Assertion.php

<?php
/**
 * Assert
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to kontakt@beberlei.de so I can send you a copy immediately.
 */

namespace Assert;

use BadMethodCallException;

/**
 * Assert library
 *
 * @author Benjamin Eberlei <kontakt@beberlei.de>
 *
 * METHODSTART
 * @method static void nullOrEq($value, $value2, $message = null, $propertyPath = null)
 * @method static void nullOrSame($value, $value2, $message = null, $propertyPath = null)
 * @method static void nullOrNotEq($value1, $value2, $message = null, $propertyPath = null)
 * @method static void nullOrNotSame($value1, $value2, $message = null, $propertyPath = null)
 * @method static void nullOrInteger($value, $message = null, $propertyPath = null)
 * @method static void nullOrFloat($value, $message = null, $propertyPath = null)
 * @method static void nullOrDigit($value, $message = null, $propertyPath = null)
 * @method static void nullOrDate($value, $message = null, $propertyPath = null)
 * @method static void nullOrIntegerish($value, $message = null, $propertyPath = null)
 * @method static void nullOrBoolean($value, $message = null, $propertyPath = null)
 * @method static void nullOrScalar($value, $message = null, $propertyPath = null)
 * @method static void nullOrNotEmpty($value, $message = null, $propertyPath = null)
 * @method static void nullOrNoContent($value, $message = null, $propertyPath = null)
 * @method static void nullOrNotNull($value, $message = null, $propertyPath = null)
 * @method static void nullOrString($value, $message = null, $propertyPath = null)
 * @method static void nullOrRegex($value, $pattern, $message = null, $propertyPath = null)
 * @method static void nullOrLength($value, $length, $message = null, $propertyPath = null, $encoding = "utf8")
 * @method static void nullOrMinLength($value, $minLength, $message = null, $propertyPath = null, $encoding = "utf8")
 * @method static void nullOrMaxLength($value, $maxLength, $message = null, $propertyPath = null, $encoding = "utf8")
 * @method static void nullOrBetweenLength($value, $minLength, $maxLength, $message = null, $propertyPath = null, $encoding = "utf8")
 * @method static void nullOrStartsWith($string, $needle, $message = null, $propertyPath = null, $encoding = "utf8")
 * @method static void nullOrEndsWith($string, $needle, $message = null, $propertyPath = null, $encoding = "utf8")
 * @method static void nullOrContains($string, $needle, $message = null, $propertyPath = null, $encoding = "utf8")
 * @method static void nullOrChoice($value, $choices, $message = null, $propertyPath = null)
 * @method static void nullOrInArray($value, $choices, $message = null, $propertyPath = null)
 * @method static void nullOrNumeric($value, $message = null, $propertyPath = null)
 * @method static void nullOrIsArray($value, $message = null, $propertyPath = null)
 * @method static void nullOrIsTraversable($value, $message = null, $propertyPath = null)
 * @method static void nullOrIsArrayAccessible($value, $message = null, $propertyPath = null)
 * @method static void nullOrKeyExists($value, $key, $message = null, $propertyPath = null)
 * @method static void nullOrKeysExist($value, $keys, $message = null, $propertyPath = null)
 * @method static void nullOrKeyIsset($value, $key, $message = null, $propertyPath = null)
 * @method static void nullOrPropertyExists($value, $key, $message = null, $propertyPath = null)
 * @method static void nullOrPropertiesExist($value, $keys, $message = null, $propertyPath = null)
 * @method static void nullOrNotEmptyKey($value, $key, $message = null, $propertyPath = null)
 * @method static void nullOrNotBlank($value, $message = null, $propertyPath = null)
 * @method static void nullOrIsCallable($value, $message = null, $propertyPath = null)
 * @method static void nullOrIsInstanceOf($value, $className, $message = null, $propertyPath = null)
 * @method static void nullOrNotIsInstanceOf($value, $className, $message = null, $propertyPath = null)
 * @method static void nullOrSubclassOf($value, $className, $message = null, $propertyPath = null)
 * @method static void nullOrRange($value, $minValue, $maxValue, $message = null, $propertyPath = null)
 * @method static void nullOrMin($value, $minValue, $message = null, $propertyPath = null)
 * @method static void nullOrMax($value, $maxValue, $message = null, $propertyPath = null)
 * @method static void nullOrFile($value, $message = null, $propertyPath = null)
 * @method static void nullOrDirectory($value, $message = null, $propertyPath = null)
 * @method static void nullOrReadable($value, $message = null, $propertyPath = null)
 * @method static void nullOrWriteable($value, $message = null, $propertyPath = null)
 * @method static void nullOrEmail($value, $message = null, $propertyPath = null)
 * @method static void nullOrUrl($value, $message = null, $propertyPath = null)
 * @method static void nullOrAlnum($value, $message = null, $propertyPath = null)
 * @method static void nullOrTrue($value, $message = null, $propertyPath = null)
 * @method static void nullOrFalse($value, $message = null, $propertyPath = null)
 * @method static void nullOrClassExists($value, $message = null, $propertyPath = null)
 * @method static void nullOrImplementsInterface($class, $interfaceName, $message = null, $propertyPath = null)
 * @method static void nullOrIsJsonString($value, $message = null, $propertyPath = null)
 * @method static void nullOrUuid($value, $message = null, $propertyPath = null)
 * @method static void nullOrCount($countable, $count, $message = null, $propertyPath = null)
 * @method static void nullOrChoicesNotEmpty($values, $choices, $message = null, $propertyPath = null)
 * @method static void nullOrMethodExists($value, $object, $message = null, $propertyPath = null)
 * @method static void nullOrIsObject($value, $message = null, $propertyPath = null)
 * @method static void nullOrUtf8($value, $message = null, $propertyPath = null)
 * @method static void allEq($value, $value2, $message = null, $propertyPath = null)
 * @method static void allSame($value, $value2, $message = null, $propertyPath = null)
 * @method static void allNotEq($value1, $value2, $message = null, $propertyPath = null)
 * @method static void allNotSame($value1, $value2, $message = null, $propertyPath = null)
 * @method static void allInteger($value, $message = null, $propertyPath = null)
 * @method static void allFloat($value, $message = null, $propertyPath = null)
 * @method static void allDigit($value, $message = null, $propertyPath = null)
 * @method static void allDate($value, $message = null, $propertyPath = null)
 * @method static void allIntegerish($value, $message = null, $propertyPath = null)
 * @method static void allBoolean($value, $message = null, $propertyPath = null)
 * @method static void allScalar($value, $message = null, $propertyPath = null)
 * @method static void allNotEmpty($value, $message = null, $propertyPath = null)
 * @method static void allNoContent($value, $message = null, $propertyPath = null)
