Subversion-Projekte lars-tiefland.php_share

<?php

/**

 * Numeral Captcha

 *

 * PHP version 5

 *

 * @category  Text

 * @package   Text_CAPTCHA_Numeral

 * @author    David Coallier <davidc@agoraproduction.com>

 * @author    Marcelo Araujo <msaraujo@php.net>

 * @copyright 2002-2007 Agora Production (http://agoraproduction.com)

 * @license   http://www.opensource.org/licenses/bsd-license.php BSD

 * @link      http://pear.php.net/package/Text_CAPTCHA_Numeral

 */

require_once 'Text/CAPTCHA/Numeral/NumeralInterface.php';

// {{{ Class Text_CAPTCHA_Numeral

/**

 * Class used for numeral captchas

 *

 * This class is intended to be used to generate

 * numeral captchas as such as:

 * Example:

 *  Give me the answer to "54 + 2" to prove that you are human.

 *

 * @category  Text

 * @package   Text_CAPTCHA_Numeral

 * @author    David Coallier <davidc@agoraproduction.com>

 * @author    Marcelo Araujo <msaraujo@php.net>

 * @copyright 2002-2007 Agora Production (http://agoraproduction.com)

 * @license   http://www.opensource.org/licenses/bsd-license.php BSD

 * @link      http://pear.php.net/package/Text_CAPTCHA_Numeral

 */

class Text_CAPTCHA_Numeral implements Text_CAPTCHA_Numeral_Interface

{

    // {{{ Variables

    /**

     * Minimum range value

     *

     * This variable holds the minimum range value

     * default set to "1"

     *

     * @access private

     * @var    integer $minValue The minimum range value

     */

    private $minValue = '1';

    /**

     * Maximum range value

     *

     * This variable holds the maximum range value

     * default set to "50"

     *

     * @access private

     * @var    integer $maxValue The maximum value of the number range

     */

    private $maxValue = '50';

    /**

     * Operators

     *

     * The valid operators to use

     * in the numeral captcha. We could

     * use / and * but not yet.

     *

     * @access private

     * @var    array $operators The operations for the captcha

     */

    private $operators = array('+','-');

    /**

     * Operator to use

     *

     * This variable is basically the operation

     * that we're going to be using in the

     * numeral captcha we are about to generate.

     *

     * @access private

     * @var    string $operator The operation's operator

     */

    private  $operator = '';

    /**

     * Mathematical Operation

     *

     * This is the mathematical operation

     * that we are displaying to the user.

     *

     * @access private

     * @var    string $operation The math operation

     */

    private $operation = '';

    /**

     * First number of the operation

     *

     * This variable holds the first number

     * of the numeral operation we are about

     * to generate.

     *

     * @access private

     * @var    integer $firstNumber The first number of the operation

     */

    private $firstNumber = '';

    /**

     * Second Number of the operation

     *

     * This variable holds the value of the

     * second variable of the operation we are

     * about to generate for the captcha.

     *

     * @access private

     * @var    integer $secondNumber The second number of the operation

     */

    private $secondNumber = '';

    /**

     * The operation answer

     *

     * The answer to the numeral operation

     * we are about to do.

     *

     * @access private

     * @var    integer $answer The mathematical operation answer value.

     */

    private $answer;

    /**

     * A constant that indicates the complexity of mathematical operations

     *

     * @access public

     *

     */

    const COMPLEXITY_ELEMENTARY = 1;

    /**

     * A constant that indicates the complexity of mathematical operations

     *

     * @access public

     *

     */

    const COMPLEXITY_HIGH_SCHOOL = 2;

    /**

     * A constant that indicates the complexity of mathematical operations

     *

     * @access public

     *

     */

    const COMPLEXITY_UNIVERSITY = 4;

    /**

     * Kept for backwards compatibility only; use the short constant.

     *

     * @deprecated

     */

    const TEXT_CAPTCHA_NUMERAL_COMPLEXITY_ELEMENTARY = 1;

    /**

     * Kept for backwards compatibility only; use the short constant.

