<?php

namespace JMS\Serializer\Util;

use JMS\Serializer\Exception\RuntimeException;

/**
* A writer implementation.
*
* This may be used to simplify writing well-formatted code.
*
* @author Johannes M. Schmitt <schmittjoh@gmail.com>
*/
class Writer
{
public $indentationSpaces = 4;
public $indentationLevel = 0;
public $content = '';
public $changeCount = 0;

private $changes = array();

public function indent()
{
$this->indentationLevel += 1;

return $this;
}

public function outdent()
{
$this->indentationLevel -= 1;

if ($this->indentationLevel < 0) {
throw new RuntimeException('The identation level cannot be less than zero.');
}

return $this;
}

/**
* @param string $content
*
* @return Writer
*/
public function writeln($content)
{
$this->write($content . "\n");

return $this;
}

public function revert()
{
$change = array_pop($this->changes);
$this->changeCount -= 1;
$this->content = substr($this->content, 0, -1 * \strlen($change));
}

/**
* @param string $content
*
* @return Writer
*/
public function write($content)
{
$addition = '';

$lines = explode("\n", $content);
for ($i = 0, $c = \count($lines); $i < $c; $i++) {
if ($this->indentationLevel > 0
&& !empty($lines[$i])
&& ((empty($addition) && "\n" === substr($this->content, -1)) || "\n" === substr($addition, -1))
) {
$addition .= str_repeat(' ', $this->indentationLevel * $this->indentationSpaces);
}

$addition .= $lines[$i];

if ($i + 1 < $c) {
$addition .= "\n";
}
}

$this->content .= $addition;
$this->changes[] = $addition;
$this->changeCount += 1;

return $this;
}

public function rtrim($preserveNewLines = true)
{
if (!$preserveNewLines) {
$this->content = rtrim($this->content);

return $this;
}

$addNl = "\n" === substr($this->content, -1);
$this->content = rtrim($this->content);

if ($addNl) {
$this->content .= "\n";
}

return $this;
}

public function reset()
{
$this->content = '';
$this->indentationLevel = 0;

return $this;
}

public function getContent()
{
return $this->content;
}
}