<?php

/*
 * © 2016 IRSTEA
 * Guillaume Perréal <guillaume.perreal@irstea.fr>
 * Tous droits réservés.
 */

namespace Irstea\PlantUmlBundle\Model;

use Irstea\PlantUmlBundle\Model\Node\Class_;
use Irstea\PlantUmlBundle\Model\Node\Interface_;
use Irstea\PlantUmlBundle\Model\Node\Trait_;
use Irstea\PlantUmlBundle\Writer\WritableInterface;
use Irstea\PlantUmlBundle\Writer\WritableNodeInterface;
use Irstea\PlantUmlBundle\Writer\WriterInterface;
use ReflectionClass;

/**
 * Description of Visitor
 *
 * @author Guillaume Perréal <guillaume.perreal@irstea.fr>
 */
class ClassVisitor implements ClassVisitorInterface, WritableInterface
{
    /**
     * @var RootNamespace
     */
    protected $rootNamespace;

    /**
     * @var ClassFilterInterface
     */
    protected $filter;

    public function __construct(ClassFilterInterface $filter = null)
    {
        $this->rootNamespace = new RootNamespace();
        $this->filter = $filter ?: Filter\AcceptAllFilter::instance();
    }

    /**
     * @param \Irstea\PlantUmlBundle\Model\ClassFilterInterface $filter
     * @return self
     */
    public function setClassFilter(ClassFilterInterface $filter)
    {
        $this->filter = $filter;
        return $this;
    }

    public function visitClass($className)
    {
        assert('is_string($className)', $className);
        if (isset($this->nodes[$className])) {
            return $this->nodes[$className];
        }
        if (!$this->filter->accept($className)) {
            return $this->nodes[$className] = false;
        }

        return $this->doVisitClass($className);
    }

    /**
     *
     * @param string $className
     * @return NodeInterface
     */
    protected function doVisitClass($className)
    {
        $reflection = new ReflectionClass($className);
        return $this->visitClassReflection($reflection);
    }

    /**
     * @param ReflectionClass $class
     * @return NodeInterface
     */
    protected function visitClassReflection(ReflectionClass $class)
    {
        if ($class->isTrait()) {
            $node  = new Trait_($class->getName());
        } elseif ($class->isInterface()) {
            $node  = new Interface_($class->getName());
        } else {
            $node = new Class_($class->getName(), $class->isAbstract(), $class->isFinal());
        }

        $this->nodes[$class->getName()] = $node;

        $namespace = $this->rootNamespace->getNamespace($class->getNamespaceName());
        $namespace->addNode($node);

        $parentClass = $class->getParentClass();
        $traitNames = $class->getTraitNames();

        $indirectInterfaces = array_filter(
                array_map(
                    function ($i) { return $i->getInterfaceNames(); },
                    $class->getInterfaces()
                )
        );
        $interfaceNames = $class->getInterfaceNames();
        if (!empty($indirectInterfaces)) {
            $indirectInterfaces = call_user_func_array('array_merge', $indirectInterfaces);
            $interfaceNames = array_diff($interfaceNames, $indirectInterfaces);
        }

        if ($parentClass) {
            $traitNames = array_diff($traitNames, $parentClass->getTraitNames());
            $interfaceNames = array_diff($interfaceNames, $parentClass->getInterfaceNames());
            $this->visitRelations($node, $namespace, [$parentClass->getName()], 'Irstea\PlantUmlBundle\Model\Arrow\ExtendsClass');
        }

        $this->visitRelations($node, $namespace, $interfaceNames, 'Irstea\PlantUmlBundle\Model\Arrow\ImplementsInterface');
        $this->visitRelations($node, $namespace, $traitNames, 'Irstea\PlantUmlBundle\Model\Arrow\UsesTrait');

        return $node;
    }

    protected function visitRelations(WritableNodeInterface $source, NamespaceInterface $namespace, array $classNames, $relationClass)
    {
        foreach ($classNames as $className) {
            $target = $this->visitClass($className);
            if ($target) {
                $namespace->addArrow(new $relationClass($source, $target));
            }
        }
    }

    public function outputTo(WriterInterface $writer)
    {
        return $this->rootNamespace->outputTo($writer);
    }
}