<?php
// Session initialization for authentication
if (session_status() === PHP_SESSION_NONE) {
    session_start();
}

// Configuration & Store Setup
define('STORE_NAME', 'APEX STUDIO');
define('PRODUCT_NAME', 'Apex Heavyweight Oversized Tee');
define('PRODUCT_PRICE', 390); // THB
define('SHIPPING_FEE', 50); // THB
define('FREE_SHIPPING_MIN_QTY', 2);

define('TOTAL_STOCK_LIMIT', 350); // Total Campaign Limit
define('INITIAL_ORDER_OFFSET', 284); // Initial reserved count
define('ADMIN_PASSWORD', '1234'); // Admin login password

define('DATA_DIR', __DIR__ . '/data');
define('UPLOADS_DIR', __DIR__ . '/uploads');
define('ORDERS_FILE', DATA_DIR . '/orders.json');
define('CUSTOM_PRODUCTS_FILE', DATA_DIR . '/custom_products.json');
define('DB_FILE', DATA_DIR . '/database.sqlite');

// Database Type: 'sqlite' or 'mysql'
define('DB_TYPE', 'sqlite'); 
define('DB_HOST', '127.0.0.1');
define('DB_NAME', 'apex_studio');
define('DB_USER', 'root');
define('DB_PASS', '');

// Ensure data & upload directories exist
if (!file_exists(DATA_DIR)) {
    mkdir(DATA_DIR, 0777, true);
}
if (!file_exists(UPLOADS_DIR)) {
    mkdir(UPLOADS_DIR, 0777, true);
}
if (!file_exists(UPLOADS_DIR . '/avatars')) {
    mkdir(UPLOADS_DIR . '/avatars', 0777, true);
}
if (!file_exists(UPLOADS_DIR . '/products')) {
    mkdir(UPLOADS_DIR . '/products', 0777, true);
}
if (!file_exists(UPLOADS_DIR . '/slips')) {
    mkdir(UPLOADS_DIR . '/slips', 0777, true);
}

// Ensure orders.json & custom_products.json exist
if (!file_exists(ORDERS_FILE)) {
    file_put_contents(ORDERS_FILE, json_encode([], JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
}
if (!file_exists(CUSTOM_PRODUCTS_FILE)) {
    file_put_contents(CUSTOM_PRODUCTS_FILE, json_encode([], JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
}

// --- SHOPEE MEMBERSHIP TIERS CONFIGURATION ---
$SHOPEE_TIERS = [
    'classic' => [
        'id' => 'classic',
        'name' => 'Classic Member (คลาสสิก)',
        'badge' => 'Shopee Classic',
        'color' => 'from-slate-700 via-slate-800 to-slate-900',
        'border' => 'border-slate-600',
        'textColor' => 'text-slate-300',
        'minSpent' => 0,
        'minOrders' => 0,
        'coinCashback' => 1, // 1%
        'freeShippingVouchers' => 1,
        'discountPercent' => 0,
        'icon' => 'shield',
        'gradientGlow' => 'shadow-slate-500/20',
        'nextTier' => 'silver',
        'nextRequirement' => ['spent' => 1000, 'orders' => 2]
    ],
    'silver' => [
        'id' => 'silver',
        'name' => 'Silver Member (ซิลเวอร์)',
        'badge' => 'Shopee Silver',
        'color' => 'from-slate-400 via-zinc-300 to-slate-500',
        'border' => 'border-slate-400',
        'textColor' => 'text-slate-100',
        'minSpent' => 1000,
        'minOrders' => 2,
        'coinCashback' => 3, // 3%
        'freeShippingVouchers' => 2,
        'discountPercent' => 5,
        'icon' => 'medal',
        'gradientGlow' => 'shadow-slate-300/30',
        'nextTier' => 'gold',
        'nextRequirement' => ['spent' => 3000, 'orders' => 5]
    ],
    'gold' => [
        'id' => 'gold',
        'name' => 'Gold Member (โกลด์ VIP)',
        'badge' => 'Shopee Gold VIP',
        'color' => 'from-amber-400 via-yellow-500 to-amber-600',
        'border' => 'border-amber-400',
        'textColor' => 'text-amber-100',
        'minSpent' => 3000,
        'minOrders' => 5,
        'coinCashback' => 5, // 5%
        'freeShippingVouchers' => 4,
        'discountPercent' => 10,
        'icon' => 'crown',
        'gradientGlow' => 'shadow-amber-500/40',
        'nextTier' => 'platinum',
        'nextRequirement' => ['spent' => 8000, 'orders' => 10]
    ],
    'platinum' => [
        'id' => 'platinum',
        'name' => 'Platinum Member (แพลตตินัม Super VIP)',
        'badge' => 'Shopee Platinum Super VIP',
        'color' => 'from-violet-600 via-purple-600 to-indigo-700',
        'border' => 'border-purple-400',
        'textColor' => 'text-purple-100',
        'minSpent' => 8000,
        'minOrders' => 10,
        'coinCashback' => 10, // 10%
        'freeShippingVouchers' => 8,
        'discountPercent' => 15,
        'icon' => 'sparkles',
        'gradientGlow' => 'shadow-purple-500/50',
        'nextTier' => null,
        'nextRequirement' => null
    ]
];

// --- 7-DAY DAILY CHECK-IN STREAK REWARDS ---
$DAILY_STREAK_REWARDS = [
    1 => ['day' => 1, 'coins' => 5, 'label' => '+5 Coins', 'tag' => 'วันที่ 1'],
    2 => ['day' => 2, 'coins' => 10, 'label' => '+10 Coins', 'tag' => 'วันที่ 2'],
    3 => ['day' => 3, 'coins' => 15, 'label' => '+15 Coins', 'tag' => 'วันที่ 3'],
    4 => ['day' => 4, 'coins' => 20, 'label' => '+20 Coins', 'tag' => 'วันที่ 4'],
    5 => ['day' => 5, 'coins' => 25, 'label' => '+25 Coins', 'tag' => 'วันที่ 5'],
    6 => ['day' => 6, 'coins' => 30, 'label' => '+30 Coins', 'tag' => 'วันที่ 6'],
    7 => ['day' => 7, 'coins' => 50, 'label' => '+50 Coins + กล่องเซอร์ไพรส์ 🎁', 'tag' => 'วันที่ 7 (Super Box)']
];

// --- SHOPEE MISSIONS REWARDS ---
$SHOPEE_MISSIONS = [
    [
        'id' => 'profile_complete',
        'title' => 'ตั้งค่าข้อมูลโปรไฟล์และรูปภาพ',
        'subtitle' => 'กรอกชื่อ เบอร์โทร ที่อยู่ และอัปโหลดรูปประจำตัว',
        'rewardCoins' => 30,
        'icon' => 'user',
        'category' => 'profile'
    ],
    [
        'id' => 'checkin_3days',
        'title' => 'เช็คอินรายวันสะสมครบ 3 วัน',
        'subtitle' => 'เข้ามารับเหรียญ Shopee Coins ต่อเนื่อง 3 วัน',
        'rewardCoins' => 50,
        'icon' => 'calendar',
        'category' => 'checkin'
    ],
    [
        'id' => 'lucky_spin_play',
        'title' => 'หมุนวงล้อเสี่ยงโชค Shopee Rewards',
        'subtitle' => 'เล่น Lucky Wheel ลุ้นรับเหรียญและคูปองฟรี',
        'rewardCoins' => 20,
        'icon' => 'sparkles',
        'category' => 'game'
    ],
    [
        'id' => 'collect_3vouchers',
        'title' => 'เก็บโค้ดส่วนลด 3 โค้ดเข้ากระเป๋า',
        'subtitle' => 'สะสมคูปองส่งฟรีและส่วนลด Shopee Mall',
        'rewardCoins' => 25,
        'icon' => 'tag',
        'category' => 'voucher'
    ],
    [
        'id' => 'first_order',
        'title' => 'สั่งซื้อสินค้าชิ้นแรกในร้าน APEX STUDIO',
        'subtitle' => 'ช้อปสินค้าแฟชั่นสตรีทรับ Coins คืนสูงสุด 10%',
        'rewardCoins' => 100,
        'icon' => 'bag',
        'category' => 'shopping'
    ]
];

