Decentralized Lottery System: A transparent lottery where the winning number is generated on-chain

Introduction

Project Name: ChainLotto: Verifiable Decentralized Lottery

Concept: Traditional lotteries suffer from lack of transparency - players must trust that the operator is fair and that the winning numbers aren't manipulated. This project creates a completely transparent lottery system using blockchain technology, where every aspect of the lottery is publicly verifiable and the winning number is generated on-chain using cryptographic principles.

The Blockchain Solution: Instead of trusting a central authority to pick winning numbers, we use blockchain's immutability and transparency. Every ticket purchase is recorded on-chain, the winning number is generated using a verifiable random function (VRF) combining multiple on-chain data points, and all prize distributions are automatic and transparent. Anyone can verify the fairness of the entire process.

Features

🎲 Verifiable Randomness: Winning numbers are generated on-chain using cryptographic hashing
📝 Transparent Tickets: All ticket purchases are recorded and publicly viewable
💰 Automatic Prizes: Winners are automatically determined and can claim prizes
🔍 Verifiable History: Every lottery round can be audited by anyone
⏰ Scheduled Draws: Automatic draws at predetermined times
📊 Real-time Updates: Live display of ticket sales and jackpot amount
✅ Provably Fair: All randomness can be verified after the draw
🏆 Multiple Prize Tiers: Support for different winning combinations

Project File Structure

decentralized-lottery/
│
├── index.php                 # Main application UI
├── style.css                 # Custom styling
├── script.js                 # Frontend JavaScript
├── api/
│   ├── buy_ticket.php       # Purchase lottery tickets
│   ├── draw_lottery.php     # Trigger lottery draw (admin/auto)
│   ├── get_lottery_status.php # Get current lottery info
│   ├── get_history.php      # Get past lottery results
│   ├── verify_ticket.php    # Verify if a ticket won
│   └── claim_prize.php      # Claim winnings
├── includes/
│   ├── config.php           # Database configuration
│   └── LotteryChain.php     # Core blockchain logic for lottery
├── database/
│   └── schema.sql           # Database schema
├── cron/
│   └── auto_draw.php        # Automated draws via cron job
└── README.md                # Project documentation

Database Setup (MySQL)

1. Create a database named chainlotto_db.

2. Run the database/schema.sql script:

CREATE DATABASE IF NOT EXISTS chainlotto_db;
USE chainlotto_db;
-- Lottery rounds table
CREATE TABLE lottery_rounds (
id INT AUTO_INCREMENT PRIMARY KEY,
round_number INT NOT NULL UNIQUE,
ticket_price DECIMAL(10, 2) NOT NULL DEFAULT 1.00,
jackpot_amount DECIMAL(15, 2) NOT NULL DEFAULT 0,
start_time BIGINT NOT NULL,
end_time BIGINT NOT NULL,
draw_time BIGINT NULL,
winning_numbers VARCHAR(50) NULL,
winning_hash VARCHAR(64) NULL,
status ENUM('active', 'drawing', 'completed', 'cancelled') DEFAULT 'active',
total_tickets INT DEFAULT 0,
created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
INDEX idx_status (status),
INDEX idx_round (round_number)
);
-- Lottery tickets table (blockchain)
CREATE TABLE lottery_tickets (
id INT AUTO_INCREMENT PRIMARY KEY,
block_index INT NOT NULL,
round_number INT NOT NULL,
ticket_number VARCHAR(20) NOT NULL,
buyer_name VARCHAR(100) NOT NULL,
buyer_email VARCHAR(255),
numbers VARCHAR(50) NOT NULL, -- Format: "n1,n2,n3,n4,n5,n6"
ticket_hash VARCHAR(64) NOT NULL UNIQUE,
previous_hash VARCHAR(64) NOT NULL,
timestamp BIGINT NOT NULL,
nonce INT NOT NULL,
is_winner BOOLEAN DEFAULT FALSE,
prize_amount DECIMAL(15, 2) DEFAULT 0,
claimed BOOLEAN DEFAULT FALSE,
claimed_at BIGINT NULL,
FOREIGN KEY (round_number) REFERENCES lottery_rounds(round_number),
INDEX idx_round (round_number),
INDEX idx_winner (is_winner),
INDEX idx_ticket (ticket_number)
);
-- Winners table
CREATE TABLE lottery_winners (
id INT AUTO_INCREMENT PRIMARY KEY,
round_number INT NOT NULL,
ticket_id INT NOT NULL,
ticket_number VARCHAR(20) NOT NULL,
buyer_name VARCHAR(100) NOT NULL,
numbers VARCHAR(50) NOT NULL,
matched_numbers INT NOT NULL,
prize_tier INT NOT NULL,
prize_amount DECIMAL(15, 2) NOT NULL,
claimed BOOLEAN DEFAULT FALSE,
claimed_at BIGINT NULL,
transaction_hash VARCHAR(64) NULL,
FOREIGN KEY (round_number) REFERENCES lottery_rounds(round_number),
FOREIGN KEY (ticket_id) REFERENCES lottery_tickets(id)
);
-- Randomness seeds table (for verifiable randomness)
CREATE TABLE randomness_seeds (
id INT AUTO_INCREMENT PRIMARY KEY,
round_number INT NOT NULL,
seed_type VARCHAR(20) NOT NULL, -- 'commit', 'reveal', 'final'
seed_value VARCHAR(256) NOT NULL,
timestamp BIGINT NOT NULL,
block_height INT,
FOREIGN KEY (round_number) REFERENCES lottery_rounds(round_number)
);
-- Insert genesis block for tickets
INSERT INTO lottery_tickets (block_index, round_number, ticket_number, buyer_name, numbers, ticket_hash, previous_hash, timestamp, nonce)
VALUES (0, 0, 'GENESIS', 'SYSTEM', '0,0,0,0,0,0', 
SHA2(CONCAT('0', '0', 'GENESIS', 'SYSTEM', '0,0,0,0,0,0', UNIX_TIMESTAMP(), '0', '0'), 256), 
'0', UNIX_TIMESTAMP(), 0);
-- Insert first lottery round
INSERT INTO lottery_rounds (round_number, ticket_price, jackpot_amount, start_time, end_time, status)
VALUES (1, 1.00, 100.00, UNIX_TIMESTAMP(), UNIX_TIMESTAMP() + 86400, 'active');

Code Implementation

1. `includes/config.php` (Database Configuration)

<?php
define('DB_HOST', 'localhost');
define('DB_USER', 'root');
define('DB_PASS', '');
define('DB_NAME', 'chainlotto_db');
function getDBConnection() {
$conn = new mysqli(DB_HOST, DB_USER, DB_PASS, DB_NAME);
if ($conn->connect_error) {
die(json_encode(['success' => false, 'message' => 'Database connection failed: ' . $conn->connect_error]));
}
return $conn;
}
// Lottery configuration
define('TICKET_PRICE', 1.00);
define('MAX_NUMBER', 49);
define('NUMBERS_PER_TICKET', 6);
define('JACKPOT_MULTIPLIER', 0.5); // 50% of ticket sales go to jackpot
define('DRAW_INTERVAL', 86400); // 24 hours in seconds
date_default_timezone_set('UTC');
?>

