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# Track Purchase Event

#### Track Purchase Event

This function logs a purchase event with the specified order ID, purchase amount, currency, and optional additional parameters. It is used to track purchase transactions within an application.

**Method Signature:**

```java
fun trackPurchaseEvent(orderId: String?, purchaseAmount: Double, currency: String?, parameters: Bundle? = null)
```

**Parameters:**

* `orderId` (String?): The unique identifier for the order. This parameter is optional and can be null.
* `purchaseAmount` (Double): The total amount of the purchase.
* `currency` (String?): The currency of the purchase amount. This parameter is optional and can be null.
* `parameters` (Bundle?, optional): A `Bundle` containing key-value pairs of additional data to be logged with the purchase event. This parameter is optional and can be null.

**Example Usage:**

```java
// Without parameters
trackPurchaseEvent("12345", 99.99, "USD")

// With parameters
val params = Bundle().apply {
    putString("payment_method", "credit_card")
    putString("customer_type", "new")
}
trackPurchaseEvent("12345", 99.99, "USD", params)
```