?php
namespace ForminatorAdminPDF\PDF;

use Mpdf\Mpdf;
use Mpdf\MpdfException;
use Mpdf\HTMLParserMode;
use Forminator_Form_Model;

defined('ABSPATH') || exit;

class Generator {

    public static function generate(array $mapped, int $form_id) {

        if (empty($mapped)) {
            fap_log("FAP: Generator::generate() - No data provided");
            return false;
        }

        /* ---------- load layout ---------- */
        $layout = require FAP_PATH . 'pdf-templates/layout.php';

        $embedded_pdfs = [];
        $image_vars = [];
        $sealed_uploads = [];

        $form = Forminator_Form_Model::model()->load($form_id);

        $title = 'Form Submission';

        if ($form && !empty($form->settings['formName'])) {
            $title = $form->settings['formName'];
        }

        $metadata = [
            'generated' => current_time('mysql'),
            'form_id'   => $form_id,
            'form_name' => $title,
        ];

        $full_data = [
            'metadata' => $metadata,
            'fields'   => $mapped,
        ];

        /* ---------- base HTML ---------- */
        $html  = '<base href="">';
        $html .= $layout['header']($title);
        $html .= $layout['base_css']();

        /* ---------- fields ---------- */
        foreach ($mapped as $key => $field) {

            $field_id = 'field_' . $key;

            /* ---------- HTML fields ---------- */
            if ($field['type'] === 'html') {

                // Invisible start/end markers
                $start_marker_html = '<div style="font-size:0.1px; line-height:0.1px; color:#000; position:absolute;">[FAP_FIELD_' . $field_id . ']</div>';
                $end_marker_html   = '<div style="font-size:0.1px; line-height:0.1px; color:#000; position:absolute;">[FAP_FIELD_END]</div>';

                if (!empty($field['label'])) {
                    $html .= $layout['field'](
                        $field['label'],
                        $start_marker_html . $field['value'] . $end_marker_html
                    );
                } else {
                    $html .= '<div class="field-block">' . $start_marker_html . $field['value'] . $end_marker_html . '</div>';
                }

                continue;
            }

            if (!isset($field['label'], $field['value'])) {
                continue;
            }

            $cell_html = esc_html($field['value']);

            /* ---------- uploads & signatures ---------- */
            if (
                in_array($field['type'], ['upload', 'signature'], true)
                && !empty($field['materialized_files'])
                && is_array($field['materialized_files'])
            ) {

                foreach ($field['materialized_files'] as $file) {

                    $mime = $file['mime'] ?? '';
                    $name = $file['name'] ?? 'file';

                    /* ---------- embedded PDF ---------- */
                    if ($mime === 'application/pdf' && !empty($file['base64'])) {

                        $embed_dir = self::get_embed_storage_dir();
                        $safe_name = preg_replace('/[^a-zA-Z0-9._-]/', '_', $name);
                        $temp_path = $embed_dir . '/' . uniqid('embed_', true) . '_' . $safe_name;

                        $binary = base64_decode($file['base64'], true);
                        if ($binary === false) continue;

                        $file_hash = hash('sha256', $binary);

                        if (file_put_contents($temp_path, $binary) === false) {
                            fap_log("FAP: ERROR: Could not write embed file " . basename($temp_path));
                            continue;
                        }

                        /* ---- seal upload ---- */
                        $sealed_uploads[] = [
                            'name'          => $safe_name,
                            'mime'          => 'application/pdf',
                            'sha256'        => $file_hash,
                            'hash_input'    => '',
                        ];

                        $embedded_pdfs[$safe_name] = [
                            'path'           => $temp_path,
                            'name'           => $safe_name,
                            'mime'           => 'application/pdf',
                            'description'    => 'Hochgeladenes Dokument',
                            'AFRelationship' => 'Supplement',
                        ];

                        continue;
                    }

                    /* ---------- images ---------- */
                    if (str_starts_with($mime, 'image/') && !empty($file['base64'])) {

                        $binary = base64_decode($file['base64'], true);
                        if ($binary === false) continue;

                        $width = $height = 0;
                        $colorspace = 'DeviceRGB'; // default

                        // Get image dimensions
                        $info = getimagesizefromstring($binary);
                        if ($info) {
                            $width  = $info[0];
                            $height = $info[1];

                            // Determine colorspace (simplified)
                            $channels = $info['channels'] ?? 3; // 'channels' is available for PNG/JPEG
                            if ($channels === 1) {
                                $colorspace = 'DeviceGray';
                            } elseif ($channels === 3) {
                                $colorspace = 'DeviceRGB';
                            } elseif ($channels === 4) {
                                $colorspace = 'DeviceCMYK';
                            }
                        }

