<?php

declare(strict_types=1);

namespace PhpSchool\PhpWorkshop;

use Closure;

use PhpSchool\PhpWorkshop\Patch\Transformer;

/**

* This class is responsible for storing the modifications that should

* be made to a PHP file. That includes insertions and transformers.

* A transformer is a simple closure which should receives an AST

* representation of the student's solution and it should return the modified AST.

*

* Transformers can also be class implementing `Transformer`.

*

* An insertion is a block of code that can be inserted at the top or bottom of

* the students solution.

*/

final class Patch

{

/**

* @var array<CodeInsertion|Closure|Transformer>

*/

private $modifications = [];

/**

* Add a new `CodeInsertion`. `Patch` is immutable so a new instance is returned.

*

* @param CodeInsertion $insertion

* @return self

*/

public function withInsertion(CodeInsertion $insertion): self

{

$new = clone $this;

$new->modifications[] = $insertion;

return $new;

}

/**

* Add a new transformer (`Closure` OR `Transformer`). `Patch` is immutable so a new instance is returned.

*

* @param Closure|Transformer $closure

* @return self

*/

public function withTransformer($closure): self

{

$new = clone $this;

$new->modifications[] = $closure;

return $new;

}

/**

* Retrieve all the modifications including insertions (`CodeInsertion`'s)

* & transformers (`Closure`'s OR `Transformer`'s)

*

* @return array<CodeInsertion|Closure|Transformer>

*/

public function getModifiers(): array

{

return $this->modifications;

}

}