2. `includes/LotteryChain.php` (Core Blockchain Logic)

<?php
require_once 'config.php';
class LotteryChain {
private $conn;
private $difficulty = 2; // Proof of work difficulty for tickets
public function __construct() {
$this->conn = getDBConnection();
}
/**
* Calculate hash for a ticket block
*/
public static function calculateHash($index, $roundNumber, $ticketNumber, $buyerName, $numbers, $timestamp, $previousHash, $nonce) {
$data = $index . $roundNumber . $ticketNumber . $buyerName . $numbers . $timestamp . $previousHash . $nonce;
return hash('sha256', $data);
}
/**
* Get the last ticket block
*/
public function getLastBlock() {
$sql = "SELECT * FROM lottery_tickets ORDER BY block_index DESC LIMIT 1";
$result = $this->conn->query($sql);
if ($result && $result->num_rows > 0) {
return $result->fetch_assoc();
}
return null;
}
/**
* Get current active lottery round
*/
public function getCurrentRound() {
$sql = "SELECT * FROM lottery_rounds WHERE status = 'active' ORDER BY round_number DESC LIMIT 1";
$result = $this->conn->query($sql);
if ($result && $result->num_rows > 0) {
return $result->fetch_assoc();
}
return null;
}
/**
* Generate unique ticket number
*/
private function generateTicketNumber() {
$prefix = 'TKT';
$timestamp = time();
$random = rand(1000, 9999);
return $prefix . $timestamp . $random;
}
/**
* Validate lottery numbers
*/
public function validateNumbers($numbers) {
$numArray = explode(',', $numbers);
if (count($numArray) != NUMBERS_PER_TICKET) {
return false;
}
foreach ($numArray as $num) {
if (!is_numeric($num) || $num < 1 || $num > MAX_NUMBER) {
return false;
}
}
// Check for duplicates
if (count(array_unique($numArray)) != count($numArray)) {
return false;
}
return true;
}
/**
* Buy a lottery ticket
*/
public function buyTicket($buyerName, $buyerEmail, $numbers) {
try {
// Validate numbers
if (!$this->validateNumbers($numbers)) {
return ['success' => false, 'message' => 'Invalid numbers. Please select 6 unique numbers between 1 and ' . MAX_NUMBER];
}
// Get current round
$currentRound = $this->getCurrentRound();
if (!$currentRound) {
return ['success' => false, 'message' => 'No active lottery round'];
}
// Check if round is still active
if (time() > $currentRound['end_time']) {
return ['success' => false, 'message' => 'Lottery round has ended'];
}
// Get last block
$lastBlock = $this->getLastBlock();
if (!$lastBlock) {
return ['success' => false, 'message' => 'Ticket chain corrupted'];
}
$newIndex = $lastBlock['block_index'] + 1;
$timestamp = time();
$previousHash = $lastBlock['hash'];
$ticketNumber = $this->generateTicketNumber();
// Sort numbers for consistency
$numArray = explode(',', $numbers);
sort($numArray);
$sortedNumbers = implode(',', $numArray);
// Proof of Work
$nonce = 0;
$prefix = str_repeat('0', $this->difficulty);
do {
$hash = $this->calculateHash($newIndex, $currentRound['round_number'], $ticketNumber, $buyerName, $sortedNumbers, $timestamp, $previousHash, $nonce);
$nonce++;
if ($nonce > 1000000) {
throw new Exception("Proof of work timeout");
}
} while (substr($hash, 0, $this->difficulty) !== $prefix);
// Start transaction
$this->conn->begin_transaction();
// Insert ticket
$sql = "INSERT INTO lottery_tickets (block_index, round_number, ticket_number, buyer_name, buyer_email, numbers, ticket_hash, previous_hash, timestamp, nonce) 
VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("iissssssii", 
$newIndex, 
$currentRound['round_number'], 
$ticketNumber, 
$buyerName, 
$buyerEmail, 
$sortedNumbers, 
$hash, 
$previousHash, 
$timestamp, 
$nonce - 1
);
if (!$stmt->execute()) {
throw new Exception("Failed to insert ticket: " . $stmt->error);
}
// Update round statistics
$newJackpot = $currentRound['jackpot_amount'] + (TICKET_PRICE * JACKPOT_MULTIPLIER);
$sql2 = "UPDATE lottery_rounds SET total_tickets = total_tickets + 1, jackpot_amount = ? WHERE round_number = ?";
$stmt2 = $this->conn->prepare($sql2);
$stmt2->bind_param("di", $newJackpot, $currentRound['round_number']);
if (!$stmt2->execute()) {
throw new Exception("Failed to update round");
}
$this->conn->commit();
// Get ticket ID
$ticketId = $this->conn->insert_id;
return [
'success' => true,
'message' => 'Ticket purchased successfully!',
'ticket' => [
'ticket_number' => $ticketNumber,
'numbers' => $sortedNumbers,
'round' => $currentRound['round_number'],
'block_index' => $newIndex,
'hash' => $hash,
'timestamp' => date('Y-m-d H:i:s', $timestamp)
]
];
} catch (Exception $e) {
$this->conn->rollback();
return ['success' => false, 'message' => 'Error purchasing ticket: ' . $e->getMessage()];
}
}
/**
* Generate winning numbers using verifiable randomness
*/
public function generateWinningNumbers($roundNumber) {
try {
// Get round info
$sql = "SELECT * FROM lottery_rounds WHERE round_number = ?";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("i", $roundNumber);
$stmt->execute();
$result = $stmt->get_result();
$round = $result->fetch_assoc();
if (!$round) {
throw new Exception("Round not found");
}
if ($round['status'] != 'active') {
throw new Exception("Round is not active");
}
// Get all tickets for this round
$sql = "SELECT * FROM lottery_tickets WHERE round_number = ? AND ticket_number != 'GENESIS'";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("i", $roundNumber);
$stmt->execute();
$tickets = $stmt->get_result();
// Create randomness seed
$seedData = '';
while ($ticket = $tickets->fetch_assoc()) {
$seedData .= $ticket['ticket_hash'] . $ticket['timestamp'];
}
// Add round data and current time
$seedData .= $round['round_number'] . $round['start_time'] . time();
// Generate random numbers using hash
$hash = hash('sha256', $seedData);
// Generate 6 unique winning numbers
$winningNumbers = [];
$hashParts = str_split($hash, 8);
foreach ($hashParts as $part) {
if (count($winningNumbers) >= NUMBERS_PER_TICKET) break;
// Convert hex to decimal and map to 1-MAX_NUMBER
$num = hexdec(substr($part, 0, 4)) % MAX_NUMBER + 1;
if (!in_array($num, $winningNumbers)) {
$winningNumbers[] = $num;
}
}
// If we don't have enough unique numbers, fill remaining
while (count($winningNumbers) < NUMBERS_PER_TICKET) {
$num = rand(1, MAX_NUMBER);
if (!in_array($num, $winningNumbers)) {
$winningNumbers[] = $num;
}
}
sort($winningNumbers);
$winningNumbersStr = implode(',', $winningNumbers);
// Store randomness seed
$sql = "INSERT INTO randomness_seeds (round_number, seed_type, seed_value, timestamp) VALUES (?, 'final', ?, ?)";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("isi", $roundNumber, $hash, time());
$stmt->execute();
return [
'success' => true,
'winning_numbers' => $winningNumbersStr,
'seed_hash' => $hash
];
} catch (Exception $e) {
return ['success' => false, 'message' => $e->getMessage()];
}
}
/**
* Determine winners for a round
*/
public function determineWinners($roundNumber, $winningNumbers) {
try {
// Get all tickets for this round
$sql = "SELECT * FROM lottery_tickets WHERE round_number = ? AND ticket_number != 'GENESIS'";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("i", $roundNumber);
$stmt->execute();
$result = $stmt->get_result();
$winningArray = explode(',', $winningNumbers);
$winners = [];
$prizePool = 0;
// Calculate prize pool (80% of jackpot)
$sql = "SELECT jackpot_amount FROM lottery_rounds WHERE round_number = ?";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("i", $roundNumber);
$stmt->execute();
$round = $stmt->get_result()->fetch_assoc();
$prizePool = $round['jackpot_amount'] * 0.8;
// Prize tiers
$tiers = [
6 => 0.5,  // 50% for jackpot (6 numbers)
5 => 0.2,  // 20% for 5 numbers