// --- AVAILABLE SHOPEE VOUCHERS LIST ---
$AVAILABLE_VOUCHERS = [
    [
        'code' => 'SHOPEEFREE',
        'title' => 'โค้ดส่งฟรี ขั้นต่ำ 0.-',
        'subtitle' => 'ใช้ได้กับทุกสินค้าในร้าน APEX STUDIO ไม่มีขั้นต่ำ',
        'discountType' => 'freeship',
        'discountAmount' => 50,
        'minSpend' => 0,
        'tag' => 'ส่งฟรี',
        'color' => 'bg-emerald-600',
        'icon' => 'truck'
    ],
    [
        'code' => 'MALL10',
        'title' => 'ส่วนลด 10% Shopee Mall',
        'subtitle' => 'ลดสูงสุด 200.- เมื่อซื้อครบ 500.- สิทธิพิเศษ Mall',
        'discountType' => 'percent',
        'discountAmount' => 10,
        'minSpend' => 500,
        'tag' => 'Shopee Mall',
        'color' => 'bg-rose-600',
        'icon' => 'tag'
    ],
    [
        'code' => 'COINBACK20',
        'title' => 'เงินคืน 20% Shopee Coins',
        'subtitle' => 'รับเหรียญคืนสูงสุด 150 Coins เมื่อซื้อครบ 300.-',
        'discountType' => 'coinback',
        'discountAmount' => 20,
        'minSpend' => 300,
        'tag' => 'Coins Cashback',
        'color' => 'bg-amber-600',
        'icon' => 'coins'
    ],
    [
        'code' => 'NEWUSER50',
        'title' => 'ลดทันที 50.- ลูกค้าใหม่',
        'subtitle' => 'ไม่มีขั้นต่ำ สำหรับการสั่งซื้อออเดอร์แรก',
        'discountType' => 'fixed',
        'discountAmount' => 50,
        'minSpend' => 0,
        'tag' => 'สมาชิกใหม่',
        'color' => 'bg-orange-600',
        'icon' => 'sparkles'
    ],
    [
        'code' => 'BDAY100',
        'title' => 'ของขวัญวันเกิด ลดทันที 100.-',
        'subtitle' => 'สำหรับสมาชิก Shopee VIP ในเดือนเกิด (ขั้นต่ำ 400.-)',
        'discountType' => 'fixed',
        'discountAmount' => 100,
        'minSpend' => 400,
        'tag' => 'วันเกิด VIP',
        'color' => 'bg-purple-600',
        'icon' => 'gift'
    ]
];

// --- DATABASE CONNECTION & SETUP ---
function getDbConnection() {
    static $pdo = null;
    if ($pdo !== null) return $pdo;

    try {
        if (DB_TYPE === 'sqlite') {
            $pdo = new PDO('sqlite:' . DB_FILE);
            $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
            $pdo->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
        } else {
            try {
                $rootPdo = new PDO("mysql:host=" . DB_HOST . ";charset=utf8mb4", DB_USER, DB_PASS);
                $rootPdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
                $rootPdo->exec("CREATE DATABASE IF NOT EXISTS `" . DB_NAME . "` CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci");
            } catch (PDOException $e) {
                // Ignore if user has no grant to CREATE DATABASE
            }

            $dsn = "mysql:host=" . DB_HOST . ";dbname=" . DB_NAME . ";charset=utf8mb4";
            $pdo = new PDO($dsn, DB_USER, DB_PASS);
            $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
            $pdo->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
        }
        initDbTables($pdo);
    } catch (PDOException $e) {
        error_log("Database Connection Error: " . $e->getMessage());
        if (DB_TYPE === 'mysql') {
            try {
                $pdo = new PDO('sqlite:' . DB_FILE);
                $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
                $pdo->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
                initDbTables($pdo);
                return $pdo;
            } catch (PDOException $sqle) {
                error_log("Fallback SQLite Error: " . $sqle->getMessage());
            }
        }
        return null;
    }
    return $pdo;
}

function initDbTables($pdo) {
    if (!$pdo) return;
    
    $driver = $pdo->getAttribute(PDO::ATTR_DRIVER_NAME);
    $intPrimary = ($driver === 'sqlite') ? "INTEGER PRIMARY KEY AUTOINCREMENT" : "INT AUTO_INCREMENT PRIMARY KEY";

    // 1. Create Users Table with complete Shopee membership attributes
    $usersSql = "CREATE TABLE IF NOT EXISTS users (
        id $intPrimary,
        username VARCHAR(50) NOT NULL UNIQUE,
        email VARCHAR(100) NOT NULL UNIQUE,
        password_hash VARCHAR(255) NOT NULL,
        full_name VARCHAR(100) NOT NULL,
        phone VARCHAR(20) NOT NULL,
        address TEXT NOT NULL,
        role VARCHAR(20) DEFAULT 'member',
        badge VARCHAR(50) DEFAULT 'Shopee Classic',
        membership_tier VARCHAR(20) DEFAULT 'classic',
        total_spent DECIMAL(10,2) DEFAULT 0,
        orders_count INTEGER DEFAULT 0,
        points INTEGER DEFAULT 100,
        coins INTEGER DEFAULT 100,
        daily_checkin VARCHAR(20) DEFAULT '',
        checkin_streak INTEGER DEFAULT 0,
        last_spin_date VARCHAR(20) DEFAULT '',
        missions_json TEXT DEFAULT '[]',
        vouchers_json TEXT DEFAULT '[]',
        avatar VARCHAR(255) DEFAULT '',
        gender VARCHAR(10) DEFAULT 'other',
        birthday VARCHAR(20) DEFAULT '',
        created_at DATETIME DEFAULT CURRENT_TIMESTAMP
    )";
    $pdo->exec($usersSql);

    // Auto-migrate missing columns
    $missingCols = [
        'membership_tier' => "VARCHAR(20) DEFAULT 'classic'",
        'total_spent' => "DECIMAL(10,2) DEFAULT 0",
        'orders_count' => "INTEGER DEFAULT 0",
        'points' => "INTEGER DEFAULT 100",
        'coins' => "INTEGER DEFAULT 100",
        'daily_checkin' => "VARCHAR(20) DEFAULT ''",
        'checkin_streak' => "INTEGER DEFAULT 0",
        'last_spin_date' => "VARCHAR(20) DEFAULT ''",
        'missions_json' => "TEXT DEFAULT '[]'",
        'vouchers_json' => "TEXT DEFAULT '[]'",
        'avatar' => "VARCHAR(255) DEFAULT ''",
        'gender' => "VARCHAR(10) DEFAULT 'other'",
        'birthday' => "VARCHAR(20) DEFAULT ''"
    ];

    if ($driver === 'sqlite') {
        $cols = [];
        $stmt = $pdo->query("PRAGMA table_info(users)");
        while ($row = $stmt->fetch()) {
            $cols[] = $row['name'];
        }
        foreach ($missingCols as $colName => $colDef) {
            if (!in_array($colName, $cols)) {
                try {
                    $pdo->exec("ALTER TABLE users ADD COLUMN $colName $colDef");
                } catch (Exception $e) {}
            }
        }
    }

