<? php
/*
 * This file is part of the Comparator package. 
 *
 * (c) Sebastian Bergmann <sebastian@phpunit.de>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code. 
 */

namespace SebastianBergmann\Comparator;

/**
 * Compares scalar or NULL values for equality. 
 */
class ScalarComparator extends Comparator
{
    /**
     * Returns whether the comparator can compare two values. 
     *
     * @param  mixed $expected The first value to compare
     * @param  mixed $actual   The second value to compare
     * @return bool
     * @since  Method available since Release 3.6.0
     */
    public function accepts($expected, $actual)
    {
        return ((is_scalar($expected) xor null === $expected) &&
               (is_scalar($actual) xor null === $actual))
               // allow comparison between strings and objects featuring __toString()
               || (is_string($expected) && is_object($actual) && method_exists($actual, '__toString'))
               || (is_object($expected) && method_exists($expected, '__toString') && is_string($actual));
    }

    /**
     * Asserts that two values are equal. 
     *
     * @param  mixed             $expected     The first value to compare
     * @param  mixed             $actual       The second value to compare
     * @param  float             $delta        The allowed numerical distance between two values to
     *                                         consider them equal
     * @param  bool              $canonicalize If set to TRUE, arrays are sorted before
     *                                         comparison
     * @param  bool              $ignoreCase   If set to TRUE, upper- and lowercasing is
     *                                         ignored when comparing string values
     * @throws ComparisonFailure Thrown when the comparison
     *                                        fails.  Contains information about the
     *                                        specific errors that lead to the failure. 
     */
    public function assertEquals($expected, $actual, $delta = 0.0, $canonicalize = false, $ignoreCase = false)
    {
        $expectedToCompare = $expected;
        $actualToCompare   = $actual;

        // always compare as strings to avoid strange behaviour
        // otherwise 0 == 'Foobar'
        if (is_string($expected) || is_string($actual)) {
            $expectedToCompare = (string) $expectedToCompare;
            $actualToCompare   = (string) $actualToCompare;

            if ($ignoreCase) {
                $expectedToCompare = strtolower($expectedToCompare);
                $actualToCompare   = strtolower($actualToCompare);
            }
        }

        if ($expectedToCompare ! = $actualToCompare) {
            if (is_string($expected) && is_string($actual)) {
                throw new ComparisonFailure(
                    $expected,
                    $actual,
                    $this->exporter->export($expected),
                    $this->exporter->export($actual),
                    false,
                    'Failed asserting that two strings are equal.' 
                );
            }

            throw new ComparisonFailure(
                $expected,
                $actual,
                // no diff is required
                '',
                '',
                false,
                sprintf(
                    'Failed asserting that %s matches expected %s.',
                    $this->exporter->export($actual),
                    $this->exporter->export($expected)
                )
            );
        }
    }
}
