package instruction

import (
	"strings"
)

type alias struct {
	raw string
	// Name of the alias
	Name string
	// Value to resolve to
	Value string
}

func (d *alias) Raw() string { return strings.Join([]string{"alias", d.raw}, " ") }

func (d *alias) Build(_args string) error {

	// 1. extract action fields ()
	split := strings.SplitN(_args, " ", 2)

	// 2. check syntax
	if len(split) != 2 {
		return ErrInvalidSyntax
	}

	if strings.Contains(split[0], "/") {
		return ErrInvalidAlias
	}

	d.Name = strings.Trim(split[0], " \t")
	d.Value = strings.Trim(split[1], " \t")
	d.raw = _args

	return nil
}

func (d alias) Exec(ctx ExecutionContext) ([]byte, error) {
	ctx.Alias[d.Name] = d.Value
	return nil, nil
}