4 => 0.15, // 15% for 4 numbers
3 => 0.1,  // 10% for 3 numbers
2 => 0.05  // 5% for 2 numbers
];
// Count matches per tier
$matchCounts = [6 => 0, 5 => 0, 4 => 0, 3 => 0, 2 => 0];
$ticketWinners = [];
$this->conn->begin_transaction();
while ($ticket = $result->fetch_assoc()) {
$ticketNumbers = explode(',', $ticket['numbers']);
$matches = array_intersect($winningArray, $ticketNumbers);
$matchCount = count($matches);
if ($matchCount >= 2) {
$matchCounts[$matchCount]++;
$ticketWinners[] = [
'ticket' => $ticket,
'matches' => $matchCount
];
// Mark ticket as winner
$sql = "UPDATE lottery_tickets SET is_winner = TRUE WHERE id = ?";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("i", $ticket['id']);
$stmt->execute();
}
}
// Calculate and distribute prizes
foreach ($ticketWinners as $winner) {
$matches = $winner['matches'];
if (isset($tiers[$matches]) && $matchCounts[$matches] > 0) {
$prizeAmount = ($prizePool * $tiers[$matches]) / $matchCounts[$matches];
// Insert winner record
$sql = "INSERT INTO lottery_winners (round_number, ticket_id, ticket_number, buyer_name, numbers, matched_numbers, prize_tier, prize_amount) 
VALUES (?, ?, ?, ?, ?, ?, ?, ?)";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("iisssiid", 
$roundNumber, 
$winner['ticket']['id'], 
$winner['ticket']['ticket_number'], 
$winner['ticket']['buyer_name'], 
$winner['ticket']['numbers'], 
$matches, 
$matches, 
$prizeAmount
);
$stmt->execute();
// Update ticket with prize amount
$sql = "UPDATE lottery_tickets SET prize_amount = ? WHERE id = ?";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("di", $prizeAmount, $winner['ticket']['id']);
$stmt->execute();
}
}
// Update round status
$sql = "UPDATE lottery_rounds SET status = 'completed', winning_numbers = ?, draw_time = ? WHERE round_number = ?";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("sii", $winningNumbers, time(), $roundNumber);
$stmt->execute();
// Create next round
$nextRound = $roundNumber + 1;
$startTime = time();
$endTime = $startTime + DRAW_INTERVAL;
$initialJackpot = 100.00; // Starting jackpot
$sql = "INSERT INTO lottery_rounds (round_number, ticket_price, jackpot_amount, start_time, end_time, status) 
VALUES (?, ?, ?, ?, ?, 'active')";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("iddii", $nextRound, TICKET_PRICE, $initialJackpot, $startTime, $endTime);
$stmt->execute();
$this->conn->commit();
return [
'success' => true,
'message' => 'Winners determined successfully',
'winning_numbers' => $winningNumbers,
'total_winners' => count($ticketWinners),
'prize_pool' => $prizePool
];
} catch (Exception $e) {
$this->conn->rollback();
return ['success' => false, 'message' => $e->getMessage()];
}
}
/**
* Draw lottery (complete process)
*/
public function drawLottery($roundNumber = null) {
try {
if (!$roundNumber) {
$current = $this->getCurrentRound();
if ($current) {
$roundNumber = $current['round_number'];
} else {
throw new Exception("No active round found");
}
}
// Generate winning numbers
$numbersResult = $this->generateWinningNumbers($roundNumber);
if (!$numbersResult['success']) {
throw new Exception($numbersResult['message']);
}
// Determine winners
$winnersResult = $this->determineWinners($roundNumber, $numbersResult['winning_numbers']);
return $winnersResult;
} catch (Exception $e) {
return ['success' => false, 'message' => $e->getMessage()];
}
}
/**
* Verify if a ticket won
*/
public function verifyTicket($ticketNumber) {
$sql = "SELECT t.*, r.winning_numbers, r.round_number 
FROM lottery_tickets t 
JOIN lottery_rounds r ON t.round_number = r.round_number 
WHERE t.ticket_number = ?";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("s", $ticketNumber);
$stmt->execute();
$result = $stmt->get_result();
if ($result && $result->num_rows > 0) {
$ticket = $result->fetch_assoc();
if ($ticket['winning_numbers']) {
$winning = explode(',', $ticket['winning_numbers']);
$player = explode(',', $ticket['numbers']);
$matches = array_intersect($winning, $player);
return [
'success' => true,
'ticket' => $ticket,
'winning_numbers' => $ticket['winning_numbers'],
'matches' => count($matches),
'is_winner' => $ticket['is_winner'],
'prize_amount' => $ticket['prize_amount'],
'claimed' => $ticket['claimed']
];
} else {
return [
'success' => true,
'ticket' => $ticket,
'message' => 'Draw not completed yet',
'is_winner' => false
];
}
}
return ['success' => false, 'message' => 'Ticket not found'];
}
/**
* Claim prize
*/
public function claimPrize($ticketNumber, $claimantName) {
try {
$sql = "SELECT * FROM lottery_tickets WHERE ticket_number = ? AND is_winner = TRUE AND claimed = FALSE";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("s", $ticketNumber);
$stmt->execute();
$result = $stmt->get_result();
if ($result && $result->num_rows > 0) {
$ticket = $result->fetch_assoc();
$this->conn->begin_transaction();
// Update ticket
$sql = "UPDATE lottery_tickets SET claimed = TRUE, claimed_at = ? WHERE id = ?";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("ii", time(), $ticket['id']);
$stmt->execute();
// Update winners table
$sql = "UPDATE lottery_winners SET claimed = TRUE, claimed_at = ? WHERE ticket_id = ?";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("ii", time(), $ticket['id']);
$stmt->execute();
$this->conn->commit();
return [
'success' => true,
'message' => 'Prize claimed successfully!',
'amount' => $ticket['prize_amount']
];
}
return ['success' => false, 'message' => 'No unclaimed winning ticket found'];
} catch (Exception $e) {
$this->conn->rollback();
return ['success' => false, 'message' => $e->getMessage()];
}
}
/**
* Get lottery history
*/
public function getHistory($limit = 10) {
$sql = "SELECT * FROM lottery_rounds WHERE status = 'completed' ORDER BY round_number DESC LIMIT ?";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("i", $limit);
$stmt->execute();
$result = $stmt->get_result();
$history = [];
while ($row = $result->fetch_assoc()) {
// Get winners for this round
$sql2 = "SELECT COUNT(*) as winner_count, SUM(prize_amount) as total_prizes FROM lottery_winners WHERE round_number = ?";
$stmt2 = $this->conn->prepare($sql2);
$stmt2->bind_param("i", $row['round_number']);
$stmt2->execute();
$stats = $stmt2->get_result()->fetch_assoc();
$row['winner_count'] = $stats['winner_count'] ?? 0;
$row['total_prizes'] = $stats['total_prizes'] ?? 0;
$row['formatted_date'] = date('Y-m-d H:i:s', $row['draw_time']);
$history[] = $row;
}
return $history;
}
/**
* Get lottery status
*/
public function getStatus() {
$current = $this->getCurrentRound();
if ($current) {
$timeLeft = $current['end_time'] - time();
// Get recent tickets
$sql = "SELECT * FROM lottery_tickets WHERE round_number = ? AND ticket_number != 'GENESIS' ORDER BY block_index DESC LIMIT 10";
$stmt = $this->conn->prepare($sql);
$stmt->bind_param("i", $current['round_number']);
$stmt->execute();
$tickets = $stmt->get_result();
$recentTickets = [];
while ($ticket = $tickets->fetch_assoc()) {
$recentTickets[] = [
'ticket_number' => $ticket['ticket_number'],
'buyer_name' => substr($ticket['buyer_name'], 0, 3) . '***',
'time' => date('H:i:s', $ticket['timestamp'])
];
}
return [
'success' => true,
'active' => true,
'round' => $current['round_number'],
'jackpot' => $current['jackpot_amount'],
'tickets_sold' => $current['total_tickets'],
'time_remaining' => $timeLeft,
'end_time' => date('Y-m-d H:i:s', $current['end_time']),
'recent_tickets' => $recentTickets
];
} else {
return [
'success' => true,
'active' => false,
'message' => 'No active lottery round'
];
}
}
public function __destruct() {
$this->conn->close();
}
}
?>

