<?php declare(strict_types=1);
/*
 * This file is part of PHPUnit.
 *
 * (c) Sebastian Bergmann <sebastian@phpunit.de>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */
namespace PHPUnit\Runner\Phpt;

use const DIRECTORY_SEPARATOR;
use function assert;
use function dirname;
use function explode;
use function file;
use function file_get_contents;
use function is_file;
use function is_readable;
use function is_string;
use function preg_match;
use function rtrim;
use function str_contains;
use function trim;
use PHPUnit\Runner\Exception;

/**
 * @no-named-arguments Parameter names are not covered by the backward compatibility promise for PHPUnit
 *
 * @internal This class is not covered by the backward compatibility promise for PHPUnit
 *
 * @see https://qa.php.net/phpt_details.php
 */
final readonly class Parser
{
    /**
     * @param non-empty-string $phptFile
     *
     * @throws Exception
     *
     * @return array<non-empty-string, non-empty-string>
     */
    public function parse(string $phptFile): array
    {
        $sections = [];
        $section  = '';

        $unsupportedSections = [
            'CGI',
            'COOKIE',
            'DEFLATE_POST',
            'EXPECTHEADERS',
            'EXTENSIONS',
            'GET',
            'GZIP_POST',
            'HEADERS',
            'PHPDBG',
            'POST',
            'POST_RAW',
            'PUT',
            'REDIRECTTEST',
            'REQUEST',
        ];

        $lineNr = 0;

        foreach (file($phptFile) as $line) {
            $lineNr++;

            if (preg_match('/^--([_A-Z]+)--/', $line, $result)) {
                $section                        = $result[1];
                $sections[$section]             = '';
                $sections[$section . '_offset'] = $lineNr;

                continue;
            }

            if ($section === '') {
                throw new InvalidPhptFileException;
            }

            $sections[$section] .= $line;
        }

        if (isset($sections['FILEEOF'])) {
            $sections['FILE'] = rtrim($sections['FILEEOF'], "\r\n");

            unset($sections['FILEEOF']);
        }

        $this->parseExternal($phptFile, $sections);
        $this->validate($sections);

        foreach ($unsupportedSections as $unsupportedSection) {
            if (isset($sections[$unsupportedSection])) {
                throw new UnsupportedPhptSectionException($unsupportedSection);
            }
        }

        return $sections;
    }

    /**
     * @return array<non-empty-string, non-empty-string>
     */
    public function parseEnvSection(string $content): array
    {
        $env = [];

        foreach (explode("\n", trim($content)) as $e) {
            $e = explode('=', trim($e), 2);

            if ($e[0] !== '' && isset($e[1])) {
                $env[$e[0]] = $e[1];
            }
        }

        return $env;
    }

    /**
     * @param array<string>|string                                              $content
     * @param array<non-empty-string, array<non-empty-string>|non-empty-string> $ini
     *
     * @return array<non-empty-string, array<non-empty-string>|non-empty-string>
     */
    public function parseIniSection(array|string $content, array $ini = []): array
    {
        if (is_string($content)) {
            $content = explode("\n", trim($content));
        }

        foreach ($content as $setting) {
            if (!str_contains($setting, '=')) {
                continue;
            }

            $setting = explode('=', $setting, 2);
            $name    = trim($setting[0]);
            $value   = trim($setting[1]);

            if ($name === 'extension' || $name === 'zend_extension') {
                if (!isset($ini[$name])) {
                    $ini[$name] = [];
                }

                $ini[$name][] = $value;

                continue;
            }

            $ini[$name] = $value;
        }

        return $ini;
    }

    /**
     * @param non-empty-string                          $phptFile
     * @param array<non-empty-string, non-empty-string> $sections
     *
     * @throws Exception
     */
    private function parseExternal(string $phptFile, array &$sections): void
    {
        $allowSections = [
            'FILE',
            'EXPECT',
            'EXPECTF',
            'EXPECTREGEX',
        ];

        $testDirectory = dirname($phptFile) . DIRECTORY_SEPARATOR;

        foreach ($allowSections as $section) {
            if (isset($sections[$section . '_EXTERNAL'])) {
                $externalFilename = trim($sections[$section . '_EXTERNAL']);

                if (!is_file($testDirectory . $externalFilename) ||
                    !is_readable($testDirectory . $externalFilename)) {
                    throw new PhptExternalFileCannotBeLoadedException(
                        $section,
                        $testDirectory . $externalFilename,
                    );
                }

                $contents = file_get_contents($testDirectory . $externalFilename);

                assert($contents !== false && $contents !== '');

                $sections[$section] = $contents;
            }
        }
    }

    /**
     * @param array<non-empty-string, non-empty-string> $sections
     *
     * @throws InvalidPhptFileException
     */
    private function validate(array $sections): void
    {
        if (!isset($sections['FILE'])) {
            throw new InvalidPhptFileException;
        }

        if (!isset($sections['EXPECT']) &&
            !isset($sections['EXPECTF']) &&
            !isset($sections['EXPECTREGEX'])) {
            throw new InvalidPhptFileException;
        }
    }
}