                        // JPEG survives PDF round-trip as raw DCT bytes → use content hash.
                        // PNG is decoded to raw pixels inside the PDF XObject, so the byte
                        // representation changes; fall back to the dimension fingerprint which
                        // is stable across the encode/decode cycle.
                        $is_jpeg = in_array($mime, ['image/jpeg', 'image/jpg'], true);
                        if ($is_jpeg) {
                            $img_hash   = hash('sha256', $binary);
                            $hash_input = ''; // empty sentinel = content hash
                        } else {
                            $img_hash   = hash('sha256', $colorspace . '|' . $width . '|' . $height);
                            $hash_input = $colorspace . '|' . $width . '|' . $height;
                        }

                        /* ---- seal upload ---- */
                        $sealed_uploads[] = [
                            'name'       => (string) $name,
                            'mime'       => (string) $mime,
                            'sha256'     => $img_hash,
                            'hash_input' => $hash_input,
                        ];

                        $image_var = 'img_' . uniqid();
                        $image_vars[$image_var] = $binary;

                        $cell_html .= $layout['image']($image_var);
                    }
                }
            }

            // Wrap field value with invisible markers for PDF text extraction
            $start_marker_html = '<div style="font-size:0.1px; line-height:0.1px; color:#000; position:absolute;">[FAP_FIELD_' . $field_id . ']</div>';
            $end_marker_html   = '<div style="font-size:0.1px; line-height:0.1px; color:#000; position:absolute;">[FAP_FIELD_END]</div>';
            $cell_html         = $start_marker_html . $cell_html . $end_marker_html;

            $html .= $layout['field']($field['label'], $cell_html);
        }

        /* ---------- Add Metadata HTML ---------- */
        $html .= $layout['document_metadata']($full_data);

        $template = [];

        $logo_path = FAP_PATH . 'pdf-templates/logo.png';
        $line_path = FAP_PATH . 'pdf-templates/line.png';
        $grid_svg  = FAP_PATH . 'pdf-templates/construction-grid.svg';

        foreach ([$logo_path, $line_path, $grid_svg] as $path) {
            if (!file_exists($path) || !is_readable($path)) {
                error_log("Template file missing: {$path}");
                continue;
            }

            $data = file_get_contents($path);
            $mime = mime_content_type($path) ?: 'application/octet-stream';

            $width = $height = 0;
            $colorspace = 'DeviceRGB'; // fallback

            if (in_array($mime, ['image/png','image/jpeg'], true)) {
                $info = getimagesizefromstring($data);
                if ($info) {
                    $width  = $info[0];
                    $height = $info[1];

                    // Determine colorspace properly
                    if ($mime === 'image/png') {
                        // read IHDR color type
                        $colorType = ord($data[25]); // IHDR: 25th byte in PNG
                        switch ($colorType) {
                            case 0: $colorspace = 'DeviceGray'; break;
                            case 2: $colorspace = 'DeviceRGB'; break;
                            case 3: $colorspace = 'IndexedRGB'; break;
                            case 4: $colorspace = 'DeviceGray'; break; // grayscale + alpha
                            case 6: $colorspace = 'DeviceRGB'; break; // RGB + alpha
                            default: $colorspace = 'DeviceRGB';
                        }
                    } else { // JPEG
                        $colorspace = ($info['channels'] ?? 3) === 1 ? 'DeviceGray' : 'DeviceRGB';
                    }
                }
            }

            // --- Per-image fingerprint matching verifier ---
            $img_id = hash('sha256', $colorspace . '|' . $width . '|' . $height);

            $template[] = [
                'name'       => basename($path),
                'mime'       => $mime,
                'sha256'     => $img_id,
                'hash_input' => $colorspace . '|' . $width . '|' . $height,
            ];
        }

        /* ---------- PDF generation (2-pass with font sniffing) ---------- */
        try {

            $upload_dir = wp_upload_dir();
            $safe_dir   = $upload_dir['basedir'] . '/forminator-secure-pdf';

            // Ensure directories exist with restricted permissions.
            foreach (['', '/pdf', '/embed', '/mpdf'] as $sub) {
                $dir = $safe_dir . $sub;
                if (!is_dir($dir)) {
                    wp_mkdir_p($dir);
                    chmod($dir, 0750);
                    file_put_contents($dir . '/index.php', "");
                    chmod($dir . '/index.php', 0640);
                }
            }

