#Create a simulator object.
set ns [new Simulator]

$ns color 0 Blue
$ns color 1 Red

set duration 10; # duration of simulation

set windowSize 30
set queueSize 10

set link01Capacity [lindex $argv 0]
set link12Capacity [lindex $argv 1]
set link01Delay [lindex $argv 2]
set link12Delay [lindex $argv 3]

#Open the NAM trace file
set file1 [open out.nam w]
$ns namtrace-all $file1

#Open log files
set monfile0 [open Fairness2Mon0.tr w]
set monfile1 [open Fairness2Mon1.tr w]

# select random seed for NS
ns-random 0

#Open the trace file
set file2 [open outWindow.tr w]
set winfile0 [open Fairness2Window0.tr w]
set winfile1 [open Fairness2Window1.tr w]
$ns trace-all $file2

#Define a 'finish' procedure
proc finish {} {
        global ns file1 file2 monfile0 monfile1
        $ns flush-trace
        close $file1
        close $file2
        close $monfile0
        close $monfile1
        exec nam out.nam &
        exit 0
}

#Create 3 nodes
set n0 [$ns node]
set n1 [$ns node]
set n2 [$ns node]

#Connect them in a line 0 -- 1 -- 2
$ns duplex-link $n0 $n1 $link01Capacity $link01Delay DropTail
$ns duplex-link $n1 $n2 $link12Capacity $link12Delay DropTail

$ns queue-limit $n0 $n1 $queueSize
set flink0 [$ns link $n0 $n1]
$ns queue-limit $n1 $n2 $queueSize
set flink1 [$ns link $n1 $n2]

#Set flow monitors
set fmon0 [$ns makeflowmon Fid]
$fmon0 reset
set fmon1 [$ns makeflowmon Fid]
$fmon1 reset

$ns attach-fmon $flink0 $fmon0
$ns attach-fmon $flink1 $fmon1

#Create a TCP agent and attach it to node n0
set tcp0 [new Agent/TCP/Sack1]
$tcp0 set window_ $windowSize
$tcp0 set fid_ 0
$ns attach-agent $n0 $tcp0

#Create a TCP agent and attach it to node n0
set tcp1 [new Agent/TCP/Sack1]
$tcp1 set window_ $windowSize
$tcp1 set fid_ 1
$ns attach-agent $n0 $tcp1

# Create a FTP traffic source and attach it to tcp0
set ftp0 [new Application/FTP]
$ftp0 set packetSize_ 500
$ftp0 set interval_ 0.001
$ftp0 attach-agent $tcp0

# Create a FTP traffic source and attach it to tcp1
set ftp1 [new Application/FTP]
$ftp1 set packetSize_ 500
$ftp1 set interval_ 0.001
$ftp1 attach-agent $tcp1

#Create a TCP Sink  agent (a traffic sink) and attach it to node n1
set tcpSink0 [new Agent/TCPSink/Sack1]
$ns attach-agent $n1 $tcpSink0

#Create a TCP Sink  agent (a traffic sink) and attach it to node n2
set tcpSink1 [new Agent/TCPSink/Sack1]
$ns attach-agent $n2 $tcpSink1

#Connect the traffic sources with the traffic sinks
$ns connect $tcp0 $tcpSink0
$ns connect $tcp1 $tcpSink1

#Schedule events for the FTP agent
$ns at 1.5 "$ftp0 start"
$ns at 0.5 "$ftp1 start"

proc plotWindow {tcpSource file} {
global ns windowSize
set time 0.02
set now [$ns now]
set cwnd [$tcpSource set cwnd_]
if { $cwnd < $windowSize } then {
puts $file "$now $cwnd"
} else {
puts $file "$now $windowSize"
}
$ns at [expr $now+$time] "plotWindow $tcpSource $file"
}


proc plotTPut {flowmon lastpktsd n file} {
    global ns laspktsd
    set time 0.2
    set now [$ns now]
    # get flow classifier
    set fcl [$flowmon classifier]
    # get flow number 1
    set flow [$fcl lookup auto 0 0 $n]

    if { $flow !="" } then {
    set drops [$flow set pdrops_]
    set pktsa [$flow set parrivals_]
    set pktsd [$flow set pdepartures_]
    set queue [$flow set pkts_]
    set tput [expr 1.0*($pktsd -$lastpktsd)/$time]
    set lastpktsd $pktsd
    if { $pktsa > 0 } then {
        set droprate [expr 1.0*$drops / $pktsa]
    } else {
        set droprate 0
    }
    puts $file "$now $drops $pktsa $pktsd $droprate $tput $queue"
    }
    $ns at [expr $now+$time] "plotTPut $flowmon $lastpktsd $n $file"
}
set lpktsd(0) 0
set lpktsd(1) 0

$ns at 0.1 "plotWindow $tcp0 $winfile0"
$ns at 0.1 "plotWindow $tcp1 $winfile1"
$ns at 0.1 "plotTPut $fmon0 $lpktsd(0) 0 $monfile0"
$ns at 0.1 "plotTPut $fmon1 $lpktsd(1) 1 $monfile1"

#Call the finish procedure after $duration seconds of simulation time
$ns at $duration "finish"

#Run the simulation
$ns run