<?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 MIT license. For more information, see
 * <http://www.doctrine-project.org>.
 */

namespace Doctrine\Common\Reflection;

/**
 * Finds a class in a PSR-0 structure.
 *
 * @author Karoly Negyesi <karoly@negyesi.net>
 */
class Psr0FindFile implements ClassFinderInterface
{
    /**
     * The PSR-0 prefixes.
     *
     * @var string
     */
    protected $prefixes;

    /**
     * @param string $prefixes
     *     An array of prefixes. Each key is a PHP namespace and each value is
     *     a list of directories.
     */
    public function __construct($prefixes)
    {
        $this->prefixes = $prefixes;
    }

    /**
     * Finds a class.
     *
     * @param string $class The name of the class.
     *
     * @return
     *     The name of the class or NULL if not found.
     */
    public function findFile($class)
    {
        $lastNsPos = strrpos($class, '\\');
        if ('\\' == $class[0]) {
            $class = substr($class, 1);
        }

        if (false !== $lastNsPos) {
            // namespaced class name
            $classPath = str_replace('\\', DIRECTORY_SEPARATOR, substr($class, 0, $lastNsPos)) . DIRECTORY_SEPARATOR;
            $className = substr($class, $lastNsPos + 1);
        } else {
            // PEAR-like class name
            $classPath = null;
            $className = $class;
        }

        $classPath .= str_replace('_', DIRECTORY_SEPARATOR, $className) . '.php';

        foreach ($this->prefixes as $prefix => $dirs) {
            if (0 === strpos($class, $prefix)) {
                foreach ($dirs as $dir) {
                    if (file_exists($dir . DIRECTORY_SEPARATOR . $classPath)) {
                        return $dir . DIRECTORY_SEPARATOR . $classPath;
                    }
                }
            }
        }
    }
}