import { DateTime, Duration } from "luxon";

export default class Event {
  public summary: string;
  public description: string;
  public start: DateTime;
  public duration: Duration;

  public constructor(json_data: Record<string, string>) {
    this.summary = json_data["summary"];
    this.description = json_data["description"];
    this.start = DateTime
      .fromISO(json_data["dtstart"])
      .setLocale(navigator.language);
    const end = DateTime
      .fromISO(json_data["dtend"])
      .setLocale(navigator.language);

    this.duration = end.diff(this.start);
  }

  public get hash(): string {
    const str = JSON.stringify(this);

    // source: https://gist.github.com/hyamamoto/fd435505d29ebfa3d9716fd2be8d42f0?permalink_comment_id=2775538#gistcomment-2775538
    let hash = 0;
    for (let i = 0; i < str.length; i++)
      hash = Math.imul(31, hash) + str.charCodeAt(i) | 0;

    return new Uint32Array([hash])[0].toString(36);
  }
}