use v6.c;
unit class Net::Telnet::Chunk;

enum TelnetOption is export (
    'TRANSMIT_BINARY'     => 0x00.chr,
    'ECHO'                => 0x01.chr,
    'RCP'                 => 0x02.chr, # Reconnection
    'SGA'                 => 0x03.chr, # Suppress Go Ahead
    'NAMS'                => 0x04.chr, # Message Size Negotiation
    'STATUS'              => 0x05.chr,
    'TIMING_MARK'         => 0x06.chr,
    'RCTE'                => 0x07.chr, # Remote Controlled Trans and Echo
    'NAOL'                => 0x08.chr, # Output Line Width
    'NAOP'                => 0x09.chr, # Output Line Height
    'NAOCRD'              => 0x0A.chr, # Output Carriage-Return Disposition
    'NAOHTS'              => 0x0B.chr, # Output Horizontal Tab Stops
    'NAOHTD'              => 0x0C.chr, # Output Horizontal Tab Disposition
    'NAOFFD'              => 0x0D.chr, # Output Formfeed Disposition
    'NAOVTS'              => 0x0E.chr, # Output Vertical Stops
    'NAOVTD'              => 0x0F.chr, # Output Vertical Disposition
    'NAOLFD'              => 0x10.chr, # Output Linefeed Disposition
    'XASCII'              => 0x11.chr, # Extended ASCII
    'LOGOUT'              => 0x12.chr,
    'BM'                  => 0x13.chr, # Byte Macro
    'DET'                 => 0x14.chr, # Data Entry Terminal
    'SUPDUP'              => 0x15.chr,
    'SUPDUP_OUTPUT'       => 0x16.chr,
    'SEND_LOCATION'       => 0x17.chr,
    'TERMINAL_TYPE'       => 0x18.chr,
    'END_OF_RECORD'       => 0x19.chr,
    'TUID'                => 0x1A.chr, # TACACS User Identification
    'OUTMRK'              => 0x1B.chr, # Output Marking
    'TTYLOC'              => 0x1C.chr, # Terminal Location Number
    '3270_REGIME'         => 0x1D.chr,
    'X_3_PAD'             => 0x1E.chr,
    'NAWS'                => 0x1F.chr, # Negotiate About Window Size
    'TERMINAL_SPEED'      => 0x20.chr,
    'TOGGLE_FLOW_CONTROL' => 0x21.chr,
    'LINEMODE'            => 0x22.chr,
    'XDISPLOC'            => 0x23.chr, # X Display Location
    'ENVIRON'             => 0x24.chr, # Environment
    'AUTHENTICATION'      => 0x25.chr,
    'ENCRYPT'             => 0x26.chr,
    'NEW_ENVIRON'         => 0x27.chr,
    'TN3270E'             => 0x28.chr,
    'XAUTH'               => 0x29.chr,
    'CHARSET'             => 0x2A.chr,
    'RSP'                 => 0x2B.chr, # Remote Serial Port
    'COM_PORT_OPTION'     => 0x2C.chr,
    'SLE'                 => 0x2D.chr, # Suppress Local Echo
    'START_TLS'           => 0x2E.chr,
    'KERMIT'              => 0x2F.chr,
    'SEND_URL'            => 0x30.chr,
    'FORWARD_X'           => 0x31.chr,
    'PRAGMA_LOGON'        => 0x8A.chr,
    'SSPI_LOGON'          => 0x8B.chr,
    'PRAGMA_HEARTBEAT'    => 0x8C.chr,
    'EXOPL'               => 0xFF.chr
);

enum TelnetCommand is export (
    'SE'   => 0xF0.chr, # Subnegotiation End
    'NOP'  => 0xF1.chr, # No Operation
    'DM'   => 0xF2.chr, # Data Mark
    'BRK'  => 0xF3.chr, # Break
    'IP'   => 0xF4.chr, # Interrupt Process
    'AO'   => 0xF5.chr, # Abort Output
    'AYT'  => 0xF6.chr, # Are You There?
    'EC'   => 0xF7.chr, # Erase Character
    'EL'   => 0xF8.chr, # Erase Line
    'GA'   => 0xF9.chr, # Go Ahead
    'SB'   => 0xFA.chr, # Subnegotiation Begin
    'WILL' => 0xFB.chr,
    'WONT' => 0xFC.chr,
    'DO'   => 0xFD.chr,
    'DONT' => 0xFE.chr,
    'IAC'  => 0xFF.chr  # Interpret As Command
);

grammar Grammar {
    method debug($/, $message) {
        note $message;
        note "Commannd: $/";
    }

    token TOP { <chunk>+ }

    token chunk {
        :my TelnetCommand $*ACTION;
        :my Bool          $*SUPPRESS-GO-AHEAD;
        <action> | <data>
    }

    token data { <:ascii>+ }

    proto token action {*}
    token action:sym(SE)   { <{IAC}> <command=sym> }
    token action:sym(NOP)  { <{IAC}> <command=sym> }
    token action:sym(DM)   { <{IAC}> <command=sym> }
    token action:sym(BRK)  { <{IAC}> <command=sym> }
    token action:sym(IP)   { <{IAC}> <command=sym> }
    token action:sym(AO)   { <{IAC}> <command=sym> }
    token action:sym(AYT)  { <{IAC}> <command=sym> }
    token action:sym(EC)   { <{IAC}> <command=sym> }
    token action:sym(EL)   { <{IAC}> <command=sym> }
    token action:sym(GA)   {
        | { $*SUPPRESS-GO-AHEAD == False } <{IAC}> <command=sym>
        | { $*SUPPRESS-GO-AHEAD == True  } <.debug: "$/", "Received GA when SUPPRESS-GO-AHEAD was already enabled">
    }
    token action:sym(SB)   {
        <(
            <{IAC}> <command=sym>
            { $*ACTION = SB }
            <subnegotiation>
        )>
        <?action:sym(SE)>
    }
    token action:sym(WILL) {
        <{IAC}> <command=sym>
        { $*ACTION = WILL }
        <negotiation>
    }
    token action:sym(WONT) {
        {IAC}> <command=sym>
        { $*ACTION = WONT }
        <negotiation>
    }
    token action:sym(DO)   {
        <{IAC}> <command=sym>
        { $*ACTION = DO }
        <negotiation>
    }
    token action:sym(DONT) {
        <{IAC}> <command=sym>
        { $*ACTION = DONT }
        <negotiation>
    }

    proto token negotiation {*}
    token negotiation:sym(SGA)($action) {
        <option=sym>
        {
            given $*ACTION {
                when WILL { $*SUPPRESS-GO-AHEAD = True  }
                when WONT { $*SUPPRESS-GO-AHEAD = False }
                when DO   { $*SUPPRESS-GO-AHEAD = True  }
                when DONT { $*SUPPRESS-GO-AHEAD = False }
                when SB   { self.debug: $/, "SUPPRESS-GO-AHEAD does no subnegotiatioddn"> }
            }
        }
    }

    proto token subnegotiation {*}
    token subnegotiation:sym(NAWS) {
        <option=sym>
        <width-upper=<:latin>>
        <width-lower=<:latin>>
        <height-upper=<:latin>>
        <height-lower=<:latin>>
    }
}

role Command {
    has TelnetCommand $.command;
    proto method Str(--> Str) { "{IAC.key} {$!command.key} {{*}}" }
}

class Negotiation does Command {
    has TelnetOption $.option;
    multi method Str(--> Str) { $!option.key }
}

role Subnegotiation does Command {
    has TelnetOption $.option;
    multi method Str(--> Str) { "{$!option.key} {{*}} {SE.key}" }
}

class Subnegotiation::NAMS does Subnegotiation {
    has Int $.width;
    has Int $.height;

    method new(
        Str :$option,
        Str :$width-upper,
        Str :$width-lower,
        Str :$height-upper,
        Str :$height-lower
    ) {
        my $option = TelnetOption($sym);
        my $width  = $width-upper.ord  +< 8 +| $width-lower.ord;
        my $height = $height-upper.ord +< 8 +| $height-lower.ord;
        self.bless: :$option, :$width, :$height;
    }

    multi method Str(--> Str) { "$!width $!height" }
}

class Actions {
    method TOP($/) {
        # ???
    }
}