ElementMap.js

"use strict";

class ElementMap {
  constructor( data ) {
    this._map = new Map();
    this._keyToElement = new Map();
    this.size = data ? data.length : 0;
    if ( data ) {
      data.forEach( d => this._map.set( d[ 0 ], d[ 1 ] ) );
    }
  }

  getElement( key ) {
    return this._keyToElement.get( key );
  }

  /* Callbacks */
  /* ........................................................................ */
  connect( obj ) {
    this._root = obj.root;
    this._item = obj.item;
    this._onset = obj.onset || this._defOnset;
    this._ondel = obj.ondelete || this._defOndel;
    this._map.forEach( ( val, key ) => this._set( key, val ) );
  }
  _defOnset( elem, val, key ) {
    return val;
  }
  _defOndel( elem ) {
    elem.remove();
  }

  /* Map overwrite */
  /* ........................................................................ */
  forEach( fn ) {
    this._map.forEach( ( val, key ) => {
      fn( this._keyToElement.get( key ), val, key );
    } );
  }
  has( key ) {
    return this._map.has( key );
  }
  get( key ) {
    return this._map.get( key );
  }
  set( key, val ) {
    const has = this._map.has( key );

    if ( !has ) {
      ++this.size;
    }
    this._map.set( key, has
        ? this._onset( this._keyToElement.get( key ), val, key )
        : this._set( key, val ) );
  }
  _set( key, val ) {
    const elem = this._item.cloneNode( true ),
      _ = this._keyToElement.set( key, elem ),
      val2 = this._onset( elem, val, key );

    this._root.append( elem );
    return val2;
  }
  delete( key ) {
    const elem = this._keyToElement.get( key );

    if ( elem ) {
      --this.size;
      this._map.delete( key );
      this._keyToElement.delete( key );
      this._ondel( elem, key );
    }
  }
  clear() {
    this._map.forEach( ( val, key ) => {
      --this.size;
      this._ondel( this._keyToElement.get( key ), key );
    } );
    this._keyToElement.clear();
    this._map.clear();
  }
}