<?php

namespace App\Services\Sgc;

use DateTimeImmutable;
use DateTimeZone;
use Generator;
use InvalidArgumentException;

final class CalendarDimension
{
    /** Weekdays are a calendar approximation, not an official holiday calendar. */
    public static function days(int $startYear, int $years): Generator
    {
        if ($startYear < 1 || $years < 1 || $years > 100 || $startYear + $years > 10000) throw new InvalidArgumentException('Invalid calendar interval.');
        $months = [1=>'Janeiro','Fevereiro','Março','Abril','Maio','Junho','Julho','Agosto','Setembro','Outubro','Novembro','Dezembro'];
        $weekdays = [1=>'Segunda','Terça','Quarta','Quinta','Sexta','Sábado','Domingo'];
        $date = new DateTimeImmutable(sprintf('%04d-01-01', $startYear), new DateTimeZone('Africa/Maputo'));
        while ((int)$date->format('Y') < $startYear + $years) {
            $month = (int)$date->format('n'); $weekday = (int)$date->format('N');
            yield ['data_id'=>(int)$date->format('Ymd'), 'data_completa'=>$date->format('Y-m-d'),
                'dia_semana'=>$weekday, 'nome_dia_semana'=>$weekdays[$weekday], 'dia_mes'=>(int)$date->format('j'),
                'mes'=>$month, 'nome_mes'=>$months[$month], 'trimestre'=>intdiv($month-1,3)+1,
                'ano'=>(int)$date->format('Y'), 'ano_mes'=>$date->format('Y-m'),
                'eh_dia_util'=>$weekday<=5, 'eh_feriado'=>false, 'semestre'=>$month<=6?1:2];
            $date = $date->modify('+1 day');
        }
    }
}