import { RandomEngine } from "./RandomEngine";
import { JSRandomEngine } from "./JSRandomEngine";

export class RandomUIDGenerator
{ 
  static readonly UID_CHARACTER_SET:string = 
    "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";

  static readonly UID_NUM_CHARACTERS:number = 16;
  
  private _characterSet:string = RandomUIDGenerator.UID_CHARACTER_SET;
  get characterSet(){ return this._characterSet; }

  private _numCharacters:number = RandomUIDGenerator.UID_NUM_CHARACTERS;
  get numCharacters(){ return this._numCharacters; }
  
  set( characterSet:string, numCharacters:number )
  {
    this._characterSet  = characterSet;
    this._numCharacters = numCharacters;
    
    return this;
  }



  static createUID( randomEngine:RandomEngine = null )
  {
    let id = "";
    randomEngine = randomEngine ||JSRandomEngine.$;
    
    for ( let i = 0; i < RandomUIDGenerator.UID_NUM_CHARACTERS; i++ )
    {
      let randomCharacter = randomEngine.fromString( RandomUIDGenerator.UID_CHARACTER_SET ); 
      id += randomCharacter;
    }

    return id;
  }
  
  generate( randomEngine:RandomEngine = null )
  { 
    let id = "";
    randomEngine = randomEngine || JSRandomEngine.$;
    
    for ( let i = 0; i < this._numCharacters; i++ )
    {
      let randomCharacter = randomEngine.fromString( this._characterSet ); 
      id += randomCharacter;
    }

    return id;
  }
}