/* eslint-disable no-unused-expressions */

import { TheoryCheck } from "../../util/TheoryCheck";

/**
 * @class YYMParse musicxml 解析
 */
export class TheoryParse {
  // 默认初始化 unit64, 代表一个 64 分音符所在的 占用的 时长
  private _xmlDOM: Document;
  private _time: HTMLCollectionOf<Element>;
  private _octaveShifts: HTMLCollectionOf<Element>;
  private _measures: HTMLCollectionOf<Element>;
  private _notes: HTMLCollectionOf<Element>;
  private _print: HTMLCollectionOf<Element>;
  private _attribute: HTMLCollectionOf<Element>;
  private _part: HTMLCollectionOf<Element>;
  private _measureBackupDuration: number[];
  // 4 分音符的持续时间
  private _divisions: number;
  public constructor(xmlDOM_: Document) {
    this._xmlDOM = xmlDOM_;
    // remove words  on music sheet (such as " Moderato " , "Allegretto")
    this.removeWords();
  }

  private removeWords() {
    let directionWords = this._xmlDOM.getElementsByTagName("words");
    while (!TheoryCheck.isEmptyArray(directionWords)) {
      directionWords[0]?.parentNode?.removeChild(directionWords[0]);
    }
  }

  public getMusicxmlDOM() {
    return this._xmlDOM;
  }

  public setMusicxmlDOM(value: Document) {
    this._xmlDOM = value;
  }

  public getXMLNoteList(): HTMLCollectionOf<Element> {
    return this._xmlDOM.getElementsByTagName("note");
  }

  public getClefBeats() {
    if (TheoryCheck.isNullOrUndefined(this._time)) {
      this._time = this._xmlDOM.getElementsByTagName("time");
    }
    return parseInt(this._time[0].getElementsByTagName("beats")[0].innerHTML, 10);
  }

  public getBeatsType() {
    if (TheoryCheck.isNullOrUndefined(this._time)) {
      this._time = this._xmlDOM.getElementsByTagName("time");
    }
    return parseInt(this._time[0].getElementsByTagName("beat-type")[0].innerHTML, 10);
  }
  public getOctaveShift() {
    if (TheoryCheck.isNullOrUndefined(this._octaveShifts)) {
      this._octaveShifts = this._xmlDOM.getElementsByTagName("octave-shift");
    }
    return this._octaveShifts;
  }

  public getMeasures() {
    if (TheoryCheck.isNullOrUndefined(this._measures)) {
      this._measures = this._xmlDOM.getElementsByTagName("measure");
    }
    return this._measures;
  }

  public getNotes() {
    if (TheoryCheck.isNullOrUndefined(this._notes)) {
      this._notes = this._xmlDOM.getElementsByTagName("note");
    }
    return this._notes;
  }
  public getPrint() {
    if (TheoryCheck.isNullOrUndefined(this._print)) {
      this._print = this.getMeasures()[0].getElementsByTagName("print");
    }
    return this._print;
  }

  public getAttributes() {
    if (TheoryCheck.isNullOrUndefined(this._attribute)) {
      this._attribute = this.getMeasures()[0].getElementsByTagName("attributes");
    }
    return this._attribute;
  }

  public getPart() {
    if (TheoryCheck.isNullOrUndefined(this._part)) {
      this._part = this._xmlDOM.getElementsByTagName("part");
    }
    return this._part;
  }

  public getSpecificMeasureClef(index: number) {
    return this.getMeasures()[index].getElementsByTagName("clef");
  }

  public getMeasureBackupDuration(): number[] {
    if (TheoryCheck.isNullOrUndefined(this._measures)) {
      this._measures = this._xmlDOM.getElementsByTagName("measure");
    }
    if (TheoryCheck.isNullOrUndefined(this._measureBackupDuration)) {
      this._measureBackupDuration = [];
      // 获取每个小节的 backup 然后存起来
      for (let i = 0; i < this._measures.length; i++) {
        let backupDuration = parseInt(
          this._measures[i].getElementsByTagName("backup")[0].getElementsByTagName("duration")[0].innerHTML,
          10
        );
        this._measureBackupDuration.push(backupDuration);
      }
    }
    return this._measureBackupDuration;
  }

  public getDivisions(): number {
    if (TheoryCheck.isNullOrUndefined(this._measures)) {
      this._measures = this._xmlDOM.getElementsByTagName("measure");
    }
    if (this._divisions === undefined) {
      this._divisions = parseInt(this._measures[0].getElementsByTagName("divisions")[0].innerHTML, 10);
    }
    return this._divisions;
  }
}