Proven Expertise
Our team brings years of experience in the digital payments industry to provide reliable services.
<?php
/*
* This file is part of composer/semver.
*
* (c) Composer <https://github.com/composer>
*
* For the full copyright and license information, please view
* the LICENSE file that was distributed with this source code.
*/
namespace Composer\Semver;
use Composer\Semver\Constraint\Constraint;
use Composer\Semver\Constraint\ConstraintInterface;
use Composer\Semver\Constraint\MatchAllConstraint;
use Composer\Semver\Constraint\MatchNoneConstraint;
use Composer\Semver\Constraint\MultiConstraint;
/**
* Helper class generating intervals from constraints
*
* This contains utilities for:
*
* - compacting an existing constraint which can be used to combine several into one
* by creating a MultiConstraint out of the many constraints you have.
*
* - checking whether one subset is a subset of another.
*
* Note: You should call clear to free memoization memory usage when you are done using this class
*/
class Intervals
{
/**
* @phpstan-var array<string, array{'numeric': Interval[], 'branches': array{'names': string[], 'exclude': bool}}>
*/
private static $intervalsCache = array();
/**
* @phpstan-var array<string, int>
*/
private static $opSortOrder = array(
'>=' => -3,
'<' => -2,
'>' => 2,
'<=' => 3,
);
/**
* Clears the memoization cache once you are done
*
* @return void
*/
public static function clear()
{
self::$intervalsCache = array();
}
/**
* Checks whether $candidate is a subset of $constraint
*
* @return bool
*/
public static function isSubsetOf(ConstraintInterface $candidate, ConstraintInterface $constraint)
{
if ($constraint instanceof MatchAllConstraint) {
return true;
}
if ($candidate instanceof MatchNoneConstraint || $constraint instanceof MatchNoneConstraint) {
return false;
}
$intersectionIntervals = self::get(new MultiConstraint(array($candidate, $constraint), true));
$candidateIntervals = self::get($candidate);
if (\count($intersectionIntervals['numeric']) !== \count($candidateIntervals['numeric'])) {
return false;
}
foreach ($intersectionIntervals['numeric'] as $index => $interval) {
if (!isset($candidateIntervals['numeric'][$index])) {
return false;
}
if ((string) $candidateIntervals['numeric'][$index]->getStart() !== (string) $interval->getStart()) {
return false;
}
if ((string) $candidateIntervals['numeric'][$index]->getEnd() !== (string) $interval->getEnd()) {
return false;
}
}
if ($intersectionIntervals['branches']['exclude'] !== $candidateIntervals['branches']['exclude']) {
return false;
}
if (\count($intersectionIntervals['branches']['names']) !== \count($candidateIntervals['branches']['names'])) {
return false;
}
foreach ($intersectionIntervals['branches']['names'] as $index => $name) {
if ($name !== $candidateIntervals['branches']['names'][$index]) {
return false;
}
}
return true;
}
/**
* Checks whether $a and $b have any intersection, equivalent to $a->matches($b)
*
* @return bool
*/
public static function haveIntersections(ConstraintInterface $a, ConstraintInterface $b)
{
if ($a instanceof MatchAllConstraint || $b instanceof MatchAllConstraint) {
return true;
}
if ($a instanceof MatchNoneConstraint || $b instanceof MatchNoneConstraint) {
return false;
}
$intersectionIntervals = self::generateIntervals(new MultiConstraint(array($a, $b), true), true);
return \count($intersectionIntervals['numeric']) > 0 || $intersectionIntervals['branches']['exclude'] || \count($intersectionIntervals['branches']['names']) > 0;
}
/**
* Attempts to optimize a MultiConstraint
*
* When merging MultiConstraints together they can get very large, this will
* compact it by looking at the real intervals covered by all the constraints
* and then creates a new constraint containing only the smallest amount of rules
* to match the same intervals.