            // Block all direct HTTP access to the secure-pdf tree.
            $htaccess = $safe_dir . '/.htaccess';
            if (!file_exists($htaccess)) {
                file_put_contents(
                    $htaccess,
                    "Options -Indexes\nDeny from all\n"
                );
                chmod($htaccess, 0640);
            }

            $pdf_dir   = $safe_dir . '/pdf';   // final PDFs
            $embed_dir = $safe_dir . '/embed'; // embedded PDFs
            $mpdf_temp = $safe_dir . '/mpdf';  // mPDF temp files

            $form_name_clean = preg_replace('/[^a-zA-Z0-9_-]/', '_', $metadata['form_name']);
            $date_time = wp_date('D_d_m_Y_T_H_i');

            /* ============================================================
            * PASS 1 — Generate PDF WITHOUT seal (font discovery)
            * ============================================================ */

            $mpdf = new Mpdf([
                'tempDir' => $mpdf_temp,
            ]);

            // Background
            $grid_svg = FAP_PATH . 'pdf-templates/construction-grid.svg';
            $mpdf->SetDefaultBodyCSS('background', "url('{$grid_svg}')");
            $mpdf->SetDefaultBodyCSS('background-repeat', 'repeat');
            $mpdf->SetDefaultBodyCSS('background-position', 'center center');

            // Footer
            $mpdf->SetHTMLFooter(
                '<div style="text-align:right;font-size:10pt;">
                    <span style="font-size:0.1px; line-height:0.1px; color:#fff;">
                        [FAP_PAGENO_START]
                    </span>
                    Seite {PAGENO} von {nbpg}
                    <span style="font-size:0.1px; line-height:0.1px; color:#fff;">
                        [FAP_PAGENO_END]
                    </span>
                </div>'
            );

            // Images
            if (!empty($image_vars)) {
                $mpdf->imageVars = $image_vars;
            }

            // Write main HTML ONLY
            self::write_html_chunked($mpdf, $html, 1500000);

            // Output temporary PDF
            $sl_file_name = "SL_{$form_name_clean}_{$date_time}.pdf";
            $sl_file_path = $mpdf_temp . '/' . $sl_file_name;

            $mpdf->Output($sl_file_path, \Mpdf\Output\Destination::FILE);
            unset($mpdf);

            /* ============================================================
            * Extract fonts from temporary PDF
            * ============================================================ */

            $fonts = [];
            $expected_pages = 0;
            $pdf_raw = file_get_contents($sl_file_path);

            if ($pdf_raw !== false) {
                if (preg_match_all('/\/BaseFont\s*\/([A-Za-z0-9\+\-_]+)/', $pdf_raw, $matches)) {
                    foreach ($matches[1] as $font) {
                        // Strip subset prefix (e.g. MPDFAA+)
                        $font = preg_replace('/^[A-Z]{6}\+/', '', $font);
                        $fonts[$font] = true;
                    }
                }
                preg_match_all('/\/Type\s*\/Page\b/', $pdf_raw, $page_matches);
                $expected_pages = count($page_matches[0]);
            }

            $fonts = array_keys($fonts);

            // Remove temporary SL PDF
            if (!unlink($sl_file_path)) {
                error_log("FAP: WARNING: Could not delete temp SL PDF: " . basename($sl_file_path));
            }

            /* ============================================================
            * PASS 2 — Generate FINAL PDF WITH seal
            * ============================================================ */

            $mpdf = new Mpdf([
                'tempDir' => $mpdf_temp,
            ]);

            // Re-apply same setup
            $mpdf->SetDefaultBodyCSS('background', "url('{$grid_svg}')");
            $mpdf->SetDefaultBodyCSS('background-repeat', 'repeat');
            $mpdf->SetDefaultBodyCSS('background-position', 'center center');

            $mpdf->SetHTMLFooter(
                '<div style="text-align:right;font-size:10pt;">
                    <span style="font-size:0.1px; line-height:0.1px; color:#fff;">
                        [FAP_PAGENO_START]
                    </span>
                    Seite {PAGENO} von {nbpg}
                    <span style="font-size:0.1px; line-height:0.1px; color:#fff;">
                        [FAP_PAGENO_END]
                    </span>
                </div>'
            );

            if (!empty($image_vars)) {
                $mpdf->imageVars = $image_vars;
            }

            // Write main HTML again
            self::write_html_chunked($mpdf, $html, 1500000);

