<?php
/**
 * This file is part of phpDocumentor.
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 *
 * @copyright 2010-2015 Mike van Riel<mike@phpdoc.org>
 * @license   http://www.opensource.org/licenses/mit-license.php MIT
 * @link      http://phpdoc.org
 */

namespace phpDocumentor\Reflection\DocBlock\Tags;

use phpDocumentor\Reflection\DocBlock\Description;
use phpDocumentor\Reflection\DocBlock\DescriptionFactory;
use phpDocumentor\Reflection\Type;
use phpDocumentor\Reflection\TypeResolver;
use phpDocumentor\Reflection\Types\Context as TypeContext;
use Webmozart\Assert\Assert;

/**
 * Reflection class for a {@}var tag in a Docblock.
 */
class Var_ extends BaseTag implements Factory\StaticMethod
{
    /** @var string */
    protected $name = 'var';

    /** @var Type */
    private $type;

    /** @var string */
    protected $variableName = '';

    /**
     * @param string      $variableName
     * @param Type        $type
     * @param Description $description
     */
    public function __construct($variableName, Type $type = null, Description $description = null)
    {
        Assert::string($variableName);

        $this->variableName = $variableName;
        $this->type         = $type;
        $this->description  = $description;
    }

    /**
     * {@inheritdoc}
     */
    public static function create(
        $body,
        TypeResolver $typeResolver = null,
        DescriptionFactory $descriptionFactory = null,
        TypeContext $context = null
    ) {
        Assert::stringNotEmpty($body);
        Assert::allNotNull([$typeResolver, $descriptionFactory]);

        $parts        = preg_split('/(\s+)/Su', $body, 3, PREG_SPLIT_DELIM_CAPTURE);
        $type         = null;
        $variableName = '';

        // if the first item that is encountered is not a variable; it is a type
        if (isset($parts[0]) && (strlen($parts[0]) > 0) && ($parts[0][0] !== '$')) {
            $type = $typeResolver->resolve(array_shift($parts), $context);
            array_shift($parts);
        }

        // if the next item starts with a $ or ...$ it must be the variable name
        if (isset($parts[0]) && (strlen($parts[0]) > 0) && ($parts[0][0] === '$')) {
            $variableName = array_shift($parts);
            array_shift($parts);

            if (substr($variableName, 0, 1) === '$') {
                $variableName = substr($variableName, 1);
            }
        }

        $description = $descriptionFactory->create(implode('', $parts), $context);

        return new static($variableName, $type, $description);
    }

    /**
     * Returns the variable's name.
     *
     * @return string
     */
    public function getVariableName()
    {
        return $this->variableName;
    }

    /**
     * Returns the variable's type or null if unknown.
     *
     * @return Type|null
     */
    public function getType()
    {
        return $this->type;
    }

    /**
     * Returns a string representation for this tag.
     *
     * @return string
     */
    public function __toString()
    {
        return ($this->type ? $this->type . ' ' : '')
            . (empty($this->variableName) ? null : ('$' . $this->variableName))
            . ($this->description ? ' ' . $this->description : '');
    }
}