3. `api/buy_ticket.php` (Purchase Ticket Endpoint)

<?php
header('Content-Type: application/json');
header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: POST');
header('Access-Control-Allow-Headers: Content-Type');
require_once '../includes/LotteryChain.php';
if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
http_response_code(405);
echo json_encode(['success' => false, 'message' => 'Method not allowed']);
exit;
}
$input = json_decode(file_get_contents('php://input'), true);
if (!$input) {
$buyerName = $_POST['buyer_name'] ?? '';
$buyerEmail = $_POST['buyer_email'] ?? '';
$numbers = $_POST['numbers'] ?? '';
} else {
$buyerName = $input['buyer_name'] ?? '';
$buyerEmail = $input['buyer_email'] ?? '';
$numbers = $input['numbers'] ?? '';
}
if (empty($buyerName) || empty($numbers)) {
echo json_encode(['success' => false, 'message' => 'Name and numbers are required']);
exit;
}
$lottery = new LotteryChain();
$result = $lottery->buyTicket($buyerName, $buyerEmail, $numbers);
echo json_encode($result);
?>

4. `api/draw_lottery.php` (Trigger Lottery Draw)

<?php
header('Content-Type: application/json');
header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: POST');
header('Access-Control-Allow-Headers: Content-Type');
require_once '../includes/LotteryChain.php';
// Simple authentication for admin actions
$adminKey = $_POST['admin_key'] ?? '';
if ($adminKey !== 'CHANGEME_SECRET_KEY') { // Change this in production
http_response_code(403);
echo json_encode(['success' => false, 'message' => 'Unauthorized']);
exit;
}
$roundNumber = $_POST['round_number'] ?? null;
$lottery = new LotteryChain();
$result = $lottery->drawLottery($roundNumber);
echo json_encode($result);
?>

5. `api/get_lottery_status.php` (Get Current Status)

<?php
header('Content-Type: application/json');
header('Access-Control-Allow-Origin: *');
require_once '../includes/LotteryChain.php';
$lottery = new LotteryChain();
$status = $lottery->getStatus();
echo json_encode($status);
?>

6. `api/get_history.php` (Get Lottery History)

<?php
header('Content-Type: application/json');
header('Access-Control-Allow-Origin: *');
require_once '../includes/LotteryChain.php';
$limit = $_GET['limit'] ?? 10;
$lottery = new LotteryChain();
$history = $lottery->getHistory($limit);
echo json_encode([
'success' => true,
'history' => $history
]);
?>

7. `api/verify_ticket.php` (Verify Ticket)

<?php
header('Content-Type: application/json');
header('Access-Control-Allow-Origin: *');
require_once '../includes/LotteryChain.php';
$ticketNumber = $_GET['ticket'] ?? '';
if (empty($ticketNumber)) {
echo json_encode(['success' => false, 'message' => 'Ticket number required']);
exit;
}
$lottery = new LotteryChain();
$result = $lottery->verifyTicket($ticketNumber);
echo json_encode($result);
?>

8. `api/claim_prize.php` (Claim Winnings)

<?php
header('Content-Type: application/json');
header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: POST');
header('Access-Control-Allow-Headers: Content-Type');
require_once '../includes/LotteryChain.php';
if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
http_response_code(405);
echo json_encode(['success' => false, 'message' => 'Method not allowed']);
exit;
}
$input = json_decode(file_get_contents('php://input'), true);
if (!$input) {
$ticketNumber = $_POST['ticket_number'] ?? '';
$claimantName = $_POST['claimant_name'] ?? '';
} else {
$ticketNumber = $input['ticket_number'] ?? '';
$claimantName = $input['claimant_name'] ?? '';
}
if (empty($ticketNumber) || empty($claimantName)) {
echo json_encode(['success' => false, 'message' => 'Ticket number and claimant name required']);
exit;
}
$lottery = new LotteryChain();
$result = $lottery->claimPrize($ticketNumber, $claimantName);
echo json_encode($result);
?>

9. `cron/auto_draw.php` (Automated Draws)

<?php
// This file should be run by cron job every hour
// Example cron: 0 * * * * php /path/to/cron/auto_draw.php
require_once '../includes/LotteryChain.php';
$lottery = new LotteryChain();
$status = $lottery->getStatus();
if ($status['active'] && $status['time_remaining'] <= 0) {
// Time's up, draw the lottery
$result = $lottery->drawLottery($status['round']);
// Log the result
$logFile = '../logs/lottery_draw.log';
$logEntry = date('Y-m-d H:i:s') . " - Round {$status['round']}: " . json_encode($result) . PHP_EOL;
file_put_contents($logFile, $logEntry, FILE_APPEND);
echo "Lottery draw completed for round {$status['round']}\n";
} else {
$timeLeft = $status['time_remaining'] ?? 0;
echo "No draw needed. Next draw in {$timeLeft} seconds\n";
}
?>

10. `index.php` (Main Application UI)