    // 2. Create Orders Table
    $ordersSql = "CREATE TABLE IF NOT EXISTS orders (
        id $intPrimary,
        order_id VARCHAR(50) NOT NULL UNIQUE,
        user_id INTEGER NULL,
        customer_name VARCHAR(100) NOT NULL,
        customer_phone VARCHAR(20) NOT NULL,
        customer_address TEXT NOT NULL,
        payment_method VARCHAR(50) NOT NULL,
        subtotal DECIMAL(10,2) NOT NULL,
        shipping DECIMAL(10,2) NOT NULL,
        discount DECIMAL(10,2) DEFAULT 0,
        coins_used INTEGER DEFAULT 0,
        coins_earned INTEGER DEFAULT 0,
        grand_total DECIMAL(10,2) NOT NULL,
        status VARCHAR(50) DEFAULT 'Pending Payment',
        items_json TEXT NOT NULL,
        slip_image VARCHAR(255) DEFAULT '',
        tracking_number VARCHAR(50) DEFAULT '',
        created_at DATETIME DEFAULT CURRENT_TIMESTAMP
    )";
    $pdo->exec($ordersSql);

    // 3. Create Coin Logs Table
    $coinLogsSql = "CREATE TABLE IF NOT EXISTS coin_logs (
        id $intPrimary,
        user_id INTEGER NOT NULL,
        type VARCHAR(30) NOT NULL,
        amount INTEGER NOT NULL,
        balance_after INTEGER NOT NULL,
        order_code VARCHAR(50) DEFAULT NULL,
        description VARCHAR(255) NOT NULL,
        created_at DATETIME DEFAULT CURRENT_TIMESTAMP
    )";
    $pdo->exec($coinLogsSql);

    // Seed default demo accounts if table has fewer than 2 users
    $userCountStmt = $pdo->query("SELECT COUNT(*) FROM users");
    if ($userCountStmt && $userCountStmt->fetchColumn() < 2) {
        seedDemoUsers($pdo);
    }
}

function seedDemoUsers($pdo) {
    $defaultPassHash = password_hash('123456', PASSWORD_BCRYPT);
    $users = [
        [
            'username' => 'admin',
            'email' => 'admin@apexstudio.com',
            'password_hash' => $defaultPassHash,
            'full_name' => 'ผู้ดูแลระบบ APEX STUDIO',
            'phone' => '081-999-8888',
            'address' => 'APEX Studio Flagship Store สยามสแควร์ กรุงเทพมหานคร 10330',
            'role' => 'admin',
            'badge' => 'Shopee Platinum Super VIP',
            'membership_tier' => 'platinum',
            'total_spent' => 15900.00,
            'orders_count' => 18,
            'points' => 1590,
            'coins' => 500,
            'checkin_streak' => 5,
            'vouchers_json' => json_encode(['SHOPEEFREE', 'MALL10', 'COINBACK20', 'NEWUSER50', 'BDAY100'], JSON_UNESCAPED_UNICODE),
            'avatar' => 'https://images.unsplash.com/photo-1534528741775-53994a69daeb?w=400&auto=format&fit=crop&q=80',
            'gender' => 'other',
            'birthday' => '1995-08-17'
        ],
        [
            'username' => 'member_vip',
            'email' => 'vip@apexstudio.com',
            'password_hash' => $defaultPassHash,
            'full_name' => 'คุณพงศกร สมาชิกแพลตตินัม (Platinum VIP)',
            'phone' => '089-123-4567',
            'address' => '88/12 อาคารสยามทาวเวอร์ แขวงปทุมวัน เขตปทุมวัน กรุงเทพมหานคร 10330',
            'role' => 'member',
            'badge' => 'Shopee Platinum Super VIP',
            'membership_tier' => 'platinum',
            'total_spent' => 9450.00,
            'orders_count' => 12,
            'points' => 945,
            'coins' => 350,
            'checkin_streak' => 4,
            'vouchers_json' => json_encode(['SHOPEEFREE', 'MALL10', 'COINBACK20', 'BDAY100'], JSON_UNESCAPED_UNICODE),
            'avatar' => 'https://images.unsplash.com/photo-1539571696357-5a69c17a67c6?w=400&auto=format&fit=crop&q=80',
            'gender' => 'male',
            'birthday' => '1998-05-15'
        ],
        [
            'username' => 'somchai',
            'email' => 'somchai@gmail.com',
            'password_hash' => $defaultPassHash,
            'full_name' => 'สมชาย สายสตรีท (Gold VIP)',
            'phone' => '086-555-1234',
            'address' => '123/45 ถนนสุขุมวิท แขวงคลองเตย เขตคลองเตย กรุงเทพมหานคร 10110',
            'role' => 'member',
            'badge' => 'Shopee Gold VIP',
            'membership_tier' => 'gold',
            'total_spent' => 3890.00,
            'orders_count' => 6,
            'points' => 389,
            'coins' => 180,
            'checkin_streak' => 2,
            'vouchers_json' => json_encode(['SHOPEEFREE', 'MALL10', 'NEWUSER50'], JSON_UNESCAPED_UNICODE),
            'avatar' => 'https://images.unsplash.com/photo-1507003211169-0a1dd7228f2d?w=400&auto=format&fit=crop&q=80',
            'gender' => 'male',
            'birthday' => '2000-08-20'
        ],
        [
            'username' => 'nicha',
            'email' => 'nicha@gmail.com',
            'password_hash' => $defaultPassHash,
            'full_name' => 'ณิชา แฟชั่นนิสต้า (Silver)',
            'phone' => '081-444-9988',
            'address' => '55/9 ถนนพหลโยธิน แขวงจตุจักร เขตจตุจักร กรุงเทพมหานคร 10900',
            'role' => 'member',
            'badge' => 'Shopee Silver',
            'membership_tier' => 'silver',
            'total_spent' => 1490.00,
            'orders_count' => 2,
            'points' => 149,
            'coins' => 120,
            'checkin_streak' => 1,
            'vouchers_json' => json_encode(['SHOPEEFREE', 'NEWUSER50'], JSON_UNESCAPED_UNICODE),
            'avatar' => 'https://images.unsplash.com/photo-1494790108377-be9c29b29330?w=400&auto=format&fit=crop&q=80',
            'gender' => 'female',
            'birthday' => '2001-11-10'
        ],
        [
            'username' => 'new_user',
            'email' => 'newuser@gmail.com',
            'password_hash' => $defaultPassHash,
            'full_name' => 'สมาชิกใหม่ Shopee Classic',
            'phone' => '089-777-6655',
            'address' => '99/1 ซอยอารีย์ แขวงสามเสนใน เขตพญาไท กรุงเทพมหานคร 10400',
            'role' => 'member',
            'badge' => 'Shopee Classic',
            'membership_tier' => 'classic',
            'total_spent' => 0.00,
            'orders_count' => 0,
            'points' => 100,
            'coins' => 100,
            'checkin_streak' => 0,
            'vouchers_json' => json_encode(['SHOPEEFREE', 'NEWUSER50'], JSON_UNESCAPED_UNICODE),
            'avatar' => 'https://images.unsplash.com/photo-1535713875002-d1d0cf377fde?w=400&auto=format&fit=crop&q=80',
            'gender' => 'other',
            'birthday' => '2002-03-25'
        ]
    ];

    foreach ($users as $u) {
        try {
            $stmt = $pdo->prepare("INSERT INTO users (username, email, password_hash, full_name, phone, address, role, badge, membership_tier, total_spent, orders_count, points, coins, checkin_streak, vouchers_json, avatar, gender, birthday) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)");
            $stmt->execute([
                $u['username'],
                $u['email'],
                $u['password_hash'],
                $u['full_name'],
                $u['phone'],
                $u['address'],
                $u['role'],
                $u['badge'],
                $u['membership_tier'],
                $u['total_spent'],
                $u['orders_count'],
                $u['points'],
                $u['coins'],
                $u['checkin_streak'],
                $u['vouchers_json'],
                $u['avatar'],
                $u['gender'],
                $u['birthday']
            ]);
            $insertedId = $pdo->lastInsertId();
            logCoinTransaction($insertedId, 'welcome_bonus', $u['coins'], $u['coins'], null, 'โบนัสต้อนรับสมาชิกใหม่ Shopee Member Club');
        } catch (Exception $e) {}
    }
}

