package parsekit

import (
	"fmt"
)

// Error is used as the error type when parsing errors occur.
// The error includes some context information to allow for useful
// error messages to the user.
type Error struct {
	Message string
	Line    int
	Column  int
}

func (err *Error) Error() string {
	return err.Message
}

// Full returns the current error message, including information about
// the position in the input where the error occurred.
func (err *Error) Full() string {
	return fmt.Sprintf("%s at line %d, column %d", err, err.Line, err.Column)
}

// Error sets the error message in the parser API. This error message
// will eventually be returned by the Parser.Execute() method.
func (p *ParseAPI) Error(format string, args ...interface{}) {
	// No call to p.panicWhenStoppedOrInError(), to allow a parser to
	// set a different error message when needed.
	message := fmt.Sprintf(format, args...)
	p.err = &Error{message, p.cursorLine, p.cursorColumn}
}