// Copyright 2016 Apcera Inc. All rights reserved.

package auth

import (
	"golang.org/x/crypto/bcrypt"

	"github.com/nats-io/gnatsd/server"
)

// Plain authentication is a basic username and password
type MultiUser struct {
	users map[string]string
}

// Create a new multi-user
func NewMultiUser(users []server.User) *MultiUser {
	m := &MultiUser{users: make(map[string]string)}
	for _, u := range users {
		m.users[u.Username] = u.Password
	}
	return m
}

// Check authenticates the client using a username and password against a list of multiple users.
func (m *MultiUser) Check(c server.ClientAuth) bool {
	opts := c.GetOpts()
	pass, ok := m.users[opts.Username]
	if !ok {
		return false
	}
	// Check to see if the password is a bcrypt hash
	if isBcrypt(pass) {
		if err := bcrypt.CompareHashAndPassword([]byte(pass), []byte(opts.Password)); err != nil {
			return false
		}
	} else if pass != opts.Password {
		return false
	}
	return true
}