 * @method static void allNotNull($value, $message = null, $propertyPath = null)
 * @method static void allString($value, $message = null, $propertyPath = null)
 * @method static void allRegex($value, $pattern, $message = null, $propertyPath = null)
 * @method static void allLength($value, $length, $message = null, $propertyPath = null, $encoding = "utf8")
 * @method static void allMinLength($value, $minLength, $message = null, $propertyPath = null, $encoding = "utf8")
 * @method static void allMaxLength($value, $maxLength, $message = null, $propertyPath = null, $encoding = "utf8")
 * @method static void allBetweenLength($value, $minLength, $maxLength, $message = null, $propertyPath = null, $encoding = "utf8")
 * @method static void allStartsWith($string, $needle, $message = null, $propertyPath = null, $encoding = "utf8")
 * @method static void allEndsWith($string, $needle, $message = null, $propertyPath = null, $encoding = "utf8")
 * @method static void allContains($string, $needle, $message = null, $propertyPath = null, $encoding = "utf8")
 * @method static void allChoice($value, $choices, $message = null, $propertyPath = null)
 * @method static void allInArray($value, $choices, $message = null, $propertyPath = null)
 * @method static void allNumeric($value, $message = null, $propertyPath = null)
 * @method static void allIsArray($value, $message = null, $propertyPath = null)
 * @method static void allIsTraversable($value, $message = null, $propertyPath = null)
 * @method static void allIsArrayAccessible($value, $message = null, $propertyPath = null)
 * @method static void allKeyExists($value, $key, $message = null, $propertyPath = null)
 * @method static void allKeysExist($value, $keys, $message = null, $propertyPath = null)
 * @method static void allKeyIsset($value, $key, $message = null, $propertyPath = null)
 * @method static void allPropertyExists($value, $key, $message = null, $propertyPath = null)
 * @method static void allPropertiesExist($value, $keys, $message = null, $propertyPath = null)
 * @method static void allNotEmptyKey($value, $key, $message = null, $propertyPath = null)
 * @method static void allNotBlank($value, $message = null, $propertyPath = null)
 * @method static void allIsCallable($value, $message = null, $propertyPath = null)
 * @method static void allIsInstanceOf($value, $className, $message = null, $propertyPath = null)
 * @method static void allNotIsInstanceOf($value, $className, $message = null, $propertyPath = null)
 * @method static void allSubclassOf($value, $className, $message = null, $propertyPath = null)
 * @method static void allRange($value, $minValue, $maxValue, $message = null, $propertyPath = null)
 * @method static void allMin($value, $minValue, $message = null, $propertyPath = null)
 * @method static void allMax($value, $maxValue, $message = null, $propertyPath = null)
 * @method static void allFile($value, $message = null, $propertyPath = null)
 * @method static void allDirectory($value, $message = null, $propertyPath = null)
 * @method static void allReadable($value, $message = null, $propertyPath = null)
 * @method static void allWriteable($value, $message = null, $propertyPath = null)
 * @method static void allEmail($value, $message = null, $propertyPath = null)
 * @method static void allUrl($value, $message = null, $propertyPath = null)
 * @method static void allAlnum($value, $message = null, $propertyPath = null)
 * @method static void allTrue($value, $message = null, $propertyPath = null)
 * @method static void allFalse($value, $message = null, $propertyPath = null)
 * @method static void allClassExists($value, $message = null, $propertyPath = null)
 * @method static void allImplementsInterface($class, $interfaceName, $message = null, $propertyPath = null)
 * @method static void allIsJsonString($value, $message = null, $propertyPath = null)
 * @method static void allUuid($value, $message = null, $propertyPath = null)
 * @method static void allCount($countable, $count, $message = null, $propertyPath = null)
 * @method static void allChoicesNotEmpty($values, $choices, $message = null, $propertyPath = null)
 * @method static void allMethodExists($value, $object, $message = null, $propertyPath = null)
 * @method static void allIsObject($value, $message = null, $propertyPath = null)
 * @method static void allUtf8($value, $message = null, $propertyPath = null)
 * METHODEND
 */
class Assertion
{
    const INVALID_FLOAT             = 9;
    const INVALID_INTEGER           = 10;
    const INVALID_DIGIT             = 11;
    const INVALID_INTEGERISH        = 12;
    const INVALID_BOOLEAN           = 13;
    const VALUE_EMPTY               = 14;
    const VALUE_NULL                = 15;
    const INVALID_STRING            = 16;
    const INVALID_REGEX             = 17;
    const INVALID_MIN_LENGTH        = 18;
    const INVALID_MAX_LENGTH        = 19;
    const INVALID_STRING_START      = 20;
    const INVALID_STRING_CONTAINS   = 21;
    const INVALID_CHOICE            = 22;
    const INVALID_NUMERIC           = 23;
    const INVALID_ARRAY             = 24;
    const INVALID_KEY_EXISTS        = 26;
    const INVALID_NOT_BLANK         = 27;
    const INVALID_INSTANCE_OF       = 28;
    const INVALID_SUBCLASS_OF       = 29;
    const INVALID_RANGE             = 30;
    const INVALID_ALNUM             = 31;
    const INVALID_TRUE              = 32;
    const INVALID_EQ                = 33;
    const INVALID_SAME              = 34;
    const INVALID_MIN               = 35;
    const INVALID_MAX               = 36;
    const INVALID_LENGTH            = 37;
    const INVALID_FALSE             = 38;
    const INVALID_STRING_END        = 39;
    const INVALID_UUID              = 40;
    const INVALID_COUNT             = 41;
    const INVALID_NOT_EQ            = 42;
    const INVALID_NOT_SAME          = 43;
    const INVALID_TRAVERSABLE       = 44;
    const INVALID_ARRAY_ACCESSIBLE  = 45;
    const INVALID_KEY_ISSET         = 46;
    const INVALID_DIRECTORY         = 101;
    const INVALID_FILE              = 102;
    const INVALID_READABLE          = 103;
    const INVALID_WRITEABLE         = 104;
    const INVALID_CLASS             = 105;
    const INVALID_EMAIL             = 201;
    const INTERFACE_NOT_IMPLEMENTED = 202;
    const INVALID_URL               = 203;
    const INVALID_NOT_INSTANCE_OF   = 204;
    const VALUE_NOT_EMPTY           = 205;
    const INVALID_JSON_STRING       = 206;
    const INVALID_OBJECT            = 207;
    const INVALID_METHOD            = 208;
    const INVALID_SCALAR            = 209;
    const INVALID_DATE              = 210;
    const INVALID_CALLABLE          = 211;
    const INVALID_KEYS_EXIST        = 300;
    const INVALID_PROPERTY_EXISTS   = 301;
    const INVALID_PROPERTIES_EXIST  = 302;
    const INVALID_UTF8              = 303;
    /**
     * Exception to throw when an assertion failed.
     *
     * @var string
     */
    static protected $exceptionClass = 'Assert\InvalidArgumentException';

