<?php

declare(strict_types=1);

namespace OCA\WorkflowDeckAutomation\Tests\Unit\Service;

use DateTimeImmutable;
use DateTimeZone;
use OCA\WorkflowDeckAutomation\Service\WorkflowRunner;
use PHPUnit\Framework\TestCase;

class WorkflowRunnerTest extends TestCase {
	private static function utc(string $time): DateTimeImmutable {
		return new DateTimeImmutable($time, new DateTimeZone('UTC'));
	}

	public function testIsOverdueReturnsFalseWithoutDueDate(): void {
		$this->assertFalse(WorkflowRunner::isOverdue(null, self::utc('2026-01-15 12:00:00')));
	}

	public function testIsOverdueReturnsFalseForFutureDueDate(): void {
		$now = self::utc('2026-01-15 12:00:00');
		$this->assertFalse(WorkflowRunner::isOverdue($now->modify('+1 hour'), $now));
		$this->assertFalse(WorkflowRunner::isOverdue($now->modify('+3 days'), $now));
	}

	public function testIsOverdueReturnsTrueForPastDueDate(): void {
		$now = self::utc('2026-01-15 12:00:00');
		$this->assertTrue(WorkflowRunner::isOverdue($now->modify('-1 hour'), $now));
		$this->assertTrue(WorkflowRunner::isOverdue($now->modify('-30 days'), $now));
	}

	public function testIsOverdueReturnsTrueForADueTimeEarlierTheSameDay(): void {
		// Regression: comparing whole calendar days (as Deck's own
		// Card::getDaysUntilDue() does) reports a card due earlier today as
		// "0 days until due", not overdue, until the calendar date rolls
		// over - holding every card back for up to 24h after it actually
		// fell due. isOverdue() must compare the real timestamps instead.
		$now = self::utc('2026-01-15 12:00:00');
		$this->assertTrue(WorkflowRunner::isOverdue(self::utc('2026-01-15 06:00:00'), $now));
	}

	public function testIsOverdueReadsTheStoredWallClockAsUtc(): void {
		// What Entity hydration produces if PHP's default zone is not UTC:
		// the stored UTC wall clock "12:00", tagged with the local zone.
		$due = new DateTimeImmutable('2026-07-15 12:00:00', new DateTimeZone('Europe/Berlin'));

		// Taken at face value that would be 10:00 UTC and already overdue.
		$this->assertFalse(WorkflowRunner::isOverdue($due, self::utc('2026-07-15 11:30:00')));
		$this->assertTrue(WorkflowRunner::isOverdue($due, self::utc('2026-07-15 12:00:01')));
	}

	public function testIsOverdueComparesNowAsAnAbsoluteInstant(): void {
		$due = self::utc('2026-07-15 12:00:00');
		$berlin = new DateTimeZone('Europe/Berlin');

		// 13:30 in Berlin (CEST) is 11:30 UTC - not yet due.
		$this->assertFalse(WorkflowRunner::isOverdue($due, new DateTimeImmutable('2026-07-15 13:30:00', $berlin)));
		// 14:30 in Berlin is 12:30 UTC - due.
		$this->assertTrue(WorkflowRunner::isOverdue($due, new DateTimeImmutable('2026-07-15 14:30:00', $berlin)));
	}

	public function testIsOverdueIsFalseAtTheExactDueInstant(): void {
		$now = self::utc('2026-01-15 12:00:00');
		$this->assertFalse(WorkflowRunner::isOverdue($now, $now));
	}
}