<?php

declare(strict_types=1);

/*
 * This file is part of PHP CS Fixer.
 *
 * (c) Fabien Potencier <fabien@symfony.com>
 *     Dariusz Rumiński <dariusz.ruminski@gmail.com>
 *
 * This source file is subject to the MIT license that is bundled
 * with this source code in the file LICENSE.
 */

namespace PhpCsFixer\Fixer\PhpUnit;

use PhpCsFixer\AbstractFixer;
use PhpCsFixer\Fixer\ConfigurableFixerInterface;
use PhpCsFixer\FixerConfiguration\FixerConfigurationResolver;
use PhpCsFixer\FixerConfiguration\FixerConfigurationResolverInterface;
use PhpCsFixer\FixerConfiguration\FixerOptionBuilder;
use PhpCsFixer\FixerDefinition\CodeSample;
use PhpCsFixer\FixerDefinition\FixerDefinition;
use PhpCsFixer\FixerDefinition\FixerDefinitionInterface;
use PhpCsFixer\Preg;
use PhpCsFixer\Tokenizer\Analyzer\ClassyAnalyzer;
use PhpCsFixer\Tokenizer\Token;
use PhpCsFixer\Tokenizer\Tokens;

/**
 * @author Dariusz Rumiński <dariusz.ruminski@gmail.com>
 */
final class PhpUnitNamespacedFixer extends AbstractFixer implements ConfigurableFixerInterface
{
    /**
     * @var string
     */
    private $originalClassRegEx;

    /**
     * Class Mappings.
     *
     *  * [original classname => new classname] Some classes which match the
     *    original class regular expression do not have a same-compound name-
     *    space class and need a dedicated translation table. This trans-
     *    lation table is defined in @see configure.
     *
     * @var array<string, string> Class Mappings
     */
    private $classMap;

    public function getDefinition(): FixerDefinitionInterface
    {
        $codeSample = '<?php
final class MyTest extends \PHPUnit_Framework_TestCase
{
    public function testSomething()
    {
        PHPUnit_Framework_Assert::assertTrue(true);
    }
}
';

        return new FixerDefinition(
            'PHPUnit classes MUST be used in namespaced version, e.g. `\PHPUnit\Framework\TestCase` instead of `\PHPUnit_Framework_TestCase`.',
            [
                new CodeSample($codeSample),
                new CodeSample($codeSample, ['target' => PhpUnitTargetVersion::VERSION_4_8]),
            ],
            "PHPUnit v6 has finally fully switched to namespaces.\n"
            ."You could start preparing the upgrade by switching from non-namespaced TestCase to namespaced one.\n"
            .'Forward compatibility layer (`\PHPUnit\Framework\TestCase` class) was backported to PHPUnit v4.8.35 and PHPUnit v5.4.0.'."\n"
            .'Extended forward compatibility layer (`PHPUnit\Framework\Assert`, `PHPUnit\Framework\BaseTestListener`, `PHPUnit\Framework\TestListener` classes) was introduced in v5.7.0.'."\n",
            'Risky when PHPUnit classes are overridden or not accessible, or when project has PHPUnit incompatibilities.'
        );
    }

    public function isCandidate(Tokens $tokens): bool
    {
        return $tokens->isTokenKindFound(T_STRING);
    }

    public function isRisky(): bool
    {
        return true;
    }

    public function configure(array $configuration): void
    {
        parent::configure($configuration);

        if (PhpUnitTargetVersion::fulfills($this->configuration['target'], PhpUnitTargetVersion::VERSION_6_0)) {
            $this->originalClassRegEx = '/^PHPUnit_\w+$/i';
            // @noinspection ClassConstantCanBeUsedInspection
            $this->classMap = [
                'PHPUnit_Extensions_PhptTestCase' => 'PHPUnit\Runner\PhptTestCase',
                'PHPUnit_Framework_Constraint' => 'PHPUnit\Framework\Constraint\Constraint',
                'PHPUnit_Framework_Constraint_StringMatches' => 'PHPUnit\Framework\Constraint\StringMatchesFormatDescription',
                'PHPUnit_Framework_Constraint_JsonMatches_ErrorMessageProvider' => 'PHPUnit\Framework\Constraint\JsonMatchesErrorMessageProvider',
                'PHPUnit_Framework_Constraint_PCREMatch' => 'PHPUnit\Framework\Constraint\RegularExpression',
                'PHPUnit_Framework_Constraint_ExceptionMessageRegExp' => 'PHPUnit\Framework\Constraint\ExceptionMessageRegularExpression',
                'PHPUnit_Framework_Constraint_And' => 'PHPUnit\Framework\Constraint\LogicalAnd',
                'PHPUnit_Framework_Constraint_Or' => 'PHPUnit\Framework\Constraint\LogicalOr',
                'PHPUnit_Framework_Constraint_Not' => 'PHPUnit\Framework\Constraint\LogicalNot',
                'PHPUnit_Framework_Constraint_Xor' => 'PHPUnit\Framework\Constraint\LogicalXor',
                'PHPUnit_Framework_Error' => 'PHPUnit\Framework\Error\Error',
                'PHPUnit_Framework_TestSuite_DataProvider' => 'PHPUnit\Framework\DataProviderTestSuite',
                'PHPUnit_Framework_MockObject_Invocation_Static' => 'PHPUnit\Framework\MockObject\Invocation\StaticInvocation',
                'PHPUnit_Framework_MockObject_Invocation_Object' => 'PHPUnit\Framework\MockObject\Invocation\ObjectInvocation',
                'PHPUnit_Framework_MockObject_Stub_Return' => 'PHPUnit\Framework\MockObject\Stub\ReturnStub',
                'PHPUnit_Runner_Filter_Group_Exclude' => 'PHPUnit\Runner\Filter\ExcludeGroupFilterIterator',
                'PHPUnit_Runner_Filter_Group_Include' => 'PHPUnit\Runner\Filter\IncludeGroupFilterIterator',
                'PHPUnit_Runner_Filter_Test' => 'PHPUnit\Runner\Filter\NameFilterIterator',
                'PHPUnit_Util_PHP' => 'PHPUnit\Util\PHP\AbstractPhpProcess',
                'PHPUnit_Util_PHP_Default' => 'PHPUnit\Util\PHP\DefaultPhpProcess',
                'PHPUnit_Util_PHP_Windows' => 'PHPUnit\Util\PHP\WindowsPhpProcess',
                'PHPUnit_Util_Regex' => 'PHPUnit\Util\RegularExpression',
                'PHPUnit_Util_TestDox_ResultPrinter_XML' => 'PHPUnit\Util\TestDox\XmlResultPrinter',
                'PHPUnit_Util_TestDox_ResultPrinter_HTML' => 'PHPUnit\Util\TestDox\HtmlResultPrinter',
                'PHPUnit_Util_TestDox_ResultPrinter_Text' => 'PHPUnit\Util\TestDox\TextResultPrinter',
                'PHPUnit_Util_TestSuiteIterator' => 'PHPUnit\Framework\TestSuiteIterator',
                'PHPUnit_Util_XML' => 'PHPUnit\Util\Xml',
            ];
        } elseif (PhpUnitTargetVersion::fulfills($this->configuration['target'], PhpUnitTargetVersion::VERSION_5_7)) {
            $this->originalClassRegEx = '/^PHPUnit_Framework_(TestCase|Assert|BaseTestListener|TestListener)+$/i';
            $this->classMap = [];
        } else {
            $this->originalClassRegEx = '/^PHPUnit_Framework_TestCase$/i';
            $this->classMap = [];
        }
    }