// Ensure DB is initialized
getDbConnection();

// --- COIN TRANSACTION LOGGER ---
function logCoinTransaction($userId, $type, $amount, $balanceAfter, $orderCode = null, $description = '') {
    $pdo = getDbConnection();
    if (!$pdo) return false;
    try {
        $stmt = $pdo->prepare("INSERT INTO coin_logs (user_id, type, amount, balance_after, order_code, description) VALUES (?, ?, ?, ?, ?, ?)");
        return $stmt->execute([$userId, $type, $amount, $balanceAfter, $orderCode, $description]);
    } catch (Exception $e) {
        return false;
    }
}

function getCoinLogs($userId, $limit = 20) {
    $pdo = getDbConnection();
    if (!$pdo) return [];
    try {
        $stmt = $pdo->prepare("SELECT * FROM coin_logs WHERE user_id = ? ORDER BY id DESC LIMIT ?");
        $stmt->bindValue(1, $userId, PDO::PARAM_INT);
        $stmt->bindValue(2, $limit, PDO::PARAM_INT);
        $stmt->execute();
        return $stmt->fetchAll();
    } catch (Exception $e) {
        return [];
    }
}

// --- TIER CALCULATION HELPER ---
function calculateMembershipTier($totalSpent, $ordersCount) {
    global $SHOPEE_TIERS;
    if ($totalSpent >= 8000 || $ordersCount >= 10) return 'platinum';
    if ($totalSpent >= 3000 || $ordersCount >= 5) return 'gold';
    if ($totalSpent >= 1000 || $ordersCount >= 2) return 'silver';
    return 'classic';
}

function formatUserData($user) {
    global $SHOPEE_TIERS;
    if (!$user) return null;
    unset($user['password_hash']);

    $totalSpent = floatval($user['total_spent'] ?? 0);
    $ordersCount = intval($user['orders_count'] ?? 0);
    $tierKey = calculateMembershipTier($totalSpent, $ordersCount);
    $tierInfo = $SHOPEE_TIERS[$tierKey] ?? $SHOPEE_TIERS['classic'];

    $user['membership_tier'] = $tierKey;
    $user['tier_info'] = $tierInfo;
    $user['badge'] = $tierInfo['badge'];
    $user['coins'] = intval($user['coins'] ?? 100);
    $user['checkin_streak'] = intval($user['checkin_streak'] ?? 0);
    $user['total_spent'] = $totalSpent;
    $user['orders_count'] = $ordersCount;
    $user['missions_completed'] = json_decode($user['missions_json'] ?? '[]', true) ?: [];
    $user['vouchers'] = json_decode($user['vouchers_json'] ?? '[]', true) ?: ['SHOPEEFREE', 'NEWUSER50'];
    $user['avatar'] = $user['avatar'] ?? '';
    
    return $user;
}

// --- 7-DAY STREAK DAILY CHECK-IN ---
function claimDailyCoinsWithStreak($userId) {
    global $DAILY_STREAK_REWARDS;
    $pdo = getDbConnection();
    if (!$pdo) return ['success' => false, 'message' => 'Database error'];

    $today = date('Y-m-d');
    $yesterday = date('Y-m-d', strtotime('-1 day'));

    $stmt = $pdo->prepare("SELECT daily_checkin, checkin_streak, coins FROM users WHERE id = ?");
    $stmt->execute([$userId]);
    $u = $stmt->fetch();
    if (!$u) return ['success' => false, 'message' => 'User not found'];

    if ($u['daily_checkin'] === $today) {
        return ['success' => false, 'message' => 'คุณได้กดรับเหรียญประจำวันนี้ไปแล้ว เจอกันใหม่พรุ่งนี้นะ!'];
    }

    $currentStreak = intval($u['checkin_streak'] ?? 0);
    if ($u['daily_checkin'] === $yesterday) {
        $newStreak = ($currentStreak % 7) + 1;
    } else {
        $newStreak = 1;
    }

    $rewardInfo = $DAILY_STREAK_REWARDS[$newStreak] ?? $DAILY_STREAK_REWARDS[1];
    $coinsReward = $rewardInfo['coins'];
    $newCoins = intval($u['coins'] ?? 0) + $coinsReward;

    $stmtUp = $pdo->prepare("UPDATE users SET daily_checkin = ?, checkin_streak = ?, coins = ? WHERE id = ?");
    $stmtUp->execute([$today, $newStreak, $newCoins, $userId]);

    logCoinTransaction($userId, 'daily_checkin', $coinsReward, $newCoins, null, "เช็คอินวันที่ {$newStreak} (+{$coinsReward} Coins)");

    $stmtFresh = $pdo->prepare("SELECT * FROM users WHERE id = ?");
    $stmtFresh->execute([$userId]);
    $updatedUser = formatUserData($stmtFresh->fetch());
    $_SESSION['user'] = $updatedUser;

    return [
        'success' => true,
        'message' => "เช็คอินสำเร็จ! คุณได้รับ +{$coinsReward} Shopee Coins (สะสมวันที่ {$newStreak}/7)",
        'user' => $updatedUser,
        'earnedCoins' => $coinsReward,
        'streak' => $newStreak,
        'rewardInfo' => $rewardInfo
    ];
}

// --- SHOPEE LUCKY SPIN WHEEL ---
function spinLuckyWheel($userId) {
    $pdo = getDbConnection();
    if (!$pdo) return ['success' => false, 'message' => 'Database error'];

    $today = date('Y-m-d');
    $stmt = $pdo->prepare("SELECT last_spin_date, coins, vouchers_json FROM users WHERE id = ?");
    $stmt->execute([$userId]);
    $u = $stmt->fetch();
    if (!$u) return ['success' => false, 'message' => 'User not found'];

    // Possible prizes
    $prizes = [
        ['id' => 1, 'name' => '10 Shopee Coins', 'type' => 'coins', 'amount' => 10, 'icon' => '🪙', 'color' => '#f59e0b'],
        ['id' => 2, 'name' => '20 Shopee Coins', 'type' => 'coins', 'amount' => 20, 'icon' => '🪙', 'color' => '#d97706'],
        ['id' => 3, 'name' => 'โค้ดส่งฟรี 0.-', 'type' => 'voucher', 'voucherCode' => 'SHOPEEFREE', 'amount' => 0, 'icon' => '🚚', 'color' => '#10b981'],
        ['id' => 4, 'name' => '50 Shopee Coins', 'type' => 'coins', 'amount' => 50, 'icon' => '✨', 'color' => '#ea580c'],
        ['id' => 5, 'name' => 'ส่วนลด 10% Mall', 'type' => 'voucher', 'voucherCode' => 'MALL10', 'amount' => 0, 'icon' => '🏷️', 'color' => '#e11d48'],
        ['id' => 6, 'name' => '100 Shopee Coins (BIG WIN!)', 'type' => 'coins', 'amount' => 100, 'icon' => '👑', 'color' => '#8b5cf6']
    ];

    $wonPrize = $prizes[array_rand($prizes)];

