<?php
/**
 * Copyright seit 2024 Webshop System
 *
 * Admin-Newsletter-Controller für das Webshop-System
 *
 * @author    Webshop System
 * @license   GPL v3
 */

namespace App\Admin\Controllers;

use Doctrine\DBAL\DriverManager;
use Doctrine\DBAL\Exception;

class AdminNewsletterController
{
    public function index()
    {
        if (!isset($_SESSION['admin_id'])) {
            header('Location: /admin/login');
            exit;
        }
        
        $connectionParams = [
            'dbname' => getenv('DB_DATABASE') ?: 'freeshop',
            'user' => getenv('DB_USERNAME') ?: 'freeshop_user',
            'password' => getenv('DB_PASSWORD') ?: 'freeshop_password',
            'host' => getenv('DB_HOST') ?: 'db',
            'driver' => 'pdo_mysql',
            'port' => getenv('DB_PORT') ?: 3306,
            'charset' => 'utf8mb4',
        ];

        try {
            $conn = DriverManager::getConnection($connectionParams);
            
            // Newsletter-Abonnenten laden
            $stmt = $conn->prepare('
                SELECT n.*, c.first_name, c.last_name, c.email as customer_email
                FROM ws_newsletter n
                LEFT JOIN ws_customer c ON n.customer_id = c.id
                ORDER BY n.created_at DESC
            ');
            $stmt->execute();
            $subscribers = $stmt->fetchAllAssociative();
            
            // Newsletter-Templates laden
            $stmt = $conn->prepare('SELECT * FROM ws_newsletter_template ORDER BY created_at DESC');
            $stmt->execute();
            $templates = $stmt->fetchAllAssociative();
            
            // Statistiken
            $stmt = $conn->prepare('SELECT COUNT(*) as total FROM ws_newsletter WHERE active = 1');
            $stmt->execute();
            $activeSubscribers = $stmt->fetchAssociative()['total'];
            
            $stmt = $conn->prepare('SELECT COUNT(*) as total FROM ws_newsletter WHERE active = 0');
            $stmt->execute();
            $inactiveSubscribers = $stmt->fetchAssociative()['total'];
            
            $this->render('admin/newsletter/index.html.twig', [
                'title' => 'Webshop Admin - Newsletter-Verwaltung',
                'subscribers' => $subscribers,
                'templates' => $templates,
                'stats' => [
                    'active' => $activeSubscribers,
                    'inactive' => $inactiveSubscribers,
                    'total' => $activeSubscribers + $inactiveSubscribers
                ]
            ]);
            
        } catch (Exception $e) {
            $this->render('admin/newsletter/index.html.twig', [
                'title' => 'Webshop Admin - Newsletter-Verwaltung',
                'error' => 'Datenbankfehler: ' . $e->getMessage()
            ]);
        }
    }
    
    public function create()
    {
        if (!isset($_SESSION['admin_id'])) {
            header('Location: /admin/login');
            exit;
        }
        
        if ($_SERVER['REQUEST_METHOD'] === 'POST') {
            $this->processCreate();
        } else {
            $this->render('admin/newsletter/create.html.twig', [
                'title' => 'Webshop Admin - Newsletter erstellen'
            ]);
        }
    }
    
    private function processCreate()
    {
        $name = $_POST['name'] ?? '';
        $subject = $_POST['subject'] ?? '';
        $content = $_POST['content'] ?? '';
        $type = $_POST['type'] ?? 'newsletter';
        
        if (empty($name) || empty($subject) || empty($content)) {
            $this->render('admin/newsletter/create.html.twig', [
                'title' => 'Webshop Admin - Newsletter erstellen',
                'errors' => ['Alle Felder sind erforderlich'],
                'old' => $_POST
            ]);
            return;
        }
        
        $connectionParams = [
            'dbname' => getenv('DB_DATABASE') ?: 'freeshop',
            'user' => getenv('DB_USERNAME') ?: 'freeshop_user',
            'password' => getenv('DB_PASSWORD') ?: 'freeshop_password',
            'host' => getenv('DB_HOST') ?: 'db',
            'driver' => 'pdo_mysql',
            'port' => getenv('DB_PORT') ?: 3306,
            'charset' => 'utf8mb4',
        ];

        try {
            $conn = DriverManager::getConnection($connectionParams);
            
            $stmt = $conn->prepare('
                INSERT INTO ws_newsletter_template (name, subject, content, type, created_at)
                VALUES (?, ?, ?, ?, NOW())
            ');
            $stmt->execute([$name, $subject, $content, $type]);
            
            header('Location: /admin/newsletter?success=1');
            exit;
            
        } catch (Exception $e) {
            $this->render('admin/newsletter/create.html.twig', [
                'title' => 'Webshop Admin - Newsletter erstellen',
                'errors' => ['Fehler beim Erstellen: ' . $e->getMessage()],
                'old' => $_POST
            ]);
        }
    }
    
    public function edit($id)
    {
        if (!isset($_SESSION['admin_id'])) {
            header('Location: /admin/login');
            exit;
        }
        
        if ($_SERVER['REQUEST_METHOD'] === 'POST') {
            $this->processEdit($id);
        } else {
            $this->loadTemplate($id);
        }
    }
    
    private function loadTemplate($id)
    {
        $connectionParams = [
            'dbname' => getenv('DB_DATABASE') ?: 'freeshop',
            'user' => getenv('DB_USERNAME') ?: 'freeshop_user',
            'password' => getenv('DB_PASSWORD') ?: 'freeshop_password',
            'host' => getenv('DB_HOST') ?: 'db',
            'driver' => 'pdo_mysql',
            'port' => getenv('DB_PORT') ?: 3306,
            'charset' => 'utf8mb4',
        ];

        try {
            $conn = DriverManager::getConnection($connectionParams);
            
            $stmt = $conn->prepare('SELECT * FROM ws_newsletter_template WHERE id = ?');
            $stmt->execute([$id]);
            $template = $stmt->fetchAssociative();
            
            if (!$template) {
                header('Location: /admin/newsletter?error=Template nicht gefunden');
                exit;
            }
            
            $this->render('admin/newsletter/edit.html.twig', [
                'title' => 'Webshop Admin - Newsletter bearbeiten',
                'template' => $template
            ]);
            
        } catch (Exception $e) {
            header('Location: /admin/newsletter?error=' . urlencode($e->getMessage()));
            exit;
        }
    }
    
    private function processEdit($id)
    {
        $name = $_POST['name'] ?? '';
        $subject = $_POST['subject'] ?? '';
        $content = $_POST['content'] ?? '';
        $type = $_POST['type'] ?? 'newsletter';
        
        if (empty($name) || empty($subject) || empty($content)) {
            $this->render('admin/newsletter/edit.html.twig', [
                'title' => 'Webshop Admin - Newsletter bearbeiten',
                'errors' => ['Alle Felder sind erforderlich'],
                'template' => ['id' => $id] + $_POST
            ]);
            return;
        }
        
        $connectionParams = [
            'dbname' => getenv('DB_DATABASE') ?: 'freeshop',
            'user' => getenv('DB_USERNAME') ?: 'freeshop_user',
            'password' => getenv('DB_PASSWORD') ?: 'freeshop_password',
            'host' => getenv('DB_HOST') ?: 'db',
            'driver' => 'pdo_mysql',
            'port' => getenv('DB_PORT') ?: 3306,
            'charset' => 'utf8mb4',
        ];

        try {
            $conn = DriverManager::getConnection($connectionParams);
            
            $stmt = $conn->prepare('
                UPDATE ws_newsletter_template 
                SET name = ?, subject = ?, content = ?, type = ?, updated_at = NOW()
                WHERE id = ?
            ');
            $stmt->execute([$name, $subject, $content, $type, $id]);
            
            header('Location: /admin/newsletter?success=1');
            exit;
            
        } catch (Exception $e) {
            $this->render('admin/newsletter/edit.html.twig', [
                'title' => 'Webshop Admin - Newsletter bearbeiten',
                'errors' => ['Fehler beim Aktualisieren: ' . $e->getMessage()],
                'template' => ['id' => $id] + $_POST
            ]);
        }
    }
    
    public function delete($id)
    {
        if (!isset($_SESSION['admin_id'])) {
            header('Location: /admin/login');
            exit;
        }
        
        $connectionParams = [
            'dbname' => getenv('DB_DATABASE') ?: 'freeshop',
            'user' => getenv('DB_USERNAME') ?: 'freeshop_user',
            'password' => getenv('DB_PASSWORD') ?: 'freeshop_password',
            'host' => getenv('DB_HOST') ?: 'db',
            'driver' => 'pdo_mysql',
            'port' => getenv('DB_PORT') ?: 3306,
            'charset' => 'utf8mb4',
        ];

        try {
            $conn = DriverManager::getConnection($connectionParams);
            
            $stmt = $conn->prepare('DELETE FROM ws_newsletter_template WHERE id = ?');
            $stmt->execute([$id]);
            
            header('Location: /admin/newsletter?success=1');
            exit;
            
        } catch (Exception $e) {
            header('Location: /admin/newsletter?error=' . urlencode($e->getMessage()));
            exit;
        }
    }
    
    public function send($id)
    {
        if (!isset($_SESSION['admin_id'])) {
            header('Location: /admin/login');
            exit;
        }
        
        if ($_SERVER['REQUEST_METHOD'] === 'POST') {
            $this->processSend($id);
        } else {
            $this->loadSendForm($id);
        }
    }
    
    private function loadSendForm($id)
    {
        $connectionParams = [
            'dbname' => getenv('DB_DATABASE') ?: 'freeshop',
            'user' => getenv('DB_USERNAME') ?: 'freeshop_user',
            'password' => getenv('DB_PASSWORD') ?: 'freeshop_password',
            'host' => getenv('DB_HOST') ?: 'db',
            'driver' => 'pdo_mysql',
            'port' => getenv('DB_PORT') ?: 3306,
            'charset' => 'utf8mb4',
        ];

        try {
            $conn = DriverManager::getConnection($connectionParams);
            
            // Template laden
            $stmt = $conn->prepare('SELECT * FROM ws_newsletter_template WHERE id = ?');
            $stmt->execute([$id]);
            $template = $stmt->fetchAssociative();
            
            if (!$template) {
                header('Location: /admin/newsletter?error=Template nicht gefunden');
                exit;
            }
            
            // Abonnenten laden
            $stmt = $conn->prepare('SELECT * FROM ws_newsletter WHERE active = 1');
            $stmt->execute();
            $subscribers = $stmt->fetchAllAssociative();
            
            $this->render('admin/newsletter/send.html.twig', [
                'title' => 'Webshop Admin - Newsletter versenden',
                'template' => $template,
                'subscribers' => $subscribers
            ]);
            
        } catch (Exception $e) {
            header('Location: /admin/newsletter?error=' . urlencode($e->getMessage()));
            exit;
        }
    }
    
    private function processSend($id)
    {
        $templateId = $id;
        $testEmail = $_POST['test_email'] ?? '';
        $sendToAll = isset($_POST['send_to_all']);
        $selectedSubscribers = $_POST['subscribers'] ?? [];
        
        $connectionParams = [
            'dbname' => getenv('DB_DATABASE') ?: 'freeshop',
            'user' => getenv('DB_USERNAME') ?: 'freeshop_user',
            'password' => getenv('DB_PASSWORD') ?: 'freeshop_password',
            'host' => getenv('DB_HOST') ?: 'db',
            'driver' => 'pdo_mysql',
            'port' => getenv('DB_PORT') ?: 3306,
            'charset' => 'utf8mb4',
        ];

        try {
            $conn = DriverManager::getConnection($connectionParams);
            
            // Template laden
            $stmt = $conn->prepare('SELECT * FROM ws_newsletter_template WHERE id = ?');
            $stmt->execute([$templateId]);
            $template = $stmt->fetchAssociative();
            
            if (!$template) {
                throw new Exception('Template nicht gefunden');
            }
            
            $sentCount = 0;
            $errors = [];
            
            if (!empty($testEmail)) {
                // Test-E-Mail senden
                $this->sendNewsletterEmail($template, $testEmail, 'Test Kunde');
                $sentCount++;
            } elseif ($sendToAll) {
                // An alle Abonnenten senden
                $stmt = $conn->prepare('SELECT * FROM ws_newsletter WHERE active = 1');
                $stmt->execute();
                $subscribers = $stmt->fetchAllAssociative();
                
                foreach ($subscribers as $subscriber) {
                    try {
                        $this->sendNewsletterEmail($template, $subscriber['email'], $subscriber['first_name']);
                        $sentCount++;
                    } catch (Exception $e) {
                        $errors[] = 'Fehler bei ' . $subscriber['email'] . ': ' . $e->getMessage();
                    }
                }
            } elseif (!empty($selectedSubscribers)) {
                // An ausgewählte Abonnenten senden
                $placeholders = str_repeat('?,', count($selectedSubscribers) - 1) . '?';
                $stmt = $conn->prepare("SELECT * FROM ws_newsletter WHERE id IN ($placeholders) AND active = 1");
                $stmt->execute($selectedSubscribers);
                $subscribers = $stmt->fetchAllAssociative();
                
                foreach ($subscribers as $subscriber) {
                    try {
                        $this->sendNewsletterEmail($template, $subscriber['email'], $subscriber['first_name']);
                        $sentCount++;
                    } catch (Exception $e) {
                        $errors[] = 'Fehler bei ' . $subscriber['email'] . ': ' . $e->getMessage();
                    }
                }
            }
            
            // Newsletter-Log erstellen
            $stmt = $conn->prepare('
                INSERT INTO ws_newsletter_log (template_id, sent_count, error_count, created_at)
                VALUES (?, ?, ?, NOW())
            ');
            $stmt->execute([$templateId, $sentCount, count($errors)]);
            
            $message = "Newsletter erfolgreich versendet! $sentCount E-Mails gesendet.";
            if (!empty($errors)) {
                $message .= ' Fehler: ' . implode(', ', $errors);
            }
            
            header('Location: /admin/newsletter?success=' . urlencode($message));
            exit;
            
        } catch (Exception $e) {
            header('Location: /admin/newsletter?error=' . urlencode($e->getMessage()));
            exit;
        }
    }
    
    private function sendNewsletterEmail($template, $email, $firstName)
    {
        $subject = $template['subject'];
        $content = $template['content'];
        
        // Platzhalter ersetzen
        $content = str_replace('{{first_name}}', $firstName, $content);
        $content = str_replace('{{email}}', $email, $content);
        $content = str_replace('{{unsubscribe_url}}', '/newsletter/unsubscribe?token=' . bin2hex(random_bytes(16)), $content);
        
        $headers = 'MIME-Version: 1.0' . "\r\n";
        $headers .= 'Content-type: text/html; charset=UTF-8' . "\r\n";
        $headers .= 'From: Webshop <noreply@webshop-system.de>' . "\r\n";
        $headers .= 'Reply-To: info@webshop-system.de' . "\r\n";
        $headers .= 'X-Mailer: PHP/' . phpversion();
        
        if (!mail($email, $subject, $content, $headers)) {
            throw new Exception('E-Mail konnte nicht gesendet werden');
        }
    }
    
    public function subscribers()
    {
        if (!isset($_SESSION['admin_id'])) {
            header('Location: /admin/login');
            exit;
        }
        
        $connectionParams = [
            'dbname' => getenv('DB_DATABASE') ?: 'freeshop',
            'user' => getenv('DB_USERNAME') ?: 'freeshop_user',
            'password' => getenv('DB_PASSWORD') ?: 'freeshop_password',
            'host' => getenv('DB_HOST') ?: 'db',
            'driver' => 'pdo_mysql',
            'port' => getenv('DB_PORT') ?: 3306,
            'charset' => 'utf8mb4',
        ];

        try {
            $conn = DriverManager::getConnection($connectionParams);
            
            $stmt = $conn->prepare('
                SELECT n.*, c.first_name, c.last_name, c.email as customer_email
                FROM ws_newsletter n
                LEFT JOIN ws_customer c ON n.customer_id = c.id
                ORDER BY n.created_at DESC
            ');
            $stmt->execute();
            $subscribers = $stmt->fetchAllAssociative();
            
            $this->render('admin/newsletter/subscribers.html.twig', [
                'title' => 'Webshop Admin - Newsletter-Abonnenten',
                'subscribers' => $subscribers
            ]);
            
        } catch (Exception $e) {
            $this->render('admin/newsletter/subscribers.html.twig', [
                'title' => 'Webshop Admin - Newsletter-Abonnenten',
                'error' => 'Datenbankfehler: ' . $e->getMessage()
            ]);
        }
    }
    
    public function toggleSubscriber($id)
    {
        if (!isset($_SESSION['admin_id'])) {
            header('Location: /admin/login');
            exit;
        }
        
        $connectionParams = [
            'dbname' => getenv('DB_DATABASE') ?: 'freeshop',
            'user' => getenv('DB_USERNAME') ?: 'freeshop_user',
            'password' => getenv('DB_PASSWORD') ?: 'freeshop_password',
            'host' => getenv('DB_HOST') ?: 'db',
            'driver' => 'pdo_mysql',
            'port' => getenv('DB_PORT') ?: 3306,
            'charset' => 'utf8mb4',
        ];

        try {
            $conn = DriverManager::getConnection($connectionParams);
            
            $stmt = $conn->prepare('
                UPDATE ws_newsletter 
                SET active = NOT active, updated_at = NOW()
                WHERE id = ?
            ');
            $stmt->execute([$id]);
            
            header('Location: /admin/newsletter/subscribers?success=1');
            exit;
            
        } catch (Exception $e) {
            header('Location: /admin/newsletter/subscribers?error=' . urlencode($e->getMessage()));
            exit;
        }
    }

    protected function render($template, $data = [])
    {
        // Einfache Template-Engine (später durch Twig ersetzen)
        extract($data);
        include __DIR__ . '/../../templates/' . $template;
    }
}