*
* @return ConstraintInterface
*/
public static function compactConstraint(ConstraintInterface $constraint)
{
if (!$constraint instanceof MultiConstraint) {
return $constraint;
}
$intervals = self::generateIntervals($constraint);
$constraints = array();
$hasNumericMatchAll = false;
if (\count($intervals['numeric']) === 1 && (string) $intervals['numeric'][0]->getStart() === (string) Interval::fromZero() && (string) $intervals['numeric'][0]->getEnd() === (string) Interval::untilPositiveInfinity()) {
$constraints[] = $intervals['numeric'][0]->getStart();
$hasNumericMatchAll = true;
} else {
$unEqualConstraints = array();
for ($i = 0, $count = \count($intervals['numeric']); $i < $count; $i++) {
$interval = $intervals['numeric'][$i];
// if current interval ends with < N and next interval begins with > N we can swap this out for != N
// but this needs to happen as a conjunctive expression together with the start of the current interval
// and end of next interval, so [>=M, <N] || [>N, <P] => [>=M, !=N, <P] but M/P can be skipped if
// they are zero/+inf
if ($interval->getEnd()->getOperator() === '<' && $i+1 < $count) {
$nextInterval = $intervals['numeric'][$i+1];
if ($interval->getEnd()->getVersion() === $nextInterval->getStart()->getVersion() && $nextInterval->getStart()->getOperator() === '>') {
// only add a start if we didn't already do so, can be skipped if we're looking at second
// interval in [>=M, <N] || [>N, <P] || [>P, <Q] where unEqualConstraints currently contains
// [>=M, !=N] already and we only want to add !=P right now
if (\count($unEqualConstraints) === 0 && (string) $interval->getStart() !== (string) Interval::fromZero()) {
$unEqualConstraints[] = $interval->getStart();
}
$unEqualConstraints[] = new Constraint('!=', $interval->getEnd()->getVersion());
continue;
}
}
if (\count($unEqualConstraints) > 0) {
// this is where the end of the following interval of a != constraint is added as explained above
if ((string) $interval->getEnd() !== (string) Interval::untilPositiveInfinity()) {
$unEqualConstraints[] = $interval->getEnd();
}
// count is 1 if entire constraint is just one != expression
if (\count($unEqualConstraints) > 1) {
$constraints[] = new MultiConstraint($unEqualConstraints, true);
} else {
$constraints[] = $unEqualConstraints[0];
}
$unEqualConstraints = array();
continue;
}
// convert back >= x - <= x intervals to == x
if ($interval->getStart()->getVersion() === $interval->getEnd()->getVersion() && $interval->getStart()->getOperator() === '>=' && $interval->getEnd()->getOperator() === '<=') {
$constraints[] = new Constraint('==', $interval->getStart()->getVersion());
continue;
}
if ((string) $interval->getStart() === (string) Interval::fromZero()) {
$constraints[] = $interval->getEnd();
} elseif ((string) $interval->getEnd() === (string) Interval::untilPositiveInfinity()) {
$constraints[] = $interval->getStart();
} else {
$constraints[] = new MultiConstraint(array($interval->getStart(), $interval->getEnd()), true);
}
}
}
$devConstraints = array();
if (0 === \count($intervals['branches']['names'])) {
if ($intervals['branches']['exclude']) {
if ($hasNumericMatchAll) {
return new MatchAllConstraint;
}
// otherwise constraint should contain a != operator and already cover this
}
} else {
foreach ($intervals['branches']['names'] as $branchName) {
if ($intervals['branches']['exclude']) {
$devConstraints[] = new Constraint('!=', $branchName);
} else {
$devConstraints[] = new Constraint('==', $branchName);
}
}
// excluded branches, e.g. != dev-foo are conjunctive with the interval, so
// > 2.0 != dev-foo must return a conjunctive constraint
if ($intervals['branches']['exclude']) {
if (\count($constraints) > 1) {
return new MultiConstraint(array_merge(
array(new MultiConstraint($constraints, false)),
$devConstraints
), true);
}
if (\count($constraints) === 1 && (string)$constraints[0] === (string)Interval::fromZero()) {
if (\count($devConstraints) > 1) {
return new MultiConstraint($devConstraints, true);
}
return $devConstraints[0];
}
return new MultiConstraint(array_merge($constraints, $devConstraints), true);
}
// otherwise devConstraints contains a list of == operators for branches which are disjunctive with the
// rest of the constraint
$constraints = array_merge($constraints, $devConstraints);
}
if (\count($constraints) > 1) {
return new MultiConstraint($constraints, false);
}
if (\count($constraints) === 1) {
return $constraints[0];
}
return new MatchNoneConstraint;
}
/**
* Creates an array of numeric intervals and branch constraints representing a given constraint
*
* if the returned numeric array is empty it means the constraint matches nothing in the numeric range (0 - +inf)
* if the returned branches array is empty it means no dev-* versions are matched
* if a constraint matches all possible dev-* versions, branches will contain Interval::anyDev()
*
* @return array
* @phpstan-return array{'numeric': Interval[], 'branches': array{'names': string[], 'exclude': bool}}
