library-ts/browser/expressions/AsyncStringMatcher.ts

import { AsyncBooleanExpression } from "./AsyncBooleanExpression";

export abstract class StringValueAsyncMatcher<T> extends AsyncBooleanExpression<T>
{
  abstract getStringValue( t:T ):Promise<string>; 
}

export abstract class LitaralAsyncMatcher<T,L extends string> extends StringValueAsyncMatcher<T>
{
  _literal:L 
  constructor( literal:L )
  {
    super();
    this._literal = literal;
  }

  async evaluate( t:T ):Promise<boolean>
  {

    let value = await this.getStringValue( t );

    if ( value === null )
    {
      return false;
    }

    return Promise.resolve( this._literal === value );
  } 
}

export abstract class ContainsLitaralAsyncMatcher<T,L extends string> extends StringValueAsyncMatcher<T>
{
  _literal:L 
  constructor( literal:L )
  {
    super();
    this._literal = literal;
  }

  async evaluate( t:T ):Promise<boolean>
  {

    let value = await this.getStringValue( t );

    if ( value === null )
    {
      return false;
    }

    return Promise.resolve( value.indexOf( this._literal ) !== -1 );
  } 
}

export abstract class RegExpAsyncMatcher<T> extends StringValueAsyncMatcher<T>
{
  private _regexp:RegExp;
  
  constructor( regexp:RegExp )
  {
    super();
    this._regexp = regexp;
  }

  async evaluate( t:T ):Promise<boolean>
  {
    let value = await this.getStringValue( t );

    if ( value === null )
    {
      return false;
    }
    
    return Promise.resolve( this._regexp.test( value ) );
  } 
  
}