // add to the end as highest
      return;
    }

    if (duration <= this.lowest) {
      this.lowest = duration;
      this.longest_requests.unshift(rrr); // add to the front as lowest
      return;
    }

    // we need to find right place for it
    // iterate over array and insert new record right before longer one
    let idx = -1;
    for (let i = 0; i < this.longest_requests.length && idx === -1; i += 1) {
      if (duration < this.longest_requests[i].responsetime) {
        idx = i;
      }
    }

    if (idx !== -1) {
      this.longest_requests.splice(idx, 0, rrr);
    }
  }

  // Check if this qualifies as longest request, and store is yes
  public processReqResData(rrr: RequestResponseRecord): void {
    const duration = rrr.responsetime;

    if (!this.full) {
      // Filling up - store all requests
      this.placeReqResData(rrr);
      this.full = this.longest_requests.length === this.capacity;
      return;
    }

    // Request is ignored when it's handle time < lowest, and no more space
    if (duration < this.lowest) return;

    // Evict smallest one
    this.longest_requests.shift();

    // First entry duration is now the smallest one
    this.lowest = this.longest_requests[0].responsetime;

    this.placeReqResData(rrr);
  }
}