<?php

/*

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 *

 * This software consists of voluntary contributions made by many individuals

 * and is licensed under the LGPL. For more information, see

 * <http://www.doctrine-project.org>.

 */

namespace Doctrine\Common\Annotations;

/**

 * Parses a file for namespaces/use/class declarations.

 *

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

 */

final class PhpParser

{

    private $tokens;

    /**

     * Parses a class.

     *

     * @param \ReflectionClass $class

     */

    public function parseClass(\ReflectionClass $class)

    {

        if (false === $filename = $class->getFilename()) {

            return array();

        }

        $src = file_get_contents($filename);

        $name = $class->getName();

        // This is a short-cut for code that follows some conventions:

        // - namespaced

        // - one class per file

        if (preg_match_all('#\bnamespace\s+'.str_replace('\\', '\\\\', $class->getNamespaceName()).'\s*;.*?\b(?:class|interface)\s+'.$class->getShortName().'\b#s', $src, $matches)) {

            foreach ($matches[0] as $match) {

                $classes = $this->parse('<?php '.$match, $name);

                if (isset($classes[$name])) {

                    return $classes[$name];

                }

            }

        }

        $classes = $this->parse($src, $name);

        return $classes[$name];

    }

    private function parse($src, $interestedClass = null)

    {

        $this->tokens = token_get_all($src);

        $classes = $uses = array();

        $namespace = '';

        while ($token = $this->next()) {

            if (T_NAMESPACE === $token[0]) {

                $namespace = $this->parseNamespace();

                $uses = array();

            } elseif (T_CLASS === $token[0] || T_INTERFACE === $token[0]) {

                if ('' !== $namespace) {

                    $class = $namespace.'\\'.$this->nextValue();

                } else {

                    $class = $this->nextValue();

                }

                $classes[$class] = $uses;

                if (null !== $interestedClass && $interestedClass === $class) {

                    return $classes;

                }

            } elseif (T_USE === $token[0]) {

                foreach ($this->parseUseStatement() as $useStatement) {

                    list($alias, $class) = $useStatement;

                    $uses[strtolower($alias)] = $class;

                }

            }

        }

        return $classes;

    }

    private function parseNamespace()

    {

        $namespace = '';

        while ($token = $this->next()) {

            if (T_NS_SEPARATOR === $token[0] || T_STRING === $token[0]) {

                $namespace .= $token[1];

            } elseif (is_string($token) && in_array($token, array(';', '{'))) {

                return $namespace;

            }

        }

    }

    private function parseUseStatement()

    {

        $statements = $class = array();

        $alias = '';

        while ($token = $this->next()) {

            if (T_NS_SEPARATOR === $token[0] || T_STRING === $token[0]) {

                $class[] = $token[1];

            } else if (T_AS === $token[0]) {

                $alias = $this->nextValue();

            } else if (is_string($token)) {

                if (',' === $token || ';' === $token) {

                    $statements[] = array(

                        $alias ? $alias : $class[count($class) - 1],

                        implode('', $class)

                    );

                }

                if (';' === $token) {

                    return $statements;

                }

                if (',' === $token) {

                    $class = array();

                    $alias = '';

                    continue;

                }

            }

        }

    }

    private function next()

    {

        while ($token = array_shift($this->tokens)) {

            if (in_array($token[0], array(T_WHITESPACE, T_COMMENT, T_DOC_COMMENT))) {

                continue;

            }

            return $token;

        }

    }

    private function nextValue()

    {

        $token = $this->next();

        return is_array($token) ? $token[1] : $token;

    }

}