<?php

namespace Mindee\Parsing;

use Exception;
use Mindee\Error\ErrorCode;
use Mindee\Error\MindeeUnhandledException;

/**
 * Utility class to check the availability of potentially incompatible libraries.
 */
class DependencyChecker
{
    /**
     * Returns true if ghostscript is available on the system.
     *
     * @return void
     * @throws MindeeUnhandledException Throws if the GhostScript command cannot be found on the system.
     */
    public static function isGhostscriptAvailable(): void
    {
        try {
            if (strtoupper(substr(PHP_OS, 0, 3)) === 'WIN') {
                $possiblePaths = [
                    'C:\Program Files\gs\gs*\bin\gswin64c.exe',
                    'C:\Program Files (x86)\gs\gs*\bin\gswin32c.exe',
                    'C:\Program Files\gs\gs*\bin\gswin32c.exe'
                ];

                foreach ($possiblePaths as $path) {
                    $matches = glob($path);
                    if (!empty($matches)) {
                        $commandWasExecuted = true;
                    }
                }
                $pathDirs = explode(';', getenv('PATH'));
                foreach ($pathDirs as $dir) {
                    if (file_exists($dir . '\gswin64c.exe') || file_exists($dir . '\gswin32c.exe')) {
                        $commandWasExecuted = true;
                    }
                }
            } else {
                $commandWasExecuted = (bool)shell_exec('which gs');
            }
        } catch (Exception $e) {
            throw new MindeeUnhandledException(
                "To enable full support of PDF features, you need " .
                "to enable Ghostscript on your PHP installation.",
                ErrorCode::USER_MISSING_DEPENDENCY
            );
        }
        if (!$commandWasExecuted) {
            throw new MindeeUnhandledException(
                "To enable full support of PDF features, you need " .
                "to enable Ghostscript on your PHP installation.",
                ErrorCode::USER_MISSING_DEPENDENCY
            );
        }
    }

    /**
     * Returns true if ImageMagick is available on the system.
     *
     * @return void
     * @throws MindeeUnhandledException Throws if ImageMagick isn't loaded.
     */
    public static function isImageMagickAvailable(): void
    {
        if (!extension_loaded('imagick')) {
            throw new MindeeUnhandledException(
                "To enable full support of PDF features, you need " .
                "to enable ImageMagick on your PHP installation. Also, you " .
                "should setup ImageMagick's policy to allow for PDF operations.",
                ErrorCode::USER_MISSING_DEPENDENCY
            );
        }
    }

    /**
     * Checks whether Imagick is blocked by restrictive policy.
     *
     * @return void
     * @throws MindeeUnhandledException Throws if the local ImageMagick policy does not allow for PDF manipulations.
     */
    public static function isImageMagickPolicyAllowed(): void
    {
        self::isImageMagickAvailable();

        $imagick = new \Imagick();
        try {
            $imagick->readImage(
                (getenv('GITHUB_WORKSPACE') ?: ".") .
                "/tests/resources/products/expense_receipts/default_sample.jpg"
            );
        } catch (\Exception $e) {
            throw new MindeeUnhandledException(
                "To enable full support of PDF features, you need " .
                "to enable ImageMagick on your PHP installation. Also, you " .
                "should setup ImageMagick's policy to allow for PDF operations.",
                ErrorCode::USER_MISSING_DEPENDENCY
            );
        }
    }
}