    /**
     * Helper method that handles building the assertion failure exceptions.
     * They are returned from this method so that the stack trace still shows
     * the assertions method.
     */
    protected static function createException($value, $message, $code, $propertyPath, array $constraints = array())
    {
        $exceptionClass = static::$exceptionClass;
        return new $exceptionClass($message, $code, $propertyPath, $value, $constraints);
    }

    public static function setExceptionClass($exceptionClass)
    {
        static::$exceptionClass = $exceptionClass;
    }

    /**
     * Assert that two values are equal (using == ).
     *
     * @param mixed $value
     * @param mixed $value2
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function eq($value, $value2, $message = null, $propertyPath = null)
    {
        if ($value != $value2) {
            $message = sprintf(
                $message ?: 'Value "%s" does not equal expected value "%s".',
                self::stringify($value),
                self::stringify($value2)
            );

            throw static::createException($value, $message, static::INVALID_EQ, $propertyPath, array('expected' => $value2));
        }
    }

    /**
     * Assert that two values are the same (using ===).
     *
     * @param mixed $value
     * @param mixed $value2
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function same($value, $value2, $message = null, $propertyPath = null)
    {
        if ($value !== $value2) {
            $message = sprintf(
                $message ?: 'Value "%s" is not the same as expected value "%s".',
                self::stringify($value),
                self::stringify($value2)
            );

            throw static::createException($value, $message, static::INVALID_SAME, $propertyPath, array('expected' => $value2));
        }
    }

    /**
     * Assert that two values are not equal (using == ).
     *
     * @param mixed $value1
     * @param mixed $value2
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function notEq($value1, $value2, $message = null, $propertyPath = null)
    {
        if ($value1 == $value2) {
            $message = sprintf(
                $message ?: 'Value "%s" is equal to expected value "%s".',
                self::stringify($value1),
                self::stringify($value2)
            );
            throw static::createException($value1, $message,static::INVALID_NOT_EQ, $propertyPath, array('expected' => $value2));
        }
    }

    /**
     * Assert that two values are not the same (using === ).
     *
     * @param mixed $value1
     * @param mixed $value2
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function notSame($value1, $value2, $message = null, $propertyPath = null)
    {
        if ($value1 === $value2) {
            $message = sprintf(
                $message ?: 'Value "%s" is the same as expected value "%s".',
                self::stringify($value1),
                self::stringify($value2)
            );
            throw static::createException($value1, $message, static::INVALID_NOT_SAME, $propertyPath, array('expected' => $value2));
        }
    }

    /**
     * Assert that value is a php integer.
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function integer($value, $message = null, $propertyPath = null)
    {
        if ( ! is_int($value)) {
            $message = sprintf(
                $message ?: 'Value "%s" is not an integer.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_INTEGER, $propertyPath);
        }
    }

    /**
     * Assert that value is a php float.
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function float($value, $message = null, $propertyPath = null)
    {
        if ( ! is_float($value)) {
            $message = sprintf(
                $message ?: 'Value "%s" is not a float.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_FLOAT, $propertyPath);
        }
    }

    /**
     * Validates if an integer or integerish is a digit.
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function digit($value, $message = null, $propertyPath = null)
    {
        if ( ! ctype_digit((string)$value)) {
            $message = sprintf(
                $message ?: 'Value "%s" is not a digit.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_DIGIT, $propertyPath);
        }
    }

    /**
     * Validates if an string is a date .
     *
     * @param string $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function date($value, $message=null, $propertyPath=null)
    {
        if ( strtotime($value) === false )
        {
            $message = sprintf(
                $message ?: 'Value "%s" is not a date.',
                self::stringify($value)
            );
            throw static::createException($value, $message, static::INVALID_DATE, $propertyPath);
        }
    }