    $newCoins = intval($u['coins'] ?? 0);
    $vouchers = json_decode($u['vouchers_json'] ?? '[]', true) ?: [];

    if ($wonPrize['type'] === 'coins') {
        $newCoins += $wonPrize['amount'];
        logCoinTransaction($userId, 'lucky_spin', $wonPrize['amount'], $newCoins, null, "รางวัลจาก Lucky Spin: +{$wonPrize['amount']} Coins");
    } elseif ($wonPrize['type'] === 'voucher' && !in_array($wonPrize['voucherCode'], $vouchers)) {
        $vouchers[] = $wonPrize['voucherCode'];
    }

    $stmtUp = $pdo->prepare("UPDATE users SET last_spin_date = ?, coins = ?, vouchers_json = ? WHERE id = ?");
    $stmtUp->execute([$today, $newCoins, json_encode($vouchers, JSON_UNESCAPED_UNICODE), $userId]);

    $stmtFresh = $pdo->prepare("SELECT * FROM users WHERE id = ?");
    $stmtFresh->execute([$userId]);
    $updatedUser = formatUserData($stmtFresh->fetch());
    $_SESSION['user'] = $updatedUser;

    return [
        'success' => true,
        'message' => "ยินดีด้วย! คุณได้รับรางวัล: {$wonPrize['name']} 🎉",
        'prize' => $wonPrize,
        'user' => $updatedUser
    ];
}

// --- CLAIM MISSION REWARD ---
function claimMissionReward($userId, $missionId) {
    global $SHOPEE_MISSIONS;
    $pdo = getDbConnection();
    if (!$pdo) return ['success' => false, 'message' => 'Database error'];

    $targetMission = null;
    foreach ($SHOPEE_MISSIONS as $m) {
        if ($m['id'] === $missionId) {
            $targetMission = $m;
            break;
        }
    }
    if (!$targetMission) return ['success' => false, 'message' => 'ไม่พบภารกิจนี้'];

    $stmt = $pdo->prepare("SELECT missions_json, coins FROM users WHERE id = ?");
    $stmt->execute([$userId]);
    $u = $stmt->fetch();
    if (!$u) return ['success' => false, 'message' => 'User not found'];

    $completedMissions = json_decode($u['missions_json'] ?? '[]', true) ?: [];
    if (in_array($missionId, $completedMissions)) {
        return ['success' => false, 'message' => 'คุณเคยกดรับรางวัลภารกิจนี้ไปแล้ว'];
    }

    $rewardCoins = $targetMission['rewardCoins'];
    $newCoins = intval($u['coins'] ?? 0) + $rewardCoins;
    $completedMissions[] = $missionId;

    $stmtUp = $pdo->prepare("UPDATE users SET missions_json = ?, coins = ? WHERE id = ?");
    $stmtUp->execute([json_encode($completedMissions, JSON_UNESCAPED_UNICODE), $newCoins, $userId]);

    logCoinTransaction($userId, 'mission_reward', $rewardCoins, $newCoins, null, "รางวัลภารกิจ: {$targetMission['title']} (+{$rewardCoins} Coins)");

    $stmtFresh = $pdo->prepare("SELECT * FROM users WHERE id = ?");
    $stmtFresh->execute([$userId]);
    $updatedUser = formatUserData($stmtFresh->fetch());
    $_SESSION['user'] = $updatedUser;

    return [
        'success' => true,
        'message' => "สำเร็จ! คุณได้รับ +{$rewardCoins} Shopee Coins จากภารกิจ '{$targetMission['title']}' 🎉",
        'user' => $updatedUser,
        'earnedCoins' => $rewardCoins
    ];
}

// --- QUICK DEMO LOGIN AS TIER ---
function quickLoginAsTier($tierKey) {
    $pdo = getDbConnection();
    if (!$pdo) return ['success' => false, 'message' => 'Database error'];

    $map = [
        'platinum' => 'member_vip',
        'gold' => 'somchai',
        'silver' => 'nicha',
        'classic' => 'new_user',
        'admin' => 'admin'
    ];

    $targetUsername = $map[$tierKey] ?? 'new_user';
    $stmt = $pdo->prepare("SELECT * FROM users WHERE username = ?");
    $stmt->execute([$targetUsername]);
    $rawUser = $stmt->fetch();

    if ($rawUser) {
        $user = formatUserData($rawUser);
        $_SESSION['user'] = $user;
        return [
            'success' => true,
            'message' => "สลับเข้าใช้งานในฐานะ {$user['full_name']} ({$user['badge']}) สำเร็จ!",
            'user' => $user
        ];
    }

    return ['success' => false, 'message' => 'ไม่พบบัญชีทดสอบ'];
}

// --- MEMBER / AUTHENTICATION FUNCTIONS ---
function registerUser($username, $email, $password, $fullName, $phone, $address) {
    $pdo = getDbConnection();
    if (!$pdo) {
        return ['success' => false, 'message' => 'ไม่สามารถเชื่อมต่อฐานข้อมูลได้'];
    }

    $username = trim($username);
    $email = trim(strtolower($email));
    $fullName = trim($fullName);
    $phone = trim($phone);
    $address = trim($address);

    if (empty($username) || empty($email) || empty($password) || empty($fullName) || empty($phone)) {
        return ['success' => false, 'message' => 'กรุณากรอกข้อมูลให้ครบถ้วนทุกช่อง'];
    }

    if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
        return ['success' => false, 'message' => 'รูปแบบอีเมลไม่ถูกต้อง'];
    }

    if (strlen($password) < 6) {
        return ['success' => false, 'message' => 'รหัสผ่านต้องมีความยาวอย่างน้อย 6 ตัวอักษร'];
    }

    // Check if username or email exists
    $stmt = $pdo->prepare("SELECT id FROM users WHERE username = ? OR email = ?");
    $stmt->execute([$username, $email]);
    if ($stmt->fetch()) {
        return ['success' => false, 'message' => 'ชื่อผู้ใช้หรืออีเมลนี้มีอยู่ในระบบแล้ว'];
    }

    $passwordHash = password_hash($password, PASSWORD_BCRYPT);
    $initialVouchers = json_encode(['SHOPEEFREE', 'NEWUSER50', 'MALL10'], JSON_UNESCAPED_UNICODE);
    
    $stmt = $pdo->prepare("INSERT INTO users (username, email, password_hash, full_name, phone, address, role, badge, membership_tier, total_spent, orders_count, coins, points, vouchers_json, avatar) VALUES (?, ?, ?, ?, ?, ?, 'member', 'Shopee Classic', 'classic', 0, 0, 100, 100, ?, '')");
    
    if ($stmt->execute([$username, $email, $passwordHash, $fullName, $phone, $address, $initialVouchers])) {
        $userId = $pdo->lastInsertId();
        logCoinTransaction($userId, 'welcome_bonus', 100, 100, null, 'โบนัสต้อนรับสมาชิกใหม่ Shopee Member Club');

        $stmtUser = $pdo->prepare("SELECT * FROM users WHERE id = ?");
        $stmtUser->execute([$userId]);
        $userData = formatUserData($stmtUser->fetch());
        $_SESSION['user'] = $userData;
        return ['success' => true, 'message' => 'สมัครสมาชิก Shopee Member Club สำเร็จ! รับฟรี 100 Shopee Coins & คูปองต้อนรับ', 'user' => $userData];
    }

    return ['success' => false, 'message' => 'เกิดข้อผิดพลาดในการบันทึกข้อมูลสมาชิก'];
}

function loginUser($usernameOrEmail, $password) {
    $pdo = getDbConnection();
    if (!$pdo) {
        return ['success' => false, 'message' => 'ไม่สามารถเชื่อมต่อฐานข้อมูลได้'];
    }

    $input = trim($usernameOrEmail);
    if (empty($input) || empty($password)) {
        return ['success' => false, 'message' => 'กรุณากรอกชื่อผู้ใช้/อีเมล และรหัสผ่าน'];
    }

