import { NgModule, Pipe, PipeTransform } from '@angular/core';

/**
 * Generated class for the FormatPipe pipe.
 *
 * See https://angular.io/api/core/Pipe for more info on Angular Pipes.
 *
 * @example
 * ``` html
 * {{ cpf | format:'999.999.999-99' }}
 * {{ tel | format:'(99) 9 9999-9999' }}
 * ```
 */
@Pipe({
  name: 'format'
})
export class FormatPipe implements PipeTransform {

  /**
   * Format value.
   *
   * @param  {any}    value    Waits to receive string or integer
   * @param  {string} pattern  Waits to receive a pattern in string
   * @return {[type]}          returns a formatted string.
   */
  transform(value: any, pattern: string) {
    return this.format(String(value), pattern);
  }

  /**
   * Format value
   * @param  {string} value   virgin value.
   * @param  {string} pattern standard format.
   * @return {string}         returns a formatted string.
   */
  private format(value: string, pattern: string): string {
    let data: string = '', cont: number = 0, plus: string = '';

    for (let i = 0; i < pattern.length; i++) {
      if (parseInt(pattern[i])) {
        cont++
      }
    }

    /**
     * Addes zeros to the left to complete the characters in the format.
     */
    if (cont > value.length) {
      for (let i = 0; i < cont - value.length; i++) {
        plus = plus.concat('0')
      }
      value = plus + value
    }

    cont = 0

    /**
     * Replaces pattern numbers with values.
     */
    for (let i = 0; i < pattern.length; i++) {
      if (parseInt(pattern[i]) && cont < value.length) {
        data = data.concat(value[cont])
        cont++
      } else {
        data = data.concat(pattern[i])
      }
    }
    return data
  }
}

@NgModule({
  declarations: [FormatPipe],
  exports: [FormatPipe]
})
export class FormatPipeModule {}