package tokenize

import (
	"fmt"
)

// Input provides input-related functionality for the tokenize API,
// which is not specifically bound to a specific read mode (byte, rune).
type Input struct {
	api  *API
	Byte InputByteMode
	Rune InputRuneMode
}

// Cursor returns a string that describes the current read cursor position.
func (i Input) Cursor() string {
	if i.api.pointers.line == 0 && i.api.pointers.column == 0 {
		return fmt.Sprintf("start of file")
	}
	return fmt.Sprintf("line %d, column %d", i.api.pointers.line+1, i.api.pointers.column+1)
}

// Flush flushes input data from the read buffer up to the current
// read cursor position of the tokenizer.
//
// Note: in most cases, you won't have to call this method yourself.
// Parsekit will call this method at points where it knows it is a
// safe thing to do.
func (i Input) Flush() {
	a := i.api
	if a.pointers.offset > 0 {
		a.reader.Flush(a.pointers.offset)
		a.pointers.offset = 0
	}
}