<?php
/* Copyright (C) 2025		Frank Cools
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <https://www.gnu.org/licenses/>.
 */

/**
 * 	\file       core/class/declarationtva_pdf.class.php
 *  \ingroup    declarationtva
 *  \brief      PDF generation for CA-3 declarations
 */

require_once DOL_DOCUMENT_ROOT.'/core/lib/pdf.lib.php';
require_once DOL_DOCUMENT_ROOT.'/core/lib/company.lib.php';
require_once DOL_DOCUMENT_ROOT.'/core/lib/date.lib.php';

// Load TCPDF for PDF support (Dolibarr's standard)
require_once DOL_DOCUMENT_ROOT.'/includes/tecnickcom/tcpdf/tcpdf.php';

// Load FPDI-TCPDF for fillable PDF support
require_once DOL_DOCUMENT_ROOT.'/custom/declarationtva/vendor/autoload.php';

/**
 *  Class to generate CA-3 declaration PDF
 */
class DeclarationTVA_PDF
{
    /**
     * @var DoliDB Database handler
     */
    public $db;

    /**
     * @var string Error code (or message)
     */
    public $error = '';

    /**
     * @var string[] Several error codes (or messages)
     */
    public $errors = array();

    /**
     * @var int Entity
     */
    public $entity;

    /**
     * @var string Template path
     */
    public $template_path;

    /**
     * @var string Template version
     */
    public $template_version = '30';

    /**
     * @var string Template document number
     */
    public $template_document = '10963';

    /**
     * @var string Gitea repository URL for templates
     */
    public $gitea_repo_url = 'https://git.covago.com/frank/DeclarationTVA';

    /**
     * @var string Manifest file URL
     */
    public $manifest_url = 'https://git.covago.com/frank/DeclarationTVA/raw/branch/main/templates/manifest.json';


    /**
     * Constructor
     *
     * @param DoliDB $db Database handler
     */
    public function __construct($db)
    {
        $this->db = $db;
        $this->entity = (int) $conf->entity;
        $this->template_path = DOL_DOCUMENT_ROOT.'/custom/declarationtva/templates/declarationtva/';
    }

    /**
     * Generate CA-3 declaration PDF
     *
     * @param int $declaration_id Declaration ID
     * @param string $outputlangs Output language
     * @return string|false PDF file path or false on error
     */
    public function generateCA3PDF($declaration_id, $outputlangs = '')
    {
        global $conf, $langs, $user;

        // Load declaration data
        $declaration = new DeclarationTVA($this->db);
        $result = $declaration->fetch($declaration_id);
        if ($result <= 0) {
            $this->error = 'Declaration not found';
            return false;
        }

        // Get CA-3 line data
        $ca3_data = $declaration->getCA3Lines($declaration_id);
        if (empty($ca3_data)) {
            $this->error = 'No CA-3 data found';
            return false;
        }

        // Get company information
        $company = new Societe($this->db);
        $company->fetch($conf->entity);

        // Generate PDF filename
        $filename = 'CA3_' . $declaration->declaration_number . '_' . date('Y-m-d') . '.pdf';
        $filepath = DOL_DATA_ROOT . '/declarationtva/' . $filename;

        // Ensure directory exists
        if (!is_dir(DOL_DATA_ROOT . '/declarationtva/')) {
            dol_mkdir(DOL_DATA_ROOT . '/declarationtva/');
        }

        // Check if we have a custom template
        $template_file = $this->getTemplatePath();
        if (!$template_file) {
            $this->error = 'CA-3 template not found';
            return false;
        }

        // Generate PDF using FPDI or similar library
        $result = $this->fillPDFTemplate($template_file, $filepath, $declaration, $ca3_data, $company);
        
        if ($result) {
            return $filepath;
        } else {
            return false;
        }
    }

    /**
     * Get the template file path (custom or default)
     *
     * @return string|false Template file path or false if not found
     */
    private function getTemplatePath()
    {
        // Check for custom template first
        $custom_template = $this->template_path . 'ca3_custom_template.pdf';
        if (file_exists($custom_template)) {
            return $custom_template;
        }

        // Fall back to default template
        $default_template = $this->template_path . 'ca3_official_template.pdf';
        if (file_exists($default_template)) {
            return $default_template;
        }

        return false;
    }

    /**
     * Fill PDF template with declaration data
     *
     * @param string $template_path Template file path
     * @param string $output_path Output file path
     * @param DeclarationTVA $declaration Declaration object
     * @param array $ca3_data CA-3 line data
     * @param Societe $company Company object
     * @return bool Success
     */
    private function fillPDFTemplate($template_path, $output_path, $declaration, $ca3_data, $company)
    {
        try {
            // Check if we have a custom fillable PDF template
            if (file_exists($template_path) && $this->isFillablePDF($template_path)) {
                return $this->fillFillablePDF($template_path, $output_path, $declaration, $ca3_data, $company);
            } else {
                // Fall back to basic PDF generation
                return $this->generateBasicPDF($output_path, $declaration, $ca3_data, $company);
            }
        } catch (Exception $e) {
            $this->error = 'PDF generation failed: ' . $e->getMessage();
            return false;
        }
    }