            // Build seal with REAL fonts
            $seal_data = [
                'generated'      => trim((string)$metadata['generated']),
                'form_id'        => (int)$metadata['form_id'],
                'form_name'      => self::normalize_field_value($metadata['form_name']),
                'fields'         => self::build_seal_fields($mapped),
                'uploads'        => $sealed_uploads,
                'template'       => $template,
                'fonts'          => $fonts,
                'expected_pages' => $expected_pages,
            ];

            $hash = HashSeal::generate($seal_data);
            $seal_data['seal'] = $hash;

            $seal_json   = json_encode($seal_data, JSON_UNESCAPED_SLASHES);
            $seal_base64 = base64_encode($seal_json);

            $seal_html = '<div style="font-size:0.1px; line-height:0.1px; color:#000; position:absolute; bottom:0; left:0;">
            ---BEGIN-SEAL---
            ' . $seal_base64 . '
            ---END-SEAL---
            </div>';

            self::write_html_chunked($mpdf, $seal_html, 1500000);

            // Final output
            $final_file_name = "Entry_{$form_name_clean}_{$date_time}.pdf";
            $final_file_path = $pdf_dir . '/' . $final_file_name;

            $mpdf->Output($final_file_path, \Mpdf\Output\Destination::FILE);

            // Cleanup embedded PDFs
            foreach ($embedded_pdfs as $pdf) {
                if (!empty($pdf['path']) && file_exists($pdf['path'])) {
                    @unlink($pdf['path']);
                }
            }

            return $final_file_path;

        } catch (MpdfException $e) {
            error_log("FAP: PDF generation error: " . $e->getMessage() . " in " . basename($e->getFile()) . ":" . $e->getLine());
            return false;
        }
    }

    private static function get_embed_storage_dir(): string {
        $upload_dir = wp_upload_dir();
        $dir = $upload_dir['basedir'] . '/forminator-secure-pdf/embed';

        if (!is_dir($dir)) {
            wp_mkdir_p($dir);
            file_put_contents($dir . '/index.php', "");
        }

        return $dir;
    }

    private static function write_html_chunked(Mpdf $mpdf, string $html, int $chunkSize = 800000): void {

        // Normalize line endings
        $html = str_replace(["\r\n", "\r"], "\n", $html);

        // Split on ANY closing tag (much more aggressive)
        $parts = preg_split(
            '/(<\/[^>]+>)/i',
            $html,
            -1,
            PREG_SPLIT_DELIM_CAPTURE
        );

        $buffer = '';
        $first  = true;
        $chunk  = 0;

        foreach ($parts as $part) {
            $buffer .= $part;

            // HARD limit: force flush if buffer is too large
            if (strlen($buffer) >= $chunkSize) {
                $chunk++;

                $mpdf->WriteHTML(
                    $buffer,
                    $first ? HTMLParserMode::DEFAULT_MODE : HTMLParserMode::HTML_BODY
                );

                $buffer = '';
                $first  = false;
            }
        }

        if ($buffer !== '') {
            $chunk++;

            $mpdf->WriteHTML(
                $buffer,
                $first ? HTMLParserMode::DEFAULT_MODE : HTMLParserMode::HTML_BODY
            );
        }
    }

    private static function build_seal_fields(array $mapped): array {
        $fields = [];

        foreach ($mapped as $field) {
            $entry = [
                'label' => (string) ($field['label'] ?? ''),
                'value' => '',
            ];

            // Normalize field value
            if (!empty($field['value']) && is_string($field['value'])) {
                $entry['value'] = self::normalize_field_value($field['value']);
            }

            $fields[] = $entry;
        }

        return $fields;
    }

    private static function normalize_field_value(string $value): string {
        // Decode HTML entities
        $value = html_entity_decode($value, ENT_QUOTES | ENT_HTML5, 'UTF-8');
        // Strip all HTML
        $value = wp_strip_all_tags($value);
        // Collapse whitespace
        $value = preg_replace('/\s+/u', ' ', $value);

        return trim($value);
    }
}
<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="https://dghk.makerundcode.de/wp-sitemap-index.xsl" ?>
<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"><sitemap><loc>https://dghk.makerundcode.de/wp-sitemap-posts-page-1.xml</loc></sitemap><sitemap><loc>https://dghk.makerundcode.de/wp-sitemap-posts-event-1.xml</loc></sitemap><sitemap><loc>https://dghk.makerundcode.de/wp-sitemap-posts-location-1.xml</loc></sitemap><sitemap><loc>https://dghk.makerundcode.de/wp-sitemap-taxonomies-event-tags-1.xml</loc></sitemap><sitemap><loc>https://dghk.makerundcode.de/wp-sitemap-taxonomies-event-categories-1.xml</loc></sitemap></sitemapindex>