tabular

type Column struct {
	Index     []int   // Field index path in the struct
	Name      string  // Column name (header)
	Width     float64 // Column width hint (for display/export)
	Order     int     // Column order (for sorting)
	Default   string  // Default value used during import when cell is empty
	Format    string  // Format template (e.g., date format, number format)
	Formatter string  // Custom formatter name for export
	Parser    string  // Custom parser name for import
}

type ExportError struct {
	Row    int
	Column string
	Field  string
	Err    error
}

type Exporter interface {
	// RegisterFormatter registers a custom formatter with the given name.
	RegisterFormatter(name string, formatter Formatter)
	// ExportToFile exports data to an Excel file.
	ExportToFile(data any, filename string) error
	// Export exports data to a bytes.Buffer.
	Export(data any) (*bytes.Buffer, error)
}

type Formatter interface {
	// Format converts a Go value to a cell string
	Format(value any) (string, error)
}

type ImportError struct {
	Row    int
	Column string
	Field  string
	Err    error
}

type Importer interface {
	// RegisterParser registers a custom parser with the given name.
	RegisterParser(name string, parser ValueParser)
	// ImportFromFile imports data from an Excel file.
	ImportFromFile(filename string) (any, []ImportError, error)
	// Import imports data from an io.Reader.
	Import(reader io.Reader) (any, []ImportError, error)
}

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

type ValueParser interface {
	// Parse converts a cell string to a Go value
	Parse(cellValue string, targetType reflect.Type) (any, error)
}