*/
public static function get(ConstraintInterface $constraint)
{
$key = (string) $constraint;
if (!isset(self::$intervalsCache[$key])) {
self::$intervalsCache[$key] = self::generateIntervals($constraint);
}
return self::$intervalsCache[$key];
}
/**
* @param bool $stopOnFirstValidInterval
*
* @phpstan-return array{'numeric': Interval[], 'branches': array{'names': string[], 'exclude': bool}}
*/
private static function generateIntervals(ConstraintInterface $constraint, $stopOnFirstValidInterval = false)
{
if ($constraint instanceof MatchAllConstraint) {
return array('numeric' => array(new Interval(Interval::fromZero(), Interval::untilPositiveInfinity())), 'branches' => Interval::anyDev());
}
if ($constraint instanceof MatchNoneConstraint) {
return array('numeric' => array(), 'branches' => array('names' => array(), 'exclude' => false));
}
if ($constraint instanceof Constraint) {
return self::generateSingleConstraintIntervals($constraint);
}
if (!$constraint instanceof MultiConstraint) {
throw new \UnexpectedValueException('The constraint passed in should be an MatchAllConstraint, Constraint or MultiConstraint instance, got '.\get_class($constraint).'.');
}
$constraints = $constraint->getConstraints();
$numericGroups = array();
$constraintBranches = array();
foreach ($constraints as $c) {
$res = self::get($c);
$numericGroups[] = $res['numeric'];
$constraintBranches[] = $res['branches'];
}
if ($constraint->isDisjunctive()) {
$branches = Interval::noDev();
foreach ($constraintBranches as $b) {
if ($b['exclude']) {
if ($branches['exclude']) {
// disjunctive constraint, so only exclude what's excluded in all constraints
// !=a,!=b || !=b,!=c => !=b
$branches['names'] = array_intersect($branches['names'], $b['names']);
} else {
// disjunctive constraint so exclude all names which are not explicitly included in the alternative
// (==b || ==c) || !=a,!=b => !=a
$branches['exclude'] = true;
$branches['names'] = array_diff($b['names'], $branches['names']);
}
} else {
if ($branches['exclude']) {
// disjunctive constraint so exclude all names which are not explicitly included in the alternative
// !=a,!=b || (==b || ==c) => !=a
$branches['names'] = array_diff($branches['names'], $b['names']);
} else {
// disjunctive constraint, so just add all the other branches
// (==a || ==b) || ==c => ==a || ==b || ==c
$branches['names'] = array_merge($branches['names'], $b['names']);
}
}
}
} else {
$branches = Interval::anyDev();
foreach ($constraintBranches as $b) {
if ($b['exclude']) {
if ($branches['exclude']) {
// conjunctive, so just add all branch names to be excluded
// !=a && !=b => !=a,!=b
$branches['names'] = array_merge($branches['names'], $b['names']);
} else {
// conjunctive, so only keep included names which are not excluded
// (==a||==c) && !=a,!=b => ==c
$branches['names'] = array_diff($branches['names'], $b['names']);
}
} else {
if ($branches['exclude']) {
// conjunctive, so only keep included names which are not excluded
// !=a,!=b && (==a||==c) => ==c
$branches['names'] = array_diff($b['names'], $branches['names']);
$branches['exclude'] = false;
} else {
// conjunctive, so only keep names that are included in both
// (==a||==b) && (==a||==c) => ==a
$branches['names'] = array_intersect($branches['names'], $b['names']);
}
}
}
}
$branches['names'] = array_unique($branches['names']);
if (\count($numericGroups) === 1) {
return array('numeric' => $numericGroups[0], 'branches' => $branches);
}
$borders = array();
foreach ($numericGroups as $group) {
foreach ($group as $interval) {
$borders[] = array('version' => $interval->getStart()->getVersion(), 'operator' => $interval->getStart()->getOperator(), 'side' => 'start');
$borders[] = array('version' => $interval->getEnd()->getVersion(), 'operator' => $interval->getEnd()->getOperator(), 'side' => 'end');
}
}
$opSortOrder = self::$opSortOrder;
usort($borders, function ($a, $b) use ($opSortOrder) {
$order = version_compare($a['version'], $b['version']);
if ($order === 0) {
return $opSortOrder[$a['operator']] - $opSortOrder[$b['operator']];
}
return $order;
});
$activeIntervals = 0;
$intervals = array();
$index = 0;
$activationThreshold = $constraint->isConjunctive() ? \count($numericGroups) : 1;
$start = null;
foreach ($borders as $border) {
if ($border['side'] === 'start') {
$activeIntervals++;
} else {
$activeIntervals--;
}
if (!$start && $activeIntervals >= $activationThreshold) {
$start = new Constraint($border['operator'], $border['version']);
} elseif ($start && $activeIntervals < $activationThreshold) {
// filter out invalid intervals like > x - <= x, or >= x - < x
if (
version_compare($start->getVersion(), $border['version'], '=')
&& (
($start->getOperator() === '>' && $border['operator'] === '<=')
|| ($start->getOperator() === '>=' && $border['operator'] === '<')
)
) {
unset($intervals[$index]);
} else {
$intervals[$index] = new Interval($start, new Constraint($border['operator'], $border['version']));
