// Copyright (c) 2019 The BFE Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// Copyright (c) pires.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package bfe_proxy

// ProtocolVersionAndCommand represents proxy protocol version and command.
type ProtocolVersionAndCommand byte

const (
	LOCAL = '\x20'
	PROXY = '\x21'
)

var supportedCommand = map[ProtocolVersionAndCommand]bool{
	LOCAL: true,
	PROXY: true,
}

// IsLocal returns true if the protocol version is \x2 and command is LOCAL, false otherwise.
func (pvc ProtocolVersionAndCommand) IsLocal() bool {
	return 0x20 == pvc&0xF0 && 0x00 == pvc&0x0F
}

// IsProxy returns true if the protocol version is \x2 and command is PROXY, false otherwise.
func (pvc ProtocolVersionAndCommand) IsProxy() bool {
	return 0x20 == pvc&0xF0 && 0x01 == pvc&0x0F
}

// IsUnspec returns true if the protocol version or command is unspecified, false otherwise.
func (pvc ProtocolVersionAndCommand) IsUnspec() bool {
	return !(pvc.IsLocal() || pvc.IsProxy())
}

func (pvc ProtocolVersionAndCommand) toByte() byte {
	if pvc.IsLocal() {
		return LOCAL
	} else if pvc.IsProxy() {
		return PROXY
	}

	return LOCAL
}
