io

type ConvertJob struct {
	Source      Reader
	Target      Writer
	Schema      *encoding.Schema
	KeepPulseAt string // optional: also write intermediate .pulse
	SampleRows  int
	FS          afero.Fs
}

type ConvertReport struct {
	RowsConverted int
	Schema        *encoding.Schema
	RowErrors     []RowError
}

type ExportJob struct {
	Source string // input .pulse path
	Target Writer
	FS     afero.Fs
}

type ExportReport struct {
	RowsExported int
	RowErrors    []RowError
}

type ImportJob struct {
	Source     Reader
	Target     string // output .pulse path
	Schema     *encoding.Schema
	SampleRows int // default 500, min 50
	FS         afero.Fs
}

type ImportReport struct {
	RowsImported int
	Schema       *encoding.Schema
	RowErrors    []RowError
}

type InferenceWarning struct {
	Column  string
	Message string
}

type PredictReport struct {
	Schema        *encoding.Schema
	EstimatedRows int
	Warnings      []InferenceWarning
}

type Reader interface {
	// ReadHeader returns column names from the source.
	ReadHeader() ([]string, error)
	// ReadRows streams rows; calls fn for each row.
	// The context controls cancellation.
	ReadRows(ctx context.Context, fn func(row []string) error) error
	// Close releases underlying resources.
	Close() error
}

type ResetReader interface {
	Reader
	// Reset rewinds the reader to the beginning.
	Reset() error
}

type RowError struct {
	Row int
	Err error
}

type Writer interface {
	// WriteHeader writes column names to the target.
	WriteHeader(columns []string) error
	// WriteRow writes a single row of values.
	WriteRow(values []any) error
	// Close flushes and releases resources.
	Close() error
}