backend-php/models/OrderbookModel.php

<?php

namespace Models;

class OrderbookModel
{
    private \PDO $pdo;

    public function __construct()
    {
        if (isset($GLOBALS['pdo']) && $GLOBALS['pdo'] instanceof \PDO) {
            $this->pdo = $GLOBALS['pdo'];
            return;
        }

        throw new \RuntimeException('Global PDO connection not initialized');
    }

    /**
     * @param array{
     *   orderbook_flag:string,
     *   orderbook_ts:int,
     *   orderbook_is_token:bool,
     *   orderbook_amount:string,
     *   status_id:int,
     *   user_id:int,
     *   wallet_id:int,
     *   token_id:int,
     *   currency_id:?int,
     *   chain_id:int
     * } $data
     */
    public function create(array $data): array
    {
        $stmt = $this->pdo->prepare(
            'INSERT INTO "orderbook" (
                orderbook_flag,
                orderbook_ts,
                orderbook_is_token,
                orderbook_amount,
                status_id,
                user_id,
                wallet_id,
                token_id,
                currency_id,
                chain_id
            ) VALUES (
                :orderbook_flag,
                :orderbook_ts,
                :orderbook_is_token,
                :orderbook_amount,
                :status_id,
                :user_id,
                :wallet_id,
                :token_id,
                :currency_id,
                :chain_id
            ) RETURNING orderbook_id'
        );

        $stmt->execute([
            'orderbook_flag' => $data['orderbook_flag'],
            'orderbook_ts' => $data['orderbook_ts'],
            'orderbook_is_token' => $data['orderbook_is_token'],
            'orderbook_amount' => $data['orderbook_amount'],
            'status_id' => $data['status_id'],
            'user_id' => $data['user_id'],
            'wallet_id' => $data['wallet_id'],
            'token_id' => $data['token_id'],
            'currency_id' => $data['currency_id'],
            'chain_id' => $data['chain_id'],
        ]);

        $orderbookId = (int)$stmt->fetchColumn();

        return [
            'orderbook_id' => $orderbookId,
            'orderbook_ts' => $data['orderbook_ts'],
        ];
    }
}