<?php

namespace Tests\Unit\Helpers;

use App\Helpers\DateHelper;
use Carbon\Carbon;
use Carbon\Exceptions\InvalidDateException;
use PHPUnit\Framework\TestCase;

class DateHelperTest extends TestCase
{
    protected function setUp(): void
    {
        parent::setUp();
        Carbon::setLocale('ru');
    }

    public function test_excel_date_to_iso_date_converts_correctly(): void
    {
        // Excel date 44927 = 2023-01-01
        $this->assertEquals('2023-01-01', DateHelper::excelDateToISODate(44927));

        // Excel date 45292 = 2024-01-01
        $this->assertEquals('2024-01-01', DateHelper::excelDateToISODate(45292));

        // Excel date 25569 = 1970-01-01 (Unix epoch)
        $this->assertEquals('1970-01-01', DateHelper::excelDateToISODate(25569));
    }

    public function test_iso_date_to_excel_date_converts_correctly(): void
    {
        $this->assertEquals(44927, DateHelper::ISODateToExcelDate('2023-01-01'));
        $this->assertEquals(45292, DateHelper::ISODateToExcelDate('2024-01-01'));
        $this->assertEquals(25569, DateHelper::ISODateToExcelDate('1970-01-01'));
    }

    public function test_excel_date_conversion_is_reversible(): void
    {
        $excelDate = 45000;
        $isoDate = DateHelper::excelDateToISODate($excelDate);
        $backToExcel = DateHelper::ISODateToExcelDate($isoDate);

        $this->assertEquals($excelDate, $backToExcel);
    }

    public function test_get_human_date_returns_text_format_by_default(): void
    {
        $result = DateHelper::getHumanDate('2024-03-15');

        // Should contain month name in Russian
        $this->assertStringContainsString('марта', $result);
        $this->assertStringContainsString('15', $result);
        $this->assertStringContainsString('2024', $result);
    }

    public function test_get_human_date_returns_numeric_format_when_requested(): void
    {
        $result = DateHelper::getHumanDate('2024-03-15', true);

        $this->assertEquals('15.03.2024', $result);
    }

    public function test_is_date_validates_correct_dates(): void
    {
        $this->assertTrue(DateHelper::isDate('2024-01-01'));
        $this->assertTrue(DateHelper::isDate('2023-12-31'));
        $this->assertTrue(DateHelper::isDate('1990-06-15'));
    }

    public function test_is_date_rejects_invalid_dates(): void
    {
        $this->assertFalse(DateHelper::isDate('2024-13-01')); // Invalid month
        $this->assertFalse(DateHelper::isDate('2024-00-01')); // Invalid month
        $this->assertFalse(DateHelper::isDate('2024-01-32')); // Invalid day
        $this->assertFalse(DateHelper::isDate('24-01-01'));   // Short year
        $this->assertFalse(DateHelper::isDate('01-01-2024')); // Wrong format
        $this->assertFalse(DateHelper::isDate('not-a-date'));
    }

    public function test_get_date_for_db_formats_correctly(): void
    {
        $this->assertEquals('2024-03-15', DateHelper::getDateForDB('March 15, 2024'));
        $this->assertEquals('2024-03-15', DateHelper::getDateForDB('15.03.2024'));
    }

    public function test_add_months_works_correctly(): void
    {
        $this->assertEquals('2024-04-01', DateHelper::addMonths('2024-01-01', 3));
        $this->assertEquals('2025-01-01', DateHelper::addMonths('2024-01-01', 12));
        $this->assertEquals('2023-10-01', DateHelper::addMonths('2024-01-01', -3));
    }

    public function test_get_date_of_week_returns_correct_date(): void
    {
        // Week 1 of 2024, Monday
        $result = DateHelper::getDateOfWeek(2024, 1, 1);
        $this->assertEquals('2024-01-01', $result);

        // Week 1 of 2024, Sunday
        $result = DateHelper::getDateOfWeek(2024, 1, 7);
        $this->assertEquals('2024-01-07', $result);
    }

    public function test_get_random_date_returns_valid_date(): void
    {
        $result = DateHelper::getRandomDate(1);

        $this->assertTrue(DateHelper::isDate($result));
    }

    public function test_get_random_date_throws_exception_for_invalid_years(): void
    {
        $this->expectException(InvalidDateException::class);
        DateHelper::getRandomDate(-1);
    }

    public function test_get_human_day_of_week_returns_russian_day_name(): void
    {
        // 2024-01-01 is Monday
        $result = DateHelper::getHumanDayOfWeek('2024-01-01');
        $this->assertEquals('Понедельник', $result);

        // 2024-01-07 is Sunday
        $result = DateHelper::getHumanDayOfWeek('2024-01-07');
        $this->assertEquals('Воскресенье', $result);
    }
}