import {Component} from '@angular/core';
import {ControlGroup, Control, Validators, FormBuilder} from '@angular/common'
import {UsernameValidators} from './usernameValidators'

@Component({
selector: 'signup',
templateUrl: 'signup-component.html'

})


export class SignupComponent{
  form: ControlGroup;
  constructor(fb: FormBuilder){
  this.form = fb.group({
username:['', Validators.compose([
  Validators.required, UsernameValidators.cannotContainSpace
])],
password: ['', Validators.required]


  })

}
}

import {Control} from '@angular/common'


export class UsernameValidators{

static shouldBeUnique(control: Control){
return new Promise((resolve, reject) => {
setTimeout(function(){
if(control.value == "andy")
resolve({shouldBeUnique: true});
else
resolve(null);
}, 1000);

});

}


static cannotContainSpace(control: Control){
if (control.value.indexOf(' ') >= 0)
return {cannotContainSpace: true};

return null;



}


}