<?php

declare(strict_types=1);

namespace Doctrine\Common\Lexer;

use ReflectionClass;
use UnitEnum;

use function get_class;
use function implode;
use function preg_split;
use function sprintf;
use function substr;

use const PREG_SPLIT_DELIM_CAPTURE;
use const PREG_SPLIT_NO_EMPTY;
use const PREG_SPLIT_OFFSET_CAPTURE;

/**
 * Base class for writing simple lexers, i.e. for creating small DSLs.
 *
 * @template T of UnitEnum|string|int
 * @template V of string|int
 */
abstract class AbstractLexer
{
    /**
     * Lexer original input string.
     *
     * @var string
     */
    private $input;

    /**
     * Array of scanned tokens.
     *
     * @var list<Token<T, V>>
     */
    private $tokens = [];

    /**
     * Current lexer position in input string.
     *
     * @var int
     */
    private $position = 0;

    /**
     * Current peek of current lexer position.
     *
     * @var int
     */
    private $peek = 0;

    /**
     * The next token in the input.
     *
     * @var Token<T, V>|null
     */
    public $lookahead;

    /**
     * The last matched/seen token.
     *
     * @var Token<T, V>|null
     */
    public $token;

    /**
     * Composed regex for input parsing.
     *
     * @var non-empty-string|null
     */
    private $regex;

    /**
     * Sets the input data to be tokenized.
     *
     * The Lexer is immediately reset and the new input tokenized.
     * Any unprocessed tokens from any previous input are lost.
     *
     * @param string $input The input to be tokenized.
     *
     * @return void
     */
    public function setInput($input)
    {
        $this->input  = $input;
        $this->tokens = [];

        $this->reset();
        $this->scan($input);
    }

    /**
     * Resets the lexer.
     *
     * @return void
     */
    public function reset()
    {
        $this->lookahead = null;
        $this->token     = null;
        $this->peek      = 0;
        $this->position  = 0;
    }

    /**
     * Resets the peek pointer to 0.
     *
     * @return void
     */
    public function resetPeek()
    {
        $this->peek = 0;
    }

    /**
     * Resets the lexer position on the input to the given position.
     *
     * @param int $position Position to place the lexical scanner.
     *
     * @return void
     */
    public function resetPosition($position = 0)
    {
        $this->position = $position;
    }

    /**
     * Retrieve the original lexer's input until a given position.
     *
     * @param int $position
     *
     * @return string
     */
    public function getInputUntilPosition($position)
    {
        return substr($this->input, 0, $position);
    }

    /**
     * Checks whether a given token matches the current lookahead.
     *
     * @param T $type
     *
     * @return bool
     *
     * @psalm-assert-if-true !=null $this->lookahead
     */
    public function isNextToken($type)
    {
        return $this->lookahead !== null && $this->lookahead->isA($type);
    }

    /**
     * Checks whether any of the given tokens matches the current lookahead.
     *
     * @param list<T> $types
     *
     * @return bool
     *
     * @psalm-assert-if-true !=null $this->lookahead
     */
    public function isNextTokenAny(array $types)
    {
        return $this->lookahead !== null && $this->lookahead->isA(...$types);
    }

    /**
     * Moves to the next token in the input string.
     *
     * @return bool
     *
     * @psalm-assert-if-true !null $this->lookahead
     */
    public function moveNext()
    {
        $this->peek      = 0;
        $this->token     = $this->lookahead;
        $this->lookahead = isset($this->tokens[$this->position])
            ? $this->tokens[$this->position++] : null;

        return $this->lookahead !== null;
    }

    /**
     * Tells the lexer to skip input tokens until it sees a token with the given value.
     *
     * @param T $type The token type to skip until.
     *
     * @return void
     */
    public function skipUntil($type)
    {
        while ($this->lookahead !== null && ! $this->lookahead->isA($type)) {
            $this->moveNext();
        }
    }

    /**
     * Checks if given value is identical to the given token.
     *
     * @param string     $value
     * @param int|string $token
     *
     * @return bool
     */
    public function isA($value, $token)
    {
        return $this->getType($value) === $token;
    }

