<?php

declare(strict_types=1);

namespace LIT\MCP\Tests\Unit\Integrations\Divi\BlockTree;

use JsonException;
use LIT\MCP\Integrations\Divi\BlockTree\Json;
use PHPUnit\Framework\TestCase;
use stdClass;

final class JsonTest extends TestCase
{
    public function testDecodesAPlainObject(): void
    {
        self::assertSame(['a' => 1], Json::decodeObject('{"a":1}'));
        self::assertSame([], Json::decodeObject('{}'));
    }

    public function testRejectsNonObjectTopLevelJson(): void
    {
        self::assertNull(Json::decodeObject('[1,2,3]'));
        self::assertNull(Json::decodeObject('"a string"'));
        self::assertNull(Json::decodeObject('not json'));
    }

    /** A JSON object whose keys are "0", "1", … decodes to a PHP list – re-encoding it would
     *  silently turn it back into a JSON array (Json.php docblock, EmptyArrayCorruptionMigration). */
    public function testTreatsAListLikeTopLevelObjectAsOpaqueRatherThanAnArray(): void
    {
        self::assertNull(Json::decodeObject('{"0":"a","1":"b"}'));
        self::assertNull(Json::decodeObject('{"0":"a"}'));
    }

    public function testDoesNotFlagAGenuineObjectWithNonSequentialNumericKeys(): void
    {
        self::assertSame(['0' => 'a', '2' => 'b'], Json::decodeObject('{"0":"a","2":"b"}'));
    }

    public function testEncodeThrowsOnInvalidUtf8(): void
    {
        $this->expectException(JsonException::class);

        Json::encode("\xB1\x31");
    }

    public function testEncodeRoundtripsAnEmptyObject(): void
    {
        self::assertSame('{}', Json::encode(new stdClass()));
    }
}