DocInject trait

DocInject.trait.php

<?php
trait DocInject
{
    public function parseDocInject()
    {
        $reflection = new ReflectionClass($this);
        foreach ($reflection->getProperties() as $property) {
            $this->processProperty($property);
        }
    }

    private function processProperty(ReflectionProperty $property)
    {
        $docComment = $this->cleanPhpDoc($property->getDocComment());
        foreach (explode("\n", $docComment) as $item) {
            if ($this->existsInjectDecorator($item)) {
                $this->performDependencyInjection($property, $item);
            }
        }
    }

    private function cleanPhpDoc($docComment)
    {
        $docComment = preg_replace('#[ \t]*(?:\/\*\*|\*\/|\*)?[ ]{0,1}(.*)?#', '$1', $docComment);
        $docComment = trim(str_replace('*/', null, $docComment));
        return $docComment;
    }

    private function existsInjectDecorator($item)
    {
        return strpos($item, '@inject') !== false;
    }

    private function performDependencyInjection(ReflectionProperty $property, $item)
    {
        $injectString = $this->removeDecoratorFromPhpDoc($item);
        $value = $this->compileInjectString($injectString);
        $this->injectValueIntoProperty($property, $value);
    }

    private function removeDecoratorFromPhpDoc($item)
    {
        return trim(str_replace('@inject', null, $item));
    }

    private function compileInjectString($injectString)
    {
        $value = null;
        eval("\$value = {$injectString};"); // yes, eval. uggly, isnt't?
        return $value;
    }

    private function injectValueIntoProperty(ReflectionProperty $property, $value)
    {
        $property->setAccessible(true);
        $property->setValue($this, $value);
    }
}