feat(tasks): implement atomic claims and leases

backend-api/internal/domain/task.go

@@ -33,38 +33,62 @@ const (
 )
 
 type PurchaseTask struct {
-	ID              string
-	CreatorSubject  string
-	CreatedByUserID *string
-	SourceRef       *string
-	Title           string
-	Description     string
-	SKU             string
-	ImageAssetID    string
-	Quantity        int
-	MaxBudgetCents  *int64
-	Currency        string
-	Status          TaskStatus
-	Version         int64
-	CancelReason    *string
-	CanceledAt      *time.Time
-	CreatedAt       time.Time
-	UpdatedAt       time.Time
+	ID                      string
+	CreatorSubject          string
+	CreatedByUserID         *string
+	SourceRef               *string
+	Title                   string
+	Description             string
+	SKU                     string
+	ImageAssetID            string
+	Quantity                int
+	MaxBudgetCents          *int64
+	Currency                string
+	Status                  TaskStatus
+	Version                 int64
+	ClaimedByUserID         *string
+	ClaimedByDeviceID       *string
+	ClaimGeneration         int64
+	ClaimTokenHash          *string
+	ClaimIssuedAt           *time.Time
+	ClaimExpiresAt          *time.Time
+	CancelReason            *string
+	CancelRequestedAt       *time.Time
+	CancelRequestedByUserID *string
+	CanceledAt              *time.Time
+	CreatedAt               time.Time
+	UpdatedAt               time.Time
 }
 
 type TaskEvent struct {
-	ID          string
-	TaskID      string
-	ActorUserID *string
-	Type        string
-	Message     string
-	OccurredAt  time.Time
+	ID            string
+	TaskID        string
+	ActorUserID   *string
+	ActorDeviceID *string
+	Type          string
+	Message       string
+	OccurredAt    time.Time
+}
+
+type TaskExecution struct {
+	ID              string
+	TaskID          string
+	AttemptNo       int64
+	ClaimGeneration int64
+	UserID          string
+	DeviceID        string
+	CurrentStep     string
+	OrderSubmitted  bool
+	StartedAt       time.Time
+	LastHeartbeatAt *time.Time
+	FinishedAt      *time.Time
 }
 
 type TaskDetail struct {
-	Task   PurchaseTask
-	Asset  Asset
-	Events []TaskEvent
+	Task      PurchaseTask
+	Asset     Asset
+	Execution *TaskExecution
+	Events    []TaskEvent
 }
 
 type TaskValidationError struct {
@@ -192,7 +216,45 @@ func FormatOptionalCNY(cents *int64) *string {
 }
 
 func CanCancel(status TaskStatus) bool {
-	return status == TaskStatusPending
+	return CanAdminCancelImmediately(status) || CanRequestCancel(status)
+}
+
+func IsActiveTaskStatus(status TaskStatus) bool {
+	switch status {
+	case TaskStatusClaimed,
+		TaskStatusRunning,
+		TaskStatusWaitingConfirmation:
+		return true
+	default:
+		return false
+	}
+}
+
+func CanStart(status TaskStatus) bool {
+	return status == TaskStatusClaimed
+}
+
+func CanHeartbeat(status TaskStatus) bool {
+	return status == TaskStatusRunning ||
+		status == TaskStatusWaitingConfirmation
+}
+
+func CanRelease(status TaskStatus) bool {
+	return status == TaskStatusClaimed
+}
+
+func CanAdminCancelImmediately(status TaskStatus) bool {
+	return status == TaskStatusPending ||
+		status == TaskStatusClaimed
+}
+
+func CanRequestCancel(status TaskStatus) bool {
+	return status == TaskStatusRunning ||
+		status == TaskStatusWaitingConfirmation
+}
+
+func CanAcknowledgeCancel(status TaskStatus) bool {
+	return CanRequestCancel(status)
 }
 
 func IsValidTaskStatus(status TaskStatus) bool {