    /**
     * Assert that value is a php integer'ish.
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function integerish($value, $message = null, $propertyPath = null)
    {
        if (is_object($value) || strval(intval($value)) != $value || is_bool($value) || is_null($value)) {
            $message = sprintf(
                $message ?: 'Value "%s" is not an integer or a number castable to integer.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_INTEGERISH, $propertyPath);
        }
    }

    /**
     * Assert that value is php boolean
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function boolean($value, $message = null, $propertyPath = null)
    {
        if ( ! is_bool($value)) {
            $message = sprintf(
                $message ?: 'Value "%s" is not a boolean.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_BOOLEAN, $propertyPath);
        }
    }

    /**
     * Assert that value is a PHP scalar
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function scalar($value, $message = null, $propertyPath = null)
    {
        if (!is_scalar($value)) {
            $message = sprintf(
                $message ?: 'Value "%s" is not a scalar.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_SCALAR, $propertyPath);
        }
    }

    /**
     * Assert that value is not empty
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function notEmpty($value, $message = null, $propertyPath = null)
    {
        if (empty($value)) {
            $message = sprintf(
                $message ?: 'Value "%s" is empty, but non empty value was expected.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::VALUE_EMPTY, $propertyPath);
        }
    }

    /**
     * Assert that value is empty
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function noContent($value, $message = null, $propertyPath = null)
    {
        if (!empty($value)) {
            $message = sprintf(
                $message ?: 'Value "%s" is not empty, but empty value was expected.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::VALUE_NOT_EMPTY, $propertyPath);
        }
    }

    /**
     * Assert that value is not null
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function notNull($value, $message = null, $propertyPath = null)
    {
        if ($value === null) {
            $message = sprintf(
                $message ?: 'Value "%s" is null, but non null value was expected.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::VALUE_NULL, $propertyPath);
        }
    }

    /**
     * Assert that value is a string
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function string($value, $message = null, $propertyPath = null)
    {
        if ( ! is_string($value)) {
            $message = sprintf(
                $message ?: 'Value "%s" expected to be string, type %s given.',
                self::stringify($value),
                gettype($value)
            );

            throw static::createException($value, $message, static::INVALID_STRING, $propertyPath);
        }
    }

    /**
     * Assert that value matches a regex
     *
     * @param mixed $value
     * @param string $pattern
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function regex($value, $pattern, $message = null, $propertyPath = null)
    {
        static::string($value, $message, $propertyPath);

        if ( ! preg_match($pattern, $value)) {
            $message = sprintf(
                $message ?: 'Value "%s" does not match expression.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_REGEX , $propertyPath, array('pattern' => $pattern));
        }
    }

    /**
     * Assert that string has a given length.
     *
     * @param mixed $value
     * @param int $length
     * @param string|null $message
     * @param string|null $propertyPath
     * @param string $encoding
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function length($value, $length, $message = null, $propertyPath = null, $encoding = 'utf8')
    {
        static::string($value, $message, $propertyPath);

        if (mb_strlen($value, $encoding) !== $length) {
            $message = sprintf(
                $message ?: 'Value "%s" has to be %d exactly characters long, but length is %d.',
                self::stringify($value),
                $length,
                mb_strlen($value, $encoding)
            );

            $constraints = array('length' => $length, 'encoding' => $encoding);
            throw static::createException($value, $message, static::INVALID_LENGTH, $propertyPath, $constraints);
        }
    }

    /**
     * Assert that a string is at least $minLength chars long.
     *
     * @param mixed $value
     * @param int $minLength
     * @param string|null $message
     * @param string|null $propertyPath
     * @param string $encoding
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function minLength($value, $minLength, $message = null, $propertyPath = null, $encoding = 'utf8')
    {
        static::string($value, $message, $propertyPath);

        if (mb_strlen($value, $encoding) < $minLength) {
            $message = sprintf(
                $message ?: 'Value "%s" is too short, it should have more than %d characters, but only has %d characters.',
                self::stringify($value),
                $minLength,
                mb_strlen($value, $encoding)
            );

            $constraints = array('min_length' => $minLength, 'encoding' => $encoding);
            throw static::createException($value, $message, static::INVALID_MIN_LENGTH, $propertyPath, $constraints);
        }
    }

    /**
     * Assert that string value is not longer than $maxLength chars.
     *
     * @param mixed $value
     * @param integer $maxLength
     * @param string|null $message
     * @param string|null $propertyPath
     * @param string $encoding
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function maxLength($value, $maxLength, $message = null, $propertyPath = null, $encoding = 'utf8')
    {
        static::string($value, $message, $propertyPath);

        if (mb_strlen($value, $encoding) > $maxLength) {
            $message = sprintf(
                $message ?: 'Value "%s" is too long, it should have no more than %d characters, but has %d characters.',
                self::stringify($value),
                $maxLength,
                mb_strlen($value, $encoding)
            );

            $constraints = array('max_length' => $maxLength, 'encoding' => $encoding);
            throw static::createException($value, $message, static::INVALID_MAX_LENGTH, $propertyPath, $constraints);
        }
    }

    /**
     * Assert that string length is between min,max lengths.
     *
     * @param mixed $value
     * @param integer $minLength
     * @param integer $maxLength
     * @param string|null $message
     * @param string|null $propertyPath
     * @param string $encoding
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function betweenLength($value, $minLength, $maxLength, $message = null, $propertyPath = null, $encoding = 'utf8')
    {
        static::string($value, $message, $propertyPath);

        if (mb_strlen($value, $encoding) < $minLength) {
            $message = sprintf(
                $message ?: 'Value "%s" is too short, it should have more than %d characters, but only has %d characters.',
                self::stringify($value),
                $minLength,
                mb_strlen($value, $encoding)
            );

            $constraints = array('min_length' => $minLength, 'encoding' => $encoding);
            throw static::createException($value, $message, static::INVALID_MIN_LENGTH, $propertyPath, $constraints);
        }

        if (mb_strlen($value, $encoding) > $maxLength) {
            $message = sprintf(
                $message ?: 'Value "%s" is too long, it should have no more than %d characters, but has %d characters.',
                self::stringify($value),
                $maxLength,
                mb_strlen($value, $encoding)
            );

