/*!
 * Copyright 2017 Vpn.Email network security technology Canada Inc. All Rights Reserved.
 *
 * Vpn.Email network technolog Canada Ltd.
 * 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.
 */     
	  

	  
	  // =======================================================================
      /*
        +----+-----+-------+------+----------+----------+
        |VER | CMD |  RSV  | ATYP | DST.ADDR | DST.PORT |
        +----+-----+-------+------+----------+----------+
        | 1  |  1  | X'00' |  1   | Variable |    2     |
        +----+-----+-------+------+----------+----------+

        Where:

              o  VER    protocol version: X'05'
              o  CMD
                 o  CONNECT X'01'
                 o  BIND X'02'
                 o  UDP ASSOCIATE X'03'
              o  RSV    RESERVED
              o  ATYP   address type of following address
                 o  IP V4 address: X'01'
                 o  DOMAINNAME: X'03'
                 o  IP V6 address: X'04'
              o  DST.ADDR       desired destination address
              o  DST.PORT desired destination port in network octet
                 order
      */
const connectRequest = new Buffer ( '050100', 'hex' )
export const CMD = {
	CONNECT: 0x1,
	BIND: 0x2,
	UDP_ASSOCIATE: 0x3
}
export const ATYP = {
	IP_V4: 0x1,
	DOMAINNAME: 0x03,
	IP_V6: 0x4
}

export const Replies = {
	GRANTED: 0x0,
	GENERAL_FAILURE: 0x1,
	CONNECTION_NOT_ALLOWED_BY_RULESET: 0x2,
	NETWORK_UNREACHABLE: 0x3,
	HOST_UNREACHABLE: 0x4,
	CONNECTION_REFUSED_BY_DESTINATION_HOST: 0x5,
	TTL_EXPIRED: 0x6,
	COMMAND_NOT_SUPPORTED_or_PROTOCOL_ERROR: 0x7,
	ADDRESS_TYPE_NOT_SUPPORTED: 0x8
}
//		state 
	const STATE_VERSION = 0
	const STATE_METHOD = 1
	const STATE_REP_STATUS = 2
	const STATE_REP_RSV = 3
	const STATE_REP_ATYP = 4
	const STATE_REP_BNDADDR = 5
	const STATE_REP_BNDADDR_VARLEN = 6
	const STATE_REP_BNDPORT = 7
//		end stats
//		reply Buffer
	
	const reply_NO_AUTHENTICATION_REQUIRED = new Buffer ( '0500', 'hex' )
	const reply_GSSAPI = new Buffer ( '0501', 'hex' )
	const reply_USERNAME_PASSWORD = new Buffer ( '0502', 'hex' )
	const reply_to_x7F_IANA_ASSIGNED = new Buffer ( '0503', 'hex' )
	const reply_to_xFE_RESERVED_FOR_PRIVATE_METHODS = new Buffer ( '0580', 'hex' )
	const reply_NO_ACCEPTABLE_METHODS = new Buffer ( '05ff', 'hex' )
//		end reply Buffer

export class  Requests {

	constructor ( public buffer: Buffer ) {}
	public get socketVersion () {
		return this.buffer.readUInt8 ( 0 )
	}
	
	public get IsSocket5 () {
		return this.buffer.readUInt8 ( 0 ) === 0x05
	}
	public get NMETHODS () {
		return this.buffer.readUInt8 ( 1 )
	}
	public get METHODS () {
		return this.buffer.readUInt8 ( 2 )
	}
	public get isRequests () {
		return this.buffer.length > 3
	}
	public get domainLength () {
		return this.buffer.readUInt8 ( 4 )
	}
	public get domainName () {
		if ( this.ATYP !== ATYP.DOMAINNAME )
			return null
		return this.buffer.toString ( 'utf8', 5, 5 + this.domainLength )
	}
	public get ATYP () {
		return this.buffer.readInt8 ( 3 )
	}
	public set_V5 () {
		this.buffer.writeUInt8 (0, 0x5)
	}
	public set status ( n: number ) {
		this.buffer.writeUInt8 ( n, 1 )
	}

	public get ATYP_IP4Address () {
		if ( this.ATYP !== ATYP.IP_V4 )
			return null
		return `${ this.buffer.readUInt8 (4).toString() }.${ this.buffer.readUInt8 (5).toString() }.${ this.buffer.readUInt8 (6).toString() }.${ this.buffer.readUInt8 (7).toString() }`
	}

	public get port () {
		if ( this.ATYP === ATYP.DOMAINNAME ) {
			const length = this.buffer.readUInt8 ( 4 )
			return this.buffer.readUInt16BE ( 5 + length )
		}
		if ( this.ATYP === ATYP.IP_V6 )
			return this.buffer.readUInt16BE ( 19 )
		return this.buffer.readUInt16BE ( 8 )
	}

	public get IPv6 () {
		if ( this.ATYP !== ATYP.IP_V6 )
			return null
		return `${ this.buffer.readUInt32BE (4).toString (16) }:${ this.buffer.readUInt32BE (8).toString(16) }:${ this.buffer.readUInt32BE (12).toString(16) }:${ this.buffer.readUInt32BE (16).toString (16) }`
	}

	public get cmd () {
		return this.buffer.readUInt8 (1)
	}

	public set ATYP_IP4Address ( n: string ) {
		if ( this.ATYP !== ATYP.IP_V4 )
			return
		const y = n.split ('.')
		const ret = new Buffer ('00000000','hex')
		for ( let i = 0; i < 4; i ++ ) {
			const k = parseInt (y[i])
			if ( !k || k < 0 || k > 255 )
				return
			ret.writeUInt8 ( k, i )
		}
		this.buffer.fill ( ret, 4, 8 )
	}

	public set REP ( n: number ) {
		this.buffer.writeUInt8 ( n, 1 )
	}

	public get host () {
		return this.ATYP_IP4Address || this.domainName || this.IPv6
	}

	
}