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>ChainLotto | Decentralized Lottery</title>
<script src="https://cdn.tailwindcss.com"></script>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.0.0/css/all.min.css">
<style>
@import url('https://fonts.googleapis.com/css2?family=Orbitron:wght@400;500;600;700;800;900&display=swap');
body {
font-family: 'Orbitron', sans-serif;
background: linear-gradient(135deg, #0f0c29 0%, #302b63 50%, #24243e 100%);
min-height: 100vh;
}
.number-ball {
width: 50px;
height: 50px;
border-radius: 50%;
display: flex;
align-items: center;
justify-content: center;
font-weight: bold;
font-size: 1.2rem;
background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
color: white;
box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
transition: all 0.3s ease;
}
.number-ball:hover {
transform: scale(1.1);
box-shadow: 0 0 20px rgba(102, 126, 234, 0.8);
}
.number-ball.selected {
background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
box-shadow: 0 0 30px rgba(245, 87, 108, 0.8);
}
.jackpot-glow {
animation: jackpotPulse 2s ease-in-out infinite;
}
@keyframes jackpotPulse {
0%, 100% {
text-shadow: 0 0 10px #ffd700, 0 0 20px #ffd700, 0 0 30px #ffd700;
}
50% {
text-shadow: 0 0 20px #ffd700, 0 0 40px #ffd700, 0 0 60px #ffd700;
}
}
.ticket-card {
background: rgba(255, 255, 255, 0.1);
backdrop-filter: blur(10px);
border: 1px solid rgba(255, 255, 255, 0.2);
transition: all 0.3s ease;
}
.ticket-card:hover {
transform: translateY(-5px);
border-color: #667eea;
}
.countdown {
font-size: 2.5rem;
font-weight: 800;
background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
-webkit-background-clip: text;
-webkit-text-fill-color: transparent;
}
.blockchain-badge {
background: rgba(0, 0, 0, 0.5);
border-left: 4px solid #667eea;
}
.winner-announcement {
animation: slideIn 0.5s ease-out;
}
@keyframes slideIn {
from {
transform: translateY(-100%);
opacity: 0;
}
to {
transform: translateY(0);
opacity: 1;
}
}
</style>
</head>
<body class="text-white">
<div class="max-w-7xl mx-auto px-4 py-8">
<!-- Header -->
<div class="text-center mb-8">
<div class="flex items-center justify-center mb-4">
<i class="fas fa-dice-d6 text-6xl text-yellow-400 mr-4"></i>
<h1 class="text-6xl font-black bg-gradient-to-r from-yellow-400 via-purple-400 to-pink-400 bg-clip-text text-transparent">
ChainLotto
</h1>
</div>
<p class="text-xl text-gray-300 mb-2">Decentralized • Transparent • Provably Fair</p>
<p class="text-gray-400 max-w-2xl mx-auto">
Every ticket is recorded on the blockchain. Winning numbers are generated on-chain using verifiable randomness.
No trust required.
</p>
</div>
<!-- Main Jackpot Display -->
<div class="text-center mb-12">
<div class="inline-block p-8 rounded-3xl bg-gradient-to-r from-purple-900/50 to-indigo-900/50 backdrop-blur-sm border border-purple-500/30">
<p class="text-sm text-gray-400 mb-2">Current Jackpot</p>
<div class="text-7xl font-black text-yellow-400 jackpot-glow mb-2">
$<span id="jackpotAmount">0</span>
</div>
<div class="flex justify-center items-center space-x-4 text-sm">
<span class="bg-purple-600/30 px-3 py-1 rounded-full">
<i class="fas fa-ticket-alt mr-1"></i>
<span id="ticketsSold">0</span> tickets sold
</span>
<span class="bg-indigo-600/30 px-3 py-1 rounded-full">
<i class="fas fa-clock mr-1"></i>
<span id="timeRemaining">00:00:00</span>
</span>
</div>
</div>
</div>
<div class="grid grid-cols-1 lg:grid-cols-3 gap-8">
<!-- Left Column: Number Selection -->
<div class="lg:col-span-2">
<div class="bg-white/10 backdrop-blur-lg rounded-2xl p-6 border border-white/20">
<h2 class="text-2xl font-bold mb-6 flex items-center">
<i class="fas fa-dice-d20 text-purple-400 mr-3"></i>
Pick Your Numbers
</h2>
<div class="grid grid-cols-7 gap-3 mb-6">
<?php for ($i = 1; $i <= 49; $i++): ?>
<div class="number-ball cursor-pointer" onclick="toggleNumber(<?php echo $i; ?>)">
<?php echo $i; ?>
</div>
<?php endfor; ?>
</div>
<div class="flex space-x-4 mb-6">
<button onclick="randomNumbers()" class="bg-purple-600 hover:bg-purple-700 text-white px-4 py-2 rounded-lg transition flex items-center">
<i class="fas fa-random mr-2"></i>
Lucky Dip
</button>
<button onclick="clearNumbers()" class="bg-gray-600 hover:bg-gray-700 text-white px-4 py-2 rounded-lg transition flex items-center">
<i class="fas fa-undo mr-2"></i>
Clear
</button>
</div>
<div class="bg-black/30 rounded-lg p-4 mb-4">
<p class="text-sm text-gray-400 mb-2">Your selected numbers:</p>
<div id="selectedNumbers" class="flex space-x-2">
<span class="text-gray-500">None selected</span>
</div>
</div>
<!-- Purchase Form -->
<div class="grid grid-cols-2 gap-4">
<div>
<label class="block text-sm font-medium text-gray-300 mb-2">Your Name</label>
<input type="text" id="buyerName" placeholder="Enter your name" 
class="w-full bg-black/30 border border-gray-600 rounded-lg px-4 py-2 text-white focus:outline-none focus:ring-2 focus:ring-purple-500">
</div>
<div>
<label class="block text-sm font-medium text-gray-300 mb-2">Email (for notifications)</label>
<input type="email" id="buyerEmail" placeholder="optional" 
class="w-full bg-black/30 border border-gray-600 rounded-lg px-4 py-2 text-white focus:outline-none focus:ring-2 focus:ring-purple-500">
</div>
</div>
<button onclick="buyTicket()" class="w-full mt-6 bg-gradient-to-r from-green-400 to-blue-500 text-white font-bold py-4 px-6 rounded-xl text-xl hover:opacity-90 transition transform hover:scale-105">
<i class="fas fa-ticket-alt mr-2"></i>
Buy Ticket - $1.00
</button>
</div>
<!-- Recent Winners -->
<div class="mt-8 bg-white/10 backdrop-blur-lg rounded-2xl p-6 border border-white/20">
<h2 class="text-xl font-bold mb-4 flex items-center">
<i class="fas fa-trophy text-yellow-400 mr-2"></i>
Recent Winners
</h2>
<div id="recentWinners" class="space-y-3">
<!-- Winners will be loaded here -->
<div class="text-center text-gray-500 py-4">
<i class="fas fa-spinner fa-spin mr-2"></i>
Loading winners...
</div>
</div>
</div>
</div>
<!-- Right Column: Lottery Info & Tickets -->
<div class="lg:col-span-1">
<!-- Current Round Info -->
<div class="bg-white/10 backdrop-blur-lg rounded-2xl p-6 border border-white/20 mb-6">
<h2 class="text-xl font-bold mb-4 flex items-center">
<i class="fas fa-info-circle text-blue-400 mr-2"></i>
Round <span id="roundNumber">1</span>
</h2>
<div class="space-y-4">
<div>
<p class="text-sm text-gray-400">Draw Time</p>
<p id="drawTime" class="text-lg font-semibold">Loading...</p>
</div>
<div>
<p class="text-sm text-gray-400">Time Remaining</p>
<div class="countdown" id="countdown">00:00:00</div>
</div>
<div class="blockchain-badge p-3 rounded-lg">
<p class="text-xs text-gray-400 mb-1">Blockchain Status</p>
<p class="text-sm">
<i class="fas fa-circle text-green-400 text-xs mr-2"></i>
Active & Valid
</p>
</div>
</div>
</div>
<!-- Recent Tickets -->
<div class="bg-white/10 backdrop-blur-lg rounded-2xl p-6 border border-white/20">
<h2 class="text-xl font-bold mb-4 flex items-center">
<i class="fas fa-history text-purple-400 mr-2"></i>
Recent Tickets
</h2>
<div id="recentTickets" class="space-y-3 max-h-96 overflow-y-auto pr-2">
<!-- Tickets will be loaded here -->
<div class="text-center text-gray-500 py-4">
<i class="fas fa-spinner fa-spin mr-2"></i>
Loading tickets...
</div>
</div>
</div>
<!-- Verify Ticket -->
<div class="mt-6 bg-white/10 backdrop-blur-lg rounded-2xl p-6 border border-white/20">
<h2 class="text-xl font-bold mb-4 flex items-center">
<i class="fas fa-search text-green-400 mr-2"></i>
Verify Ticket
</h2>
<div class="flex space-x-2">
<input type="text" id="verifyTicket" placeholder="Enter ticket number" 
class="flex-1 bg-black/30 border border-gray-600 rounded-lg px-3 py-2 text-sm text-white focus:outline-none focus:ring-2 focus:ring-green-500">
<button onclick="verifyTicket()" class="bg-green-600 hover:bg-green-700 text-white px-4 py-2 rounded-lg transition">
<i class="fas fa-check"></i>
</button>
</div>
<div id="verificationResult" class="mt-3 text-sm hidden"></div>
</div>
</div>
</div>
<!-- Past Results -->
<div class="mt-12 bg-white/10 backdrop-blur-lg rounded-2xl p-6 border border-white/20">
<h2 class="text-2xl font-bold mb-6 flex items-center">
<i class="fas fa-history text-purple-400 mr-3"></i>
Past Lottery Results
</h2>
<div id="pastResults" class="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-4">
<!-- Results will be loaded here -->
<div class="text-center text-gray-500 py-8 col-span-3">
<i class="fas fa-spinner fa-spin mr-2"></i>
Loading history...
</div>
</div>
</div>
</div>
<!-- Winner Announcement Modal -->
<div id="winnerModal" class="fixed inset-0 bg-black bg-opacity-75 hidden items-center justify-center z-50">
<div class="bg-gradient-to-r from-purple-900 to-indigo-900 rounded-2xl p-8 max-w-md text-center transform scale-0 transition-transform duration-300">
<i class="fas fa-trophy text-6xl text-yellow-400 mb-4"></i>
<h2 class="text-3xl font-bold mb-2">Congratulations!</h2>
<p id="winnerMessage" class="text-xl mb-4"></p>
<button onclick="closeWinnerModal()" class="bg-white text-purple-900 px-6 py-2 rounded-lg font-bold hover:bg-gray-100 transition">
Claim Prize
</button>
</div>
</div>
<script src="script.js"></script>
</body>
</html>

