<?php

/*

 * This file is part of the Symfony package.

 * (c) Fabien Potencier <fabien@symfony.com>

 *

 * For the full copyright and license information, please view the LICENSE

 * file that was distributed with this source code.

 */

namespace Symfony\Component\Yaml;

use Symfony\Component\Yaml\Exception\ParseException;

use Symfony\Component\Yaml\Exception\DumpException;

/**

 * Inline implements a YAML parser/dumper for the YAML inline syntax.

 *

 * @author Fabien Potencier <fabien@symfony.com>

 */

class Inline

{

    const REGEX_QUOTED_STRING = '(?:"([^"\\\\]*(?:\\\\.[^"\\\\]*)*)"|\'([^\']*(?:\'\'[^\']*)*)\')';

    /**

     * Converts a YAML string to a PHP array.

     *

     * @param string $value A YAML string

     *

     * @return array A PHP array representing the YAML string

     */

    static public function parse($value)

    {

        $value = trim($value);

        if (0 == strlen($value)) {

            return '';

        }

        if (function_exists('mb_internal_encoding') && ((int) ini_get('mbstring.func_overload')) & 2) {

            $mbEncoding = mb_internal_encoding();

            mb_internal_encoding('ASCII');

        }

        switch ($value[0]) {

            case '[':

                $result = self::parseSequence($value);

                break;

            case '{':

                $result = self::parseMapping($value);

                break;

            default:

                $result = self::parseScalar($value);

        }

        if (isset($mbEncoding)) {

            mb_internal_encoding($mbEncoding);

        }

        return $result;

    }

    /**

     * Dumps a given PHP variable to a YAML string.

     *

     * @param mixed $value The PHP variable to convert

     *

     * @return string The YAML string representing the PHP array

     *

     * @throws DumpException When trying to dump PHP resource

     */

    static public function dump($value)

    {

        switch (true) {

            case is_resource($value):

                throw new DumpException(sprintf('Unable to dump PHP resources in a YAML file ("%s").', get_resource_type($value)));

            case is_object($value):

                return '!!php/object:'.serialize($value);

            case is_array($value):

                return self::dumpArray($value);

            case null === $value:

                return 'null';

            case true === $value:

                return 'true';

            case false === $value:

                return 'false';

            case ctype_digit($value):

                return is_string($value) ? "'$value'" : (int) $value;

            case is_numeric($value):

                return is_string($value) ? "'$value'" : (is_infinite($value) ? str_ireplace('INF', '.Inf', strval($value)) : $value);

            case Escaper::requiresDoubleQuoting($value):

                return Escaper::escapeWithDoubleQuotes($value);

            case Escaper::requiresSingleQuoting($value):

                return Escaper::escapeWithSingleQuotes($value);

            case '' == $value:

                return "''";

            case preg_match(self::getTimestampRegex(), $value):

            case in_array(strtolower($value), array('null', '~', 'true', 'false')):

                return "'$value'";

            default:

                return $value;

        }

    }

    /**

     * Dumps a PHP array to a YAML string.

     *

     * @param array $value The PHP array to dump

     *

     * @return string The YAML string representing the PHP array

     */

    static private function dumpArray($value)

    {

        // array

        $keys = array_keys($value);

        if ((1 == count($keys) && '0' == $keys[0])

            || (count($keys) > 1 && array_reduce($keys, function ($v, $w) { return (integer) $v + $w; }, 0) == count($keys) * (count($keys) - 1) / 2)

        ) {

            $output = array();

            foreach ($value as $val) {

                $output[] = self::dump($val);

            }

            return sprintf('[%s]', implode(', ', $output));

        }

        // mapping

        $output = array();

        foreach ($value as $key => $val) {

            $output[] = sprintf('%s: %s', self::dump($key), self::dump($val));

        }

        return sprintf('{ %s }', implode(', ', $output));

    }

    /**

     * Parses a scalar to a YAML string.

     *

     * @param scalar  $scalar

     * @param string  $delimiters

     * @param array   $stringDelimiters

     * @param integer &$i

     * @param Boolean $evaluate

     *

     * @return string A YAML string

     *

     * @throws ParseException When malformed inline YAML string is parsed

     */

    static public function parseScalar($scalar, $delimiters = null, $stringDelimiters = array('"', "'"), &$i = 0, $evaluate = true)

    {

        if (in_array($scalar[$i], $stringDelimiters)) {

            // quoted scalar

            $output = self::parseQuotedScalar($scalar, $i);

        } else {

            // "normal" string

            if (!$delimiters) {

                $output = substr($scalar, $i);

                $i += strlen($output);

                // remove comments

                if (false !== $strpos = strpos($output, ' #')) {

                    $output = rtrim(substr($output, 0, $strpos));

                }

            } else if (preg_match('/^(.+?)('.implode('|', $delimiters).')/', substr($scalar, $i), $match)) {

                $output = $match[1];

                $i += strlen($output);

            } else {

                throw new ParseException(sprintf('Malformed inline YAML string (%s).', $scalar));

            }

            $output = $evaluate ? self::evaluateScalar($output) : $output;

        }

        return $output;

    }

    /**

     * Parses a quoted scalar to YAML.

     *

     * @param string  $scalar

     * @param integer $i

     *

     * @return string A YAML string

     *

     * @throws ParseException When malformed inline YAML string is parsed

     */

    static private function parseQuotedScalar($scalar, &$i)

    {

        if (!preg_match('/'.self::REGEX_QUOTED_STRING.'/Au', substr($scalar, $i), $match)) {

            throw new ParseException(sprintf('Malformed inline YAML string (%s).', substr($scalar, $i)));

        }

        $output = substr($match[0], 1, strlen($match[0]) - 2);

        $unescaper = new Unescaper();

        if ('"' == $scalar[$i]) {

            $output = $unescaper->unescapeDoubleQuotedString($output);

        } else {

            $output = $unescaper->unescapeSingleQuotedString($output);

        }

        $i += strlen($match[0]);

        return $output;

    }

    /**

     * Parses a sequence to a YAML string.