    $stmt = $pdo->prepare("SELECT * FROM users WHERE username = ? OR email = ?");
    $stmt->execute([$input, strtolower($input)]);
    $rawUser = $stmt->fetch();

    if ($rawUser && password_verify($password, $rawUser['password_hash'])) {
        $user = formatUserData($rawUser);
        $_SESSION['user'] = $user;
        return ['success' => true, 'message' => 'เข้าสู่ระบบ Shopee Member Club สำเร็จ! ยินดีต้อนรับ ' . $user['full_name'], 'user' => $user];
    }

    return ['success' => false, 'message' => 'ชื่อผู้ใช้/อีเมล หรือรหัสผ่านไม่ถูกต้อง'];
}

function getLoggedInUser() {
    if (!isset($_SESSION['user']) || empty($_SESSION['user']['id'])) {
        return null;
    }
    $pdo = getDbConnection();
    if ($pdo) {
        $stmt = $pdo->prepare("SELECT * FROM users WHERE id = ?");
        $stmt->execute([$_SESSION['user']['id']]);
        $fresh = $stmt->fetch();
        if ($fresh) {
            $_SESSION['user'] = formatUserData($fresh);
        }
    }
    return $_SESSION['user'] ?? null;
}

function collectVoucher($userId, $voucherCode) {
    $pdo = getDbConnection();
    if (!$pdo) return ['success' => false, 'message' => 'Database error'];

    $stmt = $pdo->prepare("SELECT vouchers_json FROM users WHERE id = ?");
    $stmt->execute([$userId]);
    $u = $stmt->fetch();
    if (!$u) return ['success' => false, 'message' => 'User not found'];

    $vouchers = json_decode($u['vouchers_json'] ?? '[]', true) ?: [];
    if (in_array($voucherCode, $vouchers)) {
        return ['success' => false, 'message' => 'คุณเก็บโค้ดนี้ไปแล้วในกระเป๋าคูปอง'];
    }

    $vouchers[] = $voucherCode;
    $stmtUp = $pdo->prepare("UPDATE users SET vouchers_json = ? WHERE id = ?");
    $stmtUp->execute([json_encode($vouchers, JSON_UNESCAPED_UNICODE), $userId]);

    $stmtFresh = $pdo->prepare("SELECT * FROM users WHERE id = ?");
    $stmtFresh->execute([$userId]);
    $updatedUser = formatUserData($stmtFresh->fetch());
    $_SESSION['user'] = $updatedUser;

    return ['success' => true, 'message' => 'เก็บโค้ดส่วนลดเข้ากระเป๋าเรียบร้อยแล้ว!', 'user' => $updatedUser];
}

function getUserOrdersFromDb($userId) {
    $pdo = getDbConnection();
    if (!$pdo) return [];

    $stmt = $pdo->prepare("SELECT * FROM orders WHERE user_id = ? ORDER BY id DESC");
    $stmt->execute([$userId]);
    $rows = $stmt->fetchAll();

    $result = [];
    foreach ($rows as $row) {
        $result[] = [
            'orderId' => $row['order_id'],
            'customer' => [
                'fullName' => $row['customer_name'],
                'phone' => $row['customer_phone'],
                'address' => $row['customer_address'],
                'paymentMethod' => $row['payment_method']
            ],
            'subtotal' => floatval($row['subtotal']),
            'shipping' => floatval($row['shipping']),
            'discount' => floatval($row['discount'] ?? 0),
            'coinsUsed' => intval($row['coins_used'] ?? 0),
            'coinsEarned' => intval($row['coins_earned'] ?? 0),
            'grandTotal' => floatval($row['grand_total']),
            'status' => $row['status'],
            'slipImage' => $row['slip_image'] ?? '',
            'trackingNumber' => $row['tracking_number'] ?? '',
            'createdAt' => $row['created_at'],
            'items' => json_decode($row['items_json'], true) ?: []
        ];
    }
    return $result;
}

function saveOrderToDb($newOrder, $userId = null) {
    $pdo = getDbConnection();
    if (!$pdo) return false;

    try {
        $stmt = $pdo->prepare("INSERT INTO orders (order_id, user_id, customer_name, customer_phone, customer_address, payment_method, subtotal, shipping, discount, coins_used, coins_earned, grand_total, status, items_json, slip_image) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)");
        $stmt->execute([
            $newOrder['orderId'],
            $userId,
            $newOrder['customer']['fullName'] ?? '',
            $newOrder['customer']['phone'] ?? '',
            $newOrder['customer']['address'] ?? '',
            $newOrder['customer']['paymentMethod'] ?? 'promptpay',
            $newOrder['subtotal'] ?? 0,
            $newOrder['shipping'] ?? 0,
            $newOrder['discount'] ?? 0,
            $newOrder['coinsUsed'] ?? 0,
            $newOrder['coinsEarned'] ?? 0,
            $newOrder['grandTotal'] ?? 0,
            $newOrder['status'] ?? 'Pending Payment',
            json_encode($newOrder['items'] ?? [], JSON_UNESCAPED_UNICODE),
            $newOrder['slipImage'] ?? ''
        ]);

        // If logged in user, update user spending & tier & deduct coins used & add coins earned
        if ($userId) {
            $stmtUser = $pdo->prepare("SELECT total_spent, orders_count, coins FROM users WHERE id = ?");
            $stmtUser->execute([$userId]);
            $u = $stmtUser->fetch();
            if ($u) {
                $newSpent = floatval($u['total_spent'] ?? 0) + floatval($newOrder['grandTotal']);
                $newOrdersCount = intval($u['orders_count'] ?? 0) + 1;
                $newCoins = max(0, intval($u['coins'] ?? 0) - intval($newOrder['coinsUsed'] ?? 0)) + intval($newOrder['coinsEarned'] ?? 0);
                $newTier = calculateMembershipTier($newSpent, $newOrdersCount);

                $stmtUp = $pdo->prepare("UPDATE users SET total_spent = ?, orders_count = ?, coins = ?, membership_tier = ? WHERE id = ?");
                $stmtUp->execute([$newSpent, $newOrdersCount, $newCoins, $newTier, $userId]);

                if (intval($newOrder['coinsUsed'] ?? 0) > 0) {
                    logCoinTransaction($userId, 'spend', -intval($newOrder['coinsUsed']), $newCoins - intval($newOrder['coinsEarned'] ?? 0), $newOrder['orderId'], "ใช้เหรียญเป็นส่วนลดออเดอร์ {$newOrder['orderId']}");
                }
                if (intval($newOrder['coinsEarned'] ?? 0) > 0) {
                    logCoinTransaction($userId, 'earn', intval($newOrder['coinsEarned']), $newCoins, $newOrder['orderId'], "เงินคืน Shopee Coins จากออเดอร์ {$newOrder['orderId']}");
                }
            }
        }
        return true;
    } catch (PDOException $e) {
        error_log("Failed to save order to DB: " . $e->getMessage());
        return false;
    }
}

