engine

type ExecutionObserver interface {
	FlowStarted(evt FlowStartedEvent)
	NodeStarted(evt NodeStartedEvent)
	NodeFinished(evt NodeFinishedEvent)
	FlowFinished(evt FlowFinishedEvent)
}

type FlowEngine struct {
	// contains filtered or unexported fields
}

type FlowFinishedEvent struct {
	FlowName   string
	StartedAt  time.Time
	FinishedAt time.Time
	DurationMs int64
	Result     *spi.FlowExecutionResult
}

type FlowStartedEvent struct {
	FlowName  string
	StartedAt time.Time
}

type Middleware func(NodeExecutor) NodeExecutor

type NodeExecutor func(spi.ExecutionContext) (spi.AnyResult, error)

type NodeFinishedEvent struct {
	NodeID      string
	DisplayName string
	NodeType    spi.Kind
	StartedAt   time.Time
	FinishedAt  time.Time
	DurationMs  int64
	Result      spi.AnyResult
}

type NodeStartedEvent struct {
	NodeID      string
	DisplayName string
	NodeType    spi.Kind
	StartedAt   time.Time
}

type NoopObserver struct{}

type Options struct {
	Observer        ExecutionObserver
	ModuleResolver  spi.ModuleResolver
	ModuleCallStack []string
	DynamicVars     spi.DynamicResolver
	// Ctx is the request-scoped context propagated to every node execution for
	// cancellation/deadlines. Nil is treated as context.Background().
	Ctx context.Context
	// Middleware wraps each node's execution (retry/timeout/tracing). Outermost first.
	Middleware []Middleware
}