<?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();

// Set headers for CSV download
header('Content-Type: text/csv; charset=utf-8');
header('Content-Disposition: attachment; filename="statistic_check_' . 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
$headers = ['Statistic Name', 'Combination', 'Target %', 'Panel %', 'Deviation %'];
fputcsv($output, $headers);

// Get all combinations data
$query = $db->query("
    SELECT 
        s.name as statistic_name,
        sc.combination_values,
        sc.percentage as target_percentage,
        sc.actual_percentage as panel_percentage
    FROM statistics s
    JOIN statistic_combinations sc ON s.id = sc.statistic_id
    ORDER BY s.name, sc.id
");

// Write data rows
while ($row = $query->fetch_assoc()) {
    $target_percentage = floatval($row['target_percentage']);
    $panel_percentage = floatval($row['panel_percentage'] ?? 0);
    
    // Calculate deviation percentage
    $deviation = $target_percentage > 0 ? 
        (($panel_percentage - $target_percentage) / $target_percentage) * 100 : 
        0;
    
    // Format the combination
    $values = json_decode($row['combination_values'], true);
    $combination = implode(' × ', $values);
    
    $csvRow = [
        $row['statistic_name'],
        $combination,
        number_format($target_percentage, 2),
        number_format($panel_percentage, 2),
        number_format($deviation, 2)
    ];
    
    fputcsv($output, $csvRow);
}

fclose($output);
exit;