package main

import (
	"strings"

	"github.com/miekg/dns"
)

// loadUnparsedArgs tries to parse all the arguments
// which are unparsed by `flag` library. These arguments don't have any specific
// order so we have to deduce based on the pattern of argument.
// For eg, a nameserver must always begin with `@`. In this
// pattern we deduce the arguments and append it to the
// list of internal query flags.
// In case an argument isn't able to fit in any of the existing
// pattern it is considered to be a "hostname".
// Eg of unparsed argument: `dig mrkaran.dev @1.1.1.1 AAAA`
// where `@1.1.1.1` and `AAAA` are "unparsed" args.
// Returns a list of nameserver, queryTypes, queryClasses, queryNames.
func loadUnparsedArgs(args []string) ([]string, []string, []string, []string) {
	var ns, qt, qc, qn []string
	for _, arg := range args {
		if strings.HasPrefix(arg, "@") {
			ns = append(ns, strings.Trim(arg, "@"))
		} else if _, ok := dns.StringToType[strings.ToUpper(arg)]; ok {
			qt = append(qt, arg)
		} else if _, ok := dns.StringToClass[strings.ToUpper(arg)]; ok {
			qc = append(qc, arg)
		} else {
			// if nothing matches, consider it's a query name.
			qn = append(qn, arg)
		}
	}
	return ns, qt, qc, qn
}

// contains is a helper method to check if a paritcular element exists in the slice.
func contains(s []string, e string) bool {
	for _, a := range s {
		if a == e {
			return true
		}
	}
	return false
}