Added arn to the main repository

arn/Purchase.go

@@ -0,0 +1,78 @@
+package arn
+
+import "github.com/aerogo/nano"
+
+// Purchase represents an item purchase by a user.
+type Purchase struct {
+	ID       string `json:"id"`
+	UserID   string `json:"userId"`
+	ItemID   string `json:"itemId"`
+	Quantity int    `json:"quantity"`
+	Price    int    `json:"price"`
+	Currency string `json:"currency"`
+	Date     string `json:"date"`
+}
+
+// Item returns the item the user bought.
+func (purchase *Purchase) Item() *ShopItem {
+	item, _ := GetShopItem(purchase.ItemID)
+	return item
+}
+
+// User returns the user who made the purchase.
+func (purchase *Purchase) User() *User {
+	user, _ := GetUser(purchase.UserID)
+	return user
+}
+
+// NewPurchase creates a new Purchase object with a generated ID.
+func NewPurchase(userID UserID, itemID string, quantity int, price int, currency string) *Purchase {
+	return &Purchase{
+		ID:       GenerateID("Purchase"),
+		UserID:   userID,
+		ItemID:   itemID,
+		Quantity: quantity,
+		Price:    price,
+		Currency: currency,
+		Date:     DateTimeUTC(),
+	}
+}
+
+// StreamPurchases returns a stream of all purchases.
+func StreamPurchases() <-chan *Purchase {
+	channel := make(chan *Purchase, nano.ChannelBufferSize)
+
+	go func() {
+		for obj := range DB.All("Purchase") {
+			channel <- obj.(*Purchase)
+		}
+
+		close(channel)
+	}()
+
+	return channel
+}
+
+// AllPurchases returns a slice of all anime.
+func AllPurchases() ([]*Purchase, error) {
+	all := make([]*Purchase, 0, DB.Collection("Purchase").Count())
+
+	for obj := range StreamPurchases() {
+		all = append(all, obj)
+	}
+
+	return all, nil
+}
+
+// FilterPurchases filters all purchases by a custom function.
+func FilterPurchases(filter func(*Purchase) bool) ([]*Purchase, error) {
+	var filtered []*Purchase
+
+	for obj := range StreamPurchases() {
+		if filter(obj) {
+			filtered = append(filtered, obj)
+		}
+	}
+
+	return filtered, nil
+}