engine

type Deps struct {
	// Source yields the records to classify. Required.
	Source source.Source
	// Stages is the cascade, cheapest first. At least one is required.
	Stages []stage.Stage
	// Sink receives every classified record. Required.
	Sink sink.Sink
	// Review receives records no stage could classify, with a zero
	// Classification. Optional; when nil such records are dropped.
	Review sink.Sink
	// Logger defaults to slog.Default.
	Logger *slog.Logger
	// MinConfidence is the gate: a stage's classification below this
	// threshold is treated as undecided and the record escalates to the
	// next stage. Zero disables gating. Deterministic stages emit 1, so
	// they always pass.
	MinConfidence float64
	// Workers is how many goroutines classify at once. Zero or one keeps
	// the serial loop. More requires stages safe for concurrent Classify,
	// and the engine closes the Source when a failure ends the run early.
	// Order, errors, and Stats match the serial loop exactly.
	Workers int
}

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

type Stats struct {
	// Processed counts records read from the source.
	Processed int
	// Classified counts records some stage decided.
	Classified int
	// Reviewed counts records no stage decided, whether routed to the
	// review sink or dropped.
	Reviewed int
	// ByStage counts classifications per stage name.
	ByStage map[string]int
}