            $constraints = array('max_length' => $maxLength, 'encoding' => $encoding);
            throw static::createException($value, $message, static::INVALID_MAX_LENGTH, $propertyPath, $constraints);
        }
    }

    /**
     * Assert that string starts with a sequence of chars.
     *
     * @param mixed $string
     * @param string $needle
     * @param string|null $message
     * @param string|null $propertyPath
     * @param string $encoding
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function startsWith($string, $needle, $message = null, $propertyPath = null, $encoding = 'utf8')
    {
        static::string($string, $message, $propertyPath);

        if (mb_strpos($string, $needle, null, $encoding) !== 0) {
            $message = sprintf(
                $message ?: 'Value "%s" does not start with "%s".',
                self::stringify($string),
                self::stringify($needle)
            );

            $constraints = array('needle' => $needle, 'encoding' => $encoding);
            throw static::createException($string, $message, static::INVALID_STRING_START, $propertyPath, $constraints);
        }
    }

    /**
     * Assert that string ends with a sequence of chars.
     *
     * @param mixed $string
     * @param string $needle
     * @param string|null $message
     * @param string|null $propertyPath
     * @param string $encoding
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function endsWith($string, $needle, $message = null, $propertyPath = null, $encoding = 'utf8')
    {
        static::string($string, $message, $propertyPath);

        $stringPosition = mb_strlen($string, $encoding) - mb_strlen($needle, $encoding);

        if (mb_strripos($string, $needle, null, $encoding) !== $stringPosition) {
            $message = sprintf(
                $message ?: 'Value "%s" does not end with "%s".',
                self::stringify($string),
                self::stringify($needle)
            );

            $constraints = array('needle' => $needle, 'encoding' => $encoding);
            throw static::createException($string, $message, static::INVALID_STRING_END, $propertyPath, $constraints);
        }
    }

    /**
     * Assert that string contains a sequence of chars.
     *
     * @param mixed $string
     * @param string $needle
     * @param string|null $message
     * @param string|null $propertyPath
     * @param string $encoding
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function contains($string, $needle, $message = null, $propertyPath = null, $encoding = 'utf8')
    {
        static::string($string, $message, $propertyPath);

        if (mb_strpos($string, $needle, null, $encoding) === false) {
            $message = sprintf(
                $message ?: 'Value "%s" does not contain "%s".',
                self::stringify($string),
                self::stringify($needle)
            );

            $constraints = array('needle' => $needle, 'encoding' => $encoding);
            throw static::createException($string, $message, static::INVALID_STRING_CONTAINS, $propertyPath, $constraints);
        }
    }

    /**
     * Assert that value is in array of choices.
     *
     * @param mixed $value
     * @param array $choices
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function choice($value, array $choices, $message = null, $propertyPath = null)
    {
        if ( ! in_array($value, $choices, true)) {
            $message = sprintf(
                $message ?: 'Value "%s" is not an element of the valid values: %s',
                self::stringify($value),
                implode(", ", array_map('Assert\Assertion::stringify', $choices))
            );

            throw static::createException($value, $message, static::INVALID_CHOICE, $propertyPath, array('choices' => $choices));
        }
    }

    /**
     * Alias of {@see choice()}
     *
     * @throws \Assert\AssertionFailedException
     */
    public static function inArray($value, array $choices, $message = null, $propertyPath = null)
    {
        static::choice($value, $choices, $message, $propertyPath);
    }

    /**
     * Assert that value is numeric.
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function numeric($value, $message = null, $propertyPath = null)
    {
        if ( ! is_numeric($value)) {
            $message = sprintf(
                $message ?: 'Value "%s" is not numeric.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_NUMERIC, $propertyPath);
        }
    }

    /**
     * Assert that value is an array.
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function isArray($value, $message = null, $propertyPath = null)
    {
        if ( ! is_array($value)) {
            $message = sprintf(
                $message ?: 'Value "%s" is not an array.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_ARRAY, $propertyPath);
        }
    }

    /**
     * Assert that value is an array or a traversable object.
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function isTraversable($value, $message = null, $propertyPath = null)
    {
        if ( ! is_array($value) && ! $value instanceof \Traversable) {
            $message = sprintf(
                $message ?: 'Value "%s" is not an array and does not implement Traversable.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_TRAVERSABLE, $propertyPath);
        }
    }

    /**
     * Assert that value is an array or an array-accessible object.
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function isArrayAccessible($value, $message = null, $propertyPath = null)
    {
        if ( ! is_array($value) && ! $value instanceof \ArrayAccess) {
            $message = sprintf(
                $message ?: 'Value "%s" is not an array and does not implement ArrayAccess.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_ARRAY_ACCESSIBLE, $propertyPath);
        }
    }

    /**
     * Assert that key exists in an array
     *
     * @param mixed $value
     * @param string|integer $key
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function keyExists($value, $key, $message = null, $propertyPath = null)
    {
        static::isArray($value, $message, $propertyPath);

        if ( ! array_key_exists($key, $value)) {
            $message = sprintf(
                $message ?: 'Array does not contain an element with key "%s"',
                self::stringify($key)
            );

            throw static::createException($value, $message, static::INVALID_KEY_EXISTS, $propertyPath, array('key' => $key));
        }
    }

    /**
     * Assert that keys exist in array
     *
     * @param mixed $value
     * @param string|integer $key
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function keysExist($value, $keys, $message = null, $propertyPath = null)
    {
        static::isArray($value, $message, $propertyPath);

        foreach ( $keys as $key ) {

            if ( ! array_key_exists($key, $value)) {
                $message = $message ?: sprintf(
                    'Array does not contain an element with key "%s"',
                    self::stringify($key)
                );

                throw static::createException($value, $message, static::INVALID_KEYS_EXIST, $propertyPath, array('key' => $key));
            }
        }

