<?php

namespace App\Libraries;

use Dompdf\Dompdf;
use Dompdf\Options;

/**
 * Renders Vidal Health Corporate Analysis MIS HTML to PDF via DomPDF.
 */
class VidalMisPdfService
{
    /**
     * @param array<string,mixed> $report
     * @return array{status:bool,message?:string,content?:string,filename?:string}
     */
    public function generateFromReport(array $report, int $policyId): array
    {
        $vm       = $report['view_model'] ?? $report;
        $policyNo = trim((string) ($report['header']['policy_number'] ?? (string) $policyId));

        $html = view('claims_mis_vidal', [
            'report'     => $report,
            'view_model' => $vm,
            'policy_id'  => $policyId,
            'pdf_url'    => '',
            'embed'      => true,
        ]);

        return $this->generate($html, $policyNo);
    }

    /**
     * @return array{status:bool,message?:string,content?:string,filename?:string}
     */
    public function generate(string $html, string $policyNo): array
    {
        $safePolicy = preg_replace('/[^A-Za-z0-9_\-]+/', '_', $policyNo) ?: 'policy';
        $filename   = 'VIDAL_MIS_' . $safePolicy . '_' . date('Ymd') . '.pdf';

        try {
            $options = new Options();
            $options->set('isHtml5ParserEnabled', true);
            $options->set('isRemoteEnabled', true);
            $options->set('isFontSubsettingEnabled', true);
            $options->set('defaultFont', 'DejaVu Sans');
            $options->setChroot([
                rtrim(ROOTPATH, '/\\'),
                rtrim(FCPATH, '/\\'),
                rtrim(WRITEPATH, '/\\'),
                sys_get_temp_dir(),
            ]);

            $dompdf = new Dompdf($options);
            $dompdf->loadHtml($this->prepareHtml($html));
            $dompdf->setPaper('A4', 'portrait');
            $dompdf->render();

            $content = $dompdf->output();
            if ($content === '' || $content === null) {
                return ['status' => false, 'message' => 'PDF generation failed: empty output.'];
            }

            return [
                'status'   => true,
                'content'  => $content,
                'filename' => $filename,
            ];
        } catch (\Throwable $e) {
            log_message('error', 'VidalMisPdfService::generate failed | ' . $e->getMessage());

            return ['status' => false, 'message' => 'PDF generation failed: ' . $e->getMessage()];
        }
    }

    private function prepareHtml(string $html): string
    {
        $html = preg_replace('#<script\b[^>]*>.*?</script>#is', '', $html) ?? $html;
        $html = preg_replace('/[\x{1F300}-\x{1FAFF}]/u', '', $html) ?? $html;

        $vars = [
            'var(--blue)'         => '#0072bc',
            'var(--header-blue)'  => '#dbe9f5',
            'var(--group-header)' => '#b9d6ec',
            'var(--border)'       => '#888',
            'var(--text)'         => '#111',
            'var(--muted)'        => '#444',
            'var(--male)'         => '#4472c4',
            'var(--female)'       => '#ed7d31',
        ];
        $html = str_replace(array_keys($vars), array_values($vars), $html);
        $html = preg_replace('#:root\s*\{[^}]*\}#is', '', $html) ?? $html;

        $html = preg_replace_callback(
            '#(<img\b[^>]*\bsrc=["\'])([^"\']+)(["\'][^>]*>)#i',
            function (array $m): string {
                $src     = html_entity_decode($m[2], ENT_QUOTES);
                $dataUri = $this->toDataUri($src);

                return $m[1] . ($dataUri ?: $src) . $m[3];
            },
            $html
        ) ?? $html;

        return $html;
    }

    private function toDataUri(string $path): ?string
    {
        $path = trim($path);
        if ($path === '' || str_starts_with($path, 'data:')) {
            return null;
        }

        if (preg_match('#^file://#i', $path)) {
            $path = preg_replace('#^file://#i', '', $path) ?? $path;
        }

        if (!is_file($path) || !is_readable($path)) {
            return null;
        }

        $ext  = strtolower(pathinfo($path, PATHINFO_EXTENSION));
        $mime = match ($ext) {
            'png'         => 'image/png',
            'jpg', 'jpeg' => 'image/jpeg',
            'gif'         => 'image/gif',
            'webp'        => 'image/webp',
            default       => 'application/octet-stream',
        };

        $bytes = @file_get_contents($path);
        if ($bytes === false || $bytes === '') {
            return null;
        }

        return 'data:' . $mime . ';base64,' . base64_encode($bytes);
    }
}