// Colors configuration for SVG T-shirt customizer
$COLOR_OPTIONS = [
    [
        'id' => 'black',
        'name' => 'Classic Black (ดำคลาสสิก)',
        'hex' => '#18181b',
        'collarHex' => '#09090b',
        'textDark' => false,
        'printColor' => '#f8fafc',
        'accentColor' => '#10b981',
        'shadow' => 'rgba(0,0,0,0.6)',
        'tag' => 'Popular'
    ],
    [
        'id' => 'off-white',
        'name' => 'Off-White Cream (ขาวครีม)',
        'hex' => '#f5f5f4',
        'collarHex' => '#e7e5e4',
        'textDark' => true,
        'printColor' => '#0f172a',
        'accentColor' => '#059669',
        'shadow' => 'rgba(0,0,0,0.15)',
        'tag' => 'Trending'
    ],
    [
        'id' => 'navy',
        'name' => 'Navy Blue (น้ำเงินกรมท่า)',
        'hex' => '#1e293b',
        'collarHex' => '#0f172a',
        'textDark' => false,
        'printColor' => '#38bdf8',
        'accentColor' => '#38bdf8',
        'shadow' => 'rgba(15,23,42,0.6)',
        'tag' => ''
    ],
    [
        'id' => 'olive',
        'name' => 'Olive Green (เขียวออลีฟ)',
        'hex' => '#3f6212',
        'collarHex' => '#1a2e05',
        'textDark' => false,
        'printColor' => '#fef08a',
        'accentColor' => '#eab308',
        'shadow' => 'rgba(26,46,5,0.6)',
        'tag' => 'Limited'
    ],
    [
        'id' => 'crimson',
        'name' => 'Vintage Crimson (แดงไวน์)',
        'hex' => '#881337',
        'collarHex' => '#4c0519',
        'textDark' => false,
        'printColor' => '#fecdd3',
        'accentColor' => '#fb7185',
        'shadow' => 'rgba(76,5,25,0.6)',
        'tag' => ''
    ],
    [
        'id' => 'slate',
        'name' => 'Slate Gray (เทาสเลท)',
        'hex' => '#475569',
        'collarHex' => '#334155',
        'textDark' => false,
        'printColor' => '#e2e8f0',
        'accentColor' => '#818cf8',
        'shadow' => 'rgba(51,65,85,0.6)',
        'tag' => ''
    ]
];

// Sizes configuration
$SIZE_OPTIONS = [
    ['id' => 'S', 'label' => 'S', 'chest' => 38, 'length' => 27, 'shoulder' => 19],
    ['id' => 'M', 'label' => 'M', 'chest' => 40, 'length' => 28, 'shoulder' => 20],
    ['id' => 'L', 'label' => 'L', 'chest' => 44, 'length' => 29, 'shoulder' => 21],
    ['id' => 'XL', 'label' => 'XL', 'chest' => 48, 'length' => 30, 'shoulder' => 22],
    ['id' => '2XL', 'label' => '2XL', 'chest' => 52, 'length' => 31, 'shoulder' => 23],
    ['id' => '3XL', 'label' => '3XL', 'chest' => 56, 'length' => 32, 'shoulder' => 24]
];