    }

    /**
     * Assert that property exists in array
     *
     * @param mixed $value
     * @param string|integer $key
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function propertyExists($value, $key, $message = null, $propertyPath = null)
    {
        static::isObject($value);

        if ( ! property_exists($value, $key) && ! isset($value->$key) ) {
            $message = $message ?: sprintf(
                'Object does not contain an property with key "%s"',
                self::stringify($key)
            );

            throw static::createException($value, $message, static::INVALID_PROPERTY_EXISTS, $propertyPath, array('key' => $key));

        }
    }

    /**
     * Assert that properties exists in array
     *
     * @param mixed $value
     * @param array $keys
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function propertiesExist($value, array $keys, $message = null, $propertyPath = null)
    {
        static::isObject($value);
        foreach ($keys as $key )
        {
            // Using isset to allow resolution of magically defined properties
            if ( ! property_exists($value, $key) && ! isset($value->$key) )
            {
                $message = $message ?: sprintf(
                    'Object does not contain an property with key "%s"',
                    self::stringify($key)
                );
                throw static::createException($value, $message, static::INVALID_PROPERTIES_EXIST, $propertyPath, array('key' => $key));
            }
        }
    }

    /**
     * Assert that string is valid utf8
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function utf8($value, $message = null, $propertyPath = null)
    {
        static::string($value, $message, $propertyPath);

        if  ( mb_detect_encoding($value, 'UTF-8', true) !== 'UTF-8' ) {
            $message = $message ?: sprintf(
                'Value "%s" was expected to be a valid UTF8 string',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_UTF8, $propertyPath);
        }

    }

    /**
     * Assert that key exists in an array/array-accessible object using isset()
     *
     * @param mixed $value
     * @param string|integer $key
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function keyIsset($value, $key, $message = null, $propertyPath = null)
    {
        static::isArrayAccessible($value, $message, $propertyPath);

        if ( ! isset($value[$key])) {
            $message = sprintf(
                $message ?: 'The element with key "%s" was not found',
                self::stringify($key)
            );

            throw static::createException($value, $message, static::INVALID_KEY_ISSET, $propertyPath, array('key' => $key));
        }
    }

    /**
     * Assert that key exists in an array/array-accessible object and it's value is not empty.
     *
     * @param mixed $value
     * @param string|integer $key
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function notEmptyKey($value, $key, $message = null, $propertyPath = null)
    {
        static::keyIsset($value, $key, $message, $propertyPath);
        static::notEmpty($value[$key], $message, $propertyPath);
    }

    /**
     * Assert that value is not blank
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function notBlank($value, $message = null, $propertyPath = null)
    {
        if (false === $value || (empty($value) && '0' != $value)) {
            $message = sprintf(
                $message ?: 'Value "%s" is blank, but was expected to contain a value.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_NOT_BLANK, $propertyPath);
        }
    }

    /**
     * Assert that value is instance of given class-name.
     *
     * @param mixed $value
     * @param string $className
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function isInstanceOf($value, $className, $message = null, $propertyPath = null)
    {
        if ( ! ($value instanceof $className)) {
            $message = sprintf(
                $message ?: 'Class "%s" was expected to be instanceof of "%s" but is not.',
                self::stringify($value),
                $className
            );

            throw static::createException($value, $message, static::INVALID_INSTANCE_OF, $propertyPath, array('class' => $className));
        }
    }

    /**
     * Assert that value is not instance of given class-name.
     *
     * @param mixed $value
     * @param string $className
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function notIsInstanceOf($value, $className, $message = null, $propertyPath = null)
    {
        if ($value instanceof $className) {
            $message = sprintf(
                $message ?: 'Class "%s" was not expected to be instanceof of "%s".',
                self::stringify($value),
                $className
            );

            throw static::createException($value, $message, static::INVALID_NOT_INSTANCE_OF, $propertyPath, array('class' => $className));
        }
    }

    /**
     * Assert that value is subclass of given class-name.
     *
     * @param mixed $value
     * @param string $className
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function subclassOf($value, $className, $message = null, $propertyPath = null)
    {
        if ( ! is_subclass_of($value, $className)) {
            $message = sprintf(
                $message ?: 'Class "%s" was expected to be subclass of "%s".',
                self::stringify($value),
                $className
            );

            throw static::createException($value, $message, static::INVALID_SUBCLASS_OF, $propertyPath, array('class' => $className));
        }
    }

    /**
     * Assert that value is in range of numbers.
     *
     * @param mixed $value
     * @param integer $minValue
     * @param integer $maxValue
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function range($value, $minValue, $maxValue, $message = null, $propertyPath = null)
    {
        static::numeric($value, $message, $propertyPath);

        if ($value < $minValue || $value > $maxValue) {
            $message = sprintf(
                $message ?: 'Number "%s" was expected to be at least "%d" and at most "%d".',
                self::stringify($value),
                self::stringify($minValue),
                self::stringify($maxValue)
            );

            throw static::createException($value, $message, static::INVALID_RANGE, $propertyPath, array('min' => $minValue, 'max' => $maxValue));
        }
    }

    /**
     * Assert that a value is at least as big as a given limit
     *
     * @param mixed $value
     * @param mixed $minValue
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function min($value, $minValue, $message = null, $propertyPath = null)
    {
        static::numeric($value, $message, $propertyPath);

        if ($value < $minValue) {
            $message = sprintf(
                $message ?: 'Number "%s" was expected to be at least "%d".',
                self::stringify($value),
                self::stringify($minValue)
            );

            throw static::createException($value, $message, static::INVALID_MIN, $propertyPath, array('min' => $minValue));
        }
    }