$index++;
if ($stopOnFirstValidInterval) {
break;
}
}
$start = null;
}
}
return array('numeric' => $intervals, 'branches' => $branches);
}
/**
* @phpstan-return array{'numeric': Interval[], 'branches': array{'names': string[], 'exclude': bool}}
*/
private static function generateSingleConstraintIntervals(Constraint $constraint)
{
$op = $constraint->getOperator();
// handle branch constraints first
if (strpos($constraint->getVersion(), 'dev-') === 0) {
$intervals = array();
$branches = array('names' => array(), 'exclude' => false);
// != dev-foo means any numeric version may match, we treat >/< like != they are not really defined for branches
if ($op === '!=') {
$intervals[] = new Interval(Interval::fromZero(), Interval::untilPositiveInfinity());
$branches = array('names' => array($constraint->getVersion()), 'exclude' => true);
} elseif ($op === '==') {
$branches['names'][] = $constraint->getVersion();
}
return array(
'numeric' => $intervals,
'branches' => $branches,
);
}
if ($op[0] === '>') { // > & >=
return array('numeric' => array(new Interval($constraint, Interval::untilPositiveInfinity())), 'branches' => Interval::noDev());
}
if ($op[0] === '<') { // < & <=
return array('numeric' => array(new Interval(Interval::fromZero(), $constraint)), 'branches' => Interval::noDev());
}
if ($op === '!=') {
// convert !=x to intervals of 0 - <x && >x - +inf + dev*
return array('numeric' => array(
new Interval(Interval::fromZero(), new Constraint('<', $constraint->getVersion())),
new Interval(new Constraint('>', $constraint->getVersion()), Interval::untilPositiveInfinity()),
), 'branches' => Interval::anyDev());
}
// convert ==x to an interval of >=x - <=x
return array('numeric' => array(
new Interval(new Constraint('>=', $constraint->getVersion()), new Constraint('<=', $constraint->getVersion())),
), 'branches' => Interval::noDev());
}
}
How it Works
Getting started with NFC Pay is simple and quick. Register your account, add your cards, and you're ready to make payments in no time. Whether you're paying at a store, sending money to a friend, or managing your merchant transactions, NFC Pay makes it easy and secure.
Download the NFC Pay app and sign up with your email or phone number. Complete the registration process by verifying your identity, and set up your secure PIN to protect your account.
Link your debit or credit cards to your NFC Pay wallet. Simply scan your card or enter the details manually, and you’re set to load funds, shop, and pay with ease.
To pay, simply tap your phone or scan the QR code at checkout. You can also transfer money to other users with a few taps. Enjoy fast, contactless payments with top-notch security.
Security System
NFC Pay prioritizes your security with advanced features that safeguard every transaction. From SMS or email verification to end-to-end encryption, we've implemented robust measures to ensure your data is always protected. Our security systems are designed to prevent unauthorized access and provide you with a safe and reliable payment experience.
Receive instant alerts for every transaction to keep track of your account activities.
Verify your identity through our Know Your Customer process to prevent fraud and enhance security.
Dramatically supply transparent backward deliverables before caward comp internal or "organic" sources.
All your data and transactions are encrypted, ensuring that your sensitive information remains private.
Monitor unusual activity patterns to detect and prevent suspicious behavior in real-time.
Why Choice Us
With NFC Pay, you get a trusted platform backed by proven expertise and a commitment to quality. We put our customers first, offering innovative solutions tailored to your needs, ensuring every transaction is secure, swift, and seamless.
Our team brings years of experience in the digital payments industry to provide reliable services.
We prioritize excellence, ensuring that every aspect of our platform meets the highest standards.
Your needs drive our solutions, and we are dedicated to delivering a superior user experience.
We continuously evolve, integrating the latest technologies to enhance your payment experience.
Testimonial Section
Hear from our users who trust NFC Pay for their everyday transactions. Our commitment to security, ease of use, and exceptional service shines through in their experiences. See why our clients choose NFC Pay for their payment needs and how it has transformed the way they manage their finances.
App Section
Unlock the full potential of NFC Pay by downloading our app, designed to bring secure, swift, and smart transactions to your fingertips. Whether you're paying at a store, transferring money to friends, or managing your business payments, the NFC Pay app makes it effortless. Available on both iOS and Android, it's your all-in-one solution for convenient and reliable digital payments. Download now and experience the future of payments!