    /**
     * Moves the lookahead token forward.
     *
     * @return Token<T, V>|null The next token or NULL if there are no more tokens ahead.
     */
    public function peek()
    {
        if (isset($this->tokens[$this->position + $this->peek])) {
            return $this->tokens[$this->position + $this->peek++];
        }

        return null;
    }

    /**
     * Peeks at the next token, returns it and immediately resets the peek.
     *
     * @return Token<T, V>|null The next token or NULL if there are no more tokens ahead.
     */
    public function glimpse()
    {
        $peek       = $this->peek();
        $this->peek = 0;

        return $peek;
    }

    /**
     * Scans the input string for tokens.
     *
     * @param string $input A query string.
     *
     * @return void
     */
    protected function scan($input)
    {
        if (! isset($this->regex)) {
            $this->regex = sprintf(
                '/(%s)|%s/%s',
                implode(')|(', $this->getCatchablePatterns()),
                implode('|', $this->getNonCatchablePatterns()),
                $this->getModifiers()
            );
        }

        $flags   = PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_OFFSET_CAPTURE;
        $matches = preg_split($this->regex, $input, -1, $flags);

        if ($matches === false) {
            // Work around https://bugs.php.net/78122
            $matches = [[$input, 0]];
        }

        foreach ($matches as $match) {
            // Must remain before 'value' assignment since it can change content
            $firstMatch = $match[0];
            $type       = $this->getType($firstMatch);

            $this->tokens[] = new Token(
                $firstMatch,
                $type,
                $match[1]
            );
        }
    }

    /**
     * Gets the literal for a given token.
     *
     * @param T $token
     *
     * @return int|string
     */
    public function getLiteral($token)
    {
        if ($token instanceof UnitEnum) {
            return get_class($token) . '::' . $token->name;
        }

        $className = static::class;

        $reflClass = new ReflectionClass($className);
        $constants = $reflClass->getConstants();

        foreach ($constants as $name => $value) {
            if ($value === $token) {
                return $className . '::' . $name;
            }
        }

        return $token;
    }

    /**
     * Regex modifiers
     *
     * @return string
     */
    protected function getModifiers()
    {
        return 'iu';
    }

    /**
     * Lexical catchable patterns.
     *
     * @return string[]
     */
    abstract protected function getCatchablePatterns();

    /**
     * Lexical non-catchable patterns.
     *
     * @return string[]
     */
    abstract protected function getNonCatchablePatterns();

    /**
     * Retrieve token type. Also processes the token value if necessary.
     *
     * @param string $value
     *
     * @return T|null
     *
     * @param-out V $value
     */
    abstract protected function getType(&$value);
}

• [F] AbstractLexer.php
  Delete
• [F] Token.php
  Delete

About Section

About NFC Pay: Our Story and Mission

NFC Pay was founded with a vision to transform the way people handle transactions. Our journey is defined by a commitment to innovation, security, and convenience. We strive to deliver seamless, user-friendly payment solutions that make everyday transactions effortless and secure. Our mission is to empower you to pay with ease and confidence, anytime, anywhere.

• Simplifying Payments, One Tap at a Time.
• Reinventing Your Wallet for Modern Convenience.
• Smart Payments for a Effortless Lifestyle.
• Experience the Ease of Tap and Pay.
• Innovative Solutions for Your Daily Transactions.

FAQ Section

Frequently Asked Questions About NFC Pay

Here are answers to some common questions about NFC Pay. We aim to provide clear and concise information to help you understand how our platform works and how it can benefit you. If you have any further inquiries, please don’t hesitate to contact our support team.

How do I register for NFC Pay?

Download the app and sign up using your email or phone number, then complete the verification process.

Is my payment information secure?

Yes, we use advanced encryption and security protocols to protect your payment details.

Can I add multiple cards to my NFC Pay wallet?

Absolutely, you can link multiple debit or credit cards to your wallet.

How do I transfer money to another user?

Go to the transfer section, select the recipient, enter the amount, and authorize the transfer.

What should I do if I forget my PIN?

Use the “Forgot PIN” feature in the app to reset it following the provided instructions.

How can I activate my merchant account?

Sign up for a merchant account through the app and follow the setup instructions to start accepting payments.

Can I track my payment status?

Yes, you can view and track your payment status in the account dashboard