feat: generate invoice for overdraft credits

billing/config.go

@@ -30,6 +30,10 @@ type AccountConfig struct {
 	DefaultPlan           string `yaml:"default_plan" mapstructure:"default_plan"`
 	DefaultOffline        bool   `yaml:"default_offline" mapstructure:"default_offline"`
 	OnboardCreditsWithOrg int64  `yaml:"onboard_credits_with_org" mapstructure:"onboard_credits_with_org"`
+
+	// CreditOverdraftProduct helps identify the product pricing per unit amount for the overdraft
+	// credits being invoiced
+	CreditOverdraftProduct string `yaml:"credit_overdraft_product" mapstructure:"credit_overdraft_product"`
 }
 
 type PlanChangeConfig struct {

billing/credit/credit.go

@@ -2,6 +2,7 @@ package credit
 
 import (
 	"errors"
+	"strings"
 	"time"
 
 	"github.com/google/uuid"
@@ -20,10 +21,11 @@ var (
 	// TxNamespaceUUID is the namespace for generating transaction UUIDs deterministically
 	TxNamespaceUUID = uuid.MustParse("967416d0-716e-4308-b58f-2468ac14f20a")
 
-	SourceSystemBuyEvent     = "system.buy"
-	SourceSystemAwardedEvent = "system.awarded"
-	SourceSystemOnboardEvent = "system.starter"
-	SourceSystemRevertEvent  = "system.revert"
+	SourceSystemBuyEvent       = "system.buy"
+	SourceSystemAwardedEvent   = "system.awarded"
+	SourceSystemOnboardEvent   = "system.starter"
+	SourceSystemRevertEvent    = "system.revert"
+	SourceSystemOverdraftEvent = "system.overdraft"
 )
 
 type TransactionType string
@@ -71,3 +73,7 @@ type Filter struct {
 	StartRange time.Time
 	EndRange   time.Time
 }
+
+func TxUUID(tags ...string) string {
+	return uuid.NewSHA1(TxNamespaceUUID, []byte(strings.Join(tags, ":"))).String()
+}

billing/customer/customer.go

@@ -82,6 +82,9 @@ type Filter struct {
 	OrgID      string
 	ProviderID string
 	State      State
+
+	Online           *bool
+	AllowedOverdraft *bool
 }
 
 type PaymentMethod struct {

billing/invoice/invoice.go

@@ -14,11 +14,31 @@ var (
 	ErrInvalidDetail = fmt.Errorf("invalid invoice detail")
 )
 
+const (
+	ItemTypeMetadataKey   = "item_type"
+	ReconciledMetadataKey = "reconciled"
+
+	GenerateForCreditLockKey = "generate_for_credit"
+)
+
+type State string
+
+func (s State) String() string {
+	return string(s)
+}
+
+const (
+	DraftState State = "draft"
+	OpenState  State = "open"
+	PaidState  State = "paid"
+)
+
 type Invoice struct {
-	ID            string
-	CustomerID    string
-	ProviderID    string
-	State         string
+	ID         string
+	CustomerID string
+	ProviderID string
+	// State could be one of draft, open, paid, uncollectible, void
+	State         State
 	Currency      string
 	Amount        int64
 	HostedURL     string
@@ -28,12 +48,39 @@ type Invoice struct {
 	PeriodStartAt time.Time
 	PeriodEndAt   time.Time
 
+	Items    []Item
 	Metadata metadata.Metadata
 }
 
+type ItemType string
+
+func (t ItemType) String() string {
+	return string(t)
+}
+
+const (
+	// CreditItemType is used to charge for the credits used in the system
+	// as overdraft
+	CreditItemType ItemType = "credit"
+)
+
+type Item struct {
+	ID         string `json:"id"`
+	ProviderID string `json:"provider_id"`
+	// Name is the item name
+	Name string `json:"name"`
+	// Type is the item type
+	Type ItemType `json:"type"`
+	// UnitAmount is per unit cost
+	UnitAmount int64 `json:"unit_amount"`
+	// Quantity is the number of units
+	Quantity int64 `json:"quantity"`
+}
+
 type Filter struct {
 	CustomerID  string
 	NonZeroOnly bool
+	State       State
 
 	Pagination *pagination.Pagination
 }