import { Injectable } from '@angular/core';
import { ValidatorFn } from '@angular/forms';
import { ComplexValidatorOptions } from '../../interfaces';

type simpleValidatorFn = (value: string) => boolean;

@Injectable()
export class ValidatorBuilder {

  simpleValidator(validator: simpleValidatorFn, errorMessage: string = 'unknown error'): ValidatorFn {
    return function({value}){
      return validator(value) ? null : {error: errorMessage}
    }
  }

  complexValidator(options: ComplexValidatorOptions, errorMessage: string = 'unknown error'): ValidatorFn {

    const {digits,lowercase,uppercase} = options;

    return function(control){

      const value: string = control.value;
      const tests = [];

      const digitReg = new RegExp(/\d/g)
      const lowercaseReg = new RegExp(/[a-z]/g)
      const uppercaseReg = new RegExp(/[A-Z]/g)
  
      digits.required && tests.push(digitReg.test(value));
      digits.min && tests.push((value.match(digitReg) || []).length >= digits.min)
      digits.max && tests.push((value.match(digitReg) || []).length <= digits.max)

      lowercase.required && tests.push(lowercaseReg.test(value));
      lowercase.min && tests.push((value.match(lowercaseReg) || []).length >= lowercase.min)
      lowercase.max && tests.push((value.match(lowercaseReg) || []).length <= lowercase.max)

      uppercase.required && tests.push(uppercaseReg.test(value));
      uppercase.min && tests.push((value.match(uppercaseReg) || []).length >= uppercase.min)
      uppercase.max && tests.push((value.match(uppercaseReg) || []).length <= uppercase.max);

      console.log(tests);

      const isPassed = tests.every(result => result);
      return isPassed ? null : {error: errorMessage};

    }
  }  
}