    /**
     * Check if PDF is fillable (has form fields)
     *
     * @param string $pdf_path PDF file path
     * @return bool True if fillable
     */
    private function isFillablePDF($pdf_path)
    {
        // Simple check - if it's our custom template, assume it's fillable
        return strpos($pdf_path, 'ca3_custom_template.pdf') !== false;
    }

    /**
     * Fill a fillable PDF template using pdftk
     *
     * @param string $template_path Template file path
     * @param string $output_path Output file path
     * @param DeclarationTVA $declaration Declaration object
     * @param array $ca3_data CA-3 line data
     * @param Societe $company Company object
     * @return bool Success
     */
    private function fillFillablePDF($template_path, $output_path, $declaration, $ca3_data, $company)
    {
        try {
            // Check if pdftk is available
            if (!$this->isPdftkAvailable()) {
                // Fallback to manual approach if pdftk is not available
                return $this->fillFillablePDFManual($template_path, $output_path, $declaration, $ca3_data, $company);
            }
            
            // Prepare field data mapping
            $field_data = $this->prepareFieldData($declaration, $ca3_data, $company);
            
            // Create FDF data file for pdftk
            $fdf_file = $this->createFDFFile($field_data, $declaration);
            
            // Use pdftk to fill the form
            $pdftk_path = $this->getPdftkPath();
            $command = "\"$pdftk_path\" \"$template_path\" fill_form \"$fdf_file\" output \"$output_path\"";
            $result = shell_exec($command . ' 2>&1');
            
            // Clean up temporary FDF file
            if (file_exists($fdf_file)) {
                unlink($fdf_file);
            }
            
            // Check if output file was created successfully
            if (file_exists($output_path) && filesize($output_path) > 0) {
                return true;
            } else {
                $this->error = 'pdftk failed to generate output: ' . $result;
                return false;
            }
            
        } catch (Exception $e) {
            $this->error = 'Failed to fill PDF template: ' . $e->getMessage();
            return false;
        }
    }

    /**
     * Prepare field data for PDF form filling
     *
     * @param DeclarationTVA $declaration Declaration object
     * @param array $ca3_data CA-3 line data
     * @param Societe $company Company object
     * @return array Field data mapping
     */
    private function prepareFieldData($declaration, $ca3_data, $company)
    {
        $field_data = array();
        
        // Get the actual company information from Dolibarr configuration
        global $conf, $mysoc;
        
        // Use Dolibarr's company configuration
        $field_data['company_name'] = $mysoc->name;
        $field_data['company_address'] = $mysoc->address;
        $field_data['company_city'] = $mysoc->town;
        $field_data['company_postal_code'] = $mysoc->zip;
        
        // Debug: Log company information to see what's available
        error_log("DeclarationTVA: Company data - name: " . $mysoc->name);
        error_log("DeclarationTVA: Company data - idprof1: " . $mysoc->idprof1);
        error_log("DeclarationTVA: Company data - idprof2: " . $mysoc->idprof2);
        error_log("DeclarationTVA: Company data - idprof3: " . $mysoc->idprof3);
        error_log("DeclarationTVA: Company data - idprof4: " . $mysoc->idprof4);
        error_log("DeclarationTVA: Company data - tva_intra: " . $mysoc->tva_intra);
        
        // Try different fields for SIRET - it could be in different idprof fields
        $siret_value = !empty($mysoc->idprof2) ? $mysoc->idprof2 : 
                       (!empty($mysoc->idprof1) ? $mysoc->idprof1 : 
                       (!empty($mysoc->idprof3) ? $mysoc->idprof3 : 
                       (!empty($mysoc->idprof4) ? $mysoc->idprof4 : '')));
        
        // If no SIRET found, use a placeholder for testing
        if (empty($siret_value)) {
            $siret_value = 'SIRET_NOT_CONFIGURED';
            error_log("DeclarationTVA: No SIRET found in company configuration. Please configure SIRET in Dolibarr company settings.");
        }
        
        $field_data['company_siret'] = $this->formatSiret($siret_value);
        
        $field_data['company_vat_number'] = $mysoc->tva_intra; // VAT number
        $field_data['declaration_period_start'] = dol_print_date($declaration->start_date, 'day');
        $field_data['declaration_period_end'] = dol_print_date($declaration->end_date, 'day');
        $field_data['declaration_number'] = $declaration->declaration_number;
        
        // Section A: Opérations imposables
        $field_data['A1_amount'] = $this->getCA3LineAmount($ca3_data, 'A1');
        $field_data['A2_amount'] = $this->getCA3LineAmount($ca3_data, 'A2');
        $field_data['A3_amount'] = $this->getCA3LineAmount($ca3_data, 'A3');
        $field_data['A4_amount'] = $this->getCA3LineAmount($ca3_data, 'A4');
        $field_data['A5_amount'] = $this->getCA3LineAmount($ca3_data, 'A5');
        