    /**
     * Assert that a number is smaller as a given limit
     *
     * @param mixed $value
     * @param mixed $maxValue
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function max($value, $maxValue, $message = null, $propertyPath = null)
    {
        static::numeric($value, $message, $propertyPath);

        if ($value > $maxValue) {
            $message = sprintf(
                $message ?: 'Number "%s" was expected to be at most "%d".',
                self::stringify($value),
                self::stringify($maxValue)
            );

            throw static::createException($value, $message, static::INVALID_MAX, $propertyPath, array('max' => $maxValue));
        }
    }

    /**
     * Assert that a file exists
     *
     * @param string $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function file($value, $message = null, $propertyPath = null)
    {
        static::string($value, $message, $propertyPath);
        static::notEmpty($value, $message, $propertyPath);

        if ( ! is_file($value)) {
            $message = sprintf(
                $message ?: 'File "%s" was expected to exist.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_FILE, $propertyPath);
        }
    }

    /**
     * Assert that a directory exists
     *
     * @param string $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function directory($value, $message = null, $propertyPath = null)
    {
        static::string($value, $message, $propertyPath);

        if ( ! is_dir($value)) {
            $message = sprintf(
                $message ?: 'Path "%s" was expected to be a directory.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_DIRECTORY, $propertyPath);
        }
    }

    /**
     * Assert that the value is something readable
     *
     * @param string $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function readable($value, $message = null, $propertyPath = null)
    {
        static::string($value, $message, $propertyPath);

        if ( ! is_readable($value)) {
            $message = sprintf(
                $message ?: 'Path "%s" was expected to be readable.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_READABLE, $propertyPath);
        }
    }

    /**
     * Assert that the value is something writeable
     *
     * @param string $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function writeable($value, $message = null, $propertyPath = null)
    {
        static::string($value, $message, $propertyPath);

        if ( ! is_writeable($value)) {
            $message = sprintf(
                $message ?: 'Path "%s" was expected to be writeable.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_WRITEABLE, $propertyPath);
        }
    }

    /**
     * Assert that value is an email adress (using
     * input_filter/FILTER_VALIDATE_EMAIL).
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function email($value, $message = null, $propertyPath = null)
    {
        static::string($value, $message, $propertyPath);

        if ( ! filter_var($value, FILTER_VALIDATE_EMAIL)) {
            $message = sprintf(
                $message ?: 'Value "%s" was expected to be a valid e-mail address.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_EMAIL, $propertyPath);
        } else {
            $host = substr($value, strpos($value, '@') + 1);

            // Likely not a FQDN, bug in PHP FILTER_VALIDATE_EMAIL prior to PHP 5.3.3
            if (version_compare(PHP_VERSION, '5.3.3', '<') && strpos($host, '.') === false) {
                $message = sprintf(
                    $message ?: 'Value "%s" was expected to be a valid e-mail address.',
                    self::stringify($value)
                );

                throw static::createException($value, $message, static::INVALID_EMAIL, $propertyPath);
            }
        }
    }

    /**
     * Assert that value is an URL.
     *
     * This code snipped was taken from the Symfony project and modified to the special demands of this method.
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     *
     *
     * @link https://github.com/symfony/Validator/blob/master/Constraints/UrlValidator.php
     * @link https://github.com/symfony/Validator/blob/master/Constraints/Url.php
     */
    public static function url($value, $message = null, $propertyPath = null)
    {
        static::string($value, $message, $propertyPath);

        $protocols = array('http', 'https');

        $pattern = '~^
            (%s)://                                 # protocol
            (
                ([\pL\pN\pS-]+\.)+[\pL]+                   # a domain name
                    |                                     #  or
                \d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}      # a IP address
                    |                                     #  or
                \[
                    (?:(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){6})(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:::(?:(?:(?:[0-9a-f]{1,4})):){5})(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:[0-9a-f]{1,4})))?::(?:(?:(?:[0-9a-f]{1,4})):){4})(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,1}(?:(?:[0-9a-f]{1,4})))?::(?:(?:(?:[0-9a-f]{1,4})):){3})(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,2}(?:(?:[0-9a-f]{1,4})))?::(?:(?:(?:[0-9a-f]{1,4})):){2})(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,3}(?:(?:[0-9a-f]{1,4})))?::(?:(?:[0-9a-f]{1,4})):)(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,4}(?:(?:[0-9a-f]{1,4})))?::)(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,5}(?:(?:[0-9a-f]{1,4})))?::)(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,6}(?:(?:[0-9a-f]{1,4})))?::))))
                \]  # a IPv6 address
            )
            (:[0-9]+)?                              # a port (optional)
            (/?|/\S+)                               # a /, nothing or a / with something
        $~ixu';

        $pattern = sprintf($pattern, implode('|', $protocols));

        if (!preg_match($pattern, $value)) {
            $message = sprintf(
                $message ?: 'Value "%s" was expected to be a valid URL starting with http or https',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_URL, $propertyPath);
        }

    }

    /**
     * Assert that value is alphanumeric.
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function alnum($value, $message = null, $propertyPath = null)
    {
        try {
            static::regex($value, '(^([a-zA-Z]{1}[a-zA-Z0-9]*)$)', $message, $propertyPath);
        } catch(AssertionFailedException $e) {
            $message = sprintf(
                $message ?: 'Value "%s" is not alphanumeric, starting with letters and containing only letters and numbers.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_ALNUM, $propertyPath);
        }
    }

    /**
     * Assert that the value is boolean True.
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function true($value, $message = null, $propertyPath = null)
    {
        if ($value !== true) {
            $message = sprintf(
                $message ?: 'Value "%s" is not TRUE.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_TRUE, $propertyPath);
        }
    }

    /**
     * Assert that the value is boolean False.
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function false($value, $message = null, $propertyPath = null)
    {
        if ($value !== false) {
            $message = sprintf(
                $message ?: 'Value "%s" is not FALSE.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_FALSE, $propertyPath);
        }
    }