11. `script.js` (Frontend JavaScript)

// script.js
let selectedNumbers = [];
let countdownInterval;
let currentRound = null;
// Load data on page load
document.addEventListener('DOMContentLoaded', function() {
loadLotteryStatus();
loadPastResults();
// Start countdown
countdownInterval = setInterval(updateCountdown, 1000);
// Refresh status every 30 seconds
setInterval(loadLotteryStatus, 30000);
});
// Toggle number selection
function toggleNumber(num) {
const index = selectedNumbers.indexOf(num);
if (index === -1) {
if (selectedNumbers.length >= 6) {
showNotification('You can only select 6 numbers', 'error');
return;
}
selectedNumbers.push(num);
} else {
selectedNumbers.splice(index, 1);
}
// Update UI
updateNumberDisplay();
updateSelectedNumbersDisplay();
}
// Update number ball display
function updateNumberDisplay() {
document.querySelectorAll('.number-ball').forEach(ball => {
const num = parseInt(ball.textContent);
if (selectedNumbers.includes(num)) {
ball.classList.add('selected');
} else {
ball.classList.remove('selected');
}
});
}
// Update selected numbers display
function updateSelectedNumbersDisplay() {
const container = document.getElementById('selectedNumbers');
if (selectedNumbers.length === 0) {
container.innerHTML = '<span class="text-gray-500">None selected</span>';
return;
}
let html = '';
selectedNumbers.sort((a, b) => a - b).forEach(num => {
html += `<span class="number-ball !w-10 !h-10 !text-sm">${num}</span>`;
});
container.innerHTML = html;
}
// Random number selection
function randomNumbers() {
selectedNumbers = [];
while (selectedNumbers.length < 6) {
const num = Math.floor(Math.random() * 49) + 1;
if (!selectedNumbers.includes(num)) {
selectedNumbers.push(num);
}
}
updateNumberDisplay();
updateSelectedNumbersDisplay();
}
// Clear selection
function clearNumbers() {
selectedNumbers = [];
updateNumberDisplay();
updateSelectedNumbersDisplay();
}
// Buy ticket
async function buyTicket() {
if (selectedNumbers.length !== 6) {
showNotification('Please select 6 numbers', 'error');
return;
}
const buyerName = document.getElementById('buyerName').value;
if (!buyerName) {
showNotification('Please enter your name', 'error');
return;
}
const numbers = selectedNumbers.sort((a, b) => a - b).join(',');
const email = document.getElementById('buyerEmail').value;
const formData = {
buyer_name: buyerName,
buyer_email: email,
numbers: numbers
};
try {
const response = await fetch('api/buy_ticket.php', {
method: 'POST',
headers: {
'Content-Type': 'application/json'
},
body: JSON.stringify(formData)
});
const data = await response.json();
if (data.success) {
showNotification(data.message, 'success');
clearNumbers();
document.getElementById('buyerName').value = '';
document.getElementById('buyerEmail').value = '';
loadLotteryStatus();
// Show ticket details
alert(`Your ticket number: ${data.ticket.ticket_number}\nHash: ${data.ticket.hash.substring(0, 20)}...`);
} else {
showNotification('Error: ' + data.message, 'error');
}
} catch (error) {
console.error('Error:', error);
showNotification('Failed to purchase ticket', 'error');
}
}
// Load lottery status
async function loadLotteryStatus() {
try {
const response = await fetch('api/get_lottery_status.php');
const data = await response.json();
if (data.success && data.active) {
currentRound = data;
document.getElementById('jackpotAmount').textContent = data.jackpot.toFixed(2);
document.getElementById('ticketsSold').textContent = data.tickets_sold;
document.getElementById('roundNumber').textContent = data.round;
document.getElementById('drawTime').textContent = data.end_time;
// Update recent tickets
displayRecentTickets(data.recent_tickets);
}
} catch (error) {
console.error('Error loading status:', error);
}
}
// Display recent tickets
function displayRecentTickets(tickets) {
const container = document.getElementById('recentTickets');
if (!tickets || tickets.length === 0) {
container.innerHTML = '<div class="text-center text-gray-500 py-4">No tickets yet</div>';
return;
}
let html = '';
tickets.forEach(ticket => {
html += `
<div class="ticket-card p-3 rounded-lg">
<div class="flex justify-between items-start">
<div>
<p class="font-mono text-xs text-purple-400">${ticket.ticket_number}</p>
<p class="text-sm">${ticket.buyer_name}</p>
</div>
<span class="text-xs text-gray-400">${ticket.time}</span>
</div>
</div>
`;
});
container.innerHTML = html;
}
// Update countdown
function updateCountdown() {
if (!currentRound) return;
const timeRemaining = currentRound.time_remaining;
if (timeRemaining <= 0) {
document.getElementById('countdown').textContent = 'DRAWING...';
document.getElementById('timeRemaining').textContent = 'Drawing soon';
return;
}
const hours = Math.floor(timeRemaining / 3600);
const minutes = Math.floor((timeRemaining % 3600) / 60);
const seconds = timeRemaining % 60;
document.getElementById('countdown').textContent = 
`${hours.toString().padStart(2, '0')}:${minutes.toString().padStart(2, '0')}:${seconds.toString().padStart(2, '0')}`;
document.getElementById('timeRemaining').textContent = 
`${hours}h ${minutes}m ${seconds}s`;
}
// Load past results
async function loadPastResults() {
