<?php
/**
* Copyright © Magento, Inc. All rights reserved.
* See COPYING.txt for license details.
*/

namespace Magento\Framework\Code\Reader;

/**
* Class resolve short namespaces to fully qualified namespaces.
*/
class NamespaceResolver
{
/**
* Namespace separator
*/
const NS_SEPARATOR = '\\';

/**
* @var ScalarTypesProvider
*/
private $scalarTypesProvider;

/**
* @var array
*/
private $namespaces = [];

/**
* NamespaceResolver constructor.
* @param ScalarTypesProvider $scalarTypesProvider
*/
public function __construct(ScalarTypesProvider $scalarTypesProvider = null)
{
$this->scalarTypesProvider = $scalarTypesProvider ?: new ScalarTypesProvider();
}

/**
* Perform namespace resolution if required and return fully qualified name.
*
* @param string $type
* @param array $availableNamespaces
* @return string
*/
public function resolveNamespace($type, array $availableNamespaces)
{
if (substr($type, 0, 1) !== self::NS_SEPARATOR
&& !in_array($type, $this->scalarTypesProvider->getTypes())
&& !empty($type)
) {
$name = explode(self::NS_SEPARATOR, $type);
$unqualifiedName = $name[0];
$isQualifiedName = count($name) > 1;
if (isset($availableNamespaces[$unqualifiedName])) {
$namespace = $availableNamespaces[$unqualifiedName];
if ($isQualifiedName) {
array_shift($name);
return $namespace . self::NS_SEPARATOR . implode(self::NS_SEPARATOR, $name);
}
return $namespace;
} else {
return self::NS_SEPARATOR . $availableNamespaces[0] . self::NS_SEPARATOR . $type;
}
}
return $type;
}

/**
* Get all imported namespaces from provided class.
*
* @param array $fileContent
* @return array
* @SuppressWarnings(PHPMD.CyclomaticComplexity)
*/
public function getImportedNamespaces(array $fileContent)
{
$fileContent = implode('', $fileContent);

$cacheKey = sha1($fileContent);

if (isset($this->namespaces[$cacheKey])) {
return $this->namespaces[$cacheKey];
}

$fileContent = token_get_all($fileContent);
$classStart = array_search('{', $fileContent);
$fileContent = array_slice($fileContent, 0, $classStart);
$output = [];
foreach ($fileContent as $position => $token) {
if (is_array($token) && $token[0] === T_USE) {
$import = array_slice($fileContent, $position);
$importEnd = array_search(';', $import);
$import = array_slice($import, 0, $importEnd);
$imports = [];
$importsCount = 0;
foreach ($import as $item) {
if ($item === ',') {
$importsCount++;
continue;
}
$imports[$importsCount][] = $item;
}
foreach ($imports as $import) {
$import = array_filter(
$import,
function ($token) {
$whitelist = [T_NS_SEPARATOR, T_STRING, T_AS];
if (isset($token[0]) && in_array($token[0], $whitelist)) {
return true;
}
return false;
}
);
$import = array_map(
function ($element) {
return $element[1];
},
$import
);
$import = array_values($import);
if ($import[0] === self::NS_SEPARATOR) {
array_shift($import);
}
$importName = null;
if (in_array('as', $import)) {
$importName = array_splice($import, -1)[0];
array_pop($import);
}
$useStatement = implode('', $import);
if ($importName) {
$output[$importName] = self::NS_SEPARATOR . $useStatement;
} else {
$key = explode(self::NS_SEPARATOR, $useStatement);
$key = end($key);
$output[$key] = self::NS_SEPARATOR . $useStatement;
}
}
}
}
$this->namespaces[$cacheKey] = $output;
return $this->namespaces[$cacheKey];
}
}