<?php
require_once 'includes/config.php';
require_once 'includes/functions.php';
require_once 'includes/auth.php';
require_once 'includes/db.php';

$auth = new Auth();

// Check if user is logged in
if (!$auth->isLoggedIn()) {
    die('Unauthorized access');
}

$db = Database::getInstance();

// Get all attributes for headers
$attributes = $db->query("
    SELECT id, name 
    FROM attributes 
    ORDER BY created_at ASC
");

// Set headers for CSV download
header('Content-Type: text/csv; charset=utf-8');
header('Content-Disposition: attachment; filename="panel_data_' . date('Y-m-d') . '.csv"');

// Create output stream
$output = fopen('php://output', 'w');

// Add BOM for Excel UTF-8 compatibility
fprintf($output, chr(0xEF).chr(0xBB).chr(0xBF));

// Write headers
$headers = ['Panelist ID'];
while ($attr = $attributes->fetch_assoc()) {
    $headers[] = $attr['name'];
}
fputcsv($output, $headers);

// Get all panel data
$panel_query = $db->query("
    SELECT * 
    FROM panel_data 
    ORDER BY created_at ASC
");

// Write data rows
while ($panel = $panel_query->fetch_assoc()) {
    $row = [str_pad($panel['panelist_id'], 6, '0', STR_PAD_LEFT)];
    
    $attributes->data_seek(0); // Reset attributes pointer
    $values = json_decode($panel['attribute_values'], true);
    
    while ($attr = $attributes->fetch_assoc()) {
        $value = $values[$attr['id']] ?? '-';
        
        // Handle array values for multiple-choice attributes
        if (is_array($value)) {
            $value = implode(', ', $value);
        }
        
        $row[] = $value;
    }
    
    fputcsv($output, $row);
}

fclose($output);
exit;