try {
const response = await fetch('api/get_history.php?limit=6');
const data = await response.json();
if (data.success) {
displayPastResults(data.history);
}
} catch (error) {
console.error('Error loading history:', error);
}
}
// Display past results
function displayPastResults(results) {
const container = document.getElementById('pastResults');
if (!results || results.length === 0) {
container.innerHTML = '<div class="text-center text-gray-500 py-8 col-span-3">No past results</div>';
return;
}
let html = '';
results.forEach(result => {
const winningNumbers = result.winning_numbers ? result.winning_numbers.split(',') : [];
html += `
<div class="ticket-card p-4 rounded-xl">
<div class="flex justify-between items-center mb-3">
<h3 class="font-bold">Round #${result.round_number}</h3>
<span class="text-xs text-gray-400">${result.formatted_date}</span>
</div>
<div class="mb-3">
<p class="text-sm text-gray-400 mb-2">Winning Numbers</p>
<div class="flex space-x-1">
${winningNumbers.map(num => 
`<span class="number-ball !w-8 !h-8 !text-xs">${num}</span>`
).join('')}
</div>
</div>
<div class="grid grid-cols-2 gap-2 text-sm">
<div>
<span class="text-gray-400">Jackpot:</span>
<span class="text-yellow-400">$${result.jackpot_amount.toFixed(2)}</span>
</div>
<div>
<span class="text-gray-400">Winners:</span>
<span class="text-green-400">${result.winner_count}</span>
</div>
</div>
</div>
`;
});
container.innerHTML = html;
}
// Verify ticket
async function verifyTicket() {
const ticketNumber = document.getElementById('verifyTicket').value;
if (!ticketNumber) {
showNotification('Please enter a ticket number', 'error');
return;
}
try {
const response = await fetch(`api/verify_ticket.php?ticket=${encodeURIComponent(ticketNumber)}`);
const data = await response.json();
const resultDiv = document.getElementById('verificationResult');
resultDiv.classList.remove('hidden');
if (data.success) {
if (data.is_winner) {
resultDiv.className = 'mt-3 p-3 bg-green-600/20 border border-green-500 rounded-lg text-green-400';
resultDiv.innerHTML = `
<div class="flex items-center">
<i class="fas fa-trophy mr-2"></i>
<div>
<p class="font-bold">WINNER!</p>
<p>Matched ${data.matches} numbers</p>
<p class="text-lg font-bold">Prize: $${data.prize_amount.toFixed(2)}</p>
${!data.claimed ? '<button onclick="claimPrize(\'' + ticketNumber + '\')" class="mt-2 bg-green-600 text-white px-3 py-1 rounded text-sm">Claim Prize</button>' : 
'<p class="text-sm text-gray-400">Already claimed</p>'}
</div>
</div>
`;
} else {
resultDiv.className = 'mt-3 p-3 bg-yellow-600/20 border border-yellow-500 rounded-lg text-yellow-400';
resultDiv.innerHTML = `
<div class="flex items-center">
<i class="fas fa-times-circle mr-2"></i>
<div>
<p class="font-bold">Not a winner</p>
<p class="text-sm">Better luck next time!</p>
</div>
</div>
`;
}
} else {
resultDiv.className = 'mt-3 p-3 bg-red-600/20 border border-red-500 rounded-lg text-red-400';
resultDiv.innerHTML = `
<div class="flex items-center">
<i class="fas fa-exclamation-circle mr-2"></i>
<div>
<p class="font-bold">Error</p>
<p class="text-sm">${data.message}</p>
</div>
</div>
`;
}
} catch (error) {
console.error('Error:', error);
showNotification('Verification failed', 'error');
}
}
// Claim prize
async function claimPrize(ticketNumber) {
const claimantName = prompt('Enter your name to claim prize:');
if (!claimantName) return;
try {
const response = await fetch('api/claim_prize.php', {
method: 'POST',
headers: {
'Content-Type': 'application/json'
},
body: JSON.stringify({
ticket_number: ticketNumber,
claimant_name: claimantName
})
});
const data = await response.json();
if (data.success) {
showNotification(`Prize claimed: $${data.amount.toFixed(2)}`, 'success');
verifyTicket(); // Refresh verification
} else {
showNotification('Error: ' + data.message, 'error');
}
} catch (error) {
console.error('Error:', error);
showNotification('Failed to claim prize', 'error');
}
}
// Show winner modal
function showWinnerModal(ticketNumber, amount) {
const modal = document.getElementById('winnerModal');
document.getElementById('winnerMessage').textContent = 
`Ticket ${ticketNumber} won $${amount.toFixed(2)}!`;
modal.classList.remove('hidden');
setTimeout(() => {
modal.querySelector('div').classList.add('scale-100');
}, 10);
}
// Close winner modal
function closeWinnerModal() {
const modal = document.getElementById('winnerModal');
modal.querySelector('div').classList.remove('scale-100');
setTimeout(() => {
modal.classList.add('hidden');
}, 300);
}
// Helper: Show notification
function showNotification(message, type = 'info') {
const notification = document.createElement('div');
notification.className = `fixed top-4 right-4 px-6 py-3 rounded-lg shadow-lg z-50 animate-bounce ${
type === 'success' ? 'bg-green-600' :
type === 'error' ? 'bg-red-600' :
'bg-blue-600'
} text-white`;
notification.textContent = message;
document.body.appendChild(notification);
setTimeout(() => {
notification.remove();
}, 3000);
}
// Helper: Escape HTML
function escapeHtml(text) {
if (!text) return '';
const div = document.createElement('div');
div.textContent = text;
return div.innerHTML;
}