     *

     * @param string  $sequence

     * @param integer $i

     *

     * @return string A YAML string

     *

     * @throws ParseException When malformed inline YAML string is parsed

     */

    static private function parseSequence($sequence, &$i = 0)

    {

        $output = array();

        $len = strlen($sequence);

        $i += 1;

        // [foo, bar, ...]

        while ($i < $len) {

            switch ($sequence[$i]) {

                case '[':

                    // nested sequence

                    $output[] = self::parseSequence($sequence, $i);

                    break;

                case '{':

                    // nested mapping

                    $output[] = self::parseMapping($sequence, $i);

                    break;

                case ']':

                    return $output;

                case ',':

                case ' ':

                    break;

                default:

                    $isQuoted = in_array($sequence[$i], array('"', "'"));

                    $value = self::parseScalar($sequence, array(',', ']'), array('"', "'"), $i);

                    if (!$isQuoted && false !== strpos($value, ': ')) {

                        // embedded mapping?

                        try {

                            $value = self::parseMapping('{'.$value.'}');

                        } catch (\InvalidArgumentException $e) {

                            // no, it's not

                        }

                    }

                    $output[] = $value;

                    --$i;

            }

            ++$i;

        }

        throw new ParseException(sprintf('Malformed inline YAML string %s', $sequence));

    }

    /**

     * Parses a mapping to a YAML string.

     *

     * @param string  $mapping

     * @param integer $i

     *

     * @return string A YAML string

     *

     * @throws ParseException When malformed inline YAML string is parsed

     */

    static private function parseMapping($mapping, &$i = 0)

    {

        $output = array();

        $len = strlen($mapping);

        $i += 1;

        // {foo: bar, bar:foo, ...}

        while ($i < $len) {

            switch ($mapping[$i]) {

                case ' ':

                case ',':

                    ++$i;

                    continue 2;

                case '}':

                    return $output;

            }

            // key

            $key = self::parseScalar($mapping, array(':', ' '), array('"', "'"), $i, false);

            // value

            $done = false;

            while ($i < $len) {

                switch ($mapping[$i]) {

                    case '[':

                        // nested sequence

                        $output[$key] = self::parseSequence($mapping, $i);

                        $done = true;

                        break;

                    case '{':

                        // nested mapping

                        $output[$key] = self::parseMapping($mapping, $i);

                        $done = true;

                        break;

                    case ':':

                    case ' ':

                        break;

                    default:

                        $output[$key] = self::parseScalar($mapping, array(',', '}'), array('"', "'"), $i);

                        $done = true;

                        --$i;

                }

                ++$i;

                if ($done) {

                    continue 2;

                }

            }

        }

        throw new ParseException(sprintf('Malformed inline YAML string %s', $mapping));

    }

    /**

     * Evaluates scalars and replaces magic values.

     *

     * @param string $scalar

     *

     * @return string A YAML string

     */

    static private function evaluateScalar($scalar)

    {

        $scalar = trim($scalar);

        switch (true) {

            case 'null' == strtolower($scalar):

            case '' == $scalar:

            case '~' == $scalar:

                return null;

            case 0 === strpos($scalar, '!str'):

                return (string) substr($scalar, 5);

            case 0 === strpos($scalar, '! '):

                return intval(self::parseScalar(substr($scalar, 2)));

            case 0 === strpos($scalar, '!!php/object:'):

                return unserialize(substr($scalar, 13));

            case ctype_digit($scalar):

                $raw = $scalar;

                $cast = intval($scalar);

                return '0' == $scalar[0] ? octdec($scalar) : (((string) $raw == (string) $cast) ? $cast : $raw);

            case 'true' === strtolower($scalar):

                return true;

            case 'false' === strtolower($scalar):

                return false;

            case is_numeric($scalar):

                return '0x' == $scalar[0].$scalar[1] ? hexdec($scalar) : floatval($scalar);

            case 0 == strcasecmp($scalar, '.inf'):

            case 0 == strcasecmp($scalar, '.NaN'):

                return -log(0);

            case 0 == strcasecmp($scalar, '-.inf'):

                return log(0);

            case preg_match('/^(-|\+)?[0-9,]+(\.[0-9]+)?$/', $scalar):

                return floatval(str_replace(',', '', $scalar));

            case preg_match(self::getTimestampRegex(), $scalar):

                return strtotime($scalar);

            default:

                return (string) $scalar;

        }

    }

    /**

     * Gets a regex that matches an unix timestamp

     *

     * @return string The regular expression

     */

    static private function getTimestampRegex()

    {

        return <<<EOF

        ~^

        (?P<year>[0-9][0-9][0-9][0-9])

        -(?P<month>[0-9][0-9]?)

        -(?P<day>[0-9][0-9]?)

        (?:(?:[Tt]|[ \t]+)

        (?P<hour>[0-9][0-9]?)

        :(?P<minute>[0-9][0-9])

        :(?P<second>[0-9][0-9])

        (?:\.(?P<fraction>[0-9]*))?

        (?:[ \t]*(?P<tz>Z|(?P<tz_sign>[-+])(?P<tz_hour>[0-9][0-9]?)

        (?::(?P<tz_minute>[0-9][0-9]))?))?)?

        $~x

EOF;

    }

}