<?php

/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/

namespace Symfony\Component\Config\Definition\Builder;

/**
* This class provides a fluent interface for building a node.
*
* @author Johannes M. Schmitt <schmittjoh@gmail.com>
*/
class NodeBuilder implements NodeParentInterface
{
protected $parent;
protected $nodeMapping;

public function __construct()
{
$this->nodeMapping = [
'variable' => VariableNodeDefinition::class,
'scalar' => ScalarNodeDefinition::class,
'boolean' => BooleanNodeDefinition::class,
'integer' => IntegerNodeDefinition::class,
'float' => FloatNodeDefinition::class,
'array' => ArrayNodeDefinition::class,
'enum' => EnumNodeDefinition::class,
];
}

/**
* Set the parent node.
*
* @return $this
*/
public function setParent(ParentNodeDefinitionInterface $parent = null)
{
$this->parent = $parent;

return $this;
}

/**
* Creates a child array node.
*
* @param string $name The name of the node
*
* @return ArrayNodeDefinition The child node
*/
public function arrayNode($name)
{
return $this->node($name, 'array');
}

/**
* Creates a child scalar node.
*
* @param string $name The name of the node
*
* @return ScalarNodeDefinition The child node
*/
public function scalarNode($name)
{
return $this->node($name, 'scalar');
}

/**
* Creates a child Boolean node.
*
* @param string $name The name of the node
*
* @return BooleanNodeDefinition The child node
*/
public function booleanNode($name)
{
return $this->node($name, 'boolean');
}

/**
* Creates a child integer node.
*
* @param string $name The name of the node
*
* @return IntegerNodeDefinition The child node
*/
public function integerNode($name)
{
return $this->node($name, 'integer');
}

/**
* Creates a child float node.
*
* @param string $name The name of the node
*
* @return FloatNodeDefinition The child node
*/
public function floatNode($name)
{
return $this->node($name, 'float');
}

/**
* Creates a child EnumNode.
*
* @param string $name
*
* @return EnumNodeDefinition
*/
public function enumNode($name)
{
return $this->node($name, 'enum');
}

/**
* Creates a child variable node.
*
* @param string $name The name of the node
*
* @return VariableNodeDefinition The builder of the child node
*/
public function variableNode($name)
{
return $this->node($name, 'variable');
}

/**
* Returns the parent node.
*
* @return NodeDefinition&ParentNodeDefinitionInterface The parent node
*/
public function end()
{
return $this->parent;
}

/**
* Creates a child node.
*
* @param string|null $name The name of the node
* @param string $type The type of the node
*
* @return NodeDefinition The child node
*
* @throws \RuntimeException When the node type is not registered
* @throws \RuntimeException When the node class is not found
*/
public function node($name, $type)
{
$class = $this->getNodeClass($type);

$node = new $class($name);

$this->append($node);

return $node;
}

/**
* Appends a node definition.
*
* Usage:
*
* $node = new ArrayNodeDefinition('name')
* ->children()
* ->scalarNode('foo')->end()
* ->scalarNode('baz')->end()
* ->append($this->getBarNodeDefinition())
* ->end()
* ;
*
* @return $this
*/
public function append(NodeDefinition $node)
{
if ($node instanceof BuilderAwareInterface) {
$builder = clone $this;
$builder->setParent(null);
$node->setBuilder($builder);
}

if (null !== $this->parent) {
$this->parent->append($node);
// Make this builder the node parent to allow for a fluid interface
$node->setParent($this);
}

return $this;
}

/**
* Adds or overrides a node Type.
*
* @param string $type The name of the type
* @param string $class The fully qualified name the node definition class
*
* @return $this
*/
public function setNodeClass($type, $class)
{
$this->nodeMapping[strtolower($type)] = $class;

return $this;
}

/**
* Returns the class name of the node definition.
*
* @param string $type The node type
*
* @return string The node definition class name
*
* @throws \RuntimeException When the node type is not registered
* @throws \RuntimeException When the node class is not found
*/
protected function getNodeClass($type)
{
$type = strtolower($type);

if (!isset($this->nodeMapping[$type])) {
throw new \RuntimeException(sprintf('The node type "%s" is not registered.', $type));
}

$class = $this->nodeMapping[$type];

if (!class_exists($class)) {
throw new \RuntimeException(sprintf('The node class "%s" does not exist.', $class));
}

return $class;
}
}