import { LocalDate, Month } from 'js-joda';
import * as _ from 'lodash';

export function DOBPickerDirectiveFactory() {
  return new DOBPickerDirective();
}

class DOBPickerDirective implements ng.IDirective {
  restrict = 'E';
  bindToController = true;
  controller = DOBPickerController;
  controllerAs = 'ctrl';
  template = require<string>('./DOBPicker.html');
  scope = {
    name: '@',
    label: '@',
    dateOfBirth: '='
  }
}

export class DOBPickerController {
  maxYear: number;
  months: string[];
  maxDays: number;

  dateOfBirth: LocalDate;
  selectedYear: number;
  selectedMonth: number;
  selectedDay: number;

  constructor() {
    this.maxDays = 31;
    this.maxYear = LocalDate.now().year();
    this.months = Month.values().map(m => _.upperFirst(m.toString().toLowerCase()));

    // Initialise fields using initial value
    if (this.dateOfBirth) {
      this.selectedDay = this.dateOfBirth.dayOfMonth();
      this.selectedMonth = this.dateOfBirth.monthValue();
      this.selectedYear = this.dateOfBirth.year();
    }
  }

  update() {
    if (this.selectedMonth && this.selectedYear) {
      this.maxDays = LocalDate.of(this.selectedYear, this.selectedMonth, 1).lengthOfMonth();
    } else {
      this.maxDays = 31;
    }

    if (this.selectedDay > this.maxDays) {
      this.selectedDay = this.maxDays;
    }

    if (this.selectedDay && this.selectedMonth && this.selectedYear) {
      this.dateOfBirth = LocalDate.of(this.selectedYear, this.selectedMonth, this.selectedDay);
    } else {
      delete this.dateOfBirth;
    }
  }
}