get_leaderboard.php

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

    $servername = "localhost";
    $DBUsername = "root";
    $DBPassword = "root";
    $dbname = "new_unity";

    // Get JSON data from request body
    $json = file_get_contents('php://input');
    $data = json_decode($json, true);

    // Check if JSON was decoded successfully
    if ($data === null) {
        die(json_encode(array("success" => false, "message" => "Invalid JSON data")));
    }

    // Extract request parameters
    $difficulty = $data["difficulty"] ?? "NORMAL";
    $limit = isset($data["limit"]) ? intval($data["limit"]) : 10;

    // Connect to database
    $conn = new mysqli($servername, $DBUsername, $DBPassword, $dbname);

    if($conn->connect_error) {
        die(json_encode(array("success" => false, "message" => "Connection to database failed")));
    }

    try {
        // Query to get the top scores for the specified difficulty
        $query = "SELECT u.username, s.completion_time, s.difficulty, s.timestamp 
                 FROM scores s
                 JOIN users u ON s.user_id = u.user_id
                 WHERE s.difficulty = ?
                 ORDER BY s.completion_time ASC
                 LIMIT ?";
        
        $stmt = $conn->prepare($query);
        if (!$stmt) {
            die(json_encode(array("success" => false, "message" => "Failed to prepare leaderboard query: " . $conn->error)));
        }
        
        $stmt->bind_param("si", $difficulty, $limit);
        
        if (!$stmt->execute()) {
            die(json_encode(array("success" => false, "message" => "Leaderboard query failed: " . $stmt->error)));
        }
        
        $result = $stmt->get_result();
        
        $scores = array();
        while ($row = $result->fetch_assoc()) {
            $scores[] = array(
                "username" => $row["username"],
                "completion_time" => floatval($row["completion_time"]),
                "difficulty" => $row["difficulty"],
                "timestamp" => $row["timestamp"]
            );
        }
        
        $stmt->close();
        
        // Return the scores
        echo json_encode(array(
            "success" => true,
            "message" => "Leaderboard retrieved successfully",
            "scores" => $scores
        ));
        
    } catch(Exception $e) {
        die(json_encode(array("success" => false, "message" => "Database error: " . $e->getMessage())));
    }
    
    $conn->close();
?>