package rpc

import (
	"bytes"
	"encoding/binary"

	"github.com/9seconds/mtg/mtproto"
)

type RPCProxyRequestFlags uint32

const (
	RPCProxyRequestFlagsHasAdTag     RPCProxyRequestFlags = 0x8
	RPCProxyRequestFlagsEncrypted                         = 0x2
	RPCProxyRequestFlagsMagic                             = 0x1000
	RPCProxyRequestFlagsExtMode2                          = 0x20000
	RPCProxyRequestFlagsIntermediate                      = 0x20000000
	RPCProxyRequestFlagsAbdridged                         = 0x40000000
	RPCProxyRequestFlagsQuickAck                          = 0x80000000
)

var rpcProxyRequestFlagsEncryptedPrefix [8]byte

func (r RPCProxyRequestFlags) Bytes() []byte {
	converted := make([]byte, 4)
	binary.LittleEndian.PutUint32(converted, uint32(r))

	return converted
}

func NewRPCRproxyRequestFlags(connectionType mtproto.ConnectionType, quickAck bool, message []byte) RPCProxyRequestFlags {
	flags := RPCProxyRequestFlagsHasAdTag
	flags |= RPCProxyRequestFlagsMagic
	flags |= RPCProxyRequestFlagsExtMode2

	switch connectionType {
	case mtproto.ConnectionTypeAbridged:
		flags |= RPCProxyRequestFlagsAbdridged
	case mtproto.ConnectionTypeIntermediate:
		flags |= RPCProxyRequestFlagsIntermediate
	}

	if quickAck {
		flags |= RPCProxyRequestFlagsQuickAck
	}
	if bytes.HasPrefix(message, rpcProxyRequestFlagsEncryptedPrefix[:]) {
		flags |= RPCProxyRequestFlagsEncrypted
	}

	return flags
}