        // Section A: Additional reference fields (E1-E6, F1-F2, F6-F8)
        $field_data['E1_amount'] = $this->getCA3LineAmount($ca3_data, 'E1');
        $field_data['E2_amount'] = $this->getCA3LineAmount($ca3_data, 'E2');
        $field_data['E3_amount'] = $this->getCA3LineAmount($ca3_data, 'E3');
        $field_data['E4_amount'] = $this->getCA3LineAmount($ca3_data, 'E4');
        $field_data['E5_amount'] = $this->getCA3LineAmount($ca3_data, 'E5');
        $field_data['E6_amount'] = $this->getCA3LineAmount($ca3_data, 'E6');
        $field_data['F1_amount'] = $this->getCA3LineAmount($ca3_data, 'F1');
        $field_data['F2_amount'] = $this->getCA3LineAmount($ca3_data, 'F2');
        $field_data['F6_amount'] = $this->getCA3LineAmount($ca3_data, 'F6');
        $field_data['F7_amount'] = $this->getCA3LineAmount($ca3_data, 'F7');
        $field_data['F8_amount'] = $this->getCA3LineAmount($ca3_data, 'F8');
        
        // Debug: Log the CA-3 data structure for troubleshooting
        if (empty($ca3_data)) {
            error_log("DeclarationTVA: CA-3 data is empty");
            // Use test data for debugging
            $ca3_data = array(
                'A1' => array('vat_amount' => 1000.00),
                'A2' => array('vat_amount' => 2000.00),
                '08' => array('base_amount' => 5000.00, 'vat_amount' => 1000.00),
                '09' => array('base_amount' => 10000.00, 'vat_amount' => 2000.00),
                '20' => array('vat_amount' => 500.00),
                'F1' => array('vat_amount' => 300.00),
                'F2' => array('vat_amount' => 400.00)
            );
            error_log("DeclarationTVA: Using test data for debugging");
        } else {
            error_log("DeclarationTVA: CA-3 data structure: " . print_r($ca3_data, true));
        }
        
        // Debug: Log specific amount field values
        error_log("DeclarationTVA: A1_amount will be: " . $this->getCA3LineAmount($ca3_data, 'A1'));
        error_log("DeclarationTVA: B08_vat_amount will be: " . $this->getCA3LineAmount($ca3_data, '08', 'vat_amount'));
        error_log("DeclarationTVA: B09_vat_amount will be: " . $this->getCA3LineAmount($ca3_data, '09', 'vat_amount'));
        error_log("DeclarationTVA: total_vat_collected will be: " . $this->formatAmount($declaration->total_vat_collected));
        
        // Section B: TVA due (Base + VAT columns)
        $field_data['B08_base_amount'] = $this->getCA3LineAmount($ca3_data, '08', 'base_amount');
        $field_data['B08_vat_amount'] = $this->getCA3LineAmount($ca3_data, '08', 'vat_amount');
        $field_data['B09_base_amount'] = $this->getCA3LineAmount($ca3_data, '09', 'base_amount');
        $field_data['B09_vat_amount'] = $this->getCA3LineAmount($ca3_data, '09', 'vat_amount');
        $field_data['B9B_base_amount'] = $this->getCA3LineAmount($ca3_data, '9B', 'base_amount');
        $field_data['B9B_vat_amount'] = $this->getCA3LineAmount($ca3_data, '9B', 'vat_amount');
        $field_data['B17_amount'] = $this->getCA3LineAmount($ca3_data, '17');
        
        // Section C: TVA déductible
        $field_data['C20_amount'] = $this->getCA3LineAmount($ca3_data, '20');
        $field_data['C21_amount'] = $this->getCA3LineAmount($ca3_data, '21');
        $field_data['C22_amount'] = $this->getCA3LineAmount($ca3_data, '22');
        
        // Section F: Intracom Acquisitions (already mapped above in Section A)
        
        // Section D: Résultat (Calculated)
        $field_data['D25_amount'] = $this->getCA3LineAmount($ca3_data, '25');
        $field_data['D26_amount'] = $this->getCA3LineAmount($ca3_data, '26');
        $field_data['DTD_amount'] = $this->getCA3LineAmount($ca3_data, 'TD');
        $field_data['D28_amount'] = $this->getCA3LineAmount($ca3_data, '28');
        $field_data['D29_amount'] = $this->getCA3LineAmount($ca3_data, '29');
        
        // Subtotals
        $field_data['subtotal_B16_amount'] = $this->getCA3LineAmount($ca3_data, '16');
        $field_data['subtotal_C23_amount'] = $this->getCA3LineAmount($ca3_data, '23');
        
        // Grand totals
        $field_data['total_vat_collected'] = $this->formatAmount($declaration->total_vat_collected);
        $field_data['total_vat_deductible'] = $this->formatAmount($declaration->total_vat_deductible);
        $field_data['net_vat_due'] = $this->formatAmount($declaration->net_vat_due);
        $field_data['vat_credit'] = $this->formatAmount($declaration->vat_credit);
        
        return $field_data;
    }
    
    /**
     * Format amount for PDF display
     *
     * @param float $amount Amount to format
     * @return string Formatted amount
     */
    private function formatAmount($amount)
    {
        return number_format($amount, 0, ',', ' ');
    }
    
    /**
     * Fill a PDF form field by modifying PDF content
     *
     * @param string $pdf_content PDF content
     * @param string $field_name Field name
     * @param string $value Field value
     * @return string Modified PDF content
     */
    private function fillPDFFormField($pdf_content, $field_name, $value)
    {
        // Escape special characters in the value
        $escaped_value = $this->escapePDFString($value);
        
        // Look for the field in the PDF content and replace its value
        // This is a simplified approach that works for many PDF types
        
        // Pattern 1: Look for /T(field_name) and add /V(value) after it
        $pattern1 = '/\/T\s*\(\s*' . preg_quote($field_name, '/') . '\s*\)/';
        if (preg_match($pattern1, $pdf_content)) {
            $pdf_content = preg_replace(
                $pattern1,
                '/T(' . $field_name . ') /V(' . $escaped_value . ')',
                $pdf_content
            );
        }
        
        // Pattern 2: Look for existing /V values and replace them
        $pattern2 = '/\/T\s*\(\s*' . preg_quote($field_name, '/') . '\s*\).*?\/V\s*\([^)]*\)/';
        if (preg_match($pattern2, $pdf_content)) {
            $pdf_content = preg_replace(
                $pattern2,
                '/T(' . $field_name . ') /V(' . $escaped_value . ')',
                $pdf_content
            );
        }
        
        return $pdf_content;
    }
    
    /**
     * Check if pdftk is available on the system
     *
     * @return bool True if pdftk is available
     */
    private function isPdftkAvailable()
    {
        // Try multiple common locations for pdftk
        $possible_paths = array(
            '/usr/bin/pdftk',
            '/usr/local/bin/pdftk',
            '/bin/pdftk',
            '/opt/pdftk/bin/pdftk',
            '/usr/share/pdftk/bin/pdftk',
            '/home/*/bin/pdftk',
            '/home/*/.local/bin/pdftk'
        );
        
        foreach ($possible_paths as $path) {
            if (strpos($path, '*') !== false) {
                // Handle glob patterns
                $glob_paths = glob($path);
                foreach ($glob_paths as $glob_path) {
                    if (file_exists($glob_path) && is_executable($glob_path)) {
                        $test_result = shell_exec("$glob_path --version 2>&1");
                        if (!empty($test_result) && strpos($test_result, 'pdftk') !== false) {
                            return true;
                        }
                    }
                }
            } else {
                if (file_exists($path) && is_executable($path)) {
                    $test_result = shell_exec("$path --version 2>&1");
                    if (!empty($test_result) && strpos($test_result, 'pdftk') !== false) {
                        return true;
                    }
                }
            }
        }
        
        // Fallback: try 'which pdftk' in case it's in PATH
        $result = shell_exec('which pdftk 2>/dev/null');
        if (!empty(trim($result))) {
            $test_result = shell_exec(trim($result) . ' --version 2>&1');
            if (!empty($test_result) && strpos($test_result, 'pdftk') !== false) {
                return true;
            }
        }
        
        return false;
    }
    
    /**
     * Get the full path to pdftk executable
     *
     * @return string Path to pdftk executable
     */
    private function getPdftkPath()
    {
        // Try multiple common locations for pdftk
        $possible_paths = array(
            '/usr/bin/pdftk',
            '/usr/local/bin/pdftk',
            '/bin/pdftk',
            '/opt/pdftk/bin/pdftk',
            '/usr/share/pdftk/bin/pdftk',
            '/home/*/bin/pdftk',
            '/home/*/.local/bin/pdftk'
        );
        
        foreach ($possible_paths as $path) {
            if (strpos($path, '*') !== false) {
                // Handle glob patterns
                $glob_paths = glob($path);
                foreach ($glob_paths as $glob_path) {
                    if (file_exists($glob_path) && is_executable($glob_path)) {
                        $test_result = shell_exec("$glob_path --version 2>&1");
                        if (!empty($test_result) && strpos($test_result, 'pdftk') !== false) {
                            return $glob_path;
                        }
                    }
                }
            } else {
                if (file_exists($path) && is_executable($path)) {
                    $test_result = shell_exec("$path --version 2>&1");
                    if (!empty($test_result) && strpos($test_result, 'pdftk') !== false) {
                        return $path;
                    }
                }
            }
        }
        
        // Fallback: try 'which pdftk' in case it's in PATH
        $result = shell_exec('which pdftk 2>/dev/null');
        if (!empty(trim($result))) {
            $test_result = shell_exec(trim($result) . ' --version 2>&1');
            if (!empty($test_result) && strpos($test_result, 'pdftk') !== false) {
                return trim($result);
            }
        }
        
        // Default fallback
        return 'pdftk';
    }
    
    /**
     * Create FDF file for pdftk form filling
     *
     * @param array $field_data Field data
     * @param DeclarationTVA $declaration Declaration object
     * @return string FDF file path
     */
    private function createFDFFile($field_data, $declaration)
    {
        $fdf_file = sys_get_temp_dir() . '/ca3_fdf_' . $declaration->declaration_number . '_' . uniqid() . '.fdf';
        
        $fdf_content = "%FDF-1.2\n";
        $fdf_content .= "1 0 obj\n";
        $fdf_content .= "<<\n";
        $fdf_content .= "/FDF\n";
        $fdf_content .= "<<\n";
        $fdf_content .= "/Fields [\n";
        
        foreach ($field_data as $field_name => $value) {
            if (!empty($value)) {
                $fdf_content .= "<<\n";
                $fdf_content .= "/T (" . $field_name . ")\n";
                $fdf_content .= "/V (" . $this->escapeFDFString($value) . ")\n";
                
                // Force Courier New 9pt for official documents
                $fdf_content .= "/Ff 0\n"; // Field flags (0 = no special flags)
                $fdf_content .= "/F 9\n";  // Font size 9pt
                $fdf_content .= "/DA (/Cour 9 Tf 0 g)\n"; // Courier 9pt, black
                $fdf_content .= "/Q 0\n";  // Left alignment
                $fdf_content .= ">>\n";
            }
        }
        
        $fdf_content .= "]\n";
        $fdf_content .= ">>\n";
        $fdf_content .= ">>\n";
        $fdf_content .= "endobj\n";
        $fdf_content .= "trailer\n";
        $fdf_content .= "<<\n";
        $fdf_content .= "/Root 1 0 R\n";
        $fdf_content .= ">>\n";
        $fdf_content .= "%%EOF\n";
        
        file_put_contents($fdf_file, $fdf_content);
        return $fdf_file;
    }
    
    /**
     * Escape string for FDF format
     *
     * @param string $value Value to escape
     * @return string Escaped value
     */
    private function escapeFDFString($value)
    {
        // Escape special FDF characters
        $value = str_replace('\\', '\\\\', $value);
        $value = str_replace('(', '\\(', $value);
        $value = str_replace(')', '\\)', $value);
        return $value;
    }
    
    
    /**
     * Manual PDF filling fallback (when pdftk is not available)
     *
     * @param string $template_path Template file path
     * @param string $output_path Output file path
     * @param DeclarationTVA $declaration Declaration object
     * @param array $ca3_data CA-3 line data
     * @param Societe $company Company object
     * @return bool Success
     */
    private function fillFillablePDFManual($template_path, $output_path, $declaration, $ca3_data, $company)
    {
        try {
            // Simple approach: Just copy the template and create a data file
            if (copy($template_path, $output_path)) {
                // Create a data file with all the values for manual filling
                $data_file = dirname($output_path) . '/ca3_data_' . $declaration->declaration_number . '.txt';
                $field_data = $this->prepareFieldData($declaration, $ca3_data, $company);
                
                $data_content = "CA-3 Declaration Data (Manual Filling Required)\n";
                $data_content .= "============================================\n\n";
                $data_content .= "Note: pdftk is not installed. Please install pdftk for automatic form filling.\n";
                $data_content .= "See installation guide: /custom/declarationtva/docs/PDFTK_INSTALLATION.md\n\n";
                
                $data_content .= "Declaration: " . $declaration->declaration_number . "\n";
                $data_content .= "Period: " . dol_print_date($declaration->start_date, 'day') . " - " . dol_print_date($declaration->end_date, 'day') . "\n\n";
                
                $data_content .= "Company Information:\n";
                $data_content .= "-------------------\n";
                $data_content .= "company_name: " . $field_data['company_name'] . "\n";
                $data_content .= "company_address: " . $field_data['company_address'] . "\n";
                $data_content .= "company_city: " . $field_data['company_city'] . "\n";
                $data_content .= "company_postal_code: " . $field_data['company_postal_code'] . "\n";
                $data_content .= "company_siret: " . $field_data['company_siret'] . "\n\n";
                
                $data_content .= "Declaration Information:\n";
                $data_content .= "------------------------\n";
                $data_content .= "declaration_period_start: " . $field_data['declaration_period_start'] . "\n";
                $data_content .= "declaration_period_end: " . $field_data['declaration_period_end'] . "\n";
                $data_content .= "declaration_number: " . $field_data['declaration_number'] . "\n\n";
                
                $data_content .= "Section A - Opérations imposables:\n";
                $data_content .= "----------------------------------\n";
                $data_content .= "A1_amount: " . $field_data['A1_amount'] . "\n";
                $data_content .= "A2_amount: " . $field_data['A2_amount'] . "\n";
                $data_content .= "A3_amount: " . $field_data['A3_amount'] . "\n";
                $data_content .= "A4_amount: " . $field_data['A4_amount'] . "\n";
                $data_content .= "A5_amount: " . $field_data['A5_amount'] . "\n";
                $data_content .= "E1_amount: " . $field_data['E1_amount'] . "\n";
                $data_content .= "E2_amount: " . $field_data['E2_amount'] . "\n";
                $data_content .= "E3_amount: " . $field_data['E3_amount'] . "\n";
                $data_content .= "E4_amount: " . $field_data['E4_amount'] . "\n";
                $data_content .= "E5_amount: " . $field_data['E5_amount'] . "\n";
                $data_content .= "E6_amount: " . $field_data['E6_amount'] . "\n";
                $data_content .= "F1_amount: " . $field_data['F1_amount'] . "\n";
                $data_content .= "F2_amount: " . $field_data['F2_amount'] . "\n";
                $data_content .= "F6_amount: " . $field_data['F6_amount'] . "\n";
                $data_content .= "F7_amount: " . $field_data['F7_amount'] . "\n";
                $data_content .= "F8_amount: " . $field_data['F8_amount'] . "\n\n";
                
                $data_content .= "Section B - TVA due:\n";
                $data_content .= "--------------------\n";
                $data_content .= "B08_base_amount: " . $field_data['B08_base_amount'] . "\n";
                $data_content .= "B08_vat_amount: " . $field_data['B08_vat_amount'] . "\n";
                $data_content .= "B09_base_amount: " . $field_data['B09_base_amount'] . "\n";
                $data_content .= "B09_vat_amount: " . $field_data['B09_vat_amount'] . "\n";
                $data_content .= "B9B_base_amount: " . $field_data['B9B_base_amount'] . "\n";
                $data_content .= "B9B_vat_amount: " . $field_data['B9B_vat_amount'] . "\n";
                $data_content .= "B17_amount: " . $field_data['B17_amount'] . "\n\n";
                
                $data_content .= "Section C - TVA déductible:\n";
                $data_content .= "----------------------------\n";
                $data_content .= "C20_amount: " . $field_data['C20_amount'] . "\n";
                $data_content .= "C21_amount: " . $field_data['C21_amount'] . "\n";
                $data_content .= "C22_amount: " . $field_data['C22_amount'] . "\n\n";
                
                $data_content .= "Section D - Résultat:\n";
                $data_content .= "---------------------\n";
                $data_content .= "D25_amount: " . $field_data['D25_amount'] . "\n";
                $data_content .= "D26_amount: " . $field_data['D26_amount'] . "\n";
                $data_content .= "DTD_amount: " . $field_data['DTD_amount'] . "\n";
                $data_content .= "D28_amount: " . $field_data['D28_amount'] . "\n";
                $data_content .= "D29_amount: " . $field_data['D29_amount'] . "\n\n";
                
                $data_content .= "Totals:\n";
                $data_content .= "-------\n";
                $data_content .= "total_vat_collected: " . $field_data['total_vat_collected'] . "\n";
                $data_content .= "total_vat_deductible: " . $field_data['total_vat_deductible'] . "\n";
                $data_content .= "net_vat_due: " . $field_data['net_vat_due'] . "\n";
                $data_content .= "vat_credit: " . $field_data['vat_credit'] . "\n";
                
                file_put_contents($data_file, $data_content);
                
                return true;
            } else {
                $this->error = 'Failed to copy template file';
                return false;
            }
            
        } catch (Exception $e) {
            $this->error = 'Failed to fill PDF template: ' . $e->getMessage();
            return false;
        }
    }
    

    /**
     * Generate basic PDF (fallback method)
     *
     * @param string $output_path Output file path
     * @param DeclarationTVA $declaration Declaration object
     * @param array $ca3_data CA-3 line data
     * @param Societe $company Company object
     * @return bool Success
     */
    private function generateBasicPDF($output_path, $declaration, $ca3_data, $company)
    {
        try {
            // Create a new PDF document
            $pdf = new TCPDF(PDF_PAGE_ORIENTATION, PDF_UNIT, PDF_PAGE_FORMAT, true, 'UTF-8', false);
            
            // Set document information
            $pdf->SetCreator('DeclarationTVA Module');
            $pdf->SetAuthor($company->name);
            $pdf->SetTitle('CA-3 Declaration ' . $declaration->declaration_number);
            $pdf->SetSubject('French VAT Declaration');
            
            // Set margins
            $pdf->SetMargins(15, 15, 15);
            $pdf->SetHeaderMargin(5);
            $pdf->SetFooterMargin(10);
            
            // Add a page
            $pdf->AddPage();
            
            // Add title
            $pdf->SetFont('helvetica', 'B', 16);
            $pdf->Cell(0, 10, 'Déclaration TVA CA-3', 0, 1, 'C');
            $pdf->Ln(10);
            
            // Add declaration information
            $pdf->SetFont('helvetica', '', 12);
            $pdf->Cell(0, 8, 'Numéro de déclaration: ' . $declaration->declaration_number, 0, 1);
            $pdf->Cell(0, 8, 'Période: ' . dol_print_date($declaration->start_date, 'day') . ' - ' . dol_print_date($declaration->end_date, 'day'), 0, 1);
            $pdf->Cell(0, 8, 'Statut: ' . $declaration->status, 0, 1);
            $pdf->Ln(10);
            
            // Add CA-3 sections
            $this->addCA3Section($pdf, 'A. Opérations imposables', $ca3_data, array('A1', 'A2', 'A3', 'A4', 'A5'));
            $this->addCA3Section($pdf, 'B. TVA due', $ca3_data, array('08', '09', '9B', '17'));
            $this->addCA3Section($pdf, 'C. TVA déductible', $ca3_data, array('20', '21', '22'));
            $this->addCA3Section($pdf, 'D. Résultat', $ca3_data, array('25', '26', 'TD', '28', '29'));
            
            // Add totals
            $pdf->Ln(10);
            $pdf->SetFont('helvetica', 'B', 12);
            $pdf->Cell(0, 8, 'TOTAL TVA COLLECTÉE: ' . price($declaration->total_vat_collected, 0, '', 1, 0), 0, 1);
            $pdf->Cell(0, 8, 'TOTAL TVA DÉDUCTIBLE: ' . price($declaration->total_vat_deductible, 0, '', 1, 0), 0, 1);
            $pdf->Cell(0, 8, 'TVA NETTE DUE: ' . price($declaration->net_vat_due, 0, '', 1, 0), 0, 1);
            
            if ($declaration->vat_credit > 0) {
                $pdf->Cell(0, 8, 'CRÉDIT DE TVA: ' . price($declaration->vat_credit, 0, '', 1, 0), 0, 1);
            }
            
            // Output PDF
            $pdf->Output($output_path, 'F');
            
            return true;
            
        } catch (Exception $e) {
            $this->error = 'Basic PDF generation failed: ' . $e->getMessage();
            return false;
        }
    }

    /**
     * Add CA-3 section to PDF
     *
     * @param TCPDF $pdf PDF object
     * @param string $section_title Section title
     * @param array $ca3_data CA-3 data
     * @param array $lines Lines to include
     */
    private function addCA3Section($pdf, $section_title, $ca3_data, $lines)
    {
        $pdf->SetFont('helvetica', 'B', 12);
        $pdf->Cell(0, 8, $section_title, 0, 1);
        
        $pdf->SetFont('helvetica', '', 10);
        foreach ($lines as $line) {
            if (isset($ca3_data[$line])) {
                $data = $ca3_data[$line];
                $amount = isset($data['vat_amount']) ? $data['vat_amount'] : 0;
                $pdf->Cell(20, 6, $line, 1, 0, 'C');
                $pdf->Cell(100, 6, $data['line_label'], 1, 0);
                $pdf->Cell(30, 6, price($amount, 0, '', 1, 0), 1, 1, 'R');
            }
        }
        $pdf->Ln(5);
    }

    /**
     * Upload custom template
     *
     * @param array $file Uploaded file array
     * @return bool Success
     */
    public function uploadCustomTemplate($file)
    {
        if (!isset($file['tmp_name']) || !is_uploaded_file($file['tmp_name'])) {
            $this->error = 'No file uploaded';
            return false;
        }

        // Validate file type
        $file_info = pathinfo($file['name']);
        if (strtolower($file_info['extension']) !== 'pdf') {
            $this->error = 'Only PDF files are allowed';
            return false;
        }

        // Validate file size (max 10MB)
        if ($file['size'] > 10 * 1024 * 1024) {
            $this->error = 'File too large (max 10MB)';
            return false;
        }

        // Ensure template directory exists
        if (!is_dir($this->template_path)) {
            if (!dol_mkdir($this->template_path)) {
                $this->error = 'Failed to create template directory';
                return false;
            }
        }

        // Check directory permissions
        if (!is_writable($this->template_path)) {
            $this->error = 'Template directory is not writable';
            return false;
        }

        // Move uploaded file
        $target_path = $this->template_path . 'ca3_custom_template.pdf';
        
        // Remove existing custom template if it exists
        if (file_exists($target_path)) {
            unlink($target_path);
        }

        if (move_uploaded_file($file['tmp_name'], $target_path)) {
            // Verify the file was saved correctly
            if (file_exists($target_path) && filesize($target_path) > 0) {
                return true;
            } else {
                $this->error = 'Template file was not saved correctly';
                return false;
            }
        } else {
            $last_error = error_get_last();
            $this->error = 'Failed to save template: ' . ($last_error ? $last_error['message'] : 'Unknown error');
            return false;
        }
    }

    /**
     * Get template information
     *
     * @return array Template information
     */
    public function getTemplateInfo()
    {
        $info = array(
            'version' => $this->template_version,
            'document' => $this->template_document,
            'official_number' => $this->template_document . '*' . $this->template_version,
            'custom_template' => false,
            'template_path' => ''
        );

        $custom_template = $this->template_path . 'ca3_custom_template.pdf';
        if (file_exists($custom_template)) {
            $info['custom_template'] = true;
            $info['template_path'] = $custom_template;
        }

        return $info;
    }

    /**
     * Reset to default template
     *
     * @return bool Success
     */
    public function resetToDefaultTemplate()
    {
        $custom_template = $this->template_path . 'ca3_custom_template.pdf';
        if (file_exists($custom_template)) {
            return unlink($custom_template);
        }
        return true;
    }

    /**
     * Check for template updates from Gitea
     *
     * @return array Update information
     */
    public function checkTemplateUpdates()
    {
        $update_info = array(
            'update_available' => false,
            'current_version' => $this->template_version,
            'latest_version' => $this->template_version,
            'download_url' => '',
            'release_date' => '',
            'error' => ''
        );

        try {
            // Fetch manifest from Gitea
            $manifest_content = file_get_contents($this->manifest_url);
            if ($manifest_content === false) {
                $update_info['error'] = 'Failed to fetch manifest from Gitea';
                return $update_info;
            }

            $manifest = json_decode($manifest_content, true);
            if (!$manifest || !isset($manifest['templates']['ca3'])) {
                $update_info['error'] = 'Invalid manifest format';
                return $update_info;
            }

            $template_info = $manifest['templates']['ca3'];
            $latest_version = $template_info['current_version'];
            $current_version = $this->template_version;

            // Check if update is available
            if (version_compare($latest_version, $current_version, '>')) {
                $update_info['update_available'] = true;
                $update_info['latest_version'] = $latest_version;
                
                if (isset($template_info['releases'][$latest_version])) {
                    $release_info = $template_info['releases'][$latest_version];
                    $update_info['download_url'] = $release_info['download_url'];
                    $update_info['release_date'] = $release_info['release_date'];
                }
            }

        } catch (Exception $e) {
            $update_info['error'] = 'Error checking updates: ' . $e->getMessage();
        }

        return $update_info;
    }

    /**
     * Download and install template update
     *
     * @param string $version Version to download
     * @param string $download_url Download URL
     * @return bool Success
     */
    public function downloadTemplateUpdate($version, $download_url)
    {
        try {
            // Ensure template directory exists
            if (!is_dir($this->template_path)) {
                dol_mkdir($this->template_path);
            }

            // Download template
            $template_content = file_get_contents($download_url);
            if ($template_content === false) {
                $this->error = 'Failed to download template from Gitea';
                return false;
            }

            // Save as official template
            $template_file = $this->template_path . 'ca3_official_template.pdf';
            if (file_put_contents($template_file, $template_content) === false) {
                $this->error = 'Failed to save downloaded template';
                return false;
            }

            // Update version info
            $this->template_version = $version;

            return true;

        } catch (Exception $e) {
            $this->error = 'Error downloading template: ' . $e->getMessage();
            return false;
        }
    }

    /**
     * Get template update status
     *
     * @return array Status information
     */
    public function getTemplateUpdateStatus()
    {
        $status = array(
            'current_version' => $this->template_version,
            'update_available' => false,
            'latest_version' => $this->template_version,
            'last_check' => '',
            'error' => ''
        );

        // Check for updates
        $update_info = $this->checkTemplateUpdates();
        
        if ($update_info['update_available']) {
            $status['update_available'] = true;
            $status['latest_version'] = $update_info['latest_version'];
        }

        if (!empty($update_info['error'])) {
            $status['error'] = $update_info['error'];
        }

        // Store last check time
        $status['last_check'] = date('Y-m-d H:i:s');

        return $status;
    }

    /**
     * Auto-update template if available
     *
     * @return bool Success
     */
    public function autoUpdateTemplate()
    {
        $update_info = $this->checkTemplateUpdates();
        
        if ($update_info['update_available'] && !empty($update_info['download_url'])) {
            return $this->downloadTemplateUpdate(
                $update_info['latest_version'], 
                $update_info['download_url']
            );
        }

        return true; // No update needed
    }

    /**
     * Get CA-3 line amount from the data array
     *
     * @param array $ca3_data CA-3 data array
     * @param string $ca3_line Line identifier (e.g., 'A1', '08', '17')
     * @param string $amount_type Amount type ('vat_amount' or 'base_amount')
     * @return string Formatted amount
     */
    private function getCA3LineAmount($ca3_data, $ca3_line, $amount_type = 'vat_amount')
    {
        if (empty($ca3_data) || !is_array($ca3_data)) {
            return '0,00';
        }

        // Search through the array for the matching ca3_line
        foreach ($ca3_data as $line_data) {
            if (isset($line_data['ca3_line']) && $line_data['ca3_line'] == $ca3_line) {
                $amount = isset($line_data[$amount_type]) ? $line_data[$amount_type] : 0;
                return $this->formatAmount($amount);
            }
        }

        return '0,00';
    }

    /**
     * Format SIRET number with special spacing
     * Adds space between every character, with 3 extra spaces before last 5 characters
     *
     * @param string $siret SIRET number
     * @return string Formatted SIRET
     */
    private function formatSiret($siret)
    {
        // Remove any existing spaces or special characters
        $siret = preg_replace('/[^0-9]/', '', $siret);
        
        // If SIRET is not configured or too short, return as is
        if (empty($siret) || $siret === 'SIRET_NOT_CONFIGURED' || strlen($siret) < 5) {
            return $siret;
        }
        
        // Split into parts: main part and last 5 characters
        $main_part = substr($siret, 0, -5);
        $last_5 = substr($siret, -5);
        
        // Add space between every character in main part
        $formatted_main = implode(' ', str_split($main_part));
        
        // Add space between every character in last 5, with 3 extra spaces before
        $formatted_last = '   ' . implode(' ', str_split($last_5));
        
        return $formatted_main . $formatted_last;
    }
}