    protected function applyFix(\SplFileInfo $file, Tokens $tokens): void
    {
        $importedOriginalClassesMap = [];
        $currIndex = 0;

        while (true) {
            $currIndex = $tokens->getNextTokenOfKind($currIndex, [[T_STRING]]);

            if (null === $currIndex) {
                break;
            }

            $prevIndex = $tokens->getPrevMeaningfulToken($currIndex);

            if ($tokens[$prevIndex]->isGivenKind([T_CONST, T_DOUBLE_COLON])) {
                continue;
            }

            $originalClass = $tokens[$currIndex]->getContent();
            $allowedReplacementScenarios = (new ClassyAnalyzer())->isClassyInvocation($tokens, $currIndex)
                || $this->isImport($tokens, $currIndex);

            if (!$allowedReplacementScenarios || !Preg::match($this->originalClassRegEx, $originalClass)) {
                ++$currIndex;

                continue;
            }

            $substituteTokens = $this->generateReplacement($originalClass);

            $tokens->clearAt($currIndex);
            $tokens->insertAt(
                $currIndex,
                isset($importedOriginalClassesMap[$originalClass]) ? $substituteTokens[$substituteTokens->getSize() - 1] : $substituteTokens
            );

            $prevIndex = $tokens->getPrevMeaningfulToken($currIndex);
            if ($tokens[$prevIndex]->isGivenKind(T_USE)) {
                $importedOriginalClassesMap[$originalClass] = true;
            } elseif ($tokens[$prevIndex]->isGivenKind(T_NS_SEPARATOR)) {
                $prevIndex = $tokens->getPrevMeaningfulToken($prevIndex);

                if ($tokens[$prevIndex]->isGivenKind(T_USE)) {
                    $importedOriginalClassesMap[$originalClass] = true;
                }
            }
        }
    }

    protected function createConfigurationDefinition(): FixerConfigurationResolverInterface
    {
        return new FixerConfigurationResolver([
            (new FixerOptionBuilder('target', 'Target version of PHPUnit.'))
                ->setAllowedTypes(['string'])
                ->setAllowedValues([PhpUnitTargetVersion::VERSION_4_8, PhpUnitTargetVersion::VERSION_5_7, PhpUnitTargetVersion::VERSION_6_0, PhpUnitTargetVersion::VERSION_NEWEST])
                ->setDefault(PhpUnitTargetVersion::VERSION_NEWEST)
                ->getOption(),
        ]);
    }

    private function generateReplacement(string $originalClassName): Tokens
    {
        $delimiter = '_';
        $string = $originalClassName;

        $map = array_change_key_case($this->classMap);
        if (isset($map[strtolower($originalClassName)])) {
            $delimiter = '\\';
            $string = $map[strtolower($originalClassName)];
        }

        $parts = explode($delimiter, $string);
        $tokensArray = [];

        while ([] !== $parts) {
            $tokensArray[] = new Token([T_STRING, array_shift($parts)]);
            if ([] !== $parts) {
                $tokensArray[] = new Token([T_NS_SEPARATOR, '\\']);
            }
        }

        return Tokens::fromArray($tokensArray);
    }

    private function isImport(Tokens $tokens, int $currIndex): bool
    {
        $prevIndex = $tokens->getPrevMeaningfulToken($currIndex);

        if ($tokens[$prevIndex]->isGivenKind([T_NS_SEPARATOR])) {
            $prevIndex = $tokens->getPrevMeaningfulToken($prevIndex);
        }

        return $tokens[$prevIndex]->isGivenKind([T_USE]);
    }
}