// --- REAL SHOPEE MALL QUALITY FASHION CATALOG WITH MULTI-IMAGE GALLERIES ---
$DEFAULT_CATALOG = [
    [
        'id' => 'prod-oversized-tee',
        'category' => 't-shirts',
        'category_name' => 'เสื้อยืด (T-Shirts)',
        'name' => 'Apex Heavyweight Oversized Tee 220 GSM',
        'subtitle' => 'เสื้อยืดพรีออเดอร์ Oversized ผ้า Cotton Comb 100% สกรีนลายสตรีท HD',
        'price' => 390,
        'original_price' => 690,
        'sold_count' => 1420,
        'badge' => 'SHOPEE MALL',
        'badge_color' => 'bg-rose-600',
        'rating' => 4.9,
        'reviews_count' => 842,
        'image' => 'https://images.unsplash.com/photo-1521572267360-ee0c2909d518?w=800&auto=format&fit=crop&q=80',
        'gallery' => [
            'https://images.unsplash.com/photo-1521572267360-ee0c2909d518?w=800&auto=format&fit=crop&q=80',
            'https://images.unsplash.com/photo-1503342217505-b0a15ec3261c?w=800&auto=format&fit=crop&q=80',
            'https://images.unsplash.com/photo-1583743814966-8936f5b7be1a?w=800&auto=format&fit=crop&q=80',
            'https://images.unsplash.com/photo-1618354691373-d851c5c3a990?w=800&auto=format&fit=crop&q=80'
        ],
        'colors' => $COLOR_OPTIONS,
        'sizes' => ['S', 'M', 'L', 'XL', '2XL', '3XL'],
        'description' => 'เสื้อยืดพรีเมียม Heavyweight 220 GSM ทรง Oversized เกาหลี นุ่ม ใส่สบาย ไหล่ตก คอไม่ย้วย สกรีนลายคมชัดระดับ HD พร้อมรับประกันแท้ 100% คืนเงิน 2 เท่า'
    ],
    [
        'id' => 'prod-vintage-graphic-tee',
        'category' => 't-shirts',
        'category_name' => 'เสื้อยืด (T-Shirts)',
        'name' => 'Apex Vintage Washed Acid Graphic Tee',
        'subtitle' => 'เสื้อยืดวินเทจกัดสี Washed Cotton ลายสกรีน Retro Streetwear 90s',
        'price' => 450,
        'original_price' => 790,
        'sold_count' => 960,
        'badge' => 'BEST SELLER',
        'badge_color' => 'bg-amber-600',
        'rating' => 4.9,
        'reviews_count' => 489,
        'image' => 'https://images.unsplash.com/photo-1503342217505-b0a15ec3261c?w=800&auto=format&fit=crop&q=80',
        'gallery' => [
            'https://images.unsplash.com/photo-1503342217505-b0a15ec3261c?w=800&auto=format&fit=crop&q=80',
            'https://images.unsplash.com/photo-1521572267360-ee0c2909d518?w=800&auto=format&fit=crop&q=80',
            'https://images.unsplash.com/photo-1576566588028-4147f3842f27?w=800&auto=format&fit=crop&q=80'
        ],
        'colors' => [
            ['id' => 'vintage-black', 'name' => 'Washed Black (ดำวินเทจ)', 'hex' => '#27272a', 'collarHex' => '#18181b', 'textDark' => false, 'printColor' => '#fbbf24'],
            ['id' => 'vintage-grey', 'name' => 'Acid Grey (เทากรด)', 'hex' => '#52525b', 'collarHex' => '#3f3f46', 'textDark' => false, 'printColor' => '#f43f5e']
        ],
        'sizes' => ['S', 'M', 'L', 'XL', '2XL'],
        'description' => 'เสื้อยืดวินเทจผ่านเทคนิคการซัก Acid Washed ทำให้ผ้าสัมผัสนุ่มและมีเท็กซ์เจอร์ย้อนยุค ลายสกรีนกราฟฟิกสตรีทแฟชั่นเฉพาะตัว สวมใส่ได้ทั้งชายและหญิง'
    ],
    [
        'id' => 'prod-tactical-hoodie',
        'category' => 'hoodies',
        'category_name' => 'เสื้อกันหนาว/ฮู้ดดี้ (Hoodies & Jackets)',
        'name' => 'Apex Tactical Heavy Oversized Hoodie 400 GSM',
        'subtitle' => 'เสื้อฮู้ดดี้เนื้อหนาพิเศษ 400 GSM ทรงสตรีทพรีเมียม ปักโลโก้นูน 3D',
        'price' => 890,
        'original_price' => 1490,
        'sold_count' => 650,
        'badge' => 'FLASH SALE',
        'badge_color' => 'bg-orange-500',
        'rating' => 5.0,
        'reviews_count' => 312,
        'image' => 'https://images.unsplash.com/photo-1556905055-8f358a7a47b2?w=800&auto=format&fit=crop&q=80',
        'gallery' => [
            'https://images.unsplash.com/photo-1556905055-8f358a7a47b2?w=800&auto=format&fit=crop&q=80',
            'https://images.unsplash.com/photo-1509967419530-da38b4704bc6?w=800&auto=format&fit=crop&q=80',
            'https://images.unsplash.com/photo-1544441893-675973e31985?w=800&auto=format&fit=crop&q=80'
        ],
        'colors' => [
            ['id' => 'hoodie-black', 'name' => 'Jet Black (ดำเข้ม)', 'hex' => '#09090b', 'collarHex' => '#000000', 'textDark' => false, 'printColor' => '#ffffff'],
            ['id' => 'hoodie-cream', 'name' => 'Sand Beige (เบจทราย)', 'hex' => '#d6d3d1', 'collarHex' => '#a8a29e', 'textDark' => true, 'printColor' => '#1c1917']
        ],
        'sizes' => ['M', 'L', 'XL', '2XL'],
        'description' => 'เสื้อฮู้ดดี้ผ้าสำลีหนานุ่ม 400 GSM ทรง Oversized หมวกสองชั้นตั้งทรงสวย กระเป๋าหน้าใบใหญ่ พร้อมสายปรับกระชับ กันหนาวได้ดีเยี่ยม'
    ],
    [
        'id' => 'prod-denim-jacket',
        'category' => 'hoodies',
        'category_name' => 'เสื้อแจ็คเก็ตยีนส์ (Denim Jacket)',
        'name' => 'Apex Raw Denim Streetwear Jacket 14oz',
        'subtitle' => 'แจ็คเก็ตยีนส์ทรงครอปสตรีท ตัดเย็บด้วยผ้ายีนส์ริมแดงพรีเมียม',
        'price' => 1290,
        'original_price' => 1990,
        'sold_count' => 380,
        'badge' => 'SHOPEE MALL',
        'badge_color' => 'bg-rose-600',
        'rating' => 4.9,
        'reviews_count' => 174,
        'image' => 'https://images.unsplash.com/photo-1576995853123-5a10305d93c0?w=800&auto=format&fit=crop&q=80',
        'gallery' => [
            'https://images.unsplash.com/photo-1576995853123-5a10305d93c0?w=800&auto=format&fit=crop&q=80',
            'https://images.unsplash.com/photo-1543076447-215ad9ba6923?w=800&auto=format&fit=crop&q=80'
        ],
        'colors' => [
            ['id' => 'denim-indigo', 'name' => 'Raw Indigo (ยีนส์เข้ม)', 'hex' => '#1e3a8a', 'collarHex' => '#172554', 'textDark' => false, 'printColor' => '#ffffff'],
            ['id' => 'denim-washed', 'name' => 'Light Vintage Blue (ยีนส์อ่อน)', 'hex' => '#60a5fa', 'collarHex' => '#3b82f6', 'textDark' => true, 'printColor' => '#0f172a']
        ],
        'sizes' => ['M', 'L', 'XL'],
        'description' => 'แจ็คเก็ตยีนส์พรีเมียม 14oz ทรงคลาสสิกสตรีท ดีเทลปักโลโก้แบรนด์ด้านหลัง กระดุมโลหะแมทช์คัสตอม ใส่คลุมได้ทุกโอกาส'
    ],
    [
        'id' => 'prod-cargo-pants',
        'category' => 'pants',
        'category_name' => 'กางเกงคาร์โก้ (Pants)',
        'name' => 'Apex Utility Streetwear Cargo Pants',
        'subtitle' => 'กางเกงคาร์โก้ทรงกระบอกกว้าง กระเป๋าข้าง 6 ช่อง สายสตรีทสายลุย',
        'price' => 790,
        'original_price' => 1190,
        'sold_count' => 1120,
        'badge' => 'TOP 1',
        'badge_color' => 'bg-emerald-600',
        'rating' => 4.9,
        'reviews_count' => 520,
        'image' => 'https://images.unsplash.com/photo-1624378439575-d8705ad7ae80?w=800&auto=format&fit=crop&q=80',
        'gallery' => [
            'https://images.unsplash.com/photo-1624378439575-d8705ad7ae80?w=800&auto=format&fit=crop&q=80',
            'https://images.unsplash.com/photo-1552902865-b72c031ac5ea?w=800&auto=format&fit=crop&q=80'
        ],
        'colors' => [
            ['id' => 'cargo-black', 'name' => 'Matte Black (ดำด้าน)', 'hex' => '#18181b', 'collarHex' => '#09090b', 'textDark' => false, 'printColor' => '#ffffff'],
            ['id' => 'cargo-olive', 'name' => 'Military Green (เขียวทหาร)', 'hex' => '#3f6212', 'collarHex' => '#1a2e05', 'textDark' => false, 'printColor' => '#ffffff']
        ],
        'sizes' => ['S', 'M', 'L', 'XL'],
        'description' => 'กางเกงคาร์โก้ผ้าคอตตอนทวิลหนาทนทาน ทรง Relaxed Straight ขอบเอวยางยืดพร้อมสายเชือกปรับระดับได้ กระเป๋าใหญ่ 6 ช่อง'
    ],
    [
        'id' => 'prod-streetwear-cap',
        'category' => 'accessories',
        'category_name' => 'แอคเซสเซอรี่ (Accessories)',
        'name' => 'Apex 3D Embroidered Streetwear Cap',
        'subtitle' => 'หมวกแก๊ปสตรีทปักโลโก้นูน APEX งานตัดเย็บระดับพรีเมียม',
        'price' => 320,
        'original_price' => 550,
        'sold_count' => 740,
        'badge' => 'HOT',
        'badge_color' => 'bg-indigo-600',
        'rating' => 4.9,
        'reviews_count' => 310,
        'image' => 'https://images.unsplash.com/photo-1588850561407-ed78c282e89b?w=800&auto=format&fit=crop&q=80',
        'gallery' => [
            'https://images.unsplash.com/photo-1588850561407-ed78c282e89b?w=800&auto=format&fit=crop&q=80'
        ],
        'colors' => [
            ['id' => 'cap-black', 'name' => 'Stealth Black (ดำ)', 'hex' => '#18181b', 'collarHex' => '#09090b', 'textDark' => false, 'printColor' => '#ffffff']
        ],
        'sizes' => ['Free Size'],
        'description' => 'หมวกแก๊ประดับสตรีทแฟชั่น ทรงสวยไม่เสียรูป สายปรับไซส์ด้านหลังแบบบัคเคิลโลหะลุคหรูหรา'
    ]
];

// Helper to get custom and default products combined
function getAllProducts() {
    global $DEFAULT_CATALOG;
    $custom = [];
    if (file_exists(CUSTOM_PRODUCTS_FILE)) {
        $custom = json_decode(file_get_contents(CUSTOM_PRODUCTS_FILE), true) ?: [];
    }
    return array_merge($custom, $DEFAULT_CATALOG);
}

function saveCustomProduct($product) {
    $custom = [];
    if (file_exists(CUSTOM_PRODUCTS_FILE)) {
        $custom = json_decode(file_get_contents(CUSTOM_PRODUCTS_FILE), true) ?: [];
    }
    array_unshift($custom, $product);
    file_put_contents(CUSTOM_PRODUCTS_FILE, json_encode($custom, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
    return true;
}

// Helper to get total ordered count
function getTotalOrderedCount() {
    if (!file_exists(ORDERS_FILE)) return INITIAL_ORDER_OFFSET;
    $orders = json_decode(file_get_contents(ORDERS_FILE), true) ?: [];
    $totalFromDb = 0;
    foreach ($orders as $order) {
        if (isset($order['items']) && is_array($order['items'])) {
            foreach ($order['items'] as $item) {
                $totalFromDb += intval($item['quantity'] ?? 0);
            }
        }
    }
    return INITIAL_ORDER_OFFSET + $totalFromDb;
}

// Helper to get remaining stock count
function getRemainingStock() {
    $totalOrdered = getTotalOrderedCount();
    return max(0, TOTAL_STOCK_LIMIT - $totalOrdered);
}

// Helper to get all orders
function getAllOrders() {
    if (!file_exists(ORDERS_FILE)) return [];
    return json_decode(file_get_contents(ORDERS_FILE), true) ?: [];
}