    /**
     * Assert that the class exists.
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function classExists($value, $message = null, $propertyPath = null)
    {
        if ( ! class_exists($value)) {
            $message = sprintf(
                $message ?: 'Class "%s" does not exist.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_CLASS, $propertyPath);
        }
    }

    /**
     * Assert that the class implements the interface
     *
     * @param mixed $class
     * @param string $interfaceName
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function implementsInterface($class, $interfaceName, $message = null, $propertyPath = null)
    {
        $reflection = new \ReflectionClass($class);
        if ( ! $reflection->implementsInterface($interfaceName)) {
            $message = sprintf(
                $message ?: 'Class "%s" does not implement interface "%s".',
                self::stringify($class),
                self::stringify($interfaceName)
            );

            throw static::createException($class, $message, static::INTERFACE_NOT_IMPLEMENTED, $propertyPath, array('interface' => $interfaceName));
        }
    }

    /**
     * Assert that the given string is a valid json string.
     *
     * NOTICE:
     * Since this does a json_decode to determine its validity
     * you probably should consider, when using the variable
     * content afterwards, just to decode and check for yourself instead
     * of using this assertion.
     *
     * @param mixed $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function isJsonString($value, $message = null, $propertyPath = null)
    {
        if (null === json_decode($value) && JSON_ERROR_NONE !== json_last_error()) {
            $message = sprintf(
                $message ?: 'Value "%s" is not a valid JSON string.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_JSON_STRING, $propertyPath);
        }
    }

    /**
     * Assert that the given string is a valid UUID
     *
     * Uses code from {@link https://github.com/ramsey/uuid} that is MIT licensed.
     *
     * @param string $value
     * @param string|null $message
     * @param string|null $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function uuid($value, $message = null, $propertyPath = null)
    {
        $value = str_replace(array('urn:', 'uuid:', '{', '}'), '', $value);

        if ($value === '00000000-0000-0000-0000-000000000000') {
            return;
        }

        if (!preg_match('/^[0-9A-Fa-f]{8}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{12}$/', $value)) {
            $message = sprintf(
                $message ?: 'Value "%s" is not a valid UUID.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_UUID, $propertyPath);
        }
    }

    /**
     * Assert that the count of countable is equal to count.
     *
     * @param array|\Countable $countable
     * @param int              $count
     * @param string           $message
     * @param string           $propertyPath
     * @return void
     * @throws \Assert\AssertionFailedException
     */
    public static function count($countable, $count, $message = null, $propertyPath = null)
    {
        if ($count !== count($countable)) {
            $message = sprintf(
                $message ?: 'List does not contain exactly "%d" elements.',
                self::stringify($countable),
                self::stringify($count)
            );

            throw static::createException($countable, $message, static::INVALID_COUNT, $propertyPath, array('count' => $count));
        }
    }

    /**
     * static call handler to implement:
     *  - "null or assertion" delegation
     *  - "all" delegation
     */
    public static function __callStatic($method, $args)
    {
        if (strpos($method, "nullOr") === 0) {
            if ( ! array_key_exists(0, $args)) {
                throw new BadMethodCallException("Missing the first argument.");
            }

            if ($args[0] === null) {
                return;
            }

            $method = substr($method, 6);

            return call_user_func_array(array(get_called_class(), $method), $args);
        }

        if (strpos($method, "all") === 0) {
            if ( ! array_key_exists(0, $args)) {
                throw new BadMethodCallException("Missing the first argument.");
            }

            static::isTraversable($args[0]);

            $method      = substr($method, 3);
            $values      = array_shift($args);
            $calledClass = get_called_class();

            foreach ($values as $value) {
                call_user_func_array(array($calledClass, $method), array_merge(array($value), $args));
            }

            return;
        }

        throw new BadMethodCallException("No assertion Assertion#" . $method . " exists.");
    }

    /**
     * Determines if the values array has every choice as key and that this choice has content.
     *
     * @param array $values
     * @param array $choices
     * @param null  $message
     * @param null  $propertyPath
     */
    public static function choicesNotEmpty(array $values, array $choices, $message = null, $propertyPath = null)
    {
        self::notEmpty($values, $message, $propertyPath);

        foreach ($choices as $choice) {

            self::notEmptyKey($values, $choice, $message, $propertyPath);
        }
    }

    /**
     * Determines that the named method is defined in the provided object.
     *
     * @param string $value
     * @param mixed  $object
     * @param null   $message
     * @param null   $propertyPath
     *
     * @throws
     */
    public static function methodExists($value, $object, $message = null, $propertyPath = null)
    {
        self::isObject($object, $message, $propertyPath);

        if (!method_exists($object, $value)) {
            $message = sprintf(
                $message ?: 'Expected "%s" does not a exist in provided object.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_METHOD, $propertyPath);
        }
    }

    /**
     * Determines that the provided value is an object.
     *
     * @param mixed $value
     * @param null  $message
     * @param null  $propertyPath
     */
    public static function isObject($value, $message = null, $propertyPath = null)
    {
        if (!is_object($value)) {
            $message = sprintf(
                $message ?: 'Provided "%s" is not a valid object.',
                self::stringify($value)
            );

            throw static::createException($value, $message, static::INVALID_OBJECT, $propertyPath);

        }
    }

    /**
     * Make a string version of a value.
     *
     * @param mixed $value
     * @return string
     */
    private static function stringify($value)
    {
        if (is_bool($value)) {
            return $value ? '<TRUE>' : '<FALSE>';
        }

        if (is_scalar($value)) {
            $val = (string)$value;

            if (strlen($val) > 100) {
                $val = substr($val, 0, 97) . '...';
            }

            return $val;
        }

        if (is_array($value)) {
            return '<ARRAY>';
        }

        if (is_object($value)) {
            return get_class($value);
        }

        if (is_resource($value)) {
            return '<RESOURCE>';
        }

        if ($value === NULL) {
            return '<NULL>';
        }

        return 'unknown';
    }
}