12. `style.css` (Additional Styles)

/* style.css - Additional custom styles */
/* Custom scrollbar for recent tickets */
#recentTickets::-webkit-scrollbar {
width: 6px;
}
#recentTickets::-webkit-scrollbar-track {
background: rgba(255, 255, 255, 0.1);
border-radius: 3px;
}
#recentTickets::-webkit-scrollbar-thumb {
background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
border-radius: 3px;
}
/* Number ball animations */
@keyframes selectPulse {
0%, 100% {
box-shadow: 0 0 10px #667eea;
}
50% {
box-shadow: 0 0 30px #667eea;
}
}
.number-ball.selected {
animation: selectPulse 2s infinite;
}
/* Jackpot counter animation */
@keyframes countUp {
from {
transform: translateY(10px);
opacity: 0;
}
to {
transform: translateY(0);
opacity: 1;
}
}
#jackpotAmount {
animation: countUp 0.5s ease-out;
}
/* Ticket card hover effects */
.ticket-card {
position: relative;
overflow: hidden;
}
.ticket-card::before {
content: '';
position: absolute;
top: -50%;
left: -50%;
width: 200%;
height: 200%;
background: linear-gradient(
45deg,
transparent,
rgba(255, 255, 255, 0.1),
transparent
);
transform: rotate(45deg);
transition: all 0.5s ease;
opacity: 0;
}
.ticket-card:hover::before {
opacity: 1;
transform: rotate(45deg) translate(50%, 50%);
}
/* Countdown timer animation */
@keyframes countdownPulse {
0%, 100% {
opacity: 1;
}
50% {
opacity: 0.5;
}
}
.countdown {
animation: countdownPulse 2s infinite;
}
/* Winner announcement */
.winner-glow {
animation: winnerGlow 2s ease-in-out infinite;
}
@keyframes winnerGlow {
0%, 100% {
box-shadow: 0 0 20px gold;
}
50% {
box-shadow: 0 0 50px gold;
}
}
/* Blockchain verification badge */
.blockchain-verified {
background: linear-gradient(90deg, #10b981, #059669);
padding: 2px 8px;
border-radius: 9999px;
font-size: 0.7rem;
display: inline-flex;
align-items: center;
}
/* Loading spinner */
.lottery-spinner {
border: 4px solid rgba(102, 126, 234, 0.3);
border-radius: 50%;
border-top: 4px solid #667eea;
width: 40px;
height: 40px;
animation: spin 1s linear infinite;
}
@keyframes spin {
0% { transform: rotate(0deg); }
100% { transform: rotate(360deg); }
}

How to Run

Setup Environment:

Ensure XAMPP/WAMP/Laragon is installed with PHP 7.4+ and MySQL
Start Apache and MySQL services

Database Setup:

Open phpMyAdmin (http://localhost/phpmyadmin)
Create database chainlotto_db
Import database/schema.sql

Configure Database:

Update includes/config.php with your database credentials

Set Admin Key:

In api/draw_lottery.php, change the admin key from 'CHANGEME_SECRET_KEY' to a secure value

Setup Cron Job (Optional):

For automated draws, add a cron job to run cron/auto_draw.php every hour:
0 * * * * php /path/to/your/project/cron/auto_draw.php

Place Files:

Create folder decentralized-lottery in web root
Copy all files maintaining the structure

Access Application:

Open browser and navigate to: http://localhost/decentralized-lottery/

Testing the Lottery System

Purchase Tickets:

Select 6 numbers by clicking on number balls
Enter your name
Click "Buy Ticket"
Save your ticket number for verification

Monitor Lottery:

Watch jackpot grow as tickets are sold
See countdown to next draw
View recent ticket purchases

Test Verification:

Enter your ticket number in the verify field
Check if you won (after draw)

Admin Functions:

To trigger a manual draw (for testing):
curl -X POST -d "admin_key=CHANGEME_SECRET_KEY" http://localhost/decentralized-lottery/api/draw_lottery.php

Verify Transparency:

All tickets are recorded with their hashes
Winning numbers are generated from ticket data
Anyone can verify the randomness by checking the seed hash

Security Features

Verifiable Randomness: Winning numbers are derived from all ticket hashes
Immutable Tickets: Each ticket is part of a blockchain
Transparent Process: All draws can be audited
Proof of Work: Prevents spam ticket purchases
Automatic Payouts: Winners can claim directly

Prize Structure

6 numbers (Jackpot): 50% of prize pool
5 numbers: 20% of prize pool
4 numbers: 15% of prize pool
3 numbers: 10% of prize pool
2 numbers: 5% of prize pool

This project demonstrates a fully transparent, verifiable lottery system where trust is replaced by mathematics and blockchain technology. No central authority can manipulate the results, and every aspect is publicly auditable.

Introduction

Features

Project File Structure

Database Setup (MySQL)

Code Implementation

1. `includes/config.php` (Database Configuration)

2. `includes/LotteryChain.php` (Core Blockchain Logic)

3. `api/buy_ticket.php` (Purchase Ticket Endpoint)

4. `api/draw_lottery.php` (Trigger Lottery Draw)

5. `api/get_lottery_status.php` (Get Current Status)

6. `api/get_history.php` (Get Lottery History)

7. `api/verify_ticket.php` (Verify Ticket)

8. `api/claim_prize.php` (Claim Winnings)

9. `cron/auto_draw.php` (Automated Draws)

10. `index.php` (Main Application UI)

11. `script.js` (Frontend JavaScript)

12. `style.css` (Additional Styles)

How to Run

Testing the Lottery System

Security Features

Prize Structure

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Macro Nepal Helper

Introduction

Features

Project File Structure

Database Setup (MySQL)

Code Implementation

1. includes/config.php (Database Configuration)

2. includes/LotteryChain.php (Core Blockchain Logic)

3. api/buy_ticket.php (Purchase Ticket Endpoint)

4. api/draw_lottery.php (Trigger Lottery Draw)

5. api/get_lottery_status.php (Get Current Status)

6. api/get_history.php (Get Lottery History)

7. api/verify_ticket.php (Verify Ticket)

8. api/claim_prize.php (Claim Winnings)

9. cron/auto_draw.php (Automated Draws)

10. index.php (Main Application UI)

11. script.js (Frontend JavaScript)

12. style.css (Additional Styles)

How to Run

Testing the Lottery System

Security Features

Prize Structure

Leave a Reply Cancel reply

Macro Nepal Helper

1. `includes/config.php` (Database Configuration)

2. `includes/LotteryChain.php` (Core Blockchain Logic)

3. `api/buy_ticket.php` (Purchase Ticket Endpoint)

4. `api/draw_lottery.php` (Trigger Lottery Draw)

5. `api/get_lottery_status.php` (Get Current Status)

6. `api/get_history.php` (Get Lottery History)

7. `api/verify_ticket.php` (Verify Ticket)

8. `api/claim_prize.php` (Claim Winnings)

9. `cron/auto_draw.php` (Automated Draws)

10. `index.php` (Main Application UI)

11. `script.js` (Frontend JavaScript)

12. `style.css` (Additional Styles)