<?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';

/**
 *  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)
    {
        // This is a placeholder - we'll need to implement actual PDF filling
        // For now, we'll create a simple PDF with the data
        
        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 = '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;
        }

        // Move uploaded file
        $target_path = $this->template_path . 'ca3_custom_template.pdf';
        if (!is_dir($this->template_path)) {
            dol_mkdir($this->template_path);
        }

        if (move_uploaded_file($file['tmp_name'], $target_path)) {
            return true;
        } else {
            $this->error = 'Failed to save template';
            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
    }
}