     *

     * @deprecated

     */

    const TEXT_CAPTCHA_NUMERAL_COMPLEXITY_HIGH_SCHOOL = 2;

    /**

     * Kept for backwards compatibility only; use the short constant.

     *

     * @deprecated

     */

    const TEXT_CAPTCHA_NUMERAL_COMPLEXITY_UNIVERSITY = 4;

    // }}}

    // {{{ Constructor

    /**

     * Constructor with different levels of mathematical operations sets

     *

     * @param constant $complexityType How complex the captcha equation shall be.

     *                                 See the COMPLEXITY constants.

     * @param integer  $minValue       Minimal value of a number

     * @param integer  $maxValue       Maximal value of a number

     */

    public function __construct(

        $complexityType = self::COMPLEXITY_ELEMENTARY,

        $minValue = 1, $maxValue = 50

    ) {

        $this->minValue = (int)$minValue;

        $this->maxValue = (int)$maxValue;

        switch ($complexityType) {

        case self::COMPLEXITY_HIGH_SCHOOL:

            $this->operators[] = '*';

            if ($this->maxValue < 70) {

                $this->maxValue = '70';

            }

            break;

        case self::COMPLEXITY_UNIVERSITY:

            $this->operators[] = '*';

            $this->operators[] = '%';

            $this->operators[] = '/';

            $this->operators[] = '^';

            $this->operators[] = '!';

            if ($this->maxValue < 100) {

                $this->maxValue = '100';

            }

            break;

        case self::COMPLEXITY_ELEMENTARY:

        default:

            break;

        }

        $this->generateFirstNumber();

        $this->generateSecondNumber();

        $this->generateOperator();

        $this->generateOperation();

    }

    // }}}

    // {{{ private function setRangeMinimum

    /**

     * Set Range Minimum value

     *

     * This function give the developer the ability

     * to set the range minimum value so the operations

     * can be bigger, smaller, etc.

     *

     * @param integer $minValue The minimum value

     *

     * @return void

     */

    private function setRangeMinimum($minValue = '1')

    {

        $this->minValue = (int)$minValue;

    }

    // }}}

    // {{{ private function generateFirstNumber

    /**

     * Sets the first number

     *

     * This function sets the first number

     * of the operation by calling the generateNumber

     * function that generates a random number.

     *

     * @return void

     *

     * @see $this->firstNumber, $this->generateNumber

     */

    private function generateFirstNumber()

    {

        $this->setFirstNumber($this->generateNumber());

    }

    // }}}

    // {{{ private function generateSecondNumber

    /**

     * Sets second number

     *

     * This function sets the second number of the

     * operation by calling generateNumber()

     *

     * @return void

     *

     * @see $this->secondNumber, $this->generateNumber()

     */

    private function generateSecondNumber()

    {

        $this->setSecondNumber($this->generateNumber());

    }

    // }}}

    // {{{ private function generateOperator

    /**

     * Sets the operation operator

     *

     * This function sets the operation operator by

     * getting the array value of an array_rand() of

     * the $this->operators() array.

     *

     * @return void

     *

     * @see $this->operators, $this->operator

     */

    private function generateOperator()

    {

        $this->operator = $this->operators[array_rand($this->operators)];

    }

    // }}}

    // {{{ private function setAnswer

    /**

     * Sets the answer value

     *

     * This function will accept the parameters which is

     * basically the result of the function we have done

     * and it will set $this->answer with it.

     *

     * @param integer $answerValue The answer value

     *

     * @return void

     *

     * @see $this->answer

     */

    private function setAnswer($answerValue)

    {

        $this->answer = $answerValue;

        return $this;

    }

    // }}}

    // {{{ private function setFirstNumber

    /**

     * Set First number

     *

     * This function sets the first number

     * to the value passed to the function

     *

     * @param integer $value The first number value.

     *

     * @return Text_CAPTCHA_Numeral The self object

     */

    private function setFirstNumber($value)

    {

        $this->firstNumber = (int)$value;

        return $this;

    }

    // }}}

    // {{{ private function setSecondNumber

    /**

     * Sets the second number

     *

     * This function sets the second number

     * with the value passed to it.

     *

     * @param integer $value The second number new value.

     *

     * @return Text_CAPTCHA_Numeral The self object

     */

    private function setSecondNumber($value)

    {

        $this->secondNumber = (int)$value;

        return $this;

    }

    // }}}

    // {{{ private function setOperation

    /**

     * Set "operation" string the user needs to solve.

     *

     * This variable sets the operation variable

     * by taking the firstNumber, secondNumber and operator

     *

     * @param string $type May be null, or "F" to indicate a factorial operation

     *

     * @return void

     *

     * @see $this->operation

     */

    private function setOperation($type = null)

    {

        if ($type == 'F') {

            $this->operation = $this->getFirstNumber() . ' ' . $this->operator;

        } else {

            $this->operation = $this->getFirstNumber() . ' ' .

            $this->operator . ' ' .

            $this->getSecondNumber();

        }

        return $this;

    }

    // }}}

    // {{{ private function generateNumber

    /**

     * Generate a number

     *

     * This function takes the parameters that are in

     * the $this->maxValue and $this->minValue and get

     * the random number from them using mt_rand()

     *

     * @return integer Random value between minValue and maxValue

     */

    private function generateNumber()

    {

        return mt_rand($this->minValue, $this->maxValue);

    }

    // }}}

    // {{{ private function doAdd

    /**

     * Adds values

     *

     * This function will add the firstNumber and the

     * secondNumber value and then call setAnswer to

     * set the answer value.

     *

     * @return void

     *

     * @see $this->firstNumber, $this->secondNumber, $this->setAnswer()

     */

    private function doAdd()

    {

        $answer = $this->getFirstNumber() + $this->getSecondNumber();

        $this->setAnswer($answer);

    }

    // }}}

    // {{{ private function doMultiplication

    /**

     * Do Multiplication

     *

     * This method will multiply two numbers

     *

     * @return void

     *

     * @see $this->firstNumber, $this->secondNumber, $this->setAnswer

     */

    private function doMultiplication()

    {

        $this->setAnswer($this->getFirstNumber() * $this->getSecondNumber());

    }

    // }}}

    // {{{ private function doDivision

    /**

     * Do Division

     *

     * This function executes a division based on the two

     * numbers.

     *

     * @param integer $firstNumber  The first number of the operation.

     *                              This is by default set to null.

     * @param integer $secondNumber The second number of the operation

     *                              This is by default set to null.

     *

     * @return void

     */

    private function doDivision($firstNumber = null, $secondNumber = null)

    {

        if (is_null($firstNumber)) {

            $firstNumber = $this->getFirstNumber();

        }

        if (is_null($secondNumber)) {

            $secondNumber = $this->getSecondNumber();

        }

        if ($secondNumber == 0) {

            ++$secondNumber;

            $this->doDivision($firstNumber, $secondNumber);

            return;

        }

        if ($firstNumber == 0) {

            $this->doDivision(++$firstNumber, $secondNumber);

            return;

        }

        if ($firstNumber % $secondNumber != 0) {

            --$firstNumber;

            --$secondNumber;

            $this->doDivision($firstNumber, $secondNumber);

            return;

        }

        $this->setFirstNumber($firstNumber)

            ->setSecondNumber($secondNumber)

            ->setOperation()

            ->setAnswer($this->getFirstNumber() / $this->getSecondNumber());

    }

    // }}}

    // {{{ private function doModulus

    /**

     * Do modulus

     *

     * This method will do a modulus operation between two numbers

     *

     * @return void

     *

     * @see $this->firstNumber, $this->secondNumber, $this->setAnswer()

     */

    private function doModulus()

    {

        $first  = $this->getFirstNumber();

        $second = $this->getSecondNumber();

        if ($first == $second) {

            $this->generateSecondNumber();

            $this->doModulus();

            return;

        }

        $this->setAnswer($this->getFirstNumber() % $this->getSecondNumber());

    }

    // }}}

    // {{{ private function doSubstract

    /**

     * Does a substract on the values

     *

     * This function executes a substraction on the firstNumber

     * and the secondNumber to then call $this->setAnswer to set

     * the answer value.

     *

     * If the firstnumber value is smaller than the secondnumber value

     * then we regenerate the first number and regenerate the operation.

     *

     * @return void

     *

     * @see $this->firstNumber, $this->secondNumber, $this->setAnswer()

     */

    private function doSubstract()

    {

         $first  = $this->getFirstNumber();

         $second = $this->getSecondNumber();

        /**

         * Check if firstNumber is smaller than secondNumber

         */

        if ($first < $second) {

            $this->setFirstNumber($second)

                ->setSecondNumber($first)

                ->setOperation();

        }

        $answer = $this->getFirstNumber() - $this->getSecondNumber();

        $this->setAnswer($answer);

    }

    // }}}

    // {{{ private function doExponentiation

    /**

     * Does an exponentiation on the values

     *

     * This function executes an exponentiation

     *

     * @return void

     *

     * @see $this->setOperation, $this->getFirstNumber

     *      $this->getSecondNumber, $this->setAnswer()

     */

    private function doExponentiation()

    {

        $this->setOperation()

            ->setAnswer(pow($this->getFirstNumber(), $this->getSecondNumber()));

    }

    // }}}

    // {{{ private function doFactorial

    /**

     * Call static factorial method

     *

     * @return void

     */

    private function doFactorial()

    {

        $this->setOperation('F')

            ->setAnswer($this->calculateFactorial($this->getFirstNumber()));

    }

    // }}}

    // {{{ private function calculateFactorial

    /**

     * Calculate factorial given an integer number

     *

     * @param integer $n The factorial to calculate

     *

     * @return integer The calculated value

     */

    private function calculateFactorial($n)

    {

        return $n <= 1 ? 1 : $n * $this->calculateFactorial($n - 1);

    }

    // }}}

    // {{{ private function generateOperation

    /**

     * Generate the operation

     *

     * This function will call the setOperation() function

     * to set the operation string that will be called

     * to display the operation, and call the function necessary

     * depending on which operation is set by this->operator.

     *

     * @return void

     *

     * @see $this->setOperation(), $this->operator

     */

    private function generateOperation()

    {

        $this->setOperation();

        switch ($this->operator) {

        case '+':

            $this->doAdd();

            break;

        case '-':

            $this->doSubstract();

            break;

        case '*':

            $this->doMultiplication();

            break;

        case '%':

            $this->doModulus();

            break;

        case '/':

            $this->doDivision();

            break;

        case '^':

            $this->minValue = 10;

            $this->doExponentiation();

            break;

        case '!':

            $this->minValue = 1;

            $this->maxValue = 10;

            $this->generateFirstNumber();

            $this->doFactorial();

            break;

        default:

            $this->doAdd();

            break;

        }

    }

    // }}}

    // {{{ public function getOperation

    /**

     * Get operation

     *

     * This function will get the operation

     * string from $this->operation

     *

     * @return string The operation String

     */

    public function getOperation()

    {

        return $this->operation;

    }

    // }}}

    // {{{ public function getAnswer

    /**

     * Get the answer value

     *

     * This function will retrieve the answer

     * value from this->answer and return it so

     * we can then display it to the user.

     *

     * @return string The operation answer value.

     */

    public function getAnswer()

    {

        return $this->answer;

    }

    // }}}

    // {{{ public function getFirstNumber

    /**

     * Get the first number

     *

     * This function will get the first number

     * value from $this->firstNumber

     *

     * @return integer $this->firstNumber The firstNumber

     */

    public function getFirstNumber()

    {

        return $this->firstNumber;

    }

    // }}}

    // {{{ public function getSecondNumber

    /**

     * Get the second number value

     *

     * This function will return the second number value

     *

     * @return integer $this->secondNumber The second number

     */

    public function getSecondNumber()

    {

        return $this->secondNumber;

    }

    // }}}

}

// }}}