<?php
/**
 * API - Envío masivo de mensajes
 * Fecha: 13 de noviembre de 2025
 */

require_once '../config/config.php';

// Verificar autenticación
requireAuthentication();

header('Content-Type: application/json; charset=utf-8');
header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: POST');
header('Access-Control-Allow-Headers: Content-Type');

if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
    http_response_code(405);
    echo json_encode(['error' => 'Método no permitido']);
    exit;
}

try {
    $input = json_decode(file_get_contents('php://input'), true);
    
    if (!$input || !isset($input['message'])) {
        http_response_code(400);
        echo json_encode(['error' => 'Mensaje requerido']);
        exit;
    }
    
    $filter = $input['filter'] ?? 'all';
    $message = $input['message'];
    
    $db = Database::getInstance();
    $whatsappService = new WhatsAppService();
    
    // Construir query según filtro
    $whereClause = "WHERE u.status = 'active'";
    
    switch ($filter) {
        case 'active':
            $whereClause .= " AND EXISTS (
                SELECT 1 FROM conversations c 
                WHERE c.user_id = u.id 
                AND c.created_at >= DATE_SUB(NOW(), INTERVAL 7 DAY)
            )";
            break;
            
        case 'recent':
            $whereClause .= " AND u.created_at >= DATE_SUB(NOW(), INTERVAL 30 DAY)";
            break;
    }
    
    // Obtener usuarios según filtro
    $users = $db->fetchAll(
        "SELECT phone_number FROM users u " . $whereClause
    );
    
    $sentCount = 0;
    $errorCount = 0;
    
    foreach ($users as $user) {
        try {
            $response = $whatsappService->sendTextMessage($user['phone_number'], $message);
            if ($response) {
                $sentCount++;
            }
            
            // Pequeña pausa para no saturar la API
            usleep(100000); // 0.1 segundo
            
        } catch (Exception $e) {
            $errorCount++;
            error_log("Error sending broadcast to {$user['phone_number']}: " . $e->getMessage());
        }
    }
    
    echo json_encode([
        'success' => true,
        'sent_count' => $sentCount,
        'error_count' => $errorCount,
        'total_users' => count($users)
    ]);
    
} catch (Exception $e) {
    error_log("Error in send_broadcast.php: " . $e->getMessage());
    http_response_code(500);
    echo json_encode(['error' => 'Error interno del servidor: ' . $e->getMessage()]);
}
?>