import { EventEmitter, Injectable } from '@angular/core';

@Injectable()
export class MQTTEntity implements iMQTTEntityBase {
  protected _name: string = '';
  protected _stat_t: string = 'state/topic';
  protected _uniq_id: string = '';
  private _size: number = 0;

  attrs = new Set(['name', 'stat_t', 'uniq_id']);
  topic_updates = new EventEmitter<string>();
  readonly ent_type: string = 'base';

  get name() {
    return this._name;
  }

  set name(name: string) {
    this._name = name;
    if (name == '') return;
    this._uniq_id = name + '_' + hash(name);
    this.topic_updates.next('stat_t');
  }

  get stat_t() {
    return this._stat_t;
  }

  set stat_t(stat: string) {
    this._stat_t = stat;
  }

  get uniq_id() {
    return this._uniq_id;
  }

  set uniq_id(uniq_id: string) {
    this._uniq_id = uniq_id;
    this.topic_updates.next('stat_t');
  }

  get display_name() {
    if (this._uniq_id != '') {
      return this._uniq_id;
    }
    return this._name;
  }

  publish_topics(index: number = 1): string[] {
    return [`String stat_topic_${index} = "${this.stat_t}";`];
  }

  toJSON(): { [key: string]: string | {} } {
    let jsonObject: { [key: string]: string | {} } = {};
    for (let prop_name of this.attrs.values()) {
      let property = this[prop_name as keyof this];
      if (property == '') continue;
      jsonObject[prop_name] = String(property);
    }
    return jsonObject;
  }

  get size(): number {
    this._size = JSON.stringify(this.toJSON()).length;
    return this._size;
  }

  getProperty(name: string): any {
    if (!this.attrs.has(name)) return '';
    return this[name as keyof this];
  }

  setProperty(name: string, value: any) {
    if (!this.attrs.has(name)) return;
    this[name as keyof this] = value;
  }
}

export class DeviceClass {
  value: number = 0;
  choices: string[] = ['None'];

  constructor(choices: string[]) {
    this.choices = choices;
  }

  toString(): string {
    return this.choices[this.value];
  }
}

export interface iMQTTEntityBase {
  name: string;
  stat_t: string;
  uniq_id: string;
  display_name: string;

  attrs: Set<string>;
  readonly ent_type: string;
  topic_updates: EventEmitter<string>;

  publish_topics: (index: number) => string[];
  toJSON: () => { [key: string]: string | {} };
}

export function hash(str: string, digits: number = 5): string {
  let seed = cyrb128(str);
  let rand = sfc32(seed[0], seed[1], seed[2], seed[3]);
  let rand_num = Math.floor(rand() * 10 ** digits).toString();
  return rand_num;
}

function cyrb128(str: string) {
  let h1 = 1779033703,
    h2 = 3144134277,
    h3 = 1013904242,
    h4 = 2773480762;
  for (let i = 0, k; i < str.length; i++) {
    k = str.charCodeAt(i);
    h1 = h2 ^ Math.imul(h1 ^ k, 597399067);
    h2 = h3 ^ Math.imul(h2 ^ k, 2869860233);
    h3 = h4 ^ Math.imul(h3 ^ k, 951274213);
    h4 = h1 ^ Math.imul(h4 ^ k, 2716044179);
  }
  h1 = Math.imul(h3 ^ (h1 >>> 18), 597399067);
  h2 = Math.imul(h4 ^ (h2 >>> 22), 2869860233);
  h3 = Math.imul(h1 ^ (h3 >>> 17), 951274213);
  h4 = Math.imul(h2 ^ (h4 >>> 19), 2716044179);
  (h1 ^= h2 ^ h3 ^ h4), (h2 ^= h1), (h3 ^= h1), (h4 ^= h1);
  return [h1 >>> 0, h2 >>> 0, h3 >>> 0, h4 >>> 0];
}

function sfc32(a: number, b: number, c: number, d: number) {
  return function () {
    a |= 0;
    b |= 0;
    c |= 0;
    d |= 0;
    let t = (((a + b) | 0) + d) | 0;
    d = (d + 1) | 0;
    a = b ^ (b >>> 9);
    b = (c + (c << 3)) | 0;
    c = (c << 21) | (c >>> 11);
    c = (c + t) | 0;
    return (t >>> 0) / 4294967296;
  };
}