/home/kueuepay/public_html/vendor/egulias/email-validator/src/Parser/LocalPart.php
<?php

namespace Egulias\EmailValidator\Parser;

use Egulias\EmailValidator\EmailLexer;
use Egulias\EmailValidator\Result\Result;
use Egulias\EmailValidator\Result\ValidEmail;
use Egulias\EmailValidator\Result\InvalidEmail;
use Egulias\EmailValidator\Warning\LocalTooLong;
use Egulias\EmailValidator\Result\Reason\DotAtEnd;
use Egulias\EmailValidator\Result\Reason\DotAtStart;
use Egulias\EmailValidator\Result\Reason\ConsecutiveDot;
use Egulias\EmailValidator\Result\Reason\ExpectingATEXT;
use Egulias\EmailValidator\Parser\CommentStrategy\LocalComment;

class LocalPart extends PartParser
{
    public const INVALID_TOKENS = [
        EmailLexer::S_COMMA => EmailLexer::S_COMMA,
        EmailLexer::S_CLOSEBRACKET => EmailLexer::S_CLOSEBRACKET,
        EmailLexer::S_OPENBRACKET => EmailLexer::S_OPENBRACKET,
        EmailLexer::S_GREATERTHAN => EmailLexer::S_GREATERTHAN,
        EmailLexer::S_LOWERTHAN => EmailLexer::S_LOWERTHAN,
        EmailLexer::S_COLON => EmailLexer::S_COLON,
        EmailLexer::S_SEMICOLON => EmailLexer::S_SEMICOLON,
        EmailLexer::INVALID => EmailLexer::INVALID
    ];

    /**
     * @var string
     */
    private $localPart = '';


    public function parse() : Result
    {
        $this->lexer->startRecording();

        while (((array) $this->lexer->token)['type'] !== EmailLexer::S_AT && null !== ((array) $this->lexer->token)['type']) {
            if ($this->hasDotAtStart()) {
                return new InvalidEmail(new DotAtStart(), ((array) $this->lexer->token)['value']);
            }

            if (((array) $this->lexer->token)['type'] === EmailLexer::S_DQUOTE) {
                $dquoteParsingResult = $this->parseDoubleQuote();

                //Invalid double quote parsing
                if($dquoteParsingResult->isInvalid()) {
                    return $dquoteParsingResult;
                }
            }

            if (((array) $this->lexer->token)['type'] === EmailLexer::S_OPENPARENTHESIS ||
                ((array) $this->lexer->token)['type'] === EmailLexer::S_CLOSEPARENTHESIS ) {
                $commentsResult = $this->parseComments();

                //Invalid comment parsing
                if($commentsResult->isInvalid()) {
                    return $commentsResult;
                }
            }

            if (((array) $this->lexer->token)['type'] === EmailLexer::S_DOT && $this->lexer->isNextToken(EmailLexer::S_DOT)) {
                return new InvalidEmail(new ConsecutiveDot(), ((array) $this->lexer->token)['value']);
            }

            if (((array) $this->lexer->token)['type'] === EmailLexer::S_DOT &&
                $this->lexer->isNextToken(EmailLexer::S_AT)
            ) {
                return new InvalidEmail(new DotAtEnd(), ((array) $this->lexer->token)['value']);
            }

            $resultEscaping = $this->validateEscaping();
            if ($resultEscaping->isInvalid()) {
                return $resultEscaping;
            }

            $resultToken = $this->validateTokens(false);
            if ($resultToken->isInvalid()) {
                return $resultToken;
            }

            $resultFWS = $this->parseLocalFWS();
            if($resultFWS->isInvalid()) {
                return $resultFWS;
            }

            $this->lexer->moveNext();
        }

        $this->lexer->stopRecording();
        $this->localPart = rtrim($this->lexer->getAccumulatedValues(), '@');
        if (strlen($this->localPart) > LocalTooLong::LOCAL_PART_LENGTH) {
            $this->warnings[LocalTooLong::CODE] = new LocalTooLong();
        }

        return new ValidEmail();
    }

    protected function validateTokens(bool $hasComments) : Result
    {
        if (isset(self::INVALID_TOKENS[((array) $this->lexer->token)['type']])) {
            return new InvalidEmail(new ExpectingATEXT('Invalid token found'), ((array) $this->lexer->token)['value']);
        }
        return new ValidEmail();
    }

    public function localPart() : string
    {
        return $this->localPart;
    }

    private function parseLocalFWS() : Result
    {
        $foldingWS = new FoldingWhiteSpace($this->lexer);
        $resultFWS = $foldingWS->parse();
        if ($resultFWS->isValid()) {
            $this->warnings = array_merge($this->warnings, $foldingWS->getWarnings());
        }
        return $resultFWS;
    }

    private function hasDotAtStart() : bool
    {
            return ((array) $this->lexer->token)['type'] === EmailLexer::S_DOT && null === $this->lexer->getPrevious()['type'];
    }

    private function parseDoubleQuote() : Result
    {
        $dquoteParser = new DoubleQuote($this->lexer);
        $parseAgain = $dquoteParser->parse();
        $this->warnings = array_merge($this->warnings, $dquoteParser->getWarnings());

        return $parseAgain;
    }

    protected function parseComments(): Result
    {
        $commentParser = new Comment($this->lexer, new LocalComment());
        $result = $commentParser->parse();
        $this->warnings = array_merge($this->warnings, $commentParser->getWarnings());
        if($result->isInvalid()) {
            return $result;
        }
        return $result;
    }

    private function validateEscaping() : Result
    {
        //Backslash found
        if (((array) $this->lexer->token)['type'] !== EmailLexer::S_BACKSLASH) {
            return new ValidEmail();
        }

        if ($this->lexer->isNextToken(EmailLexer::GENERIC)) {
            return new InvalidEmail(new ExpectingATEXT('Found ATOM after escaping'), ((array) $this->lexer->token)['value']);
        }

        if (!$this->lexer->isNextTokenAny(array(EmailLexer::S_SP, EmailLexer::S_HTAB, EmailLexer::C_DEL))) {
            return new ValidEmail();
        }

        return new ValidEmail();
    }
}
Best Practice

Best Practices

To ensure a smooth integration process and optimal performance, follow these best practices:

  1. Use secure HTTPS connections for all API requests.
  2. Implement robust error handling to handle potential issues gracefully.
  3. Regularly update your integration to stay current with any API changes or enhancements.