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

header('Content-Type: application/json');

try {
    $auth = new Auth();
    if (!$auth->isLoggedIn()) {
        throw new Exception('Unauthorized');
    }

    $type = $_GET['type'] ?? 'possible';
    $limit = isset($_GET['limit']) ? (int)$_GET['limit'] : null;

    if (!in_array($type, ['possible', 'impossible'])) {
        throw new Exception('Invalid type. Must be "possible" or "impossible"');
    }

    $db = Database::getInstance();
    $combinations = getCombinations($db, $type, $limit);

    echo json_encode([
        'success' => true,
        'type' => $type,
        'count' => count($combinations),
        'combinations' => $combinations
    ]);

} catch (Exception $e) {
    http_response_code(500);
    echo json_encode([
        'success' => false,
        'message' => $e->getMessage()
    ]);
}

function getCombinations($db, $type, $limit) {
    try {
        $isImpossible = $type === 'impossible' ? 1 : 0;
        
        $sql = "SELECT 
                    id,
                    attribute1_id,
                    attribute2_id,
                    choice1,
                    choice2,
                    attribute1_name,
                    attribute2_name,
                    is_impossible,
                    llm_reasoning,
                    updated_at
                FROM panel_directives 
                WHERE llm_checked = 1 
                AND is_impossible = ?
                ORDER BY updated_at DESC";
        
        if ($limit) {
            $sql .= " LIMIT ?";
        }
        
        $stmt = $db->prepare($sql);
        
        if ($limit) {
            $stmt->bind_param('ii', $isImpossible, $limit);
        } else {
            $stmt->bind_param('i', $isImpossible);
        }
        
        $stmt->execute();
        $result = $stmt->get_result();
        
        $combinations = [];
        while ($row = $result->fetch_assoc()) {
            $combinations[] = [
                'id' => $row['id'],
                'attribute1_id' => $row['attribute1_id'],
                'attribute2_id' => $row['attribute2_id'],
                'choice1' => $row['choice1'],
                'choice2' => $row['choice2'],
                'attribute1_name' => $row['attribute1_name'],
                'attribute2_name' => $row['attribute2_name'],
                'is_impossible' => (bool)$row['is_impossible'],
                'reasoning' => $row['llm_reasoning'],
                'updated_at' => $row['updated_at'],
                'formatted_time' => formatTimeAgo($row['updated_at'])
            ];
        }
        
        return $combinations;
        
    } catch (Exception $e) {
        error_log("Error getting combinations: " . $e->getMessage());
        return [];
    }
}

function formatTimeAgo($datetime) {
    $time = time() - strtotime($datetime);
    
    if ($time < 60) {
        return 'Just now';
    } elseif ($time < 3600) {
        $minutes = floor($time / 60);
        return $minutes . ' minute' . ($minutes > 1 ? 's' : '') . ' ago';
    } elseif ($time < 86400) {
        $hours = floor($time / 3600);
        return $hours . ' hour' . ($hours > 1 ? 's' : '') . ' ago';
    } else {
        $days = floor($time / 86400);
        return $days . ' day' . ($days > 1 ? 's' : '') . ' ago';
    }
}
?>