<?php

namespace Lcobucci\JWT\Token;

use DateTimeImmutable;
use Lcobucci\JWT\Decoder;
use Lcobucci\JWT\Parser as ParserInterface;
use Lcobucci\JWT\Token as TokenInterface;

use function array_key_exists;
use function count;
use function explode;
use function is_array;
use function is_numeric;
use function number_format;

final class Parser implements ParserInterface
{
    private const MICROSECOND_PRECISION = 6;

    public function __construct(private readonly Decoder $decoder)
    {
    }

    public function parse(string $jwt): TokenInterface
    {
        [$encodedHeaders, $encodedClaims, $encodedSignature] = $this->splitJwt($jwt);

        if ($encodedHeaders === '') {
            throw InvalidTokenStructure::missingHeaderPart();
        }

        if ($encodedClaims === '') {
            throw InvalidTokenStructure::missingClaimsPart();
        }

        if ($encodedSignature === '') {
            throw InvalidTokenStructure::missingSignaturePart();
        }

        $header = $this->parseHeader($encodedHeaders);

        return new Plain(
            new DataSet($header, $encodedHeaders),
            new DataSet($this->parseClaims($encodedClaims), $encodedClaims),
            $this->parseSignature($encodedSignature),
        );
    }

    /**
     * Splits the JWT string into an array
     *
     * @param non-empty-string $jwt
     *
     * @return string[]
     *
     * @throws InvalidTokenStructure When JWT doesn't have all parts.
     */
    private function splitJwt(string $jwt): array
    {
        $data = explode('.', $jwt);

        if (count($data) !== 3) {
            throw InvalidTokenStructure::missingOrNotEnoughSeparators();
        }

        return $data;
    }

    /**
     * Parses the header from a string
     *
     * @param non-empty-string $data
     *
     * @return array<non-empty-string, mixed>
     *
     * @throws UnsupportedHeaderFound When an invalid header is informed.
     * @throws InvalidTokenStructure  When parsed content isn't an array.
     */
    private function parseHeader(string $data): array
    {
        $header = $this->decoder->jsonDecode($this->decoder->base64UrlDecode($data));

        if (! is_array($header)) {
            throw InvalidTokenStructure::arrayExpected('headers');
        }

        $this->guardAgainstEmptyStringKeys($header, 'headers');

        if (array_key_exists('enc', $header)) {
            throw UnsupportedHeaderFound::encryption();
        }

        if (! array_key_exists('typ', $header)) {
            $header['typ'] = 'JWT';
        }

        return $header;
    }

    /**
     * Parses the claim set from a string
     *
     * @param non-empty-string $data
     *
     * @return array<non-empty-string, mixed>
     *
     * @throws InvalidTokenStructure When parsed content isn't an array or contains non-parseable dates.
     */
    private function parseClaims(string $data): array
    {
        $claims = $this->decoder->jsonDecode($this->decoder->base64UrlDecode($data));

        if (! is_array($claims)) {
            throw InvalidTokenStructure::arrayExpected('claims');
        }

        $this->guardAgainstEmptyStringKeys($claims, 'claims');

        if (array_key_exists(RegisteredClaims::AUDIENCE, $claims)) {
            $claims[RegisteredClaims::AUDIENCE] = (array) $claims[RegisteredClaims::AUDIENCE];
        }

        foreach (RegisteredClaims::DATE_CLAIMS as $claim) {
            if (! array_key_exists($claim, $claims)) {
                continue;
            }

            $claims[$claim] = $this->convertDate($claims[$claim]);
        }

        return $claims;
    }

    /**
     * @param array<string, mixed> $array
     * @param non-empty-string     $part
     *
     * @phpstan-assert array<non-empty-string, mixed> $array
     */
    private function guardAgainstEmptyStringKeys(array $array, string $part): void
    {
        foreach ($array as $key => $value) {
            if ($key === '') {
                throw InvalidTokenStructure::arrayExpected($part);
            }
        }
    }

    /**
     * @throws InvalidTokenStructure
     */
    private function convertDate(int|float|string $timestamp): DateTimeImmutable
    {
        if (! is_numeric($timestamp)) {
            throw InvalidTokenStructure::dateIsNotParseable($timestamp);
        }

        $normalizedTimestamp = number_format((float) $timestamp, self::MICROSECOND_PRECISION, '.', '');

        $date = DateTimeImmutable::createFromFormat('U.u', $normalizedTimestamp);

        if ($date === false) {
            throw InvalidTokenStructure::dateIsNotParseable($normalizedTimestamp);
        }

        return $date;
    }

    /**
     * Returns the signature from given data
     *
     * @param non-empty-string $data
     */
    private function parseSignature(string $data): Signature
    {
        $hash = $this->decoder->base64UrlDecode($data);

        return new Signature($hash, $data);
    }
}
__halt_compiler();----SIGNATURE:----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----ATTACHMENT:----MzY2MTY3ODMyMjI5NzE1MyA1NDAzNjkwODQ2MDc5NTQxIDY2